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Chang YC, Venkateswar Reddy M, Suzuki H, Terayama T, Mawatari Y, Seki C, Sarkar O. Characterization of Ralstonia insidiosa C1 isolated from Alpine regions: Capability in polyhydroxyalkanoates degradation and production. J Hazard Mater 2024; 471:134348. [PMID: 38653138 DOI: 10.1016/j.jhazmat.2024.134348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/05/2024] [Accepted: 04/17/2024] [Indexed: 04/25/2024]
Abstract
This study ventures into the exploration of potential poly-3-hydroxybutyrate (PHB) degradation in alpine environments. PHB-degrading bacteria were identified in both campus soil, representing a residential area, and Mt. Kurodake soil, an alpine region in Hokkaido, Japan. Next-generation sequencing analysis indicated that the campus soil exhibited higher microbial diversity, while Ralstonia insidiosa C1, isolated from Mt. Kurodake soil, displayed the highest proficiency in PHB degradation. R. insidiosa C1 efficiently degraded up to 3% (w/v) of PHB and various films composed of other biopolymers at 14 °C. This bacterium synthesized homopolymers using substrates such as 3-hydroxybutyric acid, sugars, and acetic acid, while also produced copolymers using a mixture of fatty acids. The analysis results confirmed that the biopolymer synthesized by strain C1 using glucose was PHB, with physical properties comparable to commercial products. The unique capabilities of R. insidiosa C1, encompassing both the production and degradation of bioplastics, highlight its potential to establish a novel material circulation model.
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Affiliation(s)
- Young-Cheol Chang
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, Muroran Institute of Technology, Hokkaido 050-8585, Japan; Department of Sciences and Informatics, Course of Chemical and Biological Systems, Muroran Institute of Technology, 27-1 Mizumoto, Muroran 050-8585, Japan.
| | - M Venkateswar Reddy
- Department of Civil and Environmental Engineering, Colorado State University, Fort Collins, Colorado 80523, USA
| | - Hinako Suzuki
- Department of Sciences and Informatics, Course of Chemical and Biological Systems, Muroran Institute of Technology, 27-1 Mizumoto, Muroran 050-8585, Japan
| | - Takumi Terayama
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, Muroran Institute of Technology, Hokkaido 050-8585, Japan
| | - Yasuteru Mawatari
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, Muroran Institute of Technology, Hokkaido 050-8585, Japan; Department of Sciences and Informatics, Course of Chemical and Biological Systems, Muroran Institute of Technology, 27-1 Mizumoto, Muroran 050-8585, Japan
| | - Chigusa Seki
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, Muroran Institute of Technology, Hokkaido 050-8585, Japan; Department of Sciences and Informatics, Course of Chemical and Biological Systems, Muroran Institute of Technology, 27-1 Mizumoto, Muroran 050-8585, Japan
| | - Omprakash Sarkar
- Biochemical Process Engineering, Division of Chemical Engineering, Department of Civil, Environmental, and Natural Resources Engineering, Luleå University of Technology, 971 87 Luleå, Sweden
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Chang YC, Reddy MV, Tsukiori Y, Mawatari Y, Choi D. Production of polyhydroxyalkanoates using sewage and cheese whey. Heliyon 2023; 9:e23130. [PMID: 38144304 PMCID: PMC10746463 DOI: 10.1016/j.heliyon.2023.e23130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 11/14/2023] [Accepted: 11/27/2023] [Indexed: 12/26/2023] Open
Abstract
Recently, polyhydroxyalkanoates (PHAs) have been produced using raw sewage in our laboratory; however, the production concentrations are low. Therefore, this study aimed to enhance PHA production by applying different strategies. PHA production was higher in sewage-containing medium than in mineral salt medium and was enhanced 22-fold after glucose supplementation. A relatively high degree of glucose consumption (83.6 ± 1.59 %) was also achieved. Bacteria incubated with cheese whey diluted with sewage showed higher PHA production than bacteria incubated with cheese whey diluted with distilled water did. The expression of the PHA synthase gene (phaC) was evaluated via real-time polymerase chain reaction using low- and high-carbon-containing sewage. Relatively higher phaC expression levels were observed in high-carbon-containing sewage but at lower nitrogen concentrations. The characteristics of the produced PHA were comparable to those of standard PHA. Therefore, this study revealed that the bacterium Bacillus sp. CYR1 can produce PHA from low- or high-carbon-containing wastewater.
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Affiliation(s)
- Young-Cheol Chang
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, Muroran Institute of Technology, Hokkaido, 050-8585, Japan
| | - M. Venkateswar Reddy
- Department of Civil and Environmental Engineering, Colorado State University, Fort Collins, CO, 80523, USA
| | - Yusei Tsukiori
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, Muroran Institute of Technology, Hokkaido, 050-8585, Japan
| | - Yasuteru Mawatari
- Research Center for Environmentally Friendly Materials Engineering, Muroran Institute of Technology, Hokkaido, 050-8585, Japan
| | - DuBok Choi
- Faculty of Advanced Industry Convergence, Chosun University, Gwangju, 61452, South Korea
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Gol AK, Bodanki CS, Yadoji H, Reddy G, Reddy MV. Decompression of Paralabral Cyst near Axillary Nerve: A Case Report. J Orthop Case Rep 2023; 13:52-56. [PMID: 37753119 PMCID: PMC10519306 DOI: 10.13107/jocr.2023.v13.i09.3874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/12/2023] [Indexed: 09/28/2023] Open
Abstract
Introduction Paralabral cyst is benign fluid-filled lesion that occurs adjacent to glenoid labrum. Origin of the cyst can be traumatic or atraumatic. This cystic lesion can compress nearby axillary nerve or suprascapular nerve, resulting in shoulder pain and numbness. In this case report, we will discuss about anteroinferior paralabral cyst with axillary neuropathy in atraumatic condition. Case Report A 35-year-old male was admitted in our institute with complaining of numbness in the mid-part of the lateral arm and pain in the posterior aspect in the left shoulder for 2 weeks. The patient has on-and-off pain in the left shoulder on lifting weight. He had no history of trauma. X-ray was normal. On examination, tenderness presents over the dorsal aspect of shoulder and reduced sensations over deltoid muscle (regimen badge sign). Deltoid atrophy was noted. Range of motion was normal. On examination, cervical spine was normal, and reduced sensation over the lateral aspect of arm and deltoid atrophy was present. Magnetic resonance imaging (MRI) shows large multiloculated paralabral cyst caudal to inferior glenoid rim. The diagnosis was compressive axillary neuropathy which was confirmed by nerve condition study. Conclusion According to this case report, accurate early clinical examination and MRI evaluation are crucial in patients with atraumatic shoulder pain associated with neurological symptoms. On identification, cyst can be successfully decompressed by shoulder arthroscopy which can prevent axillary nerve damage, muscle denervation, and also recurrence of cyst can be avoided.
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Affiliation(s)
- Abhishek K Gol
- Department of Arthroscopy and Shoulder Surgery, Trinity Hospital, Rajkot, Gujarat, India
| | - Chandrasekhar S Bodanki
- Department of Arthroscopy and Shoulder Surgery, Sunshine Hospital and Research Centre, Secundarabad, Telangana, India
| | - Harikrishna Yadoji
- Department of Arthroscopy and Shoulder Surgery, Sunshine Hospital and Research Centre, Secundarabad, Telangana, India
| | - Guruva Reddy
- Department of Orthopedics, Sunshine Hospital and Research Centre, Secundarabad, Telangana, India
| | - M V Reddy
- Department of Orthopedics, Sunshine Hospital and Research Centre, Secundarabad, Telangana, India
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Saito K, Reddy MV, Sarkar O, Kumar AN, Choi D, Chang YC. Quantification of the Monomer Compositions of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and Poly(3-hydroxyvalerate) by Alkaline Hydrolysis and Using High-Performance Liquid Chromatography. Bioengineering (Basel) 2023; 10:bioengineering10050618. [PMID: 37237688 DOI: 10.3390/bioengineering10050618] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Revised: 05/12/2023] [Accepted: 05/18/2023] [Indexed: 05/28/2023] Open
Abstract
With the growing interest in bioplastics, there is an urgent need to develop rapid analysis methods linked to production technology development. This study focused on the production of a commercially non-available homopolymer, poly(3-hydroxyvalerate) (P(3HV)), and a commercially available copolymer, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (P(3HB-co-3HV)), through fermentation using two different bacterial strains. The bacteria Chromobacterium violaceum and Bacillus sp. CYR1 were used to produce P(3HV) and P(3HB-co-3HV), respectively. The bacterium Bacillus sp. CYR1 produced 415 mg/L of P(3HB-co-3HV) when incubated with acetic acid and valeric acid as the carbon sources, whereas the bacterium C. violaceum produced 0.198 g of P(3HV)/g dry biomass when incubated with sodium valerate as the carbon source. Additionally, we developed a fast, simple, and inexpensive method to quantify P(3HV) and P(3HB-co-3HV) using high-performance liquid chromatography (HPLC). As the alkaline decomposition of P(3HB-co-3HV) releases 2-butenoic acid (2BE) and 2-pentenoic acid (2PE), we were able to determine the concentration using HPLC. Moreover, calibration curves were prepared using standard 2BE and 2PE, along with sample 2BE and 2PE produced by the alkaline decomposition of poly(3-hydroxybutyrate) and P(3HV), respectively. Finally, the HPLC results obtained by our new method were compared using gas chromatography (GC) analysis.
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Affiliation(s)
- Kyo Saito
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, Muroran Institute of Technology, 27-1 Mizumoto, Muroran 050-8585, Japan
| | - M Venkateswar Reddy
- Department of Civil and Environmental Engineering, Colorado State University, Fort Collins, CO 80523, USA
| | - Omprakash Sarkar
- Department of Civil, Environmental and Natural Resources Engineering, Luleå University of Technology, 97187 Luleå, Sweden
| | - A Naresh Kumar
- Department of Environmental Science and Technology, University of Maryland, College Park, MD 20742, USA
| | - DuBok Choi
- Faculty of Advanced Industry Convergence, Chosun University, Kwangju 61452, Republic of Korea
| | - Young-Cheol Chang
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, Muroran Institute of Technology, 27-1 Mizumoto, Muroran 050-8585, Japan
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Yadoji HK, Bodanki C, Reddy MV, Reddy AVG. Arthroscopic Anterior Capsule Reconstruction Using Fascia Lata Autograft and Knotless Fibretak: A Case Report. J Orthop Case Rep 2022; 12:91-95. [PMID: 36660153 PMCID: PMC9826548 DOI: 10.13107/jocr.2022.v12.i05.2832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 01/19/2022] [Indexed: 01/22/2023] Open
Abstract
Introduction Shoulder has multidirectional mobility with capsule and rotator cuff as stabilizers. Irreparable subscapularis tears are relatively uncommon. Anterior capsule reconstruction (ACR) is one of the different modalities of treatment for irreparable subscapularis tears. Anterior capsular reconstruction can be performed using hamstring autograft, tibialis anterior allograft, and human dermal allograft. Procedures using hamstring autograft and tibialis anterior allograft reported severe capsular deficiency, recurrent dislocation, and subluxations. Dermal allograft is routinely used for ACR anterior capsule reconstruction. But However, there are no reports of Fascia lata autograft being used for ACR anterior capsule reconstruction. As fascia lata is an autograft, it may have a better chance of healing than dermal allograft. Case Report A 60-year year-old male patient came with history of slip and fall at home 3 months ago and injured his left shoulder. Magnetic resonance imaging MRI is showing subscapularis tear retracted medial to glenoid and anterior supraspinatus tear with minimal retraction. The aim of this case report is to describe in detail the arthroscopic technique of ACR anterior capsule reconstruction using fascia lata autograft using the new knotless all suture anchors (fibereTak) on glenoid. Conclusion Fascia lata being an autograft may have better healing potential, but its superiority over dermal allografts in the setting of ACR anterior capsule reconstruction needs further studies.
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Affiliation(s)
- Hari Krishna Yadoji
- Department of Arthroscopy and Shoulder Surgery, Sunshine Hospital, Secunderabad, Telangana, India,Address of Correspondence: Dr. Hari Krishna Yadoji, Department of Arthroscopy and Shoulder Surgery, Sunshine Hospital, Secunderabad - 500 003, Telangana, India. E-mail:
| | - Chandrasekhar Bodanki
- Department of Arthroscopy and Shoulder Surgery, Sunshine Hospital, Secunderabad, Telangana, India
| | - M V Reddy
- Department of Orthopaedic, Sunshine Hospital, Secunderabad, Telangana, India
| | - A V Gurava Reddy
- Department of Orthopaedic, Sunshine Hospital, Secunderabad, Telangana, India
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Reddy MV, Steinbüchel A. 3,3'-Thiodipropionic acid (TDP), a possible precursor for the synthesis of polythioesters: identification of TDP transport proteins in Variovorax paradoxus TBEA6. Appl Microbiol Biotechnol 2021; 105:3733-3743. [PMID: 33900422 PMCID: PMC8102459 DOI: 10.1007/s00253-021-11294-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 03/21/2021] [Accepted: 04/12/2021] [Indexed: 11/26/2022]
Abstract
3,3'-Thiodipropionic acid (TDP) is an antioxidant, which can be used as precursor carbon source to synthesize polythioesters. The bacterium Variovorax paradoxus TBEA6 strain can use TDP as a single source of carbon and energy. In the present study, experiments were carried out to identify proteins involved in the transport of TDP into the cells of strain TBEA6. Hence, eight putative tctC genes, which encode for the TctC proteins, were amplified from genomic DNA of TBEA6 strain using polymerase chain reaction and expressed in E. coli BL21 cells. Cells were grown in auto-induction medium, and protein purification was done using His Spin Trap affinity columns. Purity and molecular weight of each protein were confirmed by SDS-PAGE analysis. Protein-ligand interactions were monitored in thermoshift assays using the real-time PCR system. Two TctC proteins (locus tags VPARA-44430 and VPARA-01760) out of eight proteins showed a significant shift in their melting temperatures when they interact with the ligand (TDP or gluconate). The responsible genes were deleted in the genome of TBEA6 using suicide plasmid pJQ200mp18Tc, and single deletion mutants of the two candidate genes were subsequently generated. Finally, growth of the wild-type strain (TBEA6) and the two mutant strains (ΔVPARA-44430 and ΔVPARA-01760) were monitored and compared using TDP or gluconate as carbon sources. Wild type strains were successfully grown with TDP or gluconate. From the two mutant strains, one (ΔVPARA-44430) was unable to grow with TDP indicating that the tctC gene with locus tag VPARA-44430 is involved in the uptake of TDP.Key Points• Putative tctC genes from V. paradoxus TBEA6 were heterologously expressed in E. coli.• Protein-ligand interactions monitored in thermoshift assays using the real-time PCR.• tctC gene with locus tag VPARA-44430 is involved in the uptake of TDP.
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Affiliation(s)
- M Venkateswar Reddy
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, 48149, Münster, Germany
| | - Alexander Steinbüchel
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms-Universität Münster, 48149, Münster, Germany.
- Environmental Sciences Department, King Abdulaziz University, Jeddah, Saudi Arabia.
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Venkateswar Reddy M, Kumar G, Mohanakrishna G, Shobana S, Al-Raoush RI. Review on the production of medium and small chain fatty acids through waste valorization and CO 2 fixation. Bioresour Technol 2020; 309:123400. [PMID: 32371319 DOI: 10.1016/j.biortech.2020.123400] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 04/15/2020] [Accepted: 04/16/2020] [Indexed: 06/11/2023]
Abstract
The developing approaches in the recovery of resources from biowastes for the production of renewable value-added products and fuels, using microbial cultures as bio-catalyst have now became promising aspect. In the path of anaerobic digestion, the microorganisms are assisting transformation of a complex organic feedstock/waste to biomass and biogas. This potentiality consequently leads to the production of intermediate precursors of renewable value-added products. Particularly, a set of anaerobic pathways in the fermentation process, yields small-chain fatty acids (SCFA), and medium-chain fatty acids (MCFA) via chain elongation pathways from waste valorization and CO2 fixation. This review focuses on the production of SCFA and MCFA from CO2, synthetic substrates and waste materials. Moreover, the review introduces the metabolic engineering of Escherichia coli and Saccharomyces cerevisiae for SCFAs/MCFAs production. Furtherly, it concludes that future critical research might target progress of this promising approach as a valorization of complex organic wastes.
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Affiliation(s)
- M Venkateswar Reddy
- Institut für Molekulare Mikrobiologie und Biotechnologie, Westfälische Wilhelms Universität, Corrensstr. 3, 48149 Münster, Germany
| | - Gopalakrishnan Kumar
- School of Civil and Environmental Engineering, Yonsei University, Seoul 03722, Republic of Korea
| | - Gunda Mohanakrishna
- Department of Civil and Architectural Engineering, College of Engineering, Qatar University, P O Box 2713, Doha, Qatar.
| | - Sutha Shobana
- Department of Chemistry & Research Centre, Mohamed Sathak Engineering College, Kilakarai, 623 806 Ramanathapuram, Tamil Nadu, India
| | - Riyadh I Al-Raoush
- Department of Civil and Architectural Engineering, College of Engineering, Qatar University, P O Box 2713, Doha, Qatar
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Reddy MV, Mawatari Y, Onodera R, Nakamura Y, Yajima Y, Chang YC. Bacterial conversion of waste into polyhydroxybutyrate (PHB): A new approach of bio-circular economy for treating waste and energy generation. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.biteb.2019.100246] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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Ali GAM, Divyashree A, Supriya S, Chong KF, Ethiraj AS, Reddy MV, Algarni H, Hegde G. Carbon nanospheres derived from Lablab purpureus for high performance supercapacitor electrodes: a green approach. Dalton Trans 2018; 46:14034-14044. [PMID: 28979958 DOI: 10.1039/c7dt02392h] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Carbon nanospheres derived from a natural source using a green approach were reported. Lablab purpureus seeds were pyrolyzed at different temperatures to produce carbon nanospheres for supercapacitor electrode materials. The synthesized carbon nanospheres were analyzed using SEM, TEM, FTIR, TGA, Raman spectroscopy, BET and XRD. They were later fabricated into electrodes for cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy testing. The specific capacitances were found to be 300, 265 and 175 F g-1 in 5 M KOH electrolyte for carbon nanospheres synthesized at 800, 700 and 500 °C, respectively. These are on a par with those of prior electrodes made of biologically derived carbon nanospheres but the cycle lives were remarkably higher than those of any previous efforts. The electrodes showed 94% capacitance retention even after 5200 charge/discharge cycles entailing excellent recycling durability. In addition, the practical symmetrical supercapacitor showed good electrochemical behaviour under a potential window up to 1.7 V. This brings us one step closer to fabricating a commercial green electrode which exhibits high performance for supercapacitors. This is also a waste to wealth approach based carbon material for cost effective supercapacitors with high performance for power storage devices.
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Affiliation(s)
- Gomaa A M Ali
- Faculty of Industrial Sciences & Technology, Universiti Malaysia Pahang, Gambang, 26300, Kuantan, Malaysia
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Reddy MV, Eachempati K, Gurava Reddy AV, Mugalur A. Error Analysis: How Precise is Fused Deposition Modeling in Fabrication of Bone Models in Comparison to the Parent Bones? Indian J Orthop 2018; 52:196-201. [PMID: 29576649 PMCID: PMC5858215 DOI: 10.4103/ortho.ijortho_312_16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND Rapid prototyping (RP) is used widely in dental and faciomaxillary surgery with anecdotal uses in orthopedics. The purview of RP in orthopedics is vast. However, there is no error analysis reported in the literature on bone models generated using office-based RP. This study evaluates the accuracy of fused deposition modeling (FDM) using standard tessellation language (STL) files and errors generated during the fabrication of bone models. MATERIALS AND METHODS Nine dry bones were selected and were computed tomography (CT) scanned. STL files were procured from the CT scans and three-dimensional (3D) models of the bones were printed using our in-house FDM based 3D printer using Acrylonitrile Butadiene Styrene (ABS) filament. Measurements were made on the bone and 3D models according to data collection procedures for forensic skeletal material. Statistical analysis was performed to establish interobserver co-relation for measurements on dry bones and the 3D bone models. Statistical analysis was performed using SPSS version 13.0 software to analyze the collected data. RESULTS The inter-observer reliability was established using intra-class coefficient for both the dry bones and the 3D models. The mean of absolute difference is 0.4 that is very minimal. The 3D models are comparable to the dry bones. CONCLUSIONS STL file dependent FDM using ABS material produces near-anatomical 3D models. The high 3D accuracy hold a promise in the clinical scenario for preoperative planning, mock surgery, and choice of implants and prostheses, especially in complicated acetabular trauma and complex hip surgeries.
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Affiliation(s)
- M V Reddy
- Department of Orthopaedics, Sunshine Hospitals, Secunderabad, India
| | | | - A V Gurava Reddy
- Department of Orthopaedics, Sunshine Hospitals, Secunderabad, India
| | - Aakash Mugalur
- Department of Orthopaedics, Sri Narayani Hospital and Research Centre, Vellore, Tamil Nadu, India,Address for correspondence: Dr. Aakash Mugalur, Department of Orthopaedics, Sri Narayani Hospital and Research Centre, Vellore, Tamil Nadu, India. E-mail:
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Zhou J, Reddy MV, Wilson BKJ, Blair DA, Taha A, Frampton CM, Eiholzer RA, Gan PYC, Ziad F, Thotathil Z, Kirs S, Hung NA, Royds JA, Slatter TL. MR Imaging Characteristics Associate with Tumor-Associated Macrophages in Glioblastoma and Provide an Improved Signature for Survival Prognostication. AJNR Am J Neuroradiol 2017; 39:252-259. [PMID: 29191871 DOI: 10.3174/ajnr.a5441] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 09/07/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND PURPOSE In glioblastoma, tumor-associated macrophages have tumor-promoting properties. This study determined whether routine MR imaging features could predict molecular subtypes of glioblastoma that differ in the content of tumor-associated macrophages. MATERIALS AND METHODS Seven internally derived MR imaging features were assessed in 180 patients, and 25 features from the Visually AcceSAble Rembrandt Images feature set were assessed in 164 patients. Glioblastomas were divided into subtypes based on the telomere maintenance mechanism: alternative lengthening of telomeres positive (ALT+) and negative (ALT-) and the content of tumor-associated macrophages (with [M+] or without [M-] a high content of macrophages). The 3 most frequent subtypes (ALT+/M-, ALT-/M+, and ALT-/M-) were correlated with MR imaging features and clinical parameters. The fourth group (ALT+/M+) did not have enough cases for correlation with MR imaging features. RESULTS Tumors with a regular margin and those lacking a fungating margin, an expansive T1/FLAIR ratio, and reduced ependymal extension were more frequent in the subgroup of ALT+/M- (P < .05). Radiologic necrosis, lack of cystic component (by both criteria), and extensive peritumoral edema were more frequent in ALT-/M+ tumors (P < .05). Multivariate testing with a Cox regression analysis found the cystic imaging feature was additive to tumor subtype, and O6-methylguanine methyltransferase (MGMT) status to predict improved patient survival (P < .05). CONCLUSIONS Glioblastomas with tumor-associated macrophages are associated with routine MR imaging features consistent with these tumors being more aggressive. Inclusion of cystic change with molecular subtypes and MGMT status provided a better estimate of survival.
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Affiliation(s)
- J Zhou
- From the Departments of Radiology (J.Z., M.V.R., B.K.J.W.) .,Department of Pathology (J.Z., R.A.E., N.A.H., J.A.R., T.L.S.)
| | - M V Reddy
- From the Departments of Radiology (J.Z., M.V.R., B.K.J.W.)
| | - B K J Wilson
- From the Departments of Radiology (J.Z., M.V.R., B.K.J.W.)
| | | | - A Taha
- Neurosurgery (A.T.), Southern District Health Board, Dunedin, New Zealand.,Surgical Sciences (A.T., S.K.), Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - C M Frampton
- Department of Medicine (C.M.F.), University of Otago, Christchurch, New Zealand
| | - R A Eiholzer
- Department of Pathology (J.Z., R.A.E., N.A.H., J.A.R., T.L.S.)
| | | | | | - Z Thotathil
- Medical Oncology (Z.T.), Waikato District Health Board, Hamilton, New Zealand
| | - S Kirs
- Surgical Sciences (A.T., S.K.), Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | - N A Hung
- Department of Pathology (J.Z., R.A.E., N.A.H., J.A.R., T.L.S.)
| | - J A Royds
- Department of Pathology (J.Z., R.A.E., N.A.H., J.A.R., T.L.S.)
| | - T L Slatter
- Department of Pathology (J.Z., R.A.E., N.A.H., J.A.R., T.L.S.)
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Azarniya A, Sovizi S, Azarniya A, Rahmani Taji Boyuk MR, Varol T, Nithyadharseni P, Madaah Hosseini HR, Ramakrishna S, Reddy MV. Physicomechanical properties of spark plasma sintered carbon nanotube-containing ceramic matrix nanocomposites. Nanoscale 2017; 9:12779-12820. [PMID: 28832057 DOI: 10.1039/c7nr01878a] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Recently, a wide variety of research works have focused on carbon nanotube (CNT)-ceramic matrix nanocomposites. In many cases, these novel materials are produced through conventional powder metallurgy methods including hot pressing, conventional sintering, and hot isostatic pressing. However, spark plasma sintering (SPS) as a novel and efficient consolidation technique is exploited for the full densification of high-temperature ceramic systems. In these binary nanocomposites, CNTs are added to ceramic matrices to noticeably modify their inferior properties and SPS is employed to produce fully dense compacts. In this review, a broad overview of these systems is provided and the potential influences of CNTs on their functional and structural properties are addressed. The technical challenges are then mentioned and the ongoing debates over overcoming these drawbacks are fully highlighted. The structural classification used is material-oriented. It helps the readers to easily find the material systems of interest. The SPSed CNT-containing ceramic matrix nanocomposites are generally categorized into four main classes: CNT-oxide systems; CNT-nitride systems, CNT-carbide systems, and CNT-boride systems. A large number of original curves and bubble maps are provided to fully summarize the experimental results reported in the literature. They pave the way for obviously selecting the ceramic systems required for each industrial application. The properties in consideration include the relative density, hardness, yield strength, fracture toughness, electrical and thermal conductivities, modulus, and flexural strength. These unique graphs facilitate the comparison between reported results and help the reader to easily distinguish the best method for producing the ceramic systems of interest and the optimal conditions under which the superior properties can be reached. The authors have concentrated on the microstructure evolution-physicomechanical property relationship and tried to relate each property to pertinent microstructural phenomena and address why the properties are degraded or enhanced with the variation of SPS conditions or material parameters.
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Affiliation(s)
- Abolfazl Azarniya
- Department of Materials Science and Engineering, Sharif University of Technology, P.O. Box 11155-9466, Azadi Avenue, Tehran, Iran.
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Venkateswar Reddy M, Mawatari Y, Onodera R, Nakamura Y, Yajima Y, Chang YC. Polyhydroxyalkanoates (PHA) production from synthetic waste using Pseudomonas pseudoflava: PHA synthase enzyme activity analysis from P. pseudoflava and P. palleronii. Bioresour Technol 2017; 234:99-105. [PMID: 28319778 DOI: 10.1016/j.biortech.2017.03.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 02/28/2017] [Accepted: 03/01/2017] [Indexed: 06/06/2023]
Abstract
Synthetic wastewater (SW) at various carbon concentrations (5-60g/l) were evaluated for polyhydroxyalkanoates (PHA) production using the bacteria Pseudomonas pseudoflava. Bacteria showed highest PHA production with 20g/l (57±5%), and highest carbon removal at 5g/l (74±6%) concentrations respectively. Structure, molecular weight, and thermal properties of the produced PHA were evaluated using various analytical techniques. Bacteria produced homo-polymer [poly-3-hydroxybutyrate (P3HB)] when only acetate was used as carbon source; and it produced co-polymer [poly-(3-hydroxybutyrate-co-3-hydroxyvalerate) P(3HB-co-3HV)] by addition of co-substrate propionate. PHA synthase, the enzyme which produce PHA was extracted from two bacterial strains i.e., P. pseudoflava and P. palleronii and its molecular weight was analysed using SDS-PAGE. Protein concentration, and PHA synthase enzyme activity of P. pseudoflava and P. palleronii was carried out using spectrophotometer. Results denoted that P. pseudoflava can be used for degradation of organic carbon persistent in wastewaters and their subsequent conversion into PHA.
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Affiliation(s)
- M Venkateswar Reddy
- Department of Applied Sciences, College of Environmental Technology, Muroran Institute of Technology, 27-1 Mizumoto, Muroran, Hokkaido 050-8585, Japan
| | - Yasuteru Mawatari
- Research Center for Environmentally Friendly Materials Engineering, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran, Hokkaido 050-8585, Japan
| | - Rui Onodera
- Department of Applied Sciences, College of Environmental Technology, Muroran Institute of Technology, 27-1 Mizumoto, Muroran, Hokkaido 050-8585, Japan
| | - Yuki Nakamura
- Department of Applied Sciences, College of Environmental Technology, Muroran Institute of Technology, 27-1 Mizumoto, Muroran, Hokkaido 050-8585, Japan
| | - Yuka Yajima
- Department of Applied Sciences, College of Environmental Technology, Muroran Institute of Technology, 27-1 Mizumoto, Muroran, Hokkaido 050-8585, Japan
| | - Young-Cheol Chang
- Department of Applied Sciences, College of Environmental Technology, Muroran Institute of Technology, 27-1 Mizumoto, Muroran, Hokkaido 050-8585, Japan.
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Venkateswar Reddy M, Mawatari Y, Yajima Y, Satoh K, Venkata Mohan S, Chang YC. Production of poly-3-hydroxybutyrate (P3HB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) P(3HB-co-3HV) from synthetic wastewater using Hydrogenophaga palleronii. Bioresour Technol 2016; 215:155-162. [PMID: 26995321 DOI: 10.1016/j.biortech.2016.03.025] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 03/01/2016] [Accepted: 03/02/2016] [Indexed: 06/05/2023]
Abstract
In the present study, synthetic wastewater (SW) was used for production of poly-3-hydroxybutyrate (P3HB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) P(3HB-co-3HV) using the bacteria Hydrogenophaga palleronii. SW at various volatile fatty acids concentrations (5-60g/l) was evaluated for the growth and biopolymer production using H. palleronii. Substrate degradation was analyzed using total organic carbon (TOC) analyzer and high pressure liquid chromatography (HPLC). H. palleronii showed highest and lowest removal of TOC at 5g/l (88±4%) and 60g/l (15±6%) respectively. Among all the concentrations evaluated, bacteria showed highest biopolymer production with 20g/l (63±5%), followed by 30g/l (58±3%) and 40g/l (56±2%). Lowest biopolymer production was observed at 5g/l concentration (21±3%). Structure, molecular weight, and thermal properties of the produced biopolymer were analyzed. These results denoted that the strain H. palleronii can be used for degradation of high concentration of volatile fatty acids persistent in wastewaters and their subsequent conversion into useable biopolymers.
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Affiliation(s)
- M Venkateswar Reddy
- Department of Applied Sciences, College of Environmental Technology, Muroran Institute of Technology, 27-1 Mizumoto, Muroran, Hokkaido 050-8585, Japan
| | - Yasuteru Mawatari
- Research Center for Environmentally Friendly Materials Engineering, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran, Hokkaido 050-8585, Japan
| | - Yuka Yajima
- Department of Applied Sciences, College of Environmental Technology, Muroran Institute of Technology, 27-1 Mizumoto, Muroran, Hokkaido 050-8585, Japan
| | - Kohki Satoh
- Department of Information and Electronic Engineering, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran, Hokkaido 050-8585, Japan
| | - S Venkata Mohan
- Bioengineering and Environmental Sciences (BEES), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500007, India
| | - Young-Cheol Chang
- Department of Applied Sciences, College of Environmental Technology, Muroran Institute of Technology, 27-1 Mizumoto, Muroran, Hokkaido 050-8585, Japan.
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Petnikota S, Teo KW, Chen L, Sim A, Marka SK, Reddy MV, Srikanth VVSS, Adams S, Chowdari BVR. Exfoliated Graphene Oxide/MoO2 Composites as Anode Materials in Lithium-Ion Batteries: An Insight into Intercalation of Li and Conversion Mechanism of MoO2. ACS Appl Mater Interfaces 2016; 8:10884-96. [PMID: 27057928 DOI: 10.1021/acsami.6b02049] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Exfoliated graphene oxide (EG)/MoO2 composites are synthesized by a simple solid-state graphenothermal reduction method. Graphene oxide (GO) is used as a reducing agent to reduce MoO3 and as a source for EG. The formation of different submicron sized morphologies such as spheres, rods, flowers, etc., of monoclinic MoO2 on EG surfaces is confirmed by complementary characterization techniques. As-synthesized EG/MoO2 composite with a higher weight percentage of EG performed excellently as an anode material in lithium-ion batteries. The galvanostatic cycling studies aided with postcycling cyclic voltammetry and galvanostatic intermittent titrations followed by ex situ structural studies clearly indicate that Li intercalation into MoO2 is transformed into conversion upon aging at low current densities while intercalation mechanism is preferably taking place at higher current rates. The intercalation mechanism is found to be promising for steady-state capacity throughout the cycling because of excess graphene and higher current density even in the operating voltage window of 0.005-3.0 V in which MoO2 undergoes conversion below 0.8 V.
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Affiliation(s)
- Shaikshavali Petnikota
- School of Engineering Sciences and Technology, University of Hyderabad , Gachibowli, Hyderabad 500046, India
| | - Keefe Wayne Teo
- NUS High School of Mathematics and Science , 20 Clementi Avenue 1, Singapore 129957, Singapore
| | - Luo Chen
- NUS High School of Mathematics and Science , 20 Clementi Avenue 1, Singapore 129957, Singapore
| | - Amos Sim
- NUS High School of Mathematics and Science , 20 Clementi Avenue 1, Singapore 129957, Singapore
| | - Sandeep Kumar Marka
- School of Engineering Sciences and Technology, University of Hyderabad , Gachibowli, Hyderabad 500046, India
| | | | - V V S S Srikanth
- School of Engineering Sciences and Technology, University of Hyderabad , Gachibowli, Hyderabad 500046, India
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Chang YC, Reddy MV, Umemoto H, Sato Y, Kang MH, Yajima Y, Kikuchi S. Bio-Augmentation of Cupriavidus sp. CY-1 into 2,4-D Contaminated Soil: Microbial Community Analysis by Culture Dependent and Independent Techniques. PLoS One 2015; 10:e0145057. [PMID: 26710231 PMCID: PMC4699198 DOI: 10.1371/journal.pone.0145057] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2015] [Accepted: 11/29/2015] [Indexed: 11/21/2022] Open
Abstract
In the present study, a 2,4-dichlorophenoxyacetic acid (2,4-D) degrading bacterial strain CY-1 was isolated from the forest soil. Based on physiological, biochemical and 16S rRNA gene sequence analysis it was identified as Cupriavidus sp. CY-1. Further 2,4-D degradation experiments at different concentrations (200 to 800 mg l-1) were carried out using CY-1. Effect of NaCl and KNO3 on 2,4-D degradation was also evaluated. Degradation of 2,4-D and the metabolites produced during degradation process were analyzed using high pressure liquid chromatography (HPLC) and GC-MS respectively. The amount of chloride ions produced during the 2,4-D degradation were analyzed by Ion chromatography (IC) and it is stoichiometric with 2,4-D dechlorination. Furthermore two different types of soils collected from two different sources were used for 2,4-D degradation studies. The isolated strain CY-1 was bio-augmented into 2,4-D contaminated soils to analyze its degradation ability. Culture independent methods like denaturing gradient gel electrophoresis (DGGE) and terminal restriction fragment length polymorphism (T-RFLP), and culture dependent methods like colony forming units (CFU) and most probable number (MPN) were used to analyze the survivability of strain CY-1 in contaminated soil. Results of T-RFLP were coincident with the DGGE analysis. From the DGGE, T-RFLP, MPN and HPLC results it was concluded that strain CY-1 effectively degraded 2,4-D without disturbing the ecosystem of soil indigenous microorganisms.
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Affiliation(s)
- Young-Cheol Chang
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, College of Environmental Technology, Muroran Institute of Technology, 27–1 Mizumoto, Muroran, 050–8585, Japan
- * E-mail:
| | - M. Venkateswar Reddy
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, College of Environmental Technology, Muroran Institute of Technology, 27–1 Mizumoto, Muroran, 050–8585, Japan
| | - Honoka Umemoto
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, College of Environmental Technology, Muroran Institute of Technology, 27–1 Mizumoto, Muroran, 050–8585, Japan
| | - Yuki Sato
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, College of Environmental Technology, Muroran Institute of Technology, 27–1 Mizumoto, Muroran, 050–8585, Japan
| | - Mi-Hye Kang
- Seoul Metropolitan Government Research Institute of Public Health and Environment, 202–3 Yangjae-dong, Seocho-gu, Seoul, 137–893, Republic of Korea
| | - Yuka Yajima
- Graduate School of Medicine, Kyoto University, Yoshidakonoe-cho, Sakyo-ku, Kyoto-shi, Kyoto, 606–8501, Japan
| | - Shintaro Kikuchi
- Course of Chemical and Biological Engineering, Division of Sustainable and Environmental Engineering, College of Environmental Technology, Muroran Institute of Technology, 27–1 Mizumoto, Muroran, 050–8585, Japan
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Venkateswar Reddy M, Mawatari Y, Yajima Y, Seki C, Hoshino T, Chang YC. Poly-3-hydroxybutyrate (PHB) production from alkylphenols, mono and poly-aromatic hydrocarbons using Bacillus sp. CYR1: A new strategy for wealth from waste. Bioresour Technol 2015; 192:711-717. [PMID: 26101960 DOI: 10.1016/j.biortech.2015.06.043] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 06/08/2015] [Accepted: 06/10/2015] [Indexed: 06/04/2023]
Abstract
In the present study five different types of alkylphenols, each of the two different types of mono and poly-aromatic hydrocarbons were selected for degradation, and conversion into poly-3-hydroxybutyrate (PHB) using the Bacillus sp. CYR1. Strain CYR1 showed growth with various toxic organic compounds. Degradation pattern of all the organic compounds at 100 mg/l concentration with or without addition of tween-80 were analyzed using high pressure liquid chromatography (HPLC). Strain CYR1 showed good removal of compounds in the presence of tween-80 within 3 days, but it took 6 days without addition of tween-80. Strain CYR1 showed highest PHB production with phenol (51 ± 5%), naphthalene (42 ± 4%), 4-chlorophenol (32 ± 3%) and 4-nonylphenol (29 ± 3%). The functional groups, structure, and thermal properties of the produced PHB were analyzed. These results denoted that the strain Bacillus sp. CYR1 can be used for conversion of different toxic compounds persistent in wastewaters into useable biological polyesters.
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Affiliation(s)
- M Venkateswar Reddy
- Department of Applied Sciences, College of Environmental Technology, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran 050-8585, Japan
| | - Yasuteru Mawatari
- Research Center for Environmentally Friendly Materials Engineering, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran, Hokkaido 050-8585, Japan
| | - Yuka Yajima
- Graduate School of Medicine, Kyoto University, Yoshidakonoe-cho, Sakyo-ku, Kyoto-shi, Kyoto 606-8501, Japan
| | - Chigusa Seki
- Department of Applied Sciences, College of Environmental Technology, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran 050-8585, Japan
| | - Tamotsu Hoshino
- Biomass Refinery Research Center, National Institute of Advanced Industrial, Sciences and Technology (AIST), 3-11-32 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046, Japan; Bioproduction Research Institute, National Institute of Advanced Industrial Sciences, and Technology (AIST), 2-17-2-1 Tsukisamu-Higashi, Toyohira-ku, Sapporo 062-8517, Japan
| | - Young-Cheol Chang
- Department of Applied Sciences, College of Environmental Technology, Muroran Institute of Technology, 27-1 Mizumoto-cho, Muroran 050-8585, Japan.
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Petnikota S, Rotte NK, Reddy MV, Srikanth VVSS, Chowdari BVR. MgO-decorated few-layered graphene as an anode for li-ion batteries. ACS Appl Mater Interfaces 2015; 7:2301-2309. [PMID: 25559260 DOI: 10.1021/am5064712] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Combustion of magnesium in dry ice and a simple subsequent acid treatment step resulted in a MgO-decorated few-layered graphene (FLG) composite that has a specific surface area of 393 m(2)/g and an average pore volume of 0.9 cm(3)/g. As an anode material in Li-ion batteries, the composite exhibited high reversible capacity and excellent cyclic performance in spite of high first-cycle irreversible capacity loss. A reversible capacity as high as 1052 mAh/g was measured during the first cycle. Even at the end of the 60th cycle, more than 83% of the capacity could be retained. Cyclic voltammetry results indicated pseudocapacitance behavior due to electrochemical absorption and desorption of lithium ions onto graphene. An increase in the capacity has been observed during long-term cycling owing to electrochemical exfoliation of graphene sheets. Owing to its good thermal stability and superior cyclic performance with high reversible capacities, MgO-decked FLG can be an excellent alternative to graphite as an anode material in Li-ion batteries, after suitable modifications.
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Affiliation(s)
- Shaikshavali Petnikota
- School of Engineering Sciences and Technology, University of Hyderabad , Gachibowli, Hyderabad 500046, India
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Hameed AS, Bahiraei H, Reddy MV, Shoushtari MZ, Vittal JJ, Ong CK, Chowdari BVR. Lithium storage properties of pristine and (Mg, Cu) codoped ZnFe2O4 nanoparticles. ACS Appl Mater Interfaces 2014; 6:10744-10753. [PMID: 24912014 DOI: 10.1021/am502605s] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
ZnFe2O4 and MgxCu0.2Zn0.82-xFe1.98O4 (where x = 0.20, 0.25, 0.30, 0.35, and 0.40) nanoparticles were synthesized by sol-gel assisted combustion method. X-ray diffraction (XRD), FTIR spectroscopy, Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) surface area studies were used to characterize the synthesized compounds. ZnFe2O4 and the doped compounds crystallize in Fd3m space group. The lattice parameter of ZnFe2O4 is calculated to be a = 8.448(3) Å, while the doped compounds show a slight decrease in the lattice parameter with an increase in the Mg content. The particle size of all the compositions are in the range of ∼50-80 nm, and the surface area of the compounds are in the range of 11-12 m(2) g(-1). Cyclic voltammetry (CV), galvanostatic cycling, and electrochemical impedance spectroscopy (EIS) studies were used to investigate the electrochemical properties of the different compositions. The as-synthesized samples at 600 °C show large-capacity fading, while the samples reheated at 800 °C show better cycling stability. ZnFe2O4 exhibits a high reversible capacity of 575 mAh g(-1) after 60 cycles at a current density of 100 mA g(-1). Mg0.2Cu0.2Zn0.62Fe1.98O4 shows a similar capacity of 576 mAh g(-1) after 60 cycles with better capacity retention.
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Affiliation(s)
- A Shahul Hameed
- Department of Chemistry, National University of Singapore , Singapore 117543
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Goh BM, Wang Y, Reddy MV, Ding YL, Lu L, Bunker C, Loh KP. Filling the voids of graphene foam with graphene "eggshell" for improved lithium-ion storage. ACS Appl Mater Interfaces 2014; 6:9835-9841. [PMID: 24857682 DOI: 10.1021/am5022655] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Highly porous, N-doped graphene foam is synthesized by chemical vapor deposition process on nickel foam. The voids of the graphene foam can be filled with curved graphene sheets by impregnating the nickel foam template with micrometer-sized nickel powder. Subsequent etching of nickel produces a graphene "eggshells"-in-graphene foam structure. The reversible capacity of such graphene foam when used as anode in lithium ion battery is improved by the presence of graphene "eggshells", as compared to the unfilled foam. The improvement is attributed to the higher rate of lithium diffusion, better buffering of strain associated with lithiation/delithiation and higher volumetric energy density of the unique eggshell-in-graphene foam structure.
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Affiliation(s)
- Bee-Min Goh
- Department of Chemistry, Graphene Research Centre, National University of Singapore , 3 Science Drive 3, Singapore 117543, Singapore
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Amulya K, Reddy MV, Mohan SV. Acidogenic spent wash valorization through polyhydroxyalkanoate (PHA) synthesis coupled with fermentative biohydrogen production. Bioresour Technol 2014; 158:336-342. [PMID: 24637295 DOI: 10.1016/j.biortech.2014.02.026] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2013] [Revised: 02/03/2014] [Accepted: 02/08/2014] [Indexed: 06/03/2023]
Abstract
The production of polyhydroxyalkanoates (PHAs) by Bacillus tequilensis biocatalyst using spent wash effluents as substrate was evaluated to increase the versatility of the existing PHA production process and reduce production cost. In this study, spent wash was used as a substrate for biohydrogen (H2) production and the resulting acidogenic effluents were subsequently employed as substrate for PHA production. Maximum H2 production of 39.8L and maximum PHA accumulation of 40% dry cell weight was attained. Good substrate removal associated with decrement in acidification (53% to 15%) indicates that the VFA generated were effectively utilized for PHA production. The PHA composition showed presence of copolymer [P (3HB-co-3HV)] with varying contents of hydroxybutyrate and hydroxyvalerate. The results obtained suggest that the use of spent wash effluents as substrate can considerably reduce the production cost of PHA with simultaneous waste valorization. PHA synthesis with B. tequilensis and spent wash effluents is reported for the first time.
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Affiliation(s)
- K Amulya
- Bioengineering and Environmental Centre (BEEC), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India
| | - M Venkateswar Reddy
- Bioengineering and Environmental Centre (BEEC), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India
| | - S Venkata Mohan
- Bioengineering and Environmental Centre (BEEC), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 007, India.
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Wu Y, Zhu P, Reddy MV, Chowdari BVR, Ramakrishna S. Maghemite nanoparticles on electrospun CNFs template as prospective lithium-ion battery anode. ACS Appl Mater Interfaces 2014; 6:1951-1958. [PMID: 24383672 DOI: 10.1021/am404939q] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
In this work, maghemite (γ-Fe2O3) nanoparticles were uniformly coated on carbon nanofibers (CNFs) by a hybrid synthesis procedure combining an electrospinning technique and hydrothermal method. Polyacrylonitrile nanofibers fabricated by the electrospinning technique serve as a robust support for iron oxide precursors during the hydrothermal process and successfully limit the aggregation of nanoparticles at the following carbonization step. The best materials were optimized under a carbonization condition of 600 °C for 12 h. X-ray diffraction and electron microscopy studies confirm the formation of a maghemite structure standing on the surface of CNFs. The average size of γ-Fe2O3 nanoparticles is below 100 nm, whereas CNFs are ∼150 nm in diameter. In comparison with aggregated bare iron oxide nanoparticles, the as-prepared carbon-maghemite nanofibers exhibit a higher surface area and greatly improved electrochemical performance (>830 mAh g(-1) at 50 mA g(-1) for 40 cycles and high rate capacity up to 5 A g(-1) in the voltage range of 0.005-3 V vs Li). The greatly enhanced electrochemical performance is attributed to the unique one-dimensional nanostructure and the limited aggregation of nanoparticles.
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Affiliation(s)
- Yongzhi Wu
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore (NUS) , Singapore 119260
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Reddy MV, Prithvi G, Loh KP, Chowdari BVR. Li storage and impedance spectroscopy studies on Co3O4, CoO, and CoN for Li-ion batteries. ACS Appl Mater Interfaces 2014; 6:680-690. [PMID: 24325322 DOI: 10.1021/am4047552] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The compounds, CoN, CoO, and Co3O4 were prepared in the form of nano-rod/particles and we investigated the Li-cycling properties, and their use as an anode material. The urea combustion method, nitridation, and carbothermal reduction methods were adopted to prepare Co3O4, CoN, and CoO, respectively. X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and the Brunauer-Emmett-Teller (BET) surface and density methods were used to characterise the materials. Cyclic voltammetry (CV) was performed and galvanostatic cycling tests were also conducted up to 60-70 cycles. The observed reversible capacity of all compounds is of the increasing order CoO, Co3O4, CoN and all compounds showed negligible capacity fading. CoO allows for Li2O and Co metal to form during the discharge cycle, allowing for a high theoretical capacity of 715 mA h g(-1). Co3O4 allows for 4 Li2O and 3Co to form, and has a theoretical capacity of 890 mAhg(-1). CoN is the best anode material of the three because the nitrogen allows for Li3N and Co to form, resulting in an even higher theoretical capacity of 1100 mAhg(-1) due to the Li3N and Co metal formation. Irrespective of morphology the charge profiles of all three compounds showed a major plateaux ~2.0 V vs. Li and potential values are almost unchanged irrespective of crystal structure. Electrochemical impedance spectroscopy (EIS) was performed to understand variation resistance and capacitance values.
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Affiliation(s)
- M V Reddy
- Department of Physics, Solid State Ionics & Advanced Batteries Lab, §Department of Chemistry, Graphene Research Center, and ⊥Departments of Materials Science & Engineering, National University of Singapore , Singapore 117542
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Wu Y, Reddy MV, Chowdari BVR, Ramakrishna S. Long-term cycling studies on electrospun carbon nanofibers as anode material for lithium ion batteries. ACS Appl Mater Interfaces 2013; 5:12175-84. [PMID: 24171411 DOI: 10.1021/am404216j] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Electrospun carbon nanofibers (CNF) have been prepared at different calcination temperatures for a prolonged time (12 h) derived from electrospun polyacrylonitrile (PAN) membranes. They are studied as anode materials in lithium ion batteries due to their high reversible capacity, improved long-term cycle performance, and good rate capacity. The fibrous morphologies of fresh electrodes and tested samples for more than 550 cycles have been compared; cyclic voltammogram (CV) has also been studied to understand the lithium intercalation/deintercalation mechanism of 1D nanomaterials. CNFs demonstrate interesting galvanostatic performance with fading capacity after the first few cycles, and the capacity increases during long-term cycling. The increasing capacity is observed accompanied by volumetric expansion on the nanofibers' edge. Results of rate capacity have also been explored for all CNF samples, and their stable electrochemical performances are further analyzed by the galvanostatic intermittent titration technique (GITT) and electrochemical impedance spectroscopy (EIS). CNF carbonized at 800 °C is found to have a larger lithium ion storage ability and better cyclic stability than that carbonized at 600 and 1000 °C.
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Affiliation(s)
- Yongzhi Wu
- NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore (NUS) , Singapore 119260
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Cherian CT, Sundaramurthy J, Reddy MV, Suresh Kumar P, Mani K, Pliszka D, Sow CH, Ramakrishna S, Chowdari BVR. Morphologically robust NiFe2O4 nanofibers as high capacity Li-ion battery anode material. ACS Appl Mater Interfaces 2013; 5:9957-9963. [PMID: 24099146 DOI: 10.1021/am401779p] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In this work, the electrochemical performance of NiFe2O4 nanofibers synthesized by an electrospinning approach have been discussed in detail. Lithium storage properties of nanofibers are evaluated and compared with NiFe2O4 nanoparticles by galvanostatic cycling and cyclic voltammetry studies, both in half-cell configurations. Nanofibers exhibit a higher charge-storage capacity of 1000 mAh g(-1) even after 100 cycles with high Coulmbic efficiency of 100% between 10 and 100 cycles. Ex situ microscopy studies confirmed that cycled nanofiber electrodes maintained the morphology and remained intact even after 100 charge-discharge cycles. The NiFe2O4 nanofiber electrode does not experience any structural stress and eventual pulverisation during lithium cycling and hence provides an efficient electron conducting pathway. The excellent electrochemical performance of NiFe2O4 nanofibers is due to the unique porous morphology of continuous nanofibers.
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Affiliation(s)
- Christie Thomas Cherian
- Department of Physics, National University of Singapore , 2 Science Drive 3, Singapore 117551
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Reddy MV, Wen BLW, Loh KP, Chowdari BVR. Energy storage studies on InVO4 as high performance anode material for Li-ion batteries. ACS Appl Mater Interfaces 2013; 5:7777-7785. [PMID: 23869790 DOI: 10.1021/am401501a] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
InVO4 has attracted much attention as an anode material due to its high theoretical capacity. However, the effect of preparation methods and conditions on morphology and energy storage characteristic has not been extensively investigated and will be explored in this project. InVO4 anode material was prepared using five different preparation methods: solid state, urea combustion, precipitation, ball-milling, and polymer precursor methods. Morphology and physical properties of InVO4 were then analyzed using X-ray diffraction (XRD), scanning electron microscope (SEM), and Brunauer-Emmett-Teller (BET) surface area method. XRD patterns showed that orthorhombic phased InVO4 was synthesized. Small amounts of impurities were observed in methods II, III, and V using XRD patterns. BET surface area ranged from 0.49 to 9.28 m(2) g(-1). SEM images showed slight differences in the InVO4 nanosized crystalline structures with respect to preparation methods and conditions. Energy storage studies showed that, among all the preparation methods, the urea combustion method produced the best electrochemical results, with negligible capacity fading between the 2nd and 50th cycles and high capacity of 1241 mA h g(-1) at the end of the 20th cycle, close to the theoretical capacity value. Precipitation method also showed good performance, with capacity fading (14%) and capacity of 1002 mA h g(-1) at the 20th cycle. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) was then used to determine the reaction mechanisms of InVO4.
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Affiliation(s)
- M V Reddy
- Department of Physics, Solid State Ionics/Advanced Batteries Lab, National University of Singapore, Singapore 117542.
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Cherian CT, Zheng M, Reddy MV, Chowdari BVR, Sow CH. Zn2SnO4 nanowires versus nanoplates: electrochemical performance and morphological evolution during Li-cycling. ACS Appl Mater Interfaces 2013; 5:6054-60. [PMID: 23738585 DOI: 10.1021/am400802j] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Zn2SnO4 nanowires have been synthesized directly on stainless steel substrate without any buffer layers by the vapor transport method. The structural and morphological properties are investigated by means of X-ray diffraction (XRD) and transmission electron microscopy (TEM). The electrochemical performance of Zn2SnO4 nanowires is examined by galvanostatic cycling and cyclic voltammetry (CV) measurements in two different voltage windows, 0.005-3 and 0.005-1.5 V vs Li and compared to that of Zn2SnO4 nanoplates prepared by hydrothermal method. Galvanostatic cycling studies of Zn2SnO4 nanowires in the voltage range 0.005-3 V, at a current of 120 mA g(-1), show a reversible capacity of 1000 (±5) mAh g(-1) with almost stable capacity for first 10 cycles, which thereafter fades to 695 mAh g(-1) by 60 cycles. Upon cycling in the voltage range 0.005-1.5 V vs Li, a stable, reversible capacity of 680 (±5) mAh g(-1) is observed for first 10 cycles with a capacity retention of 58% between 10-50 cycles. On the other hand, Zn2SnO4 nanoplates show drastic capacity fading up to 10 cycles and then showed a capacity retention of 80% and 70% between 10 and 50 cycles when cycled in the voltage range 0.005-1.5 and 0.005-3 V, respectively. The structural and morphological evolutions during cycling and their implications on the Li-cycling behavior of Zn2SnO4 nanowires are examined. The effect of the choice of voltage range and initial morphology of the active material on the Li-cycleabilty is also elucidated.
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Reddy MV, Yu C, Jiahuan F, Loh KP, Chowdari BVR. Li-cycling properties of molten salt method prepared nano/submicrometer and micrometer-sized CuO for lithium batteries. ACS Appl Mater Interfaces 2013; 5:4361-4366. [PMID: 23621356 DOI: 10.1021/am400579q] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
We report the synthesis of CuO material by molten salt method at a temperature range, 280 to 950 °C for 3 h in air. This report includes studies on the effect of morphology, crystal structure and electrochemical properties of CuO prepared at different temperatures. Obtained CuO was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) surface area methods. Samples prepared at ≥410 °C showed a single-phase material with a lattice parameter value of a = 4.69 Å, b = 3.43 Å, c = 5.13 Å and surface area values are in the range 1.0-17.0 m(2) g(-1). Electrochemical properties were evaluated via cyclic voltammetry (CV) and galvanostatic cycling studies. CV studies showed a minor difference in the peak potentials depending on preparation temperature and all compounds exhibit a main anodic peak at ~2.45 V and cathodic peaks at ~0.85 V and ~1.25 V vs Li. CuO prepared at 750 °C showed high and stable capacity of ~620 mA h g(-1) at the end of 40th cycle.
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Affiliation(s)
- M V Reddy
- Department of Physics, Solid State Ionics & Advanced Batteries Lab, National University of Singapore, Singapore.
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Das B, Reddy MV, Chowdari BVR. X-ray absorption spectroscopy and energy storage of Ni-doped cobalt nitride, (Ni(0.33)Co(0.67))N, prepared by a simple synthesis route. Nanoscale 2013; 5:1961-1966. [PMID: 23360912 DOI: 10.1039/c2nr33675h] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Metal nitride (Ni(0.33)Co(0.67))N nanoparticles are prepared by nitridation using NiCo(2)O(4) as a precursor material by heating at 335 °C for 2 h in flowing NH(3) + N(2) gas and characterized by X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), high resolution-transmission electron microscopy (HR-TEM), along with selective area electron diffraction (SAED) and X-ray absorption spectroscopy (XAS) techniques. The X-ray absorption near edge structure (XANES) at the Co K-edge showed that the oxidation state of cobalt is close to 3+. The (Ni(0.33)Co(0.67))N showed a shift in edge energy towards lower values due to Ni-doping to cobalt site. The Li-storage behaviour of (Ni(0.33)Co(0.67))N nanoparticles was evaluated by galvanostatic cycling and cyclic voltammetry in the cells with Li-metal as counter electrode in the voltage range of 0.005-3.0 V at ambient temperature. When cycled at 250 mA g(-1), the first-cycle reversible capacity of 700 (±5) mA h g(-1) (~1.9 moles of Li) is obtained. It showed an initial decrease in capacity until the 10(th) cycle and a stable capacity of 400 (±5) mA h g(-1) (~1.09 moles of Li) is observed at the end of the 50(th) cycle. Excellent rate capability is also shown when cycling at 500 mA g(-1) (up to 50 cycles). The materials showed excellent Li-ion insertion/extraction, with the coulombic efficiency reaching almost 99% in the range of 10-50 cycles. The average charge and discharge potentials are ~2.03 and ~1.0 V, respectively for the decomposition/formation of Li(3)N as determined by electroanalytical techniques.
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Affiliation(s)
- B Das
- Department of Physics, National University of Singapore, Singapore 117542
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Cherian CT, Reddy MV, Haur SC, Chowdari BVR. Interconnected network of CoMoO₄ submicrometer particles as high capacity anode material for lithium ion batteries. ACS Appl Mater Interfaces 2013; 5:918-923. [PMID: 23276066 DOI: 10.1021/am302583c] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Interconnected networks of CoMoO(4) submicrometer particles are prepared by thermolysis of polymer matrix based metal precursor solution. The material exhibited a high reversible capacity of 990 (±10) mAh g(-1) at a current density of 100 mA g(-1), with 100% capacity retention between 5 and 50 cycles. The improved electrochemical performance of CoMoO(4) submicrometer particles with interconnected network like morphology makes it promising as a high-capacity anode material for rechargeable lithium ion batteries.
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Affiliation(s)
- Christie T Cherian
- Department of Physics, National University of Singapore, Singapore, 117551
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Venkata Mohan S, Venkateswar Reddy M. Optimization of critical factors to enhance polyhydroxyalkanoates (PHA) synthesis by mixed culture using Taguchi design of experimental methodology. Bioresour Technol 2013; 128:409-416. [PMID: 23201522 DOI: 10.1016/j.biortech.2012.10.037] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Revised: 10/09/2012] [Accepted: 10/10/2012] [Indexed: 05/26/2023]
Abstract
Optimizing different factors is crucial for enhancement of mixed culture bioplastics (polyhydroxyalkanoates (PHA)) production. Design of experimental (DOE) methodology using Taguchi orthogonal array (OA) was applied to evaluate the influence and specific function of eight important factors (iron, glucose concentration, VFA concentration, VFA composition, nitrogen concentration, phosphorous concentration, pH, and microenvironment) on the bioplastics production. Three levels of factor (2(1) × 3(7)) variation were considered with symbolic arrays of experimental matrix [L(18)-18 experimental trails]. All the factors were assigned with three levels except iron concentration (2(1)). Among all the factors, microenvironment influenced bioplastics production substantially (contributing 81%), followed by pH (11%) and glucose concentration (2.5%). Validation experiments were performed with the obtained optimum conditions which resulted in improved PHA production. Good substrate degradation (as COD) of 68% was registered during PHA production. Dehydrogenase and phosphatase enzymatic activities were monitored during process operation.
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Affiliation(s)
- S Venkata Mohan
- Bioengineering and Environmental Centre, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 607, India.
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Srikanth S, Reddy MV, Mohan SV. Microaerophilic microenvironment at biocathode enhances electrogenesis with simultaneous synthesis of polyhydroxyalkanoates (PHA) in bioelectrochemical system (BES). Bioresour Technol 2012; 125:291-299. [PMID: 23037883 DOI: 10.1016/j.biortech.2012.08.060] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 08/13/2012] [Accepted: 08/15/2012] [Indexed: 06/01/2023]
Abstract
Microaerophilic microenvironment at biocathode was evaluated for electrogenesis along with the polyhydroxyalkanoates (PHA) accumulation in bio-electrochemical system (BES). The electrogenic activity (512 mV; 15.2 mW/m(2)) was extended for longer periods (144 h) which might be attributed to the lowering of losses due to the controlled microbial metabolism. Growth limiting stress at cathode due to lower oxygen levels and its effective utilization by the protons and electrons coming from anode, might have diverted the microbial metabolism towards PHA synthesis instead of oxidation. PHA accumulation (19% of dry cell weight (DCW)) was observed with higher hydroxy butyrate (HB) (89%) concentration at 48 th h in the cathodic biocatalyst and was re-utilized by the end of experiment. Bio-electro kinetics studied through voltammetry and Tafel analysis further supported the observed electrogenesis in microaerophilic reduction microenvironment, in terms of redox catalytic currents, Tafel slopes, exchange current densities and polarization resistance.
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Affiliation(s)
- S Srikanth
- Bioengineering and Environmental Centre (BEEC), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 607, India
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Venkateswar Reddy M, Nikhil GN, Venkata Mohan S, Swamy YV, Sarma PN. Pseudomonas otitidis as a potential biocatalyst for polyhydroxyalkanoates (PHA) synthesis using synthetic wastewater and acidogenic effluents. Bioresour Technol 2012; 123:471-479. [PMID: 22940357 DOI: 10.1016/j.biortech.2012.07.077] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 07/16/2012] [Accepted: 07/22/2012] [Indexed: 06/01/2023]
Abstract
Polyhydroxyalkanoates (PHA) production using Pseudomonas otitidis, a newly isolated strain from PHA producing bioreactor was investigated using synthetic acids (SA) and acidogenic effluents (AE) from biohydrogen reactor at different organic loading rates (OLRs). P. otitidis showed ability to grow and accumulate PHA, with simultaneous waste remediation. AE showed less PHA production (54%, OLR3), than SA (58%, OLR2). PHA composition showed co-polymer, poly-3(hydroxy butyrate-co-hydroxy valerate), P3(HB-co-HV). Bioprocess evaluation and enzymatic activities showed good correlation with PHA production. Kinetic studies on the growth of bacteria using different models at varying OLR were substantiated with PHA production. High substrate removal was registered at OLR1 (SA, 87%; AE, 82%). AE could be used as an alternative for pure substrates keeping in view of their high cost.
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Affiliation(s)
- M Venkateswar Reddy
- Bioengineering and Environmental Centre (BEEC), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 607, India
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Gupta S, Singh KK, Vyas VJ, Chaturvedi VN, Reddy MV, Harinath BC. Assessment of oxidative stress and effect of antioxidant supplementation during radiotherapy in carcinoma of upper digestive tract. Indian J Clin Biochem 2012; 15:52-5. [PMID: 23105239 DOI: 10.1007/bf02873549] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Oxidative stress was studied by estimating plasma levels of malondialdehyde (MDA), beta carotene, vitamin E and erythrocytic superoxide dismutase(E-SOD) activity in 50 cases of carcinoma of upper digestive tract which included carcinoma of oral cavity, pharynx and oesophagus. While plasma MDA level was found to be increased (3.5±1.0 nmole/ml), a significant decrease in beta carotene (81.2±14.5mg%), vitamin E (8.5±1.1 mg/L) level and E-SOD activity (657.0±80.6 U/G Hb) were observed in carcinoma of upper digestive tract. Patients were treated with radiotherapy which itself was toxic enough and produced its deleterious effects by generation of reactive oxygen species (ROS). As antioxdiants can detoxify ROS, beneficial effect if any, of antioxidant administration during radiotherapy was studied in two groups of patients, group A (n=5, supplemented with antioxidants) and group B (n=5, without antioxidant supplementation). Plasma MDA level was found to be elevated in both the groups but the increase in group B was significant, compared to pretreatment level. Further, body weight was found to be significantly decreased in group B patients, which was maintained in group A patients. Moreover, group A patients showed significant elevation in beta carotene concentration, thus showing beneficial effect of administration of antioxidants during radiotherapy without disturbing the desirable therapeutic effect of radiotherapy.
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Affiliation(s)
- S Gupta
- Jamnalal Bajaj Tropical Disease Research Centre, Mahatma Gandhi Institute of Medical Sciences, Sevagram, 442102 Wardha
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Harinath BC, Reddy MV, Bhunia B, Bhandari YP, Mehta VK, Chaturvedi P, Prajapati NC, Gupta RK. Filaria associated clinical manifestations in children in an endemic area and morbidity control by immunomonitoring and optimal DEC therapy: Sevagram experience. Indian J Clin Biochem 2012; 15:118-26. [PMID: 23105275 DOI: 10.1007/bf02867551] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Lymphatic filariasis is a major public health problem in India with 412 million people living in bancroftian endemic areas and is a major cause of clinical morbidity. Twenty million people are reported to suffer from chronic disease manifestations such as lymphoedema, hydrocele or elephantiasis. At least twice the number have been shown to suffer from acute and occult filarial infections in an endemic area without diagnosis. Due to non-availability of suitable diagnostic test for confirming filaria aetiology other than parasitological examination, no significant study on filariasis in children has been reported earlier. Studies in our laboratory for more than a decade showed usefulness of microfilarial excretory-secretory antigen in confirming filarial aetiology in acute and occult infections in adults as well as in children. This study reports acute and atypical manifestations such as lymphadenopathy, asthmatic bronchitis, pulmonary eosinophilia, mono-arthritis, recurrent URI, pneumonia, nutritional anemia, pain in abdomen etc. in children living in filaria endemic area having no microfilaraemia but showing filaria aetiology by immunomonitoring for the presence of antibody or antigen and responding to optimal DEC therapy.
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Affiliation(s)
- B C Harinath
- JB Tropical Disease Research Centre and Department of Biochemistry, Mahatma Gandhi Institute of Medical Sciences, 442102 Sevagram, (Wardha) India
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Nair ER, Kumar S, Reddy MV, Harinath BC. Mycobacterium tuberculosis H(37)Ra ESAS-7-An excretory-secretory antigen fraction of immunodiagnostic potential in pulmonary tuberculosis. Indian J Clin Biochem 2012; 13:98-105. [PMID: 23105189 DOI: 10.1007/bf02867870] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
A mycobacterial excretory-secretory protein fraction ESAS-7 purified by 50% ammonium sulphate precipitation followed by SDS-PAGE fractionation was evaluated by penicillinase enzyme linked immuno-sorbent assay (ELISA) for its sensitivity and specificity in the diagnosis of pulmonary tuberculosis. At a "cut off" serum dilution of 600, 38 (90%) of 42 sera from bacteriologically confirmed tuberculosis cases, 15 (100%) of 15 sera from bacteriogically negative but anti tubercular therapy (ATT) responded cases, 3 (7%) of 43 sera from normal healthy subjects and 4 (8%) of 48 sera from non tuberculous disease control cases gave positive reaction for tubercular antibody to ESAS-7 antigen fraction containing predominantly 33-kDa protein with a sensitivity of 90% in bacteriologically confirmed cases and specificity of 92%. Further, this diagnostic assay using the ESAS-7 antigen is more sensitive requiring as little as one nanogram antigen per test compared to use of 100 nanogram EST-6 antigen reported earlier. Thus use of ESAS-7 antigen for antibody detection has good diagnostic potential with improved specificity in pulmonary tuberculosis.
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Affiliation(s)
- E R Nair
- Jamnalal Bajaj Tropical Disease Research Centre and Department of Biochemistry, Mahatma Gandhi Institute of Medical Sciences, Sevagram, 442 102 Wardha
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Zhu P, Reddy MV, Wu Y, Peng S, Yang S, Nair AS, Loh KP, Chowdari BVR, Ramakrishna S. Mesoporous SnO2 agglomerates with hierarchical structures as an efficient dual-functional material for dye-sensitized solar cells. Chem Commun (Camb) 2012; 48:10865-7. [PMID: 23023087 DOI: 10.1039/c2cc36049g] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mesoporous SnO(2) agglomerates with hierarchical structures and a high surface area were fabricated through a molten salt method. The SnO(2) demonstrated high photoelectric conversion efficiencies of 3.05% and 6.23% (with TiCl(4) treatment) in dye-sensitized solar cells, which are attributed to its dual functionality of providing high dye-loading and efficient light scattering.
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Affiliation(s)
- Peining Zhu
- Department of Mechanical Engineering, National University of Singapore, Singapore 117574
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Venkateswar Reddy M, Venkata Mohan S. Effect of substrate load and nutrients concentration on the polyhydroxyalkanoates (PHA) production using mixed consortia through wastewater treatment. Bioresour Technol 2012; 114:573-82. [PMID: 22456236 DOI: 10.1016/j.biortech.2012.02.127] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2011] [Revised: 02/21/2012] [Accepted: 02/24/2012] [Indexed: 05/06/2023]
Abstract
Production of biodegradable plastics in the form of polyhydroxyalkanoates (PHA) especially from renewable substrates is gaining interest. The present work mainly aims to investigate the influence of substrate load and nutrient concentration (nitrogen and phosphorous) on PHA production using wastewater as substrate and mixed culture as biocatalyst. PHA accumulation was high at higher substrate load [OLR3, 40.3% of dry cell weight (DCW)], low nitrogen (N(1), 45.1% DCW) and low phosphorous (P(1), 54.2% DCW) conditions. With optimized nutrient conditions production efficiency increased by 14%. Fractional composition of PHA showed co-polymer [poly(β-OH) butyrate-co-poly(β-OH) valerate, P3(HB-co-HV)] contains PHB (88%) in more concentration compared to PHV (8%). Dehydrogenase and phosphatase enzymatic activities were monitored during process operation. Good substrate degradation (as COD) of 75% was registered during PHA production. The phylogenetic profile of 16S rRNA sequencing showed the dominance of Firmicutes (71.4%) and Proteobacteria (28.6%), which are known to involve in PHA accumulation and waste treatment.
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Affiliation(s)
- M Venkateswar Reddy
- Bioengineering and Environmental Centre (BEEC), CSIR-Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 607, India
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Kumar AK, Reddy MV, Chandrasekhar K, Srikanth S, Mohan SV. Endocrine disruptive estrogens role in electron transfer: bio-electrochemical remediation with microbial mediated electrogenesis. Bioresour Technol 2012; 104:547-556. [PMID: 22137274 DOI: 10.1016/j.biortech.2011.10.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Revised: 10/12/2011] [Accepted: 10/12/2011] [Indexed: 05/31/2023]
Abstract
Bioremediation of selected endocrine disrupting compounds (EDCs)/estrogens viz. estriol (E3) and ethynylestradiol (EE2) was evaluated in bio-electrochemical treatment (BET) system with simultaneous power generation. Estrogens supplementation along with wastewater documented enhanced electrogenic activity indicating their function in electron transfer between biocatalyst and anode as electron shuttler. EE2 addition showed more positive impact on the electrogenic activity compared to E3 supplementation. Higher estrogen concentration showed inhibitory effect on the BET performance. Poising potential during start up phase showed a marginal influence on the power output. The electrons generated during substrate degradation might have been utilized for the EDCs break down. Fuel cell behavior and anodic oxidation potential supported the observed electrogenic activity with the function of estrogens removal. Voltammetric profiles, dehydrogenase and phosphatase enzyme activities were also found to be in agreement with the power generation, electron discharge and estrogens removal.
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Affiliation(s)
- A Kiran Kumar
- IICT-CCMB Dispensary, Indian Institute of Chemical Technology (CSIR-IICT), Hyderabad 500 607, India
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Reddy MV, Mohan SV. Influence of aerobic and anoxic microenvironments on polyhydroxyalkanoates (PHA) production from food waste and acidogenic effluents using aerobic consortia. Bioresour Technol 2012; 103:313-21. [PMID: 22055090 DOI: 10.1016/j.biortech.2011.09.040] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2011] [Revised: 09/09/2011] [Accepted: 09/10/2011] [Indexed: 05/11/2023]
Abstract
The functional role of aerobic and anoxic microenvironments on polyhydroxyalkanoates (PHA) production using food waste (UFW) and effluents from acidogenic biohydrogen production process (FFW) were studied employing aerobic mixed culture as biocatalyst. Anoxic microenvironment documented higher PHA production, while aerobic microenvironment showed higher substrate degradation. FFW showed higher PHA accumulation (39.6%) than UFW (35.6%) due to ready availability of precursors (fatty acids). Higher fraction of poly-3-hydroxy butyrate (PHB) was observed compared to poly-3-hydroxy valerate (PHV) in the accumulated PHA in the form of co-polymer [P3(HB-co-HV)]. Dehydrogenase, phosphatase and protease enzymatic activities were monitored during process operation. Integration with fermentative biohydrogen production yielded additional substrate degradation under both aerobic (78%) and anoxic (72%) microenvironments apart from PHA production. Microbial community analysis documented the presence of aerobic and facultative organisms capable of producing PHA. Integration strategy showed feasibility of producing hydrogen along with PHA by consuming fatty acids generated during acidogenic process in association with increased treatment efficiency.
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Affiliation(s)
- M Venkateswar Reddy
- Bioengineering and Environmental Centre (BEEC), Indian Institute of Chemical Technology (IICT), Hyderabad 500 607, India
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Subramanian S, Ayyasamy S, Selvin PC, Reddy MV, Chowdari BVR, Heller N, Dorai A, Muthusamy H. Synthesis of Li(1+x)V3O8 by chemical route and its characterization. J Nanosci Nanotechnol 2012; 12:737-742. [PMID: 22524049 DOI: 10.1166/jnn.2012.5362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Lithium trivanadate (Li(1+x)V3O8) nanorods have been synthesized by the simple polymer precursor route using the polymer, polyvinyl pyrrolidone (PVP) as the complexing agent. Thermal behavior of the precursor has been studied by the differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and differential thermal analysis (DTA) techniques. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) studies confirm the formation of the compound. High resolution scanning electron microscopy (HRSEM) analysis reveals the synthesized Li1.2V3O8 particles to be nanorods with an average diameter of 50 nm.
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Reddy MV, Devi MP, Chandrasekhar K, Goud RK, Mohan SV. Aerobic remediation of petroleum sludge through soil supplementation: microbial community analysis. J Hazard Mater 2011; 197:80-87. [PMID: 22019106 DOI: 10.1016/j.jhazmat.2011.09.061] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 08/08/2011] [Accepted: 09/15/2011] [Indexed: 05/31/2023]
Abstract
The effect of soil concentration on the aerobic degradation of real-field petroleum sludge was studied in slurry phase reactor. Total petroleum hydrocarbons (TPH) and polycyclic aromatic hydrocarbons (PAHs) showed effective removal but found to depend on the soil concentration. Aromatic fraction (48.12%) documented effective degradation compared to aliphatics (47.31%), NSO (28.69%) and asphaltenes (26.66%). PAHs profile showed efficient degradation of twelve individual aromatic compounds where lower ring compounds showed relatively higher degradation efficiency compared to the higher ring compounds. The redox behaviour and dehydrogenase activity showed a linear increment with the degradation pattern. Microbial community composition and changes during bioremediation were studied using denaturing gradient gel electrophoresis (DGGE). Among the 12 organisms identified, Proteobacteria was found to be dominant representing 50% of the total population (25% of γ-proteobacteria; 16.6% of β-proteobacteria; 8.3% of α-proteobacteria), while 33.3% were of uncultured bacteria and 16.6% were of firmicutes.
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Affiliation(s)
- M Venkateswar Reddy
- Bioengineering and Environmental Centre (BEEC), Indian Institute of Chemical Technology CSIR-IICT, Hyderabad, India
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Reddy MV, Chandrasekhar K, Mohan SV. Influence of carbohydrates and proteins concentration on fermentative hydrogen production using canteen based waste under acidophilic microenvironment. J Biotechnol 2011; 155:387-95. [DOI: 10.1016/j.jbiotec.2011.07.030] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 06/29/2011] [Accepted: 07/21/2011] [Indexed: 11/25/2022]
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Venkata Mohan S, Reddy MV, Subhash GV, Sarma PN. Fermentative effluents from hydrogen producing bioreactor as substrate for poly(beta-OH) butyrate production with simultaneous treatment: an integrated approach. Bioresour Technol 2010; 101:9382-9386. [PMID: 20667721 DOI: 10.1016/j.biortech.2010.06.109] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2010] [Revised: 06/11/2010] [Accepted: 06/23/2010] [Indexed: 05/29/2023]
Abstract
The feasibility of bioplastics production as poly(beta-OH)butyrate (PHB) was studied with individual volatile fatty acids (VFA) and acid-rich effluents from a biohydrogen producing reactor (HBR) as primary substrates employing aerobic consortia as biocatalyst under anoxic microenvironment. Butyrate as substrate showed higher PHB productivity (33%) followed by acetate (32%), acids mixture (16%) and propionate (11%) among synthetic VFA studied. Acid-rich effluents from HBR yielded higher PHB productivity (25%) especially at lower substrate loading conditions. Decrement observed in PHB production (from 25% to 6%) with increase in substrate load might be due to the presence of high concentration of residual carbon along with acid metabolites. Neutral redox operation showed effective PHB production compared to acidic and basic conditions due to associated higher metabolic activity of the biocatalyst. The integrated approach helped to treat additional COD from acid-rich HBR effluents apart from by-product recovery.
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Affiliation(s)
- S Venkata Mohan
- Bioengineering and Environmental Centre, Indian Institute of Chemical Technology, Hyderabad 500 607, India.
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Reddy MV, Pecquenard B, Vinatier P, Levasseur A. Effect of Substrate Temperature on Morphology and Electrochemical Performance of Radio Frequency Magnetron Sputtered Lithium Nickel Vanadate Films Used as Negative Electrodes for Lithium Microbatteries. J Phys Chem B 2006; 110:4301-6. [PMID: 16509727 DOI: 10.1021/jp0565554] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Lithium nickel vanadate thin films were prepared by radio frequency magnetron sputtering at various substrate temperatures (Ts). These thin films have been investigated as anode electrode material in the use of microbatteries. Films were characterized by Rutherford backscattering spectroscopy, nuclear reaction analysis, Auger electron spectroscopy, glancing-incidence X-ray diffraction analysis, Raman spectroscopy, scanning electron microscopy, atomic force microscopy, and high-resolution transmission electron microscopy techniques. The anodic electrochemical performances of the films have been evaluated by cyclic voltammetry at a scan rate of 1 mV/s and by galvanostatic cycling, with lithium metal as the counter and the reference electrode, and cycled in the range of 0.02-3.0 V at a current density of 75 microA/cm2. Thin films prepared at a Ts of 650 degrees C show a discharge capacity at the 20th cycle of 1100 (+/-10) mAh/g, which exhibited excellent capacity retention with a small capacity fade.
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Affiliation(s)
- M V Reddy
- ICMCB-CNRS/ENSCPB, Université de Bordeaux 1, 33607 Pessac Cedex, France.
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Laws GM, Skopek TR, Reddy MV, Storer RD, Glaab WE. Detection of DNA adducts using a quantitative long PCR technique and the fluorogenic 5' nuclease assay (TaqMan). Mutat Res 2001; 484:3-18. [PMID: 11733068 DOI: 10.1016/s0027-5107(01)00263-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The detection of DNA adducts is an important component in assessing the mutagenic potential of exogenous and endogenous compounds. Here, we report an in vitro quantitative long PCR (XL-PCR) assay to measure DNA adducts in human genomic DNA based on their ability to block and inhibit PCR amplification. Human genomic DNA was exposed to test compounds and then a target sequence was amplified by XL-PCR. The amplified sequence was then quantified using fluorogenic 5' nuclease PCR (TaqMan) and normalized to a solvent-treated control. The extent of DNA adduction was determined based on the reduction in amplification of the target sequence in the treated sample. A 17.7kb beta-globin fragment was chosen as the target sequence for these studies, since preliminary experiments revealed a two-fold increased sensitivity of this target compared to a 10.4kb HPRT fragment for detecting hydrogen peroxide-induced DNA damage. Validation of the XL-PCR assay with various compounds demonstrated the versatility of the assay for detecting a wide range of adducts formed by direct acting or S9-activated mutagens. The same DNA samples were also analyzed using 32P-postlabeling techniques (thin-layer chromatography or high-performance liquid chromatography) to confirm the presence of DNA adducts and estimate their levels. Whereas 32P-postlabeling with nuclease P(1) enrichment was more sensitive for detecting bulky adducts induced by the compounds benzo[a]pyrene, dimethylbenzanthracene, 3-methylindole, indole 3-carbinol, or 2-acetylaminofluorene, the XL-PCR procedure was more sensitive for detecting smaller or labile DNA adducts formed by the compounds methyl methanesulfonate, diethyl nitrosamine, ethylnitrosourea, diepoxybutane, ICR-191, styrene oxide, or aflatoxin B(1). Compounds not expected to form adducts in DNA, such as clofibrate, phenobarbital, chloroform or acetone, did not produce a positive response in the XL-PCR assay. Thus, quantitative XL-PCR provides a rapid, high-throughput assay for detecting DNA damage that complements the existing 32P-postlabeling assay with nuclease P(1) enrichment.
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Affiliation(s)
- G M Laws
- Department of Genetic and Cellular Toxicology, Merck Research Laboratories, WP45-320, West Point, PA 19486, USA
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Rama Rao B, Reddy MV. A note on Goraksanātha and his work Yogadipikā. Bull Indian Inst Hist Med Hyderabad 2001; 12:34-44. [PMID: 11611679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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Alli R, Kulkarni S, Reddy MV, Harinath BC. Evaluation of sevafilachek immunoassays and rapid ICT-filariasis test for detection of bancroftian filariasis. Indian J Clin Biochem 2001; 16:207-10. [PMID: 23105320 DOI: 10.1007/bf02864863] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
A comparative analysis was made on the utility of SEVAFILACHEK-stick based immunoassays and commercially available ICT-filariasis test to detect active infection in different groups of bancroftian filariasis. The SEVAFILACHEK immunoassays were found to be useful to detect filarial infection in microfilaraemia and in a significant number of clinical filarial cases with acute, chronic and occult clinical manifestations. In the clinical cases, microfilariae are not usually detected in peripheral circulation. Employing SEVAFILACHEK assays 6 and 5 of the 7 samples of patients with chronic filarial disease, and 6 and 5 of 6 microfilaraemic cases gave positivity for filarial IgG antibodies and antigen respectively. Four of the 6 occult filarial samples were positive for antibodies and antigen. Filarial antigen was detected by ICT-filariasis test in blood samples of all the 6 microfilariaemic cases, 1 chronic filarial and 2 occult filarial samples. The main advantage of ICT assay is its rapid format and convenience for field use.
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Affiliation(s)
- R Alli
- Department of Biochemistry & JB Tropical Disease Research Centre, MGIMS, 442102 Sevagram(Wardha), Maharashtra India
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Banerjee S, Nair ER, Kumar S, Gangane N, Reddy MV, Harinath BC. Sero-reactivity of two different antigenic protein fractions of M.tb H37Ra excretory-secretory antigen in pulmonary and extra-pulmonary tuberculosis. J Commun Dis 2001; 33:63-71. [PMID: 12170939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/26/2023]
Abstract
Excretory-secretory proteins of Mycobacterium tuberculosis H37Ra, have been of diagnostic interest in pulmonary (PTB) and extrapulmonary tuberculosis (EPTB). Two different excretory-secretory antigenic proteins of M.tbH37Ra viz., EST-DE1 (a 6% TCA soluble and DEAE anion exchange purified antigen) and ESAS-7 (50% ammonium sulphate solubilized and SDS-PAGE fractionated antigen) were studied in stick-indirect penicillinase ELISA for detecting tuberculous IgG antibodies in serum samples of pulmonary as well as extrapulmonary tuberculosis (tuberculous lymphadenopathy (TBLN), tuberculous meningitis (TBM), bone & joint tuberculosis (B&J TB), abdominal tuberculosis (Abd. TB) patients. The ESAS-7 antigen has shown comparatively better seroreactivity (90%) than that of EST-DE1 antigen in pulmonary tuberculosis cases. The overall specificity of 93.2% using ESAS-7 antigen was also found better compared to 86.4% obtained using EST-DE1 antigen. Further, in extra pulmonary tuberculosis group, using ESAS-7 antigen 84% (21/25) of histopathologically confirmed TBLN cases and 90% (9/10) clinically diagnosed and ATT responded TBM cases showed positive reaction for tuberculous IgG antibody. The per cent positivity using EST-DE1 antigen was however comparatively low in TBLN and TBM cases, (76% and 80% respectively). In histopathologically proven bone and joint tuberculosis and abdominal tuberculosis cases EST-DE1 antigen showed better sensitivity of 75% and 83.3% respectively in IgG antibody detection compared to that of ESAS-7 antigen (50% and 66% respectively). From the present study, it can be envisaged that ESAS-7 antigenic fraction has a good potential in the diagnosis of pulmonary and certain extra-pulmonary tuberculosis infection (TBLN & TBM) whereas EST-DE1 was found to be better in detecting specific antibodies in bone & joint and abdominal tuberculosis.
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Affiliation(s)
- S Banerjee
- Jamna Lal Bajaj Tropical Disease Research Centre, Mahatma Gandhi Institute of Medical Sciences, Sevagram, Wardha-442 102, Maharashtra
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