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Saxena RK, Anand S, Guha SK. Diagnosis of Knee Joint Osteoarthritis by Bioelectrical Impedance Plethysmography. Journal of Health and Allied Sciences NU 2022. [DOI: 10.1055/s-0041-1741562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
AbstractDiagnosis of knee joint osteoarthritis (KJO) at early stages can prolong the progression of disabling degenerative ailments. Mostly, diagnosis of KJO is based on patient complaints about difficulty with locomotion and is clinically diagnosed based on gait and features. Classical radiographic and MRI images further validated the presence of KJO. Due to the economic and limited accessibility of the above services in India and neighboring countries, a large number of patients with KJO continue to suffer without a diagnosis. There is a need to develop a cost-effective, quick, simple, non-invasive, and reliable diagnostic technique for the onset of KJO. The present study aims to monitor the conductivity changes and impedance fluctuations using an electrical impedance plethysmograph. Impedance fluctuations recorded in normal and osteoarthritis patients showed marked differences. The analysis of these records can identify early damage to the joint.
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Affiliation(s)
| | - Sneh Anand
- Centre for Biomedical Engineering, Indian Institute of Technology, New Delhi, India
| | - Sujoy Kumar Guha
- Centre for Biomedical Engineering, Indian Institute of Technology, New Delhi, India
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Wijayawardene NN, Hyde KD, Dai DQ, Sánchez-García M, Goto BT, Saxena RK, Erdoğdu M, Selçuk F, Rajeshkumar KC, Aptroot A, Błaszkowski J, Boonyuen N, da Silva GA, de Souza FA, Dong W, Ertz D, Haelewaters D, Jones EBG, Karunarathna SC, Kirk PM, Kukwa M, Kumla J, Leontyev DV, Lumbsch HT, Maharachchikumbura SSN, Marguno F, Martínez-Rodríguez P, Mešić A, Monteiro JS, Oehl F, Pawłowska J, Pem D, Pfliegler WP, Phillips AJL, Pošta A, He MQ, Li JX, Raza M, Sruthi OP, Suetrong S, Suwannarach N, Tedersoo L, Thiyagaraja V, Tibpromma S, Tkalčec Z, Tokarev YS, Wanasinghe DN, Wijesundara DSA, Wimalaseana SDMK, Madrid H, Zhang GQ, Gao Y, Sánchez-Castro I, Tang LZ, Stadler M, Yurkov A, Thines M. Outline of Fungi and fungus-like taxa – 2021. MYCOSPHERE 2022. [DOI: 10.5943/mycosphere/13/1/2] [Citation(s) in RCA: 24] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
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Jahan F, Kumar V, Saxena RK. Distillery effluent as a potential medium for bacterial cellulose production: A biopolymer of great commercial importance. Bioresour Technol 2018; 250:922-926. [PMID: 29249539 DOI: 10.1016/j.biortech.2017.09.094] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [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: 07/18/2017] [Revised: 09/12/2017] [Accepted: 09/15/2017] [Indexed: 06/07/2023]
Abstract
In the present study, an attempt was made to utilize the distillery effluent for the production of bacterial cellulose by a novel bacterial species, Gluconacetobacter oboediens. Maximum bacterial cellulose production of 0.85g/100ml was achieved in crude distillery effluent. The production was successfully scaled up to 1.0L size producing 8.1g of bacterial cellulose. Morphological, structural and thermal characterization of purified bacterial cellulose by SEM, FT-IR and TGA analysis showed that it is pure cellulose having good properties. Henceforth, the present study proved a concept that distillery effluent could be utilized for the production of bacterial cellulose, a biopolymer of immense importance, which in turn may be used for producing different value added products.
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Affiliation(s)
- Firdaus Jahan
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India; Food Safety and Standards Authority of India (FSSAI), FDA Bhawan, New Delhi 110002, India
| | - Vinod Kumar
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India; Center of Innovative and Applied Bioprocessing (CIAB), Sector-81 (Knowledge City), PO Manauli, S.A.S. Nagar, Mohali 140306, Punjab, India
| | - R K Saxena
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India.
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Kumar V, Jahan F, Mahajan RV, Saxena RK. Efficient regioselective acylation of quercetin using Rhizopus oryzae lipase and its potential as antioxidant. Bioresour Technol 2016; 218:1246-1248. [PMID: 27372535 DOI: 10.1016/j.biortech.2016.06.057] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [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: 05/07/2016] [Revised: 06/15/2016] [Accepted: 06/16/2016] [Indexed: 06/06/2023]
Abstract
The present investigation describes the regioselective enzymatic acylation of quercetin with ferulic acid using Rhizopus oryzae lipase. Optimization of reaction parameters resulted in 93.2% yield of the ester synthesized using 750IU of lipase in cyclo-octane at a temperature of 45°C. The reaction was successfully carried out upto 25g scale. The ester synthesized was analyzed by (1)H Nuclear magnetic resonance spectroscopy. The ester synthesized (quercetin ferulate) showed higher antiradical activity as compared to ascorbic acid using the 2,2-diphenyl-1-picrylhydrazyl radical method. These results on enzyme-catalyzed acylation of quercetin might be used to prepare and scale-up other flavonoids derivatives.
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Affiliation(s)
- Vinod Kumar
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India; Center of Innovative and Applied Bioprocessing (CIAB), C-127, IInd Floor, Phase 8, Industrial Area, S.A.S. Nagar, Mohali 160071, Punjab, India
| | - Firdaus Jahan
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India
| | - Richi V Mahajan
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India
| | - Rajendra Kumar Saxena
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India.
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Saran S, Mukherjee S, Dalal J, Saxena RK. High production of erythritol from Candida sorbosivorans SSE-24 and its inhibitory effect on biofilm formation of Streptococcus mutans. Bioresour Technol 2015; 198:31-38. [PMID: 26363499 DOI: 10.1016/j.biortech.2015.08.146] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [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: 07/13/2015] [Revised: 08/27/2015] [Accepted: 08/28/2015] [Indexed: 06/05/2023]
Abstract
Amongst different isolates screened for erythritol production, isolate no. SSE-24 was found to be the best erythritol producer and identified as Candida sorbosivorans SSE-24. Statistical optimization was used to determine the optimum level of the significant variables for maximum erythritol production. The interactive effects of glucose, inoculum level and yeast extract were determined to be significant. The optimum medium composition for erythritol production was 160 g/L glucose, 12 g/L yeast extract, 10% inoculum level and 0.35 g/L FeSO4⋅7H2O. The production of erythritol was successfully scaled up to a 30 L level, where 60.20 g/L of erythritol was produced, with a yield of 0.38 g/g. The fermentation broth was purified by activated charcoal followed by vacuum concentration, ion exchange chromatography and crystallization. Purity of erythritol was further determined by NMR. Significant inhibitory effect of erythritol on growth (>78%) and biofilm formation (40.2%) of Streptococcus mutans enhances the importance of this study.
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Affiliation(s)
- Saurabh Saran
- Technology Based Incubator, Delhi University South Campus, Benito Juarez Road, New Delhi 110021, India
| | - Sanjana Mukherjee
- Department of Microbiology, Delhi University South Campus, Benito Juarez Road, New Delhi 110021, India
| | - Jyotsana Dalal
- Department of Microbiology, Delhi University South Campus, Benito Juarez Road, New Delhi 110021, India
| | - Rajendra Kumar Saxena
- Department of Microbiology, Delhi University South Campus, Benito Juarez Road, New Delhi 110021, India.
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Tripathi P, Rawat G, Yadav S, Saxena RK. Shikimic acid, a base compound for the formulation of swine/avian flu drug: statistical optimization, fed-batch and scale up studies along with its application as an antibacterial agent. Antonie Van Leeuwenhoek 2014; 107:419-31. [PMID: 25563634 DOI: 10.1007/s10482-014-0340-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 11/17/2014] [Indexed: 11/25/2022]
Abstract
The sudden outbreak of swine flu has increased the global demand of shikimic acid which is an industrially interesting compound, as it is used as a key starting material for the synthesis of a neuraminidase inhibitor Tamiflu(®), for the treatment of antiviral infections such as swine flu. Statistical optimization and evaluation of medium components for the production of shikimic acid by Citrobacter freundii is addressed in the present investigation. Plackett-Burman design was applied for the screening of the most significant variables affecting shikimic acid production, where glucose, asparagine, KH2PO4, CaCO3 and agitation rate were the most significant factors. Response surface methodology was also employed to study the interaction among the most significant variables through which shikimic acid production increased to 12.76 g/L. Further, fed-batch studies resulted in the production of 22.32 g/L of shikimic acid. The scalability of the process was also confirmed by running 14 L bioreactor (7.5 L production medium) where 20.12 g/L of shikimic acid was produced. In addition the antibacterial activity of the shikimic acid produced was analysed against four Gram positive and four Gram negative bacteria and it was found to have a greater inhibition effect against the Gram negative bacteria.
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Affiliation(s)
- P Tripathi
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
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Mahajan RV, Kumar V, Rajendran V, Saran S, Ghosh PC, Saxena RK. Purification and characterization of a novel and robust L-asparaginase having low-glutaminase activity from Bacillus licheniformis: in vitro evaluation of anti-cancerous properties. PLoS One 2014; 9:e99037. [PMID: 24905227 PMCID: PMC4048267 DOI: 10.1371/journal.pone.0099037] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [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: 02/24/2014] [Accepted: 05/09/2014] [Indexed: 11/18/2022] Open
Abstract
L-asparaginase having low glutaminase has been a key therapeutic agent in the treatment of acute lymphpoblastic leukemia (A.L.L). In the present study, an extracellular L-asparaginase with low glutaminase activity, produced by Bacillus licheniformis was purified to homogeneity. Protein was found to be a homotetramer of 134.8 KDa with monomeric size of 33.7 KDa and very specific for its natural substrate i.e. L-asparagine. The activity of purified L-asparaginase enhanced in presence of cations including Na+ and K+, whereas it was moderately inhibited in the presence of divalent cations and thiol group blocking reagents. The purified enzyme was maximally active over the range of pH 6.0 to 10.0 and temperature of 40°C and enzyme was stable maximum at pH 9.0 and -20°C. CD spectra of L-asparaginase predicted the enzyme to consist of 63.05% α-helix and 3.29% β-sheets in its native form with T222 of 58°C. Fluorescent spectroscopy showed the protein to be stable even in the presence of more than 3 M GdHCl. Kinetic parameters Km, Vmax and kcat of purified enzyme were found as 1.4×10(-5) M, 4.03 IU and 2.68×10(3) s(-1), respectively. The purified L-asparaginase had cytotoxic activity against various cancerous cell lines viz. Jurkat clone E6-1, MCF-7 and K-562 with IC50 of 0.22 IU, 0.78 IU and 0.153 IU respectively. However the enzyme had no toxic effect on human erythrocytes and CHO cell lines hence should be considered potential candidate for further pharmaceutical use as an anticancer drug.
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Affiliation(s)
- Richi V. Mahajan
- Department of Microbiology, University of Delhi South Campus, New Delhi, Delhi, India
| | - Vinod Kumar
- Department of Microbiology, University of Delhi South Campus, New Delhi, Delhi, India
| | - Vinoth Rajendran
- Department of Biochemistry, University of Delhi South Campus, New Delhi, Delhi, India
| | - Saurabh Saran
- Technology Based Incubator, University of Delhi South Campus, New Delhi, Delhi, India
| | - Prahlad C. Ghosh
- Department of Biochemistry, University of Delhi South Campus, New Delhi, Delhi, India
| | - Rajendra Kumar Saxena
- Department of Microbiology, University of Delhi South Campus, New Delhi, Delhi, India
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Kumar V, Jahan F, Kameswaran K, Mahajan RV, Saxena RK. Eco-friendly methodology for efficient synthesis and scale-up of 2-ethylhexyl-p-methoxycinnamate using Rhizopus oryzae lipase and its biological evaluation. J Ind Microbiol Biotechnol 2014; 41:907-12. [PMID: 24668019 DOI: 10.1007/s10295-014-1429-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 02/25/2014] [Indexed: 10/25/2022]
Abstract
Lipase-mediated synthesis of phenolic acid esters is a green and economical alternative to current chemical methods. Octyl methoxycinnamate, an important UVB-absorbing compound, was synthesized by the esterification of p-methoxycinnamic acid with 2-ethyl hexanol using Rhizopus oryzae lipase. A molar ratio of 1:2 of p-methoxycinnamic acid and 2-ethyl hexanol was found to give an optimum yield using cyclo-octane (50 ml) as reaction solvent, at a temperature of 45 °C, and 750 U of lipase, resulting in a yield of 91.3 % in 96 h. This reaction was successfully scaled up to 400-ml reaction size where 88.6 %bioconversion was achieved. The synthesized compound was found to have superior antioxidant activity as compared to ascorbic acid. The synthesized compound also exhibited good antimicrobial activity against Escherichia coli, Klebsiella pneumonia, Salmonella typhi, Staphylococcus aures, Candida albicans (yeast), Aspergillus niger, Alternaria solani, and Fussarium oxysporum by well diffusion method in terms of zone of inhibitions (in mm).
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Affiliation(s)
- Vinod Kumar
- Department of Microbiology, University of Delhi South Campus, New Delhi, 110021, India
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Raghuwanshi S, Misra S, Saxena RK. Treatment of wheat straw using tannase and white-rot fungus to improve feed utilization by ruminants. J Anim Sci Biotechnol 2014; 5:13. [PMID: 24555694 PMCID: PMC3974121 DOI: 10.1186/2049-1891-5-13] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Accepted: 02/16/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Current research to enrich cattle feed has primarily focused on treatment using white rot fungi, while there are scarce reports using the enzyme tannase, which is discussed only in reviews or in the form of a hypothesis. In this context, the aim of the present study was to evaluate the effect of tannase on wheat straw (WS) and also the effect of lyophilized tannase at concentrations of 0.1%, 0.2%, and 0.3% (w/w) on WS followed by fermentation with Ganoderma sp. for 10 d and compared in relation to biochemical parameters, crude protein (CP) content, and nutritional value by calculating the C/N ratio in order to improve the nutritional value of cattle feed. RESULTS Penicillium charlesii, a tannase-producing microorganism, produced 61.4 IU/mL of tannase in 54 h when 2% (w/v) tannic acid (TA) was initially used as a substrate in medium containing (% w/v) sucrose (1.0), NaNO3 (1.0), and MgSO4 (0.08 pH, 5.0) in a 300-L fermentor (working volume 220 L), and concomitantly fed with 1.0% (w/v) TA after 24 h. The yield of partially purified and lyophilized tannase was 5.8 IU/mg. The tannin-free myco-straw at 0.1% (w/w) tannase showed 37.8% (w/w) lignin degradation with only a 20.4% (w/w) decrease in cellulose content and the in vitro feed digestibility was 32.2%. An increase in CP content (up to 1.28-fold) along with a lower C/N ratio of 25.0%, as compared to myco-straw, was obtained. CONCLUSIONS The use of tannin-free myco-straw has potential to improve the nutritional content of cattle feed. This biological treatment process was safe, eco-friendly, easy to perform, and was less expensive as compared to other treatment methods.
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Affiliation(s)
| | | | - Rajendra Kumar Saxena
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110 021, India.
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Gupta N, Jassal M, Manchanda R, Saxena RK, Sharma B, Sharma S, Agrawal AK. Leaching of plastic polymers by plastic vials used for storing homoeopathic medicines: A preliminary study. Indian J Res Homoeopathy 2014. [DOI: 10.4103/0974-7168.135642] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Kumar V, Yadav S, Jahan F, Saxena RK. ORGANIC SYNTHESIS OF MAIZE STARCH-BASED POLYMER USINGRhizopus oryzaeLIPASE, SCALE UP, AND ITS CHARACTERIZATION. Prep Biochem Biotechnol 2013; 44:321-31. [DOI: 10.1080/10826068.2013.803481] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Yadav S, Rawat G, Tripathi P, Saxena RK. Dual substrate strategy to enhance butanol production using high cell inoculum and its efficient recovery by pervaporation. Bioresour Technol 2013; 152:377-383. [PMID: 24316481 DOI: 10.1016/j.biortech.2013.11.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [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: 09/23/2013] [Revised: 11/09/2013] [Accepted: 11/11/2013] [Indexed: 06/02/2023]
Abstract
The present study deals with the development of an efficient ABE fermentation process using mixed substrate strategy for butanol production wherein no acetone was produced. For this, glucose was supplemented in the medium containing glycerol as main substrate which leads to a higher butanol production of 17.75 g/L in 72 h by Clostridium acetobutylicum KF158795. Moreover, the high cell inoculum also resulted in an increased ABE productivity of 0.46 g/L/h. Further, industrial scalability of the process was also successfully validated in a 300 L fermenter. Furthermore, potential of the Polymeric (PolyRMem) and Zeolite (ZeoMem) membranes for separation of butanol from fermentation broth was also studied by testing the pervaporation performance through which the butanol was successfully recovered.
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Affiliation(s)
- Sweta Yadav
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India
| | - Garima Rawat
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India
| | - Priyanka Tripathi
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India
| | - R K Saxena
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India.
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Rawat G, Tripathi P, Yadav S, Saxena RK. An interactive study of influential parameters for shikimic acid production using statistical approach, scale up and its inhibitory action on different lipases. Bioresour Technol 2013; 144:675-679. [PMID: 23871288 DOI: 10.1016/j.biortech.2013.06.113] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [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: 04/19/2013] [Revised: 06/26/2013] [Accepted: 06/27/2013] [Indexed: 06/02/2023]
Abstract
Shikimic acid is the promising candidate as a building block for the industrial synthesis of drug Tamiflu used for the treatment of Swine flu. The fermentative production process using microbes present an excellent and even more sustainable alternative to the traditional plants based extraction methods. In the present study, the fermentative production of shikimic acid by Citrobacter freundii GR-21 (KC466031) was optimized by process engineering using a statistical modeling approach and a maximum amount of 16.78 g L(-1) was achieved. The process was also scaled up to 14L bioreactor to validate the production of shikimic acid. Further, the potential of anti-enzymatic nature of purified shikimic acid was evaluated for different lipases wherein, shikimic acid inhibited the hydrolysis of triglycerides by 55-60%. Shikimic acid also profoundly inhibited pancreatic lipase activity by 66%, thus providing another valuable therapeutic aspect for treating diet induced obesity in humans.
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Affiliation(s)
- Garima Rawat
- Department of Microbiology, University of Delhi South Campus, New Delhi, India.
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Rawat G, Kumar Saxena R. Production of shikimic acid: a potential candidate for developing drug formulation for Avian/Swine flu. Curr Opin Biotechnol 2013. [DOI: 10.1016/j.copbio.2013.05.051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Kumar V, Jahan F, Raghuwanshi S, Mahajan RV, Saxena RK. Immobilization of Rhizopus oryzae lipase on magnetic Fe3O4-chitosan beads and its potential in phenolic acids ester synthesis. BIOTECHNOL BIOPROC E 2013. [DOI: 10.1007/s12257-012-0793-8] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Jha A, Kumar A, Saxena RK, Kamalvanshi M, Chakravarty N. Effect of arbuscular mycorrhizal inoculations on seedling growth and biomass productivity of two bamboo species. Indian J Microbiol 2013; 52:281-5. [PMID: 23729895 DOI: 10.1007/s12088-011-0213-3] [Citation(s) in RCA: 4] [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] [Received: 02/09/2010] [Accepted: 04/25/2010] [Indexed: 10/17/2022] Open
Abstract
A study was conducted to identify suitable arbuscular mycorrhizal (AM) fungi for inoculation of Bambusa bambos and Dendrocalamus strictus at nursery stage for increasing growth and productivity. Twelve AM species, isolated from bamboo and other common trees of Bundelkhand were used for inoculations. In B. bambos, total dry weight and phosphorus (P) uptake were significantly increased by all studied fungi and shoot length was increased by eight AM inoculants. Maximum mycorrhizal dependency (MD) was recorded for Acaulospora scrobiculata (44.2%), followed by Glomus cerebriforme (41.6%) and G. intraradix (41.0%). In D. strictus, all tested AM inoculants significantly increased shoot length, dry shoot weight and P uptake, except Glomus 1. Dry root weight was significantly increased by only two inoculants namely, G. cerebriforme and G. etunicatum. Total dry weight was significantly increased by eight AM fungi. Maximum MD was recorded for G. cerebriforme (62.9%), followed by G. diaphanum (55.0%) and G. etunicatum (51.3%). Thus, the results showed that utilization of effective AM fungi can enhance the productivity of bamboo in the region.
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Affiliation(s)
- Anuradha Jha
- National Research Centre for Agroforestry, Near Pahuj Dam, Gwalior Road, Jhansi, UP 284 003 India
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Misra S, Raghuwanshi S, Saxena RK. Statistical approach to study the interactive effects of process parameters for enhanced xylitol production by Candida tropicalis and its potential for the synthesis of xylitol monoesters. FOOD SCI TECHNOL INT 2013; 19:535-48. [DOI: 10.1177/1082013212462230] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Previous results showed that an indigenously isolated yeast strain of Candida tropicalis was found to produce 12.11 g/L of xylitol under unoptimized conditions in presence of 50 g/L of xylose. In the present study, optimizing the process using one-variable at-a-time resulted in the production of 59.07 g/L of xylitol in 96 h in presence of 100 g/L xylose. Further optimization using response surface methodology led to the production of 65.45 g/L in medium containing 100 g/L xylose, 0.5% yeast extract, 0.03% MgSO4.7H2O and 0.2% KH2PO4, pH-4.5, 30 °C, 200 r/min for 96 h with 4% inoculum level. Addition of 1% methanol in response surface methodology optimized–medium led to the production of 67.12 g/L. Scaling up in 10 L fermentor resulted in productivity of 0.80 g/Lh with yield of 0.68 g/g. Efficient synthesis of xylitol esters was achieved with butyric acid (50.32%) and caproic acid (38.36%) in 4 h using Pseudomonas aeruginosa lipase in t-butanol: tetrahydrofuran (1:1 v/v).
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Affiliation(s)
- Swati Misra
- Department of Microbiology University of Delhi South Campus, New Delhi, India
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Rawat G, Tripathi P, Saxena RK. Expanding horizons of shikimic acid. Recent progresses in production and its endless frontiers in application and market trends. Appl Microbiol Biotechnol 2013; 97:4277-87. [PMID: 23553030 DOI: 10.1007/s00253-013-4840-y] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 03/05/2013] [Accepted: 03/06/2013] [Indexed: 10/27/2022]
Abstract
Shikimic acid is an industrially important chiral compound used as a key ingredient in formulation of drug Oseltamivir phosphate (Tamiflu) for the treatment of swine/avian flu. The high cost and limited availability of shikimic acid isolated from plants has detained the use of this valuable building block of the drug. It is a versatile compound having many characteristic properties for many synthetic reactions particularly in pharmaceuticals and cosmetic industries. By virtue of being a natural product, the relevant biochemical pathway in microorganisms can be harnessed into fermentation processes to produce shikimic acid. This is an excellent alternative for the sustainable and efficient production of shikimic acid over the tedious and cumbersome process of plant based extraction methods. Various strategies of shikimic acid production are reviewed and an account of comparison of their challenges, promises and restraint is presented. Furthermore, present review attempts to focus on the market trend of shikimic acid due to its high demand with particular emphasis laid on the pandemics of swine flu. This review not only covers the recent advances in shikimic acid production but also highlights the versatile applications and its market scenario. The concluding remarks and its potential as a commercial bulk chemical are discussed in the light of current research.
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Affiliation(s)
- Garima Rawat
- Department of Microbiology, University of Delhi South Campus, New Delhi 110021, India
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Tripathi P, Rawat G, Yadav S, Saxena RK. Fermentative production of shikimic acid: a paradigm shift of production concept from plant route to microbial route. Bioprocess Biosyst Eng 2013; 36:1665-73. [PMID: 23543261 DOI: 10.1007/s00449-013-0940-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2012] [Accepted: 03/04/2013] [Indexed: 11/30/2022]
Abstract
Different physiological and nutritional parameters affect the fermentative production of shikimic acid. In our study, Citrobacter freundii initially produced 0.62 g/L of shikimic acid in 72 h. However, when process optimization was employed, 5.11 g/L of shikimic acid was produced in the production medium consisting of glucose (5.0 %), asparagine (4.5 %), CaCO3 (2.0 %), at pH 6.0, when inoculated with 6 % inoculum and incubated at 30 ± 1 °C, 200 rpm for 60 h. Preliminary fed-batch studies have resulted in the production of 9.11 g/L of shikimic acid on feeding the production medium by 20 g/L of glucose at 24 h of the fermentation run. Production of similar amount of shikimic acid was observed when the optimized conditions were employed in a 10-L bioreactor as obtained in shake flask conditions. A total of 9.11 g/L of shikimic acid was produced in 60 h. This is approximately 14.69-fold increase in shikimic acid production when compared to the initial un-optimized production conditions. This has also resulted in the reduction of the production time. The present study provides useful information to the industrialists seeking environmentally benign technology for the production of bulk biomolecules through manipulation of various chemical parameters.
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Affiliation(s)
- Priyanka Tripathi
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India
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Saxena RK, Bhosale A, Kazi M, Shirahatti R, Panchwadker D, Diwaney S, Ladkat S. Microbial Flora on Aprons of Dental Healthcare Professionals. J Dent Allied Sci 2013. [DOI: 10.4103/2277-4696.159284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Mahajan RV, Saran S, Kameswaran K, Kumar V, Saxena RK. Efficient production of L-asparaginase from Bacillus licheniformis with low-glutaminase activity: optimization, scale up and acrylamide degradation studies. Bioresour Technol 2012; 125:11-6. [PMID: 23018158 DOI: 10.1016/j.biortech.2012.08.086] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2012] [Revised: 07/16/2012] [Accepted: 08/22/2012] [Indexed: 05/23/2023]
Abstract
L-Asparaginase has potential as an anti-cancer drug and for prevention of acrylamide formation in fried and baked foods. Production of the enzyme by Bacillus licheniformis (RAM-8) was optimized by process engineering using a statistical modeling approach and a maximum yield of 32.26 IU/ml was achieved. The L-asparaginase exhibited glutaminase activity of only 0.8 IU/ml and would therefore be less prone to cause the side effects associated with asparaginase therapy compared to enzyme preparations with higher glutaminase activities. When production was carried out in a 30-L bioreactor, enzyme production reached 29.94 IU/ml in 15 h. The enzyme inhibited poly-acrylamide formation in 10% acrylamide solution and reduced acrylamide formation in fried potatoes by 80%.
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Affiliation(s)
- Richi V Mahajan
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110021, India
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Kumar N, Varshney S, Saxena RK, Kumar R, Bisht SS. Retained foreign body in sino-orbital region. Indian J Otolaryngol Head Neck Surg 2012; 58:194-5. [PMID: 23120285 DOI: 10.1007/bf03050788] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
It is rare to find foreign bodies in nose and paranasal sinuses. The further rarity is to encounter impacted foreign body in this region and route of entry being through the orbit. We are here by presenting a case, where a metallic foreign body was retained for duration of 4 months in sino - orbital region.
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Affiliation(s)
- Navneet Kumar
- Department of E.N.T., Himalayan Institute of Medical Sciences, Swami Ram Nagar, Doiwala, 248140 Dehradun (Uttaranchal)
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Abstract
A 9 years old boy reported with left nasal blockage, occasional left nasal bleeding, protruding left eye ball and widening of the nasal bridge for the last nine months. Clinical examination and radiological evaluation were suggeitive of fibrous dysplasia. Mass was excised by transfacial and transcranial approach. Histopathology of the excised muns proved to be a case of haemorrhagic cystic sino-nasal fibrous dysplasia.
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Affiliation(s)
- R K Saxena
- Himalayan Institute of Medical Sciences, 248 140 Jollygrant, Dehradun (U.P.)
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Anand P, Saxena RK. A comparative study of solvent-assisted pretreatment of biodiesel derived crude glycerol on growth and 1,3-propanediol production from Citrobacter freundii. N Biotechnol 2012; 29:199-205. [DOI: 10.1016/j.nbt.2011.05.010] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2011] [Revised: 05/18/2011] [Accepted: 05/24/2011] [Indexed: 11/15/2022]
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Misra S, Raghuwanshi S, Gupta P, Dutt K, Saxena RK. Fermentation behavior of osmophilic yeast Candida tropicalis isolated from the nectar of Hibiscus rosa sinensis flowers for xylitol production. Antonie Van Leeuwenhoek 2011; 101:393-402. [PMID: 21956659 DOI: 10.1007/s10482-011-9646-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2011] [Accepted: 09/16/2011] [Indexed: 10/17/2022]
Abstract
Eighteen yeast species belonging to seven genera were isolated from ten samples of nectar from Hibiscus rosa sinensis and investigated for xylitol production using D-xylose as sole carbon source. Amongst these isolates, no. 10 was selected as the best xylitol producer and identified as Candida tropicalis on the basis of morphological, biochemical and 26S rDNA sequencing. C. tropicalis produced 12.11 gl(-1) of xylitol in presence of 50 gl(-1) of xylose in 72 h at pH 5, 30°C and 200 rpm. The strain of C. tropicalis obtained through xylose enrichment technique has resulted in a yield of 0.5 gg(-1) with a xylitol volumetric productivity of 1.07 gl(-1)h(-1) in the presence of 300 gl(-1) of xylose through batch fermentation. This organism has been reported for the first time from Hibiscus rosa sinensis flowers. Realizing, the importance of this high valued compound, as a sugar substitute, xylose enrichment technique was developed in order to utilize even higher concentrations of xylose as substrate for maximum xylitol production.
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Affiliation(s)
- Swati Misra
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110 021, India
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Raghuwanshi S, Dutt K, Gupta P, Misra S, Saxena RK. Bacillus sphaericus: The highest bacterial tannase producer with potential for gallic acid synthesis. J Biosci Bioeng 2011; 111:635-40. [DOI: 10.1016/j.jbiosc.2011.02.008] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2010] [Revised: 02/11/2011] [Accepted: 02/16/2011] [Indexed: 11/30/2022]
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Anand P, Saxena RK, Marwah RG. A novel downstream process for 1,3-propanediol from glycerol-based fermentation. Appl Microbiol Biotechnol 2011; 90:1267-76. [DOI: 10.1007/s00253-011-3161-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2010] [Revised: 01/27/2011] [Accepted: 01/29/2011] [Indexed: 11/30/2022]
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Lalitha PV, Biswas S, Pillai CR, Seth RK, Saxena RK. Expression, purification and characterization of allelic variants of MSP-1(42) from Indian Plasmodium falciparum isolates. Vaccine 2010; 28:4661-7. [PMID: 20452429 DOI: 10.1016/j.vaccine.2010.04.068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2009] [Revised: 04/10/2010] [Accepted: 04/23/2010] [Indexed: 10/19/2022]
Abstract
The C-terminal 19 and 42 kDa fragments of Plasmodium falciparum merozoite surface protein 1 (MSP-1) have shown to be protective in animals against lethal parasite challenge. The MSP-1(19) being highly conserved may lack sufficient number of T-cell epitopes in order to elicit a broader response in genetically diverse populations. The inclusion of additional epitopes from the N-terminal MSP-1(42) has shown to enhance the protective efficacy of MSP-1(19) vaccine. In an attempt to examine the strain specific immunogenicity to MSP-1, we have cloned and expressed three diverse allelic variants of MSP-1(42) from Indian P. falciparum isolates in bacteria. Among three alleles, one was extremely rare and not been found before. These purified and refolded recombinant products were recognized by conformation specific monoclonal antibodies and hyper-immune sera. Immunization of mice and rabbits with the purified proteins generated high titer biologically active polyclonal antibodies supporting further development of this vaccine candidate antigen.
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Affiliation(s)
- P V Lalitha
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
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Singh GP, Saxena RK, Priyadarshy V. Amphotericin B--fat emulsion in treatment of visceral leishmaniasis--a cost effective substitute for liposomal amphotericin B. J Indian Med Assoc 2010; 108:27-28. [PMID: 20839576] [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: 05/29/2023]
Abstract
In spite of high dosage and prolonged treatment schedule of sodium antimony gluconate, unresponsiveness and relapse ranging from 25 to 40% has been reported. The cure rate of 90 to 92.9% with amphotericin B-fat emulsion is comparable to that with liposomal amphotericin B (80 to 100%). Due to high cost liposomal amphotericin B is beyond the reach of most of the Indian patients, whereas the cost of treatment with amphotericin B-fat emulsion is quite affordable. Further large scale studies with amphotericin B-fat emulsion are required to evaluate its effectiveness in Indian kala-azar patients and to establish its optimal dose.
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Affiliation(s)
- Ganesh Pd Singh
- Department of Medicine, Patna Medical College and Hospital, Patna
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Gupta P, Dutt K, Misra S, Raghuwanshi S, Saxena RK. Characterization of cross-linked immobilized lipase from thermophilic mould Thermomyces lanuginosa using glutaraldehyde. Bioresour Technol 2009; 100:4074-4076. [PMID: 19403306 DOI: 10.1016/j.biortech.2009.03.076] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Revised: 03/26/2009] [Accepted: 03/26/2009] [Indexed: 05/27/2023]
Abstract
Cross-linked enzyme aggregates (CLEAs) have emerged as an interesting biocatalyst design for immobilization. Using this approach, a 1,3 regiospecific, alkaline and thermostable lipase from Thermomyces lanuginosa was immobilized. Efficient cross-linking was observed when ammonium sulphate was used as precipitant along with a two fold increase in activity in presence of SDS. The TEM and SEM microphotographs of the CLEAs formed reveal that the enzyme aggregates are larger in size as compared to the free lipase due to the cross-linking of enzyme aggregates with glutaraldehyde. The stability and reusability of the CLEA with respect to olive oil hydrolysis was evaluated. The CLEA showed more than 90% residual activity even after 10 cycles of repeated use.
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Affiliation(s)
- Pritesh Gupta
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110 021, India
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Dutt K, Gupta P, Saran S, Misra S, Saxena RK. Production of milk-clotting protease from Bacillus subtilis. Appl Biochem Biotechnol 2009; 158:761-72. [PMID: 19172237 DOI: 10.1007/s12010-008-8504-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2008] [Accepted: 12/17/2008] [Indexed: 10/21/2022]
Abstract
An indigenous Bacillus subtilis strain isolated from soil was found to be a potent milk-clotting protease (mcp) producer. Production optimized using response surface methodology (RSM) yielded 1,190 U/ml of enzyme in medium containing 6% fructose, 1% casein, 0.3% NH4NO3, 10 mM CaCl2, pH 6.0 and inoculated with 3% inoculum and incubated at 250 rpm for 72 h. Solid-state fermentation resulted in 1,080 and 952.3 U/gds of milk-clotting protease using soybean meal and rice bran, respectively, with higher proteolytic values of 18.97 and 9.1 IU/gds. Production in a biphasic system using an overlay of RSM-optimized medium on solid layer of 6% fructose and 1% casein with 1.5% agar resulted in significant enzyme production. Maximum mcp was obtained using a biphasic system where solid: liquid ratio of 3.0 resulted in a final yield of 1,276.65 U/ml with a yield index of 1.80 as compared to static liquid culture. However, significant increase or difference was noted as compared to yield obtained after RSM. This is the first report on the use of RSM for production of mcp from a bacterial species.
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Affiliation(s)
- Kakoli Dutt
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110021, India
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Lalitha PV, Biswas S, Pillai CR, Saxena RK. Immunogenicity of a recombinant malaria vaccine candidate, domain I+II of AMA-1 ectodomain, from Indian P. falciparum alleles. Vaccine 2008; 26:4526-35. [PMID: 18590786 DOI: 10.1016/j.vaccine.2008.06.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2008] [Revised: 05/21/2008] [Accepted: 06/11/2008] [Indexed: 11/28/2022]
Abstract
Among the few vaccine candidates under development, apical membrane antigen (AMA-1) of Plasmodium falciparum is one of the most promising erythrocyte stage malaria vaccine candidates under consideration. The overall structure of AMA-1 appears to be conserved as compared to other surface proteins, but there are numerous amino acid substitutions identified among different P. falciparum isolates. Antisera raised against recombinant AMA-1 or naturally acquired human antibodies were strongly inhibitory only towards homologous parasites. In an attempt to examine the strain specificity of antibodies elicited to AMA-1, we have cloned, expressed and purified two allelic variants of domain I+II of AMA-1 ectodomain from Indian P. falciparum isolates in bacteria. One of these is a new haplotype not reported so far and varies in 18 aa positions from the geographically diverse forms 3D7 and 15 from FVO. Refolded proteins were recognized by a conformation specific monoclonal antibody 4G2.dc1 and hyper immune sera. Immunization of mice and rabbits with the purified proteins using CFA/IFA adjuvant generated high titer polyclonal antibodies. Both the alleles induced high levels of IgG1, IgG2a and IgG2b and a low level of IgG3 in mice. Lymphocyte proliferation assays using splenocytes from immunized mice showed significant proliferative responses and cytokines interleukin-2 (IL-2), IL-4, IL-10 and IFN-gamma presence in the culture supernatants. The anti-AMA-1 rabbit antibodies obtained with both the proteins were active in an in vitro parasite growth invasion/inhibition assay. These results suggest that recombinant AMA-1 domain I+II formulated with CFA/IFA adjuvant elicited cellular and humoral responses and is capable of inducing high titer invasion inhibitory antibodies supporting further development of this vaccine candidate.
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Affiliation(s)
- P V Lalitha
- School of Life Sciences, Jawaharlal Nehru University, New Delhi 110067, India.
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Sharma S, Agarwal L, Saxena RK. Purification, immobilization and characterization of tannase from Penicillium variable. Bioresour Technol 2008; 99:2544-51. [PMID: 17570660 DOI: 10.1016/j.biortech.2007.04.035] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2006] [Revised: 04/22/2007] [Accepted: 04/22/2007] [Indexed: 05/15/2023]
Abstract
Tannase from Penicillium variable IARI 2031 was purified by a two-step purification strategy comprising of ultra-filtration using 100 kDa molecular weight cutoff and gel-filtration using Sephadex G-200. A purification fold of 135 with 91% yield of tannase was obtained. The enzyme has temperature and pH optima of 50 degrees C and 5 degrees C, respectively. However, the functional temperature range is from 25 to 80 degrees C and functional pH range is from 3.0 to 8.0. This tannase could successfully be immobilized on Amberlite IR where it retains about 85% of the initial catalytic activity even after ninth cycle of its use. Based on the Michaelis-Menten constant (Km) of tannase, tannic acid is the best substrate with Km of 32 mM and Vmax of 1.11 micromol ml(-1)min(-1). Tannase is inhibited by phenyl methyl sulphonyl fluoride (PMSF) and N-ethylmaleimide retaining only 28.1% and 19% residual activity indicating that this enzyme belongs to the class of serine hydrolases. Tannase in both crude and crude lyophilized forms is stable for one year retaining more than 60% residual activity.
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Affiliation(s)
- Shashi Sharma
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110 021, India
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Gajre SS, Singh U, Saxena RK, Anand S. Electrical impedance signal analysis in assessing the possibility of non-invasive diagnosis of knee osteoarthritis. J Med Eng Technol 2007; 31:288-99. [PMID: 17566932 DOI: 10.1080/03091900600863745] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [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: 01/11/2023]
Abstract
Knee osteoarthritis (OA) is a degenerating disorder that leads to pain, disability and dependence. Although significant numbers of elderly people are affected by this irreversible damage, not many non-invasive methods have been found that can detect onset of OA. The traditional x-ray has the disadvantage of detecting a problem only after many changes have taken place. Others, such as MRI and ultrasound, are either expensive or unsuitable for mass screening and repeated use. In this paper, an attempt has been made to study the usefulness of electrical impedance plethysmography (EIP) in non-invasive diagnosis of knee OA. In two experiments on 10 OA knees and eight control knees in groups aged 45 - 65 years (OA group: 62.40 +/- 3.47 years, controls: 53.38 +/- 8.55 years), knee swing (active flexion and extension of leg in sitting position, KS) and normal walking (WN) electrical impedance changes (DeltaZ) around the knee were analysed. The results indicate that there is significant difference in amplitudes of signals. Difference in mean of variances of two groups was significant (p < 0.05) for KS and WN. The difference in the mean rms values was also significant (p < 0.05) for KS and WN. Impedance changes suggest that EIP signal around the knee have the potential for non-invasive diagnosis of knee OA.
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Affiliation(s)
- S S Gajre
- Centre for Biomedical Engineering, Indian Institute of Technology, Hauz Khas, New Delhi, India.
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Sharma S, Agarwal L, Saxena RK. Statistical optimization for tannase production from Aspergillus niger under submerged fermentation. Indian J Microbiol 2007; 47:132-8. [PMID: 23100655 DOI: 10.1007/s12088-007-0026-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2006] [Revised: 02/23/2007] [Accepted: 05/07/2007] [Indexed: 11/29/2022] Open
Abstract
Statistically based experimental design was employed for the optimization of fermentation conditions for maximum production of enzyme tannase from Aspergillus niger. Central composite rotatable design (CCRD) falling under response surface methodology (RSM) was used. Based on the results of 'one-at-a-time' approach in submerged fermentation, the most influencing factors for tannase production from A. niger were concentrations of tannic acid and sodium nitrate, agitation rate and incubation period. Hence, to achieve the maximum yield of tannase, interaction of these factors was studied at optimum production pH of 5.0 by RSM. The optimum values of parameters obtained through RSM were 5% tannic acid, 0.8% sodium nitrate, 5.0 pH, 5 × 10(7) spores/50mL inoculum density, 150 rpm agitation and incubation period of 48 h which resulted in production of 19.7 UmL(-1) of the enzyme. This activity was almost double as compared to the amount obtained by 'one-at-a-time' approach (9.8 UmL(-1)).
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Affiliation(s)
- S Sharma
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110 021 India
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Saran S, Isar J, Saxena RK. A modified method for the detection of microbial proteases on agar plates using tannic acid. ACTA ACUST UNITED AC 2007; 70:697-9. [PMID: 17434593 DOI: 10.1016/j.jbbm.2007.03.005] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Revised: 03/02/2007] [Accepted: 03/12/2007] [Indexed: 12/18/2022]
Abstract
In routine assay for the screening of microbes producing proteases, 10% trichloroaceticacid (TCA) is flooded on the milk agar plates after inoculation and required incubation to precipitate the protein. However, the clarity of the hydrolyzed zone is not very sharp and distinct. We herein present an improved assay for detecting the presence of extracellular protease from microorganisms on agar plates. In this method 10% tannic acid is flooded on the milk agar plate (in place of, TCA) to observe the zone of hydrolysis. Tannic acid sharply increases the colour intensity of the plate, as it favours the precipitation of the unhydrolyzed protein in the plate, thereby improving the contrast between the intact zones and the enzymatic lyses zones of the substrate. Our results indicate that this method is useful to detect extracellular proteases produced by both fungi as well as bacteria. The method used in the present study is sensitive, and can be easily performed for screening of large number of microbial cultures. This is the first report on the use of tannic acid for the detection of microbial proteases.
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Affiliation(s)
- Saurabh Saran
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi-110021, India
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Isar J, Agarwal L, Saran S, Kaushik R, Saxena RK. A statistical approach to study the interactive effects of process parameters on succinic acid production from Bacteroides fragilis. Anaerobe 2007; 13:50-6. [PMID: 17303449 DOI: 10.1016/j.anaerobe.2006.12.002] [Citation(s) in RCA: 16] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2006] [Revised: 11/21/2006] [Accepted: 12/12/2006] [Indexed: 11/24/2022]
Abstract
A statistical approach response surface methodology (RSM) was used to study the production of succinic acid from Bacteroides fragilis. The most influential parameters for succinic acid production obtained through one-at-a-time method were glucose, tryptone, sodium carbonate, inoculum size and incubation period. These resulted in the production of 5.4gL(-1) of succinic acid in 48h from B. fragilis under anaerobic conditions. Based on these results, a statistical method, face-centered central composite design (FCCCD) falling under RSM was employed for further enhancing the succinic acid production and to monitor the interactive effect of these parameters, which resulted in a more than 2-fold increase in yield (12.5gL(-1) in 24h). The analysis of variance (ANOVA) showed the adequacy of the model and the verification experiments confirmed its validity. On subsequent scale-up in a 10-L bioreactor using conditions optimized through RSM, 20.0gL(-1) of succinic acid was obtained in 24h. This clearly indicated that the model stood valid even on large scale. Thus, the statistical optimization strategy led to an approximately 4-fold increase in the yield of succinic acid. This is the first report on the use of FCCCD to improve succinic acid production from B. fragilis. The present study provides useful information about the regulation of succinic acid synthesis through manipulation of various physiochemical parameters.
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Affiliation(s)
- Jasmine Isar
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110021, India
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Agarwal L, Isar J, Meghwanshi GK, Saxena RK. Influence of environmental and nutritional factors on succinic acid production and enzymes of reverse tricarboxylic acid cycle from Enterococcus flavescens. Enzyme Microb Technol 2007. [DOI: 10.1016/j.enzmictec.2006.05.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Sharma G, Saxena RK, Mishra P. Differential effects of cyclic and static pressure on biochemical and morphological properties of chondrocytes from articular cartilage. Clin Biomech (Bristol, Avon) 2007; 22:248-55. [PMID: 17110007 DOI: 10.1016/j.clinbiomech.2006.09.008] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2006] [Revised: 09/22/2006] [Accepted: 09/26/2006] [Indexed: 02/07/2023]
Abstract
BACKGROUND Mechanical stresses are known to play important role on articular cartilage functions in vivo and also on cartilage explants and chondrocytes monolayer culture. This study examined the differential effect of cyclic and static pressures on chondrocytes cultured in alginate matrix, which is physiologically closer to the in vivo environment of cells in cartilage. METHODS Goat knee joint articular cartilage chondrocytes cultured in alginate beads were exposed to 1.2 and 2.4 MPa cyclic and static loadings via a custom-made cam/follower based machine. Biochemical contents (glycosaminoglycan, collagen, DNA) and protease activity of cells were analyzed separately in cellular matrix, further removed matrix and in culture medium. Morphology of chondrocytes was studied under transmission electron microscopy. FINDINGS Compared with controls (unloaded cells), cyclic loading increased the glycosaminoglycan content of cells at 1.2 and 2.4 MPa in cellular matrix and further removed matrix (P<0.001) whereas it decreased at similar static loads (P<0.001). In alginate matrix, chondrocytes released a metalloprotease, which required Mn(2+) for activity. Both cyclic load levels inhibited its specific activity in cellular matrix but increased it at static loading (P<0.001). The protease specific activity in further removed matrix increased at both cyclic and static loadings (P<0.001). Transmission electron microscopy data showed improved cells ultrastructure and cell-matrix interactions under cyclic load whereas these deteriorated under static loadings. INTERPRETATION The study suggests that cyclic load has a positive effect on chondrocytes metabolism and morphology whereas static load has a degenerative effect.
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Affiliation(s)
- Garima Sharma
- Centre for Biomedical Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110 016, India
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Singh GR, Aithal HP, Saxena RK, Kinjavdekar P, Hoque M, Maiti SK, Pawde AM, Joshi HC. In Vitro Biomechanical Properties of Linear, Circular, and Hybrid External Skeletal Fixation Devices for Use in Large Ruminants. Vet Surg 2007; 36:80-7. [PMID: 17214825 DOI: 10.1111/j.1532-950x.2007.00239.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [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: 11/30/2022]
Abstract
OBJECTIVE To report the biomechanical properties of 3 external skeletal fixation (ESF) devices for use in large ruminants. STUDY DESIGN In vitro biomechanical testing of ESF constructs. SAMPLE POPULATION Adult buffalo (weighing, 250-350 kg) tibiae (n=27). METHODS ESF constructs (bilateral linear fixator [BLF], 4-ring circular external fixator [CEF], and hybrid fixator [HF]) were made using mild (low carbon) steel implants plated with nickel and cadaveric buffalo tibiae. After ESF application, a 1 cm mid-diaphyseal gap was created. Constructs were loaded to failure, on a materials testing machine, in axial compression (n=5/ESF type) and craniocaudal bending (n=3/ESF type). In addition, 3 CEF constructs were tested in intact tibiae under craniocaudal bending. RESULT In compression, HF was the strongest and most rigid construct; yield load was significantly higher for HF than for BLF or CEF. Under bending, both CEF and HF had similar strength and modulus of elasticity. Strength for BLF was higher than CEF and HF, whereas the reverse was true for modulus of elasticity. CONCLUSIONS ESF made from mild steel for use in large ruminants could withstand<or=300 kg load applied under compression and bending moment without any substantial adverse biomechanical effects on the constructs. HF was most rigid and strong under compression, whereas BLF was strongest in craniocaudal bending. Overall, HF seemed biomechanically the most suitable ESF device. CLINICAL RELEVANCE A hybrid ESF developed using mild steel is sufficiently strong and economical and may prove useful for fixation of long bone fractures in large ruminants (weighing<or=300 kg).
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Affiliation(s)
- Gaj Raj Singh
- Division of Surgery, Indian Veterinary Research Institute, Izatnagar, Uttar Pradesh, India
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Saxena RK, Dutt K, Agarwal L, Nayyar P. A highly thermostable and alkaline amylase from a Bacillus sp. PN5. Bioresour Technol 2007; 98:260-5. [PMID: 16524725 DOI: 10.1016/j.biortech.2006.01.016] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2005] [Revised: 01/07/2006] [Accepted: 01/18/2006] [Indexed: 05/07/2023]
Abstract
A highly thermostable alkaline amylase producing Bacillus sp. PN5 was isolated from soil, which yielded 65.23 U mL(-1) of amylase in medium containing (%) 0.6 starch, 0.5 peptone and 0.3 yeast extract at 60 degrees C, pH 7.0 after 60 h of incubation. Maximum amylase activity was at pH 10.0 and 90 degrees C. The enzyme retained 80% activity after 1 h at pH 10.0. It exhibited 65% activity at 105 degrees C and had 100% stability in the temperature range between 80 and 100 degrees C for 1 h. In addition, there was 86.36% stability after 1-h incubation with sodium dodecylsulphate. These properties indicated possible use of this amylase in starch saccharification and detergent formulation.
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Affiliation(s)
- Rajendra Kumar Saxena
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110021, India.
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Agarwal L, Isar J, Meghwanshi GK, Saxena RK. A cost effective fermentative production of succinic acid from cane molasses and corn steep liquor by Escherichia coli. J Appl Microbiol 2006; 100:1348-54. [PMID: 16696683 DOI: 10.1111/j.1365-2672.2006.02894.x] [Citation(s) in RCA: 31] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
AIM Development and optimization of an efficient and inexpensive medium for succinic acid production by Escherichia coli under anaerobic conditions. METHODS AND RESULTS Initially, 0.8 gl(-1) of succinic acid was produced in 60 h in 300-ml medium. On optimization, glucose and peptone were replaced by cane molasses and corn steep liquor. Three hundred ml of this medium was inoculated with 4% (v/v) of seed inoculum, incubated at 39 degrees C for 72 h, resulted in 7.1 gl(-1) of succinic acid in 36 h. Scale up in a 10-l fermentor under conditions of controlled pH and continuous CO2 supply in this medium resulted in 17 gl(-1) of succinic acid in 30 h. CONCLUSIONS A ninefold increase in succinic acid production was obtained in 500-ml anaerobic bottles with optimized medium having cane molasses and corn steep liquor as against initial medium containing glucose and peptone. However, a subsequent scale up in a 10-l fermentor resulted in a 2.5-fold increase in succinic acid production as against optimized medium used in 500-ml anaerobic bottles. SIGNIFICANCE AND IMPACT OF THE STUDY Succinic acid production was enhanced in medium consisting of inexpensive carbon and nitrogen sources in a shorter span of time.
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Affiliation(s)
- L Agarwal
- Department of Microbiology, University of Delhi, New Delhi, India
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Isar J, Agarwal L, Saran S, Saxena RK. Succinic acid production from Bacteroides fragilis: process optimization and scale up in a bioreactor. Anaerobe 2006; 12:231-7. [PMID: 16978889 DOI: 10.1016/j.anaerobe.2006.07.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2006] [Revised: 04/15/2006] [Accepted: 07/11/2006] [Indexed: 10/24/2022]
Abstract
We report the effect of different physiological and nutritional parameters on succinic acid production from Bacteroides fragilis. This strain initially produced 0.70gL(-1) of succinic acid in 60h. However, when process optimization was employed, 5.4gL(-1) of succinic acid was produced in medium consisting of glucose (1.5%); tryptone (2.5%); Na(2)CO(3) (1.5%), at pH 7.0, when inoculated with 4% inoculum and incubated at 37 degrees C, 100rpm for 48h. A marked enhancement in succinic acid production was observed when the optimized conditions were employed in a 10L bioreactor. A total of 12.5gL(-1) of succinic acid was produced in 30h. This is approximately 12-fold increase in succinic acid production when compared to the initial un-optimized medium production. This enhancement in succinic acid production may be due to the control of CO(2) supply and the impeller speed. This is also resulted in the reduction of the production time. The present study provides useful information to the industrialists seeking environmentally benign technology for the production of bulk biomolecules through manipulation of various chemical parameters.
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Affiliation(s)
- Jasmine Isar
- Department of Microbiology, University of Delhi South Campus, Benito Juarez Road, New Delhi 110021, India
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Isar J, Agarwal L, Saran S, Gupta P, Saxena RK. Effect of process parameters on succinic acid production in Escherichia coli W3110 and enzymes involved in the reductive tricarboxylic acid cycle. Can J Microbiol 2006; 52:893-902. [PMID: 17110982 DOI: 10.1139/w06-034] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [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: 11/22/2022]
Abstract
The effect of process optimization on succinic acid production by Escherichia coli W3110 and on enzymes involved in the reverse tricarboxylic acid cycle was studied. Approximately, 7.02 g L–1 of succinic acid was produced in 60 h at pH 7.0 in 500 mL anaerobic bottles containing 300 mL of the medium, wherein the sucrose concentration was 2.5%, the ratio of tryptone to ammonium hydrogen phosphate was 1:1, and the concentration of magnesium carbon ate was 1.5%. When these optimized fermentation conditions were employed in a 10 L bioreactor, 11.2 g L–1 of succinic acid was produced in 48 h. This is a 10-fold increase in succinic acid production from the initial titer of 0.94 g L–1. This clearly indicates the importance of process optimization, where by manipulating the media composition and production conditions, a remarkable increase in the production of the desired biomolecule can be obtained. The production of succinic acid is a multi-step reaction through the reverse tricarboxylic acid cycle. A linear relationship was observed between succinic acid production and the enzyme activities. The enzyme activities were found to increase in the order phospho-enol-pyruvate carboxylase < malate dehydrogenase < fumarase < fumarate reductase. The activity of phospho-enol-pyruvate carboxykinase was also estimated. Results indicate that this enzyme was not a very active participant in the production of succinic acid, since it catalyzes the phosphorylation of oxaloacetic acid to yield phospho-enol-pyruvate.Key words: anaerobic production, succinic acid, Escherichia coli, process optimization, reverse tricarboxylic acid cycle enzymes, fermentation.
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Affiliation(s)
- Jasmine Isar
- Department of Microbiology, University of Delhi South Campus, New Delhi, India
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Isar J, Agarwal L, Saran S, Saxena RK. A statistical method for enhancing the production of succinic acid from Escherichia coli under anaerobic conditions. Bioresour Technol 2006; 97:1443-8. [PMID: 16162408 DOI: 10.1016/j.biortech.2005.07.014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2005] [Revised: 07/19/2005] [Accepted: 07/21/2005] [Indexed: 05/04/2023]
Abstract
The most influential parameters for succinic acid production obtained through one at a time method were sucrose, tryptone, magnesium carbonate, inoculum size and incubation period. These resulted in the production of 7.0 g L(-1) of succinic acid in 60 h from Escherichia coli W3110 under anaerobic conditions. Based on these results, a statistical method, face centered central composite design (FCCCD) falling under response surface method (RSM) was employed for further enhancing the succinic acid production and to monitor the interactive effect of these parameters, which resulted in a twofold increase in yield (14.3 g L(-1) in 48 h). The analysis of variance (ANOVA) showed the adequacy of the model and the verification experiments confirmed its validity. On subsequent scale-up in a 10-L bioreactor using conditions optimized through RSM, 24.2 g L(-1) of succinic acid was obtained in 30 h. This clearly indicated that the model stood valid even on large-scale. Thus, the statistical optimization strategy led to a 3.5-fold increase in the yield of succinic acid. This is the first report on the use of FCCCD to improve succinic acid production from E. coli.
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Affiliation(s)
- Jasmine Isar
- Department of Microbiology, University of Delhi South Campus, New Delhi, India
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Abstract
Arterio-venous malformations (AVM) are rare in head and neck region and are generally arise from intracranial vessels. We present a case of spontaneous AV malformation in the post auricular region with posterior auricular artery as the feeding vessel that was diagnosed by Color Doppler sonography.
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Affiliation(s)
- Rajesh
- Department of ENT & Head neck surgery, Himalayan Institute of Medical Sciences, Jollygrant, Dehradun, Uttranchal, India
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Abstract
Esthesioneuroblastoma (ENB) is an extremely rare malignant neoplasm of the nasal cavity. We report the case of a middle aged man who presented with a 6-months history of progressive nasal obstruction, watering of the eye, headache and occasional epistaxis. A diagnosis of esthesioneuroblastoma was established by histopathology and confirmed by immunohistochemistry. On staging the mass was classified as a kadish stage C tumor. The mass was excised via a craniofacial resection through a bi-coronal approach and the tumor mass was peeled away completely from the frontal lobe dura. The patient underwent postoperative radiation, and he was free of recurrence at follow-up 3 months later.
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Affiliation(s)
- S S Bist
- Department of E.N.T & Neurosurgery, Himalayan Institute of Medical Science, Dehradun (U.A)
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Anand P, Isar J, Saran S, Saxena RK. Bioaccumulation of copper by Trichoderma viride. Bioresour Technol 2006; 97:1018-25. [PMID: 16324839 DOI: 10.1016/j.biortech.2005.04.046] [Citation(s) in RCA: 51] [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: 01/05/2005] [Revised: 04/26/2005] [Accepted: 04/29/2005] [Indexed: 05/05/2023]
Abstract
Studies were carried out on interaction of Trichoderma viride with copper and reports bioaccumulation as a mechanism of copper tolerance during growth. There was a marked increase in the lag phase of the growth, which was concentration dependent. At a concentration of 100 mg/L of CuCl2.2H2O, 81% of Cu(II) were removed by 3.4 g/L of the biomass in 72 h. The process was temperature and pH dependent. The maximum copper bioaccumulation occurred at 30 degrees C, pH 5.0. Metabolic inhibitors such as sodium azide (NaN3) and 2,4-dinitrophenol (2,4-DNP) drastically reduced the extent of Cu(II) bioaccumulation. Electron microscopy and cell fractionation studies revealed that 70-80% of copper was present as a layer on the cell wall surface.
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Affiliation(s)
- Purnima Anand
- Department of Microbiology, University of Delhi, South Campus, Benito Juarez Road, New Delhi 110 021, India
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Affiliation(s)
- Pratima Gupta
- Department of Microbiology, Himalayan Institute of Medical Sciences, Jollygrant, Dehradun (UA) 248140, India
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