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Yu Q, Sun C, Cao W, Liu R, Abd-Alla MH, Rasmey AHM. Rumen fluid pretreatment promotes anaerobic methane production: revealing microbial dynamics driving increased acid yield from different concentrations of corn straw. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024:10.1007/s11356-024-33615-0. [PMID: 38733442 DOI: 10.1007/s11356-024-33615-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 05/05/2024] [Indexed: 05/13/2024]
Abstract
In this work, the corn straw (CS) with concentrations of 3%, 6%, and 9% (w/v) were pretreated by rumen fluid (RF) and then used for batched mesophilic biogas production. The results showed that after a 6-day pretreatment, volatile fatty acid (VFAs) production of 3.78, 8.27, and 10.4 g/L could be found in 3%, 6%, and 9%, respectively. When concerning with biogas production, the highest accumulative methane production of 149.1 mL CH4/g volatile solid was achieved by 6% pretreated CS, which was 22% and 45% higher than 3% and 9%, respectively. Also, it was 3.6 times higher than the same concentration of unpretreated CS. The results of the microbial community structure analysis revealed that the 6% CS pretreatment not only maintained a microbial community with the highest richness and diversity, but also exhibited the highest relative abundance of Firmicutes (45%) and Euryarchaeota (3.9%). This high abundance was conducive to its elevated production of VFAs and methane. These findings provide scientific reference for the utilization of CS and support the development of agricultural waste resource utilization and environmental protection.
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Affiliation(s)
- Qing Yu
- School of Chemistry and Chemical Engineering, Zhejiang Sci-Tech University, Hangzhou, 310018, People's Republic of China
- College of Biological, Chemical Science and Engineering, Jiaxing University, Jiaxing, 314001, People's Republic of China
| | - Chen Sun
- College of Biological, Chemical Science and Engineering, Jiaxing University, Jiaxing, 314001, People's Republic of China.
| | - Weixing Cao
- College of Biological, Chemical Science and Engineering, Jiaxing University, Jiaxing, 314001, People's Republic of China
| | - Ronghou Liu
- Biomass Energy Engineering Research Centre, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai, 200240, People's Republic of China
| | - Mohamed Hemida Abd-Alla
- Botany and Microbiology Department, Faculty of Science, Assiut University, Assiut, 71516, Egypt
| | - Abdel-Hamied M Rasmey
- Botany and Microbiology Department, Faculty of Science, Suez University, Suez, 43518, Egypt
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Liang J, Zhang R, Chang J, Chen L, Nabi M, Zhang H, Zhang G, Zhang P. Rumen microbes, enzymes, metabolisms, and application in lignocellulosic waste conversion - A comprehensive review. Biotechnol Adv 2024; 71:108308. [PMID: 38211664 DOI: 10.1016/j.biotechadv.2024.108308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Revised: 12/14/2023] [Accepted: 01/04/2024] [Indexed: 01/13/2024]
Abstract
The rumen of ruminants is a natural anaerobic fermentation system that efficiently degrades lignocellulosic biomass and mainly depends on synergistic interactions between multiple microbes and their secreted enzymes. Ruminal microbes have been employed as biomass waste converters and are receiving increasing attention because of their degradation performance. To explore the application of ruminal microbes and their secreted enzymes in biomass waste, a comprehensive understanding of these processes is required. Based on the degradation capacity and mechanism of ruminal microbes and their secreted lignocellulose enzymes, this review concentrates on elucidating the main enzymatic strategies that ruminal microbes use for lignocellulose degradation, focusing mainly on polysaccharide metabolism-related gene loci and cellulosomes. Hydrolysis, acidification, methanogenesis, interspecific H2 transfer, and urea cycling in ruminal metabolism are also discussed. Finally, we review the research progress on the conversion of biomass waste into biofuels (bioethanol, biohydrogen, and biomethane) and value-added chemicals (organic acids) by ruminal microbes. This review aims to provide new ideas and methods for ruminal microbe and enzyme applications, biomass waste conversion, and global energy shortage alleviation.
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Affiliation(s)
- Jinsong Liang
- School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300130, China
| | - Ru Zhang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Jianning Chang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Le Chen
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Mohammad Nabi
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Haibo Zhang
- College of Resources and Environment, Shanxi Agricultural University, Taigu 030801, China
| | - Guangming Zhang
- School of Energy & Environmental Engineering, Hebei University of Technology, Tianjin 300130, China.
| | - Panyue Zhang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
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Zhao Y, Yu S, Tan J, Wang Y, Li L, Zhao H, Liu M, Jiang L. Bioconversion of citrus waste by long-term DMSO-cryopreserved rumen fluid to volatile fatty acids and biogas is feasible: A microbiome perspective. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 351:119693. [PMID: 38042069 DOI: 10.1016/j.jenvman.2023.119693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 11/07/2023] [Accepted: 11/21/2023] [Indexed: 12/04/2023]
Abstract
Preserving rumen fluid as the inoculum for anaerobic digestion of food waste is necessary when access to animal donors or slaughterhouses is limited. This study aims to compare two preservation methods relative to fresh ruminal inoculum: (1) cryoprotected with 5% dimethyl sulfoxide (DMSO) and stored at -20 °C and (2) frozen at -20 °C, both for 6 months. The fermentation activity of different inoculum was evaluated by rumen-based in vitro anaerobic fermentation tests (volatile fatty acids, biomass digestibility, and gas production). Citrus pomace was used as the substrate during a 96-h fermentation. The maximum volatile fatty acids, methane production, and citrus pomace digestibility from fresh rumen fluid were not significantly different from rumen fluid preserved with DMSO. Metagenome analysis revealed a significant difference in the rumen microbial composition and functions between fresh rumen fluid and frozen inoculum without DMSO. Storage of rumen fluid using -20 °C with DMSO demonstrated the less difference compared with fresh rumen fluid in microbial alpha diversity and taxa composition. The hierarchical clustering tree of CAZymes showed that DMSO cryoprotected fluid was clustered much closer to the fresh rumen fluid, showing more similarity in CAZyme profiles than frozen rumen fluid. The abundance of functional genes associated with carbohydrate metabolism and methane metabolism did not differ between fresh rumen fluid and the DMSO-20 °C, whereas the abundance of key functional genes significantly decreased in frozen rumen fluid. These findings suggest that using rumen liquid preserved using DMSO at -20 °C for 180 days is a feasible alternative to fresh rumen fluid. This would reduce the need for laboratories to maintain animal donors and/or reduce the frequency of collecting rumen fluid from slaughterhouses.
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Affiliation(s)
- Yuchao Zhao
- College of Animal Science and Technology, Beijing University of Agriculture, Beijing, 102206, China
| | - Shiqiang Yu
- College of Animal Science and Technology, Beijing University of Agriculture, Beijing, 102206, China
| | - Jian Tan
- College of Animal Science and Technology, Beijing University of Agriculture, Beijing, 102206, China
| | - Ying Wang
- College of Animal Science and Technology, Beijing University of Agriculture, Beijing, 102206, China
| | - Liuxue Li
- College of Animal Science and Technology, Beijing University of Agriculture, Beijing, 102206, China
| | - Huiying Zhao
- College of Animal Science and Technology, Beijing University of Agriculture, Beijing, 102206, China
| | - Ming Liu
- College of Animal Science and Technology, Beijing University of Agriculture, Beijing, 102206, China
| | - Linshu Jiang
- College of Animal Science and Technology, Beijing University of Agriculture, Beijing, 102206, China.
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Zhang H, Zhang W, Wang S, Zhu Z, Dong H. Microbial composition play the leading role in volatile fatty acid production in the fermentation of different scale of corn stover with rumen fluid. Front Bioeng Biotechnol 2024; 11:1275454. [PMID: 38239916 PMCID: PMC10794738 DOI: 10.3389/fbioe.2023.1275454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 11/27/2023] [Indexed: 01/22/2024] Open
Abstract
Rumen fluid is a natural and green biocatalyst that can efficiently degrade biomass into volatile fatty acid (VFA) used to produce value-added materials. But the essence of high degradation efficiency in the rumen has not been fully analyzed. This study investigated the contribution of substrate structure and microbial composition to volatile fatty acid production in the fermentation of corn stover. The ball milled corn stover were innovatively applied to ferment with the rumen fluid collected at different digestion times. Exogeneous cellulase was also added to the ruminal fermentation to further reveal the inner mechanism. With prolonged digestion time, the microbial community relative abundance levels of Bacteroidetes and Firmicutes increased from 29.98% to 72.74% and decreased from 51.76% to 22.11%, respectively. The highest VFA production of the corn stover was achieved via treatment with the rumen fluid collected at 24 h which was up to 9508 mg/L. The ball milled corn stover achieved high VFA production because of the more accessible substrate structure. The application of exogenous cellulase has no significant influence to the ruminal fermentation. The microbial community abundance contributed more to the VFA production compared with the substrate structures.
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Affiliation(s)
- Haiyan Zhang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Wanqin Zhang
- China Huadian Engineering Co., Ltd., Beijing, China
| | - Shunli Wang
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Zhiping Zhu
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Hongmin Dong
- Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing, China
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Degradation of Cellulose and Hemicellulose by Ruminal Microorganisms. Microorganisms 2022; 10:microorganisms10122345. [PMID: 36557598 PMCID: PMC9785684 DOI: 10.3390/microorganisms10122345] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 11/19/2022] [Accepted: 11/26/2022] [Indexed: 11/29/2022] Open
Abstract
As major structural components of plant cell walls, cellulose and hemicellulose are degraded and fermented by anaerobic microbes in the rumen to produce volatile fatty acids, the main nutrient source for the host. Cellulose degradation is carried out primarily by specialist bacteria, with additional contributions from protists and fungi, via a variety of mechanisms. Hemicelluloses are hydrolyzed by cellulolytic bacteria and by generalist, non-cellulolytic microbes, largely via extracellular enzymes. Cellulose hydrolysis follows first-order kinetics and its rate is limited by available substrate surface area. Nevertheless, its rate is at least an order of magnitude more rapid than in anaerobic digesters, due to near-obligatory adherence of microbial cells to the cellulose surface, and a lack of downstream inhibitory effects; in the host animal, fiber degradation rate is also enhanced by the unique process of rumination. Cellulolytic and hemicellulolytic microbes exhibit intense competition and amensalism, but they also display mutualistic interactions with microbes at other trophic levels. Collectively, the fiber-degrading community of the rumen displays functional redundancy, partial niche overlap, and convergence of catabolic pathways that all contribute to stability of the ruminal fermentation. The superior hydrolytic and fermentative capabilities of ruminal fiber degraders make them promising candidates for several fermentation technologies.
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Methane Production Potential from Apple Pomace, Cabbage Leaves, Pumpkin Residue and Walnut Husks. APPLIED SCIENCES-BASEL 2022. [DOI: 10.3390/app12126128] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Circular economy aims to eliminate organic waste through its transformation, composting and processing into other products or energy. The main aim of the study was to determine the specific methane yield (SMY) of anaerobic digestion (AD) of four different fruit and vegetable residues (FVR). In addition, the reduction in greenhouse gas (GHG) emissions was calculated based on the assumption that maize will be replaced by the FVR as a feedstock for biogas production. The SMY of four residues (apple pomace, cabbage leaves, pumpkin peels and fibrous strands and walnut husks) was measured in the biomethane potential test (BMP) in wet anaerobic digestion technology. The highest SMY (297.81 ± 0.65 NL kgVS−1) was observed for cabbage leaves while the lowest SMY (131.07 ± 1.30 kgVS−1) was found for walnut husks. The concentrations of two inhibitory gasses (NH3 and H2S) in biogas were low and did not affect the AD process. Only biogas produced from cabbage leaves was characterised by higher NH3 and H2S concentrations resulting from the highest protein concentration in this waste. FVR used as feedstock in biogas production may decrease the area of maize cultivation. Therefore, the GHG emissions from maize cultivation will be reduced. In Poland only, the use of four studied FVR as feedstock for biogas production would contribute to the reduction of GHG emissions by 43,682 t CO2 eq.
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Nutritional Value, Fermentation Characteristics and In Vitro Degradability of Whole Wheat Hay Harvested at Three Stages of Maturity. Animals (Basel) 2022; 12:ani12111466. [PMID: 35681930 PMCID: PMC9179648 DOI: 10.3390/ani12111466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 05/29/2022] [Accepted: 05/31/2022] [Indexed: 12/04/2022] Open
Abstract
The nutritional value of whole crop wheat hay (WCWH) harvested at different maturation stages are different, and its feeding effects on dairy cows have not been thoroughly evaluated. In this study, the in vitro digestibility of whole wheat (Nongda 22) hay harvested during the flowering, late milk and dough stages were evaluated using batch culture technique. The neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of whole wheat hay decreased by 35.5% and 40.4%, respectively, whereas the non-fibrous carbohydrates (NFC) content increased by 50.3% in WCWH harvested during the dough stage as compared to the flowering stage (p < 0.01). The pH of the fermentation liquid and acetate to propionate ratio was greatest in the wheat harvested during the flowering stage and lowest during the dough stage (p = 0.03), whereas the volatile fatty acid (VFA) concentration was greatest during the dough stage and lowest during the flowering stage (p < 0.01). The dry matter loss (DML) was 9.6% and 6.2% greater (p < 0.01) during the late milk stage than in the flowering or dough stages, and the NDF loss (NDFL; p = 0.01) and ADF loss (ADFL; p < 0.01) was greater in both the flowering and late milk stages. In conclusion, though the content of NDF was lower in the dough stage, and the starch to NFC ratio was greater, we determined that the optimal harvest stage should be the late milk stage due to the greater dry matter digestibility, the relatively greater NFC content and the shorter planting days.
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Holtzapple MT, Wu H, Weimer PJ, Dalke R, Granda CB, Mai J, Urgun-Demirtas M. Microbial communities for valorizing biomass using the carboxylate platform to produce volatile fatty acids: A review. BIORESOURCE TECHNOLOGY 2022; 344:126253. [PMID: 34728351 DOI: 10.1016/j.biortech.2021.126253] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 10/23/2021] [Accepted: 10/26/2021] [Indexed: 06/13/2023]
Abstract
The carboxylate platform employs a diverse microbial consortium of anaerobes in which the methanogens are inhibited. Nearly all biomass components are digested to a mixture of C1-C8 monocarboxylic acids and their corresponding salts. The methane-arrested anaerobic digestion proceeds readily without needing to sterilize biomass or equipment. It accepts a wide range of feedstocks (e.g., agricultural residues, municipal solid waste, sewage sludge, animal manure, food waste, algae, and energy crops), and produces high product yields. This review highlights several important aspects of the platform, including its thermodynamic underpinnings, influences of inoculum source and operating conditions on product formation, and downstream chemical processes that convert the carboxylates to hydrocarbon fuels and oxygenated chemicals. This review further establishes the carboxylate platform as a viable and economical route to industrial biomass utilization.
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Affiliation(s)
- Mark T Holtzapple
- Department of Chemical Engineering, Texas A&M University, College Station, TX 77843-3122, USA
| | - Haoran Wu
- Department of Chemical Engineering, Texas A&M University, College Station, TX 77843-3122, USA; Applied Materials Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, IL 60439, USA
| | - Paul J Weimer
- Department of Bacteriology, University of Wisconsin at Madison, Madison, WI 53706, USA
| | - Rachel Dalke
- Applied Materials Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, IL 60439, USA
| | - Cesar B Granda
- Department of Chemical Engineering, Texas A&M University, College Station, TX 77843-3122, USA
| | - Jesse Mai
- Applied Materials Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, IL 60439, USA
| | - Meltem Urgun-Demirtas
- Applied Materials Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, IL 60439, USA.
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Potential Valorization of Organic Waste Streams to Valuable Organic Acids through Microbial Conversion: A South African Case Study. Catalysts 2021. [DOI: 10.3390/catal11080964] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The notion of a “biobased economy” in the context of a developing country such as South Africa (SA) necessitates the development of technologies that utilize sustainable feedstocks, have simple and robust operations, are feasible at small scale and produce a variety of valuable bioproducts, thus fitting the biorefinery concept. This case study focuses on the microbial production of higher-value products from selected organic waste streams abundant in the South African agricultural sector using microbes adapted to utilize different parts of biomass waste streams. A ruminant-based carboxylate platform based on mixed or undefined anaerobic co-cultures of rumen microorganisms can convert the carbohydrate polymers in the lignocellulosic part of organic waste streams to carboxylic acids that can be upgraded to biofuels or green chemicals. Furthermore, yeast and fungi can convert the simpler carbohydrates (such as the sugars and malic acid in grape and apple pomace) to ethanol and high-value carboxylic acids, such as lactic, fumaric, succinic and citric acid. This review will discuss the combinational use of the ruminal carboxylate platform and native or recombinant yeasts to valorize biomass waste streams through the production of higher-value organic acids with various applications.
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Liu H, Qin S, Sirohi R, Ahluwalia V, Zhou Y, Sindhu R, Binod P, Rani Singhnia R, Kumar Patel A, Juneja A, Kumar D, Zhang Z, Kumar J, Taherzadeh MJ, Kumar Awasthi M. Sustainable blueberry waste recycling towards biorefinery strategy and circular bioeconomy: A review. BIORESOURCE TECHNOLOGY 2021; 332:125181. [PMID: 33888357 DOI: 10.1016/j.biortech.2021.125181] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 04/09/2021] [Accepted: 04/10/2021] [Indexed: 06/12/2023]
Abstract
Waste valorization using biological methods for value addition as well as environmental management is becoming popular approach for sustainable development. The present review addresses the availability of blueberry crop residues (BCR), applications of this feedstock in bioprocess for obtaining range of value-added products, to offer economic viability, business development and market potential, challenges and future perspectives. To the best of our knowledge, this is the first article addressing the blueberry waste valorization for a sustainable circular bioeconomy. Furthermore, it covers the information on the alternative BCR valorization methods and production of biochar for environmental management through removal or mitigation of organic and inorganic pollutants from contaminated sites. The review also discusses the ample opportunities of strategic utilization of BCR to offer solutions for environmental sustenance, covers the emerging trends to produce multi-products and techno-economic prospective for sustainable agronomy.
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Affiliation(s)
- Huimin Liu
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China
| | - Shiyi Qin
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China
| | - Ranjna Sirohi
- Department of Chemical and Biological Engineering, Korea University, Seoul, South Korea
| | - Vivek Ahluwalia
- Institute of Pesticide Formulation Technology, Gurugram, Haryana 122 016, India
| | - Yuwen Zhou
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China
| | - Raveendran Sindhu
- Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Thiruvananthapuram, Kerala 695019, India
| | - Parameswaran Binod
- Microbial Processes and Technology Division, CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Thiruvananthapuram, Kerala 695019, India
| | - Reeta Rani Singhnia
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Anil Kumar Patel
- Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, Taiwan
| | - Ankita Juneja
- Department of Agricultural and Biological Engineering, University of Illinois at Urbana Champaign, 1304 W. Pennsylvania Avenue, Urbana, IL 61801, USA
| | - Deepak Kumar
- Department of Chemical Engineering, SUNY College of Environmental Science and Forestry, 402 Walters Hall, 1 Forestry Drive, Syracuse, NY 13210, USA
| | - Zengqiang Zhang
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China
| | - Jitendra Kumar
- Institute of Pesticide Formulation Technology, Gurugram, Haryana 122 016, India
| | | | - Mukesh Kumar Awasthi
- College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi Province 712100, PR China; Swedish Centre for Resource Recovery, University of Borås, Borås 50190, Sweden.
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