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Wang Z, Wu S, Fan C, Zheng X, Zhang W, Wu D, Wang X, Kong H. Optimisation of enzymatic saccharification of wheat straw pre-treated with sodium hydroxide. Sci Rep 2021; 11:23234. [PMID: 34853397 PMCID: PMC8636468 DOI: 10.1038/s41598-021-02693-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 11/15/2021] [Indexed: 11/30/2022] Open
Abstract
To enhance the reducing sugar yield in enzymatic hydrolysis, various factors (NaOH concentration, solid content and pre-treatment time) that affect the pre-treatment process were investigated and evaluated based on the reducing sugar yield of the subsequent enzymatic hydrolysis. The enzymatic hydrolysis was based on the cellulase from Trichoderma reesi ATCC 26921, the optimum NaOH pre-treatment conditions were an NaOH concentration of 1.0% (w/w), a solid content of 5.0% (w/v) and a pre-treatment time of 60 min. Various parameters that affect the enzymatic hydrolysis of wheat straw, including the solid content, enzyme loading, pH and hydrolysis time, were investigated and optimized through a Box–Behnken design and response surface methodology. The predicted optimum conditions for enzymatic hydrolysis were a solid content of 8.0% (w/v), an enzyme loading of 35 FPU/g substrate, a temperature of 50 °C, a pH of 5.3 and a hydrolysis time of 96 h. The experimental result showed that the maximum reducing sugar yield was 60.73% (53.35% higher than the wheat straw without NaOH pre-treatment), which is in accordance with the predicted conditions.
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Affiliation(s)
- Zhiquan Wang
- School of Life and Environmental Science, Wenzhou University, Chashan, Wenzhou, 325035, People's Republic of China
| | - Suqing Wu
- School of Life and Environmental Science, Wenzhou University, Chashan, Wenzhou, 325035, People's Republic of China
| | - Chunzhen Fan
- School of Life and Environmental Science, Wenzhou University, Chashan, Wenzhou, 325035, People's Republic of China
| | - Xiangyong Zheng
- School of Life and Environmental Science, Wenzhou University, Chashan, Wenzhou, 325035, People's Republic of China.
| | - Wei Zhang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, Minhang, People's Republic of China
| | - Deyi Wu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, Minhang, People's Republic of China
| | - Xinze Wang
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, Minhang, People's Republic of China
| | - Hainan Kong
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, Minhang, People's Republic of China.
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Wongsirichot P, Muanruksa P, Kaewkannetra P, Winterburn J. Comprehensive optimization of tropical biomass hydrolysis for nitrogen-limited medium-chain polyhydroxyalkanoate synthesis. WASTE MANAGEMENT (NEW YORK, N.Y.) 2021; 128:221-231. [PMID: 34000692 DOI: 10.1016/j.wasman.2021.04.062] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 04/19/2021] [Accepted: 04/30/2021] [Indexed: 06/12/2023]
Abstract
Expanding the use of tropical biomass wastes for nitrogen-limited fermentation was investigated, specifically, the production of medium chain length polyhydroxyalkanoates. Comprehensive central composite design was conducted to assess pH, temperature, biomass solid loading, cellulase loading and amylase loading and their impact on the hydrolysis of palm, coconut and cassava wastes. Glucose yields of 33.3, 31.7 and 79.0% wt. with respect to total glucose were found for palm, coconut and cassava, respectively. Importantly, the impact on the total nitrogen derived during enzymatic hydrolysis of these tropical biomass was described for the first time. The level of nitrogen needs to be properly controlled as high nitrogen would result in low carbon to nitrogen ratio leading to low polyhydroxyalkanoates accumulation, but low nitrogen would hinder growth of the biopolymer producer. Maximum hydrolysate nitrogen, were 1.80, 1.55 and 0.871 g/l for palm, coconut and cassava, respectively. Using the surface responses, biomass media designed for high carbon-to-nitrogen were produced and validated using Pseudomonas putida. Low glucose-carbon to nitrogen were found for palm and coconut after scale-up, leading to the majority of their polyhydroxyalkanoates not being biomass-derived. However, cassava-derived biopolymers were successfully accumulated at 9.01 and 7.13% wt. for total medium chain length polyhydroxyalkanoates and 10-carbon polyhydroxyalkanoates, respectively. This study provides an important foundation for the expansion of tropical biomass wastes for biopolymer production and other nitrogen-limited applications in general.
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Affiliation(s)
- Phavit Wongsirichot
- Department of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom
| | - Papasanee Muanruksa
- Department of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom; Department of Biotechnology, Faculty of Technology, Khon Kaen University, Mitraphap Road, Meuang, Khon kaen 40002, Thailand
| | - Pakawadee Kaewkannetra
- Department of Biotechnology, Faculty of Technology, Khon Kaen University, Mitraphap Road, Meuang, Khon kaen 40002, Thailand
| | - James Winterburn
- Department of Chemical Engineering and Analytical Science, The University of Manchester, Oxford Road, Manchester M13 9PL, United Kingdom.
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Cheawchanlertfa P, Sutheeworapong S, Jenjaroenpun P, Wongsurawat T, Nookaew I, Cheevadhanarak S, Kosugi A, Pason P, Waeonukul R, Ratanakhanokchai K, Tachaapaikoon C. Clostridium manihotivorum sp. nov., a novel mesophilic anaerobic bacterium that produces cassava pulp-degrading enzymes. PeerJ 2020; 8:e10343. [PMID: 33240652 PMCID: PMC7676355 DOI: 10.7717/peerj.10343] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 10/20/2020] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND Cassava pulp is a promising starch-based biomasses, which consists of residual starch granules entrapped in plant cell wall containing non-starch polysaccharides, cellulose and hemicellulose. Strain CT4T, a novel mesophilic anaerobic bacterium isolated from soil collected from a cassava pulp landfill, has a strong ability to degrade polysaccharides in cassava pulp. This study explored a rarely described species within the genus Clostridium that possessed a group of cassava pulp-degrading enzymes. METHODS A novel mesophilic anaerobic bacterium, the strain CT4T, was identified based on phylogenetic, genomic, phenotypic and chemotaxonomic analysis. The complete genome of the strain CT4T was obtained following whole-genome sequencing, assembly and annotation using both Illumina and Oxford Nanopore Technology (ONT) platforms. RESULTS Analysis based on the 16S rRNA gene sequence indicated that strain CT4T is a species of genus Clostridium. Analysis of the whole-genome average amino acid identity (AAI) of strain CT4T and the other 665 closely related species of the genus Clostridium revealed a separated strain CT4T from the others. The results revealed that the genome consisted of a 6.3 Mb circular chromosome with 5,664 protein-coding sequences. Genome analysis result of strain CT4T revealed that it contained a set of genes encoding amylolytic-, hemicellulolytic-, cellulolytic- and pectinolytic enzymes. A comparative genomic analysis of strain CT4T with closely related species with available genomic information, C. amylolyticum SW408T, showed that strain CT4T contained more genes encoding cassava pulp-degrading enzymes, which comprised a complex mixture of amylolytic-, hemicellulolytic-, cellulolytic- and pectinolytic enzymes. This work presents the potential for saccharification of strain CT4T in the utilization of cassava pulp. Based on phylogenetic, genomic, phenotypic and chemotaxonomic data, we propose a novel species for which the name Clostridium manihotivorum sp. nov. is suggested, with the type strain CT4T (= TBRC 11758T = NBRC 114534T).
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Affiliation(s)
- Pattsarun Cheawchanlertfa
- School of Bioresources and Technology, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
| | - Sawannee Sutheeworapong
- Pilot Plant Development and Training Institute, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
| | - Piroon Jenjaroenpun
- Division of Bioinformatics and Data Management for Research, Department of Research and Development, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
- Department of Biomedical Informatics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Thidathip Wongsurawat
- Division of Bioinformatics and Data Management for Research, Department of Research and Development, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
- Department of Biomedical Informatics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Intawat Nookaew
- Department of Biomedical Informatics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA
- Department of Physiology and Biophysics, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Supapon Cheevadhanarak
- School of Bioresources and Technology, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
- Pilot Plant Development and Training Institute, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
| | - Akihiko Kosugi
- Biological Resources and Post-harvest Division, Japan International Research Center for Agricultural Sciences, Ibaraki, Japan
| | - Patthra Pason
- School of Bioresources and Technology, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
- Pilot Plant Development and Training Institute, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
| | - Rattiya Waeonukul
- School of Bioresources and Technology, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
- Pilot Plant Development and Training Institute, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
| | - Khanok Ratanakhanokchai
- School of Bioresources and Technology, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
| | - Chakrit Tachaapaikoon
- School of Bioresources and Technology, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
- Pilot Plant Development and Training Institute, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand
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