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Lipid production from corn stover by the oleaginous yeast Cryptococcus curvatus

BACKGROUND: Microbial lipids produced from lignocellulosic biomass hold great promise for the biodiesel industry. These lipids usually consist of three major processes: pretreatment, enzymatic hydrolysis and lipid production. However, the conventional strategy of using biomass hydrolysates as the fe...

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Autores principales: Gong, Zhiwei, Shen, Hongwei, Yang, Xiaobing, Wang, Qian, Xie, Haibo, Zhao, Zongbao K
Formato: Online Artículo Texto
Lenguaje:English
Publicado: BioMed Central 2014
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4210566/
https://www.ncbi.nlm.nih.gov/pubmed/25352914
http://dx.doi.org/10.1186/s13068-014-0158-y
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author Gong, Zhiwei
Shen, Hongwei
Yang, Xiaobing
Wang, Qian
Xie, Haibo
Zhao, Zongbao K
author_facet Gong, Zhiwei
Shen, Hongwei
Yang, Xiaobing
Wang, Qian
Xie, Haibo
Zhao, Zongbao K
author_sort Gong, Zhiwei
collection PubMed
description BACKGROUND: Microbial lipids produced from lignocellulosic biomass hold great promise for the biodiesel industry. These lipids usually consist of three major processes: pretreatment, enzymatic hydrolysis and lipid production. However, the conventional strategy of using biomass hydrolysates as the feedstock for lipid production suffers from low lipid coefficient and prohibitively high costs. More cost-effective and integrated processes are required to advance lignocellulosic biomass-based microbial lipid technology. RESULTS: Three different strategies were tested using the oleaginous yeast Cryptococcus curvatus ATCC 20509 as a lipid producer and alkaline-pretreated corn stover as a model material. It was found that the separate hydrolysis and enhanced lipid production process required more cellulolytic enzymes yet afforded a low lipid coefficient of 115.6 mg/g pretreated corn stover. When biomass hydrolysis and lipid production were integrated, the amounts of cellulase and xylanase were reduced and no β-glucosidase was required. The simultaneous saccharification and lipid production process gave a lipid coefficient of 129.4 mg/g pretreated corn stover. A higher lipid coefficient of 159.4 mg/g pretreated corn stover was obtained using the simultaneous saccharification and enhanced lipid production (SSELP) process. Furthermore, cellulolytic enzymes were found recoverable and reusable upon recycling the spent supernatants of the SSELP process, which could reduce enzyme consumption and wastewater discharge. CONCLUSIONS: The SSELP process was superior to other processes in terms of converting alkaline-pretreated corn stover into lipids by C. curvatus, as it required less cellulolytic enzymes and had a higher lipid coefficient. Moreover, the process facilitated easy enzyme recycling that should lead to further reduction of enzyme consumption. These results provide valuable information for cost-effective lipid production from lignocelluloses, which should be particularly important in achieving a sustainable production of biodiesel.
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spelling pubmed-42105662014-10-29 Lipid production from corn stover by the oleaginous yeast Cryptococcus curvatus Gong, Zhiwei Shen, Hongwei Yang, Xiaobing Wang, Qian Xie, Haibo Zhao, Zongbao K Biotechnol Biofuels Research Article BACKGROUND: Microbial lipids produced from lignocellulosic biomass hold great promise for the biodiesel industry. These lipids usually consist of three major processes: pretreatment, enzymatic hydrolysis and lipid production. However, the conventional strategy of using biomass hydrolysates as the feedstock for lipid production suffers from low lipid coefficient and prohibitively high costs. More cost-effective and integrated processes are required to advance lignocellulosic biomass-based microbial lipid technology. RESULTS: Three different strategies were tested using the oleaginous yeast Cryptococcus curvatus ATCC 20509 as a lipid producer and alkaline-pretreated corn stover as a model material. It was found that the separate hydrolysis and enhanced lipid production process required more cellulolytic enzymes yet afforded a low lipid coefficient of 115.6 mg/g pretreated corn stover. When biomass hydrolysis and lipid production were integrated, the amounts of cellulase and xylanase were reduced and no β-glucosidase was required. The simultaneous saccharification and lipid production process gave a lipid coefficient of 129.4 mg/g pretreated corn stover. A higher lipid coefficient of 159.4 mg/g pretreated corn stover was obtained using the simultaneous saccharification and enhanced lipid production (SSELP) process. Furthermore, cellulolytic enzymes were found recoverable and reusable upon recycling the spent supernatants of the SSELP process, which could reduce enzyme consumption and wastewater discharge. CONCLUSIONS: The SSELP process was superior to other processes in terms of converting alkaline-pretreated corn stover into lipids by C. curvatus, as it required less cellulolytic enzymes and had a higher lipid coefficient. Moreover, the process facilitated easy enzyme recycling that should lead to further reduction of enzyme consumption. These results provide valuable information for cost-effective lipid production from lignocelluloses, which should be particularly important in achieving a sustainable production of biodiesel. BioMed Central 2014-10-23 /pmc/articles/PMC4210566/ /pubmed/25352914 http://dx.doi.org/10.1186/s13068-014-0158-y Text en © Gong et al.; licensee BioMed Central Ltd. 2014 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
spellingShingle Research Article
Gong, Zhiwei
Shen, Hongwei
Yang, Xiaobing
Wang, Qian
Xie, Haibo
Zhao, Zongbao K
Lipid production from corn stover by the oleaginous yeast Cryptococcus curvatus
title Lipid production from corn stover by the oleaginous yeast Cryptococcus curvatus
title_full Lipid production from corn stover by the oleaginous yeast Cryptococcus curvatus
title_fullStr Lipid production from corn stover by the oleaginous yeast Cryptococcus curvatus
title_full_unstemmed Lipid production from corn stover by the oleaginous yeast Cryptococcus curvatus
title_short Lipid production from corn stover by the oleaginous yeast Cryptococcus curvatus
title_sort lipid production from corn stover by the oleaginous yeast cryptococcus curvatus
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4210566/
https://www.ncbi.nlm.nih.gov/pubmed/25352914
http://dx.doi.org/10.1186/s13068-014-0158-y
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