PMID- 29234464 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20220311 IS - 1754-6834 (Print) IS - 1754-6834 (Electronic) IS - 1754-6834 (Linking) VI - 10 DP - 2017 TI - Production of isoprene, one of the high-density fuel precursors, from peanut hull using the high-efficient lignin-removal pretreatment method. PG - 297 LID - 10.1186/s13068-017-0988-5 [doi] LID - 297 AB - BACKGROUND: Isoprene as the feedstock can be used to produce renewable energy fuels, providing an alternative to replace the rapidly depleting fossil fuels. However, traditional method for isoprene production could not meet the demands for low-energy consumption and environment-friendliness. Moreover, most of the previous studies focused on biofuel production out of lignocellulosic materials such as wood, rice straw, corn cob, while few studies concentrated on biofuel production using peanut hull (PH). As is known, China is the largest peanut producer in the globe with an extremely considerable amount of PH to be produced each year. Therefore, a novel, renewable, and environment-friendly pretreatment strategy to increase the enzymatic hydrolysis efficiency of cellulose and reduce the inhibitors generation was developed to convert PH into isoprene. RESULTS: The optimal pretreatment conditions were 100 degrees C, 60 min, 10% (w/v) solid loading with a 2:8 volume ratio of phosphoric acid and of hydrogen peroxide. In comparison with the raw PH, the hemicellulose and lignin were reduced to 85.0 and 98.0%, respectively. The cellulose-glucose conversion of pretreated PH reached up to 95.0% in contrast to that of the raw PH (19.1%). Only three kinds of inhibitors including formic acid, levulinic acid, and a little furfural were formed during the pretreatment process, whose concentrations were too low to inhibit the isoprene yield for Escherichia coli fermentation. Moreover, compared with the isoprene yield of pure glucose fermentation (298 +/- 9 mg/L), 249 +/- 6.7 and 294 +/- 8.3 mg/L of isoprene were produced using the pretreated PH as the carbon source by the engineered strain via separate hydrolysis and fermentation and simultaneous saccharification and fermentation (SSF) methods, respectively. The isoprene production via SSF had a 9.8% glucose-isoprene conversion which was equivalent to 98.8% of isoprene production via the pure glucose fermentation. CONCLUSIONS: The optimized phosphoric acid/hydrogen peroxide combination pretreatment approach was proved effective to remove lignin and hemicellulose from lignocellulosic materials. Meanwhile, the pretreated PH could be converted into isoprene efficiently in the engineered Escherichia coli. It is concluded that this novel strategy of isoprene production using lignocellulosic materials pretreated by phosphoric acid/hydrogen peroxide is a promising alternative to isoprene production using traditional way which can fully utilize non-renewable fossil sources. FAU - Wang, Sumeng AU - Wang S AD - Shandong Key Lab of Applied Mycology, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109 China. ISNI: 0000 0000 9526 6338. GRID: grid.412608.9 FAU - Wang, Zhaobao AU - Wang Z AD - Shandong Key Lab of Applied Mycology, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109 China. ISNI: 0000 0000 9526 6338. GRID: grid.412608.9 FAU - Wang, Yongchao AU - Wang Y AD - Shandong Key Lab of Applied Mycology, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109 China. ISNI: 0000 0000 9526 6338. GRID: grid.412608.9 FAU - Nie, Qingjuan AU - Nie Q AD - Foreign Languages School, Qingdao Agricultural University, Qingdao, 266109 China. ISNI: 0000 0000 9526 6338. GRID: grid.412608.9 FAU - Yi, Xiaohua AU - Yi X AD - Shandong Key Lab of Applied Mycology, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109 China. ISNI: 0000 0000 9526 6338. GRID: grid.412608.9 FAU - Ge, Wei AU - Ge W AD - Shandong Key Lab of Applied Mycology, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109 China. ISNI: 0000 0000 9526 6338. GRID: grid.412608.9 FAU - Yang, Jianming AU - Yang J AUID- ORCID: 0000-0002-3268-211X AD - Shandong Key Lab of Applied Mycology, College of Life Science, Qingdao Agricultural University, No. 700 Changcheng Road, Chengyang District, Qingdao, 266109 China. ISNI: 0000 0000 9526 6338. GRID: grid.412608.9 FAU - Xian, Mo AU - Xian M AD - CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101 China. GRID: grid.458500.c LA - eng PT - Journal Article DEP - 20171208 PL - England TA - Biotechnol Biofuels JT - Biotechnology for biofuels JID - 101316935 PMC - PMC5721603 OTO - NOTNLM OT - Enzymatic hydrolysis efficiency OT - Isoprene OT - Lignin removal OT - Peanut hull OT - Phosphoric acid/hydrogen peroxide OT - Pretreatment EDAT- 2017/12/14 06:00 MHDA- 2017/12/14 06:01 PMCR- 2017/12/08 CRDT- 2017/12/14 06:00 PHST- 2017/08/21 00:00 [received] PHST- 2017/12/02 00:00 [accepted] PHST- 2017/12/14 06:00 [entrez] PHST- 2017/12/14 06:00 [pubmed] PHST- 2017/12/14 06:01 [medline] PHST- 2017/12/08 00:00 [pmc-release] AID - 988 [pii] AID - 10.1186/s13068-017-0988-5 [doi] PST - epublish SO - Biotechnol Biofuels. 2017 Dec 8;10:297. doi: 10.1186/s13068-017-0988-5. eCollection 2017.