title: Highly efficient rice straw utilization for poly-(γ-glutamic acid) production by Bacillus subtilis NX-2.
abstract: Lignocellulosic biomass has been identified as an economic and environmental feedstock for future biotechnological production. Here, for the first time, poly-(γ-glutamic acid) (PGA) production by Bacillus subtilis NX-2 using rice straw is investigated. Based on two-stage hydrolysis and characteristic consumption of xylose and glucose by B. subtilis NX-2, a co-fermentation strategy was designed to better accumulate PGA in a 7.5L fermentor by two feeding methods. The maximum cumulative respective PGA production and PGA productivity were 73.0 ± 0.5 g L(-1) and 0.81 g L(-1) h(-1) by the continuous feeding method, with carbon source cost was saved by 84.2% and 42.5% compared with glucose and cane molasse, respectively. These results suggest that rice straw, a type of abundant, low-cost, non-food lignocellulosic feedstock, may be feasibly and efficiently utilized for industrial-scale production of PGA.
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
authors.forename: Bao
authors.initials: B
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Lei
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
authors.forename: Zongqi
authors.initials: Z
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
authors.forename: Yongxiang
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Xu
authors.affiliation: College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Liang
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China.
authors.forename: Xiaohai
authors.initials: X
authors.lastname: Feng
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 211816, China; College of Food Science and Light Industry, Nanjing Tech University, Nanjing 211816, China. Electronic address: xuh@njtech.edu.cn.
authors.forename: Hong
authors.initials: H
authors.lastname: Xu
mesh_terms: D001412:Bacillus subtilis / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D001709:Biotechnology / Q000191:economics / Q000379:methods*; D002244:Carbon / Q000494:pharmacology; D005285:Fermentation / Q000187:drug effects; D005947:Glucose / Q000494:pharmacology; D006868:Hydrolysis; D012275:Oryza / Q000187:drug effects / Q000378:metabolism*; D011099:Polyglutamic Acid / Q000096:biosynthesis*; D013997:Time Factors; D014866:Waste Products; D014994:Xylose / Q000494:pharmacology
chemical_list: D014866:Waste Products; D011099:Polyglutamic Acid; D002244:Carbon; D014994:Xylose; D005947:Glucose
keywords: Bacillus subtilis NX-2; Hydrolysis; Poly(γ-glutamic acid); Rice straw; Xylose