title: Biological pretreatment of rice straw with Streptomyces griseorubens JSD-1 and its optimized production of cellulase and xylanase for improved enzymatic saccharification efficiency.
abstract: Biological pretreatment of rice straw and production of reducing sugars by hydrolysis of bio-pretreated material with Streptomyces griseorubens JSD-1 was investigated. After 10 days of incubation, various chemical compositions of inoculated rice straw were degraded and used for further enzymatic hydrolysis studies. The production of cellulolytic enzyme by S. griseorubens JSD-1 favored the conversion of cellulose to reducing sugars. The culture medium for cellulolytic enzyme production by using agro-industrial wastes was optimized through response surface methodology. According to the response surface analysis, the concentrations of 11.13, 20.34, 4.61, and 2.85 g L(-1) for rice straw, wheat bran, peptone, and CaCO3, respectively, were found to be optimum for cellulase and xylanase production. Then the hydrolyzed spent Streptomyces cells were used as a nitrogen source and the maximum filter paper cellulase, carboxymethylcellulase, and xylanase activities of 25.79, 78.91, and 269.53 U mL(-1) were achieved. The crude cellulase produced by S. griseorubens JSD-1 was subsequently used for the hydrolysis of bio-pretreated rice straw, and the optimum saccharification efficiency of 88.13% was obtained, indicating that the crude enzyme might be used instead of commercial cellulase during a saccharification process. These results give a basis for further study of bioethanol production from agricultural cellulosic waste.
authors.affiliation: a Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology , Shanghai Jiaotong University , Shanghai , China.
authors.forename: Dan
authors.initials: D
authors.lastname: Zhang
authors.affiliation: a Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology , Shanghai Jiaotong University , Shanghai , China.
authors.forename: Yanqing
authors.initials: Y
authors.lastname: Luo
authors.affiliation: a Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology , Shanghai Jiaotong University , Shanghai , China.
authors.forename: Shaohua
authors.initials: S
authors.lastname: Chu
authors.affiliation: a Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology , Shanghai Jiaotong University , Shanghai , China.
authors.forename: Yuee
authors.initials: Y
authors.lastname: Zhi
authors.affiliation: a Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology , Shanghai Jiaotong University , Shanghai , China.
authors.forename: Bin
authors.initials: B
authors.lastname: Wang
authors.affiliation: a Key Laboratory of Urban Agriculture (South) Ministry of Agriculture, School of Agriculture and Biology , Shanghai Jiaotong University , Shanghai , China.
authors.forename: Pei
authors.initials: P
authors.lastname: Zhou
mesh_terms: D050260:Carbohydrate Metabolism; D002480:Cellulase / Q000096:biosynthesis*; D003470:Culture Media; D043364:Endo-1,4-beta Xylanases / Q000096:biosynthesis*; D005285:Fermentation; D006868:Hydrolysis; D012275:Oryza; D013302:Streptomyces / Q000201:enzymology*
chemical_list: D003470:Culture Media; D002480:Cellulase; D043364:Endo-1,4-beta Xylanases
keywords: Bio-pretreatment; cellulase; enzymatic hydrolysis; response surface methodology; rice straw; xylanase