title: Optimization of the production of poly-γ-glutamic acid by Bacillus amyloliquefaciens C1 in solid-state fermentation using dairy manure compost and monosodium glutamate production residues as basic substrates.
abstract: Poly-γ-glutamic acid (γ-PGA) is a polymer with uses in foods, cosmetics, medicine and agriculture. The medium for the production of γ-PGA by Bacillusamyloliquefaciens C1 was optimized by response surface methodology using agro-industrial wastes in solid-state fermentation (SSF). The optimal SSF medium (20g substrates with 50% initial moisture) for producing γ-PGA was determined to contain 5.51g dairy manure compost, 1.91g soybean cake, 0.57g corn flour, 2.15g monosodium glutamate production residues, 1.5g wheat bran, 0.5g rapeseed cake, 0.1g citric acid, 0.05g MgSO(4)·7H(2)O and 0.03g MnSO(4)·H(2)O. In this medium the strain produced up to 0.0437g γ-PGA per gram of substrates when cultured for 48h at 37°C. SDS-PAGE showed that the molecular weight of the γ-PGA was more than 130kDa. Due to the high-yields observed and the low-cost nature of the optimal medium, this study indicates a possibility to establish economical large-scale production of γ-PGA.
authors.affiliation: Jiangsu Provincial Key Laboratory for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing 210095, China.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Yong
authors.forename: Waseem
authors.initials: W
authors.lastname: Raza
authors.forename: Guanghui
authors.initials: G
authors.lastname: Yu
authors.forename: Wei
authors.initials: W
authors.lastname: Ran
authors.forename: Qirong
authors.initials: Q
authors.lastname: Shen
authors.forename: Xingming
authors.initials: X
authors.lastname: Yang
mesh_terms: D000818:Animals; D001407:Bacillus / Q000378:metabolism*; D002417:Cattle; D003612:Dairying; D004591:Electrophoresis, Polyacrylamide Gel; D005285:Fermentation; D007220:Industrial Waste; D008372:Manure; D011099:Polyglutamic Acid / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000737:chemistry; D012970:Sodium Glutamate / Q000378:metabolism; D012987:Soil / Q000737:chemistry*
chemical_list: D007220:Industrial Waste; D008372:Manure; D012987:Soil; C511775:poly(gamma-glutamic acid); D011099:Polyglutamic Acid; D012970:Sodium Glutamate