title: Economical production of poly(γ-glutamic acid) using untreated cane molasses and monosodium glutamate waste liquor by Bacillus subtilis NX-2.
abstract: The production of poly(γ-glutamic acid) by Bacillus subtilis NX-2 from cane molasses and monosodium glutamate waste liquor (MGWL) was studied for the first time in this work. When batch fermentation was carried out with untreated molasses, 33.6±0.37 g L(-1) PGA was obtained with a productivity of 0.46±0.006 g L(-1) h(-1). In order to minimize the substrate inhibition, fed-batch fermentation was performed with untreated or hydrolyzed molasses in 7.5 L bioreactor, giving 50.2±0.53 and 51.1±0.51 g L(-1) of PGA at 96 h, respectively. Further studies were carried out by using MGWL as another carbon source, resulting in a PGA concentration of 52.1±0.52 g L(-1) with a productivity of 0.54±0.003 g L(-1) h(-1). These results suggest that the low-cost cane molasses and MGWL can be used for the environmental-friendly and economical production of PGA by B. subtilis NX-2.
authors.affiliation: State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing 210009, PR China.
authors.forename: Dan
authors.initials: D
authors.lastname: Zhang
authors.forename: Xiaohai
authors.initials: X
authors.lastname: Feng
authors.forename: Zhe
authors.initials: Z
authors.lastname: Zhou
authors.forename: Yang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Hong
authors.initials: H
authors.lastname: Xu
mesh_terms: D001412:Bacillus subtilis / Q000378:metabolism*; D019149:Bioreactors / Q000191:economics* / Q000382:microbiology; D002681:China; D007220:Industrial Waste / Q000191:economics / Q000517:prevention & control; D008965:Molasses / Q000191:economics* / Q000382:microbiology*; D011099:Polyglutamic Acid / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000191:economics; D031786:Saccharum / Q000382:microbiology; D012970:Sodium Glutamate / Q000191:economics* / Q000378:metabolism
chemical_list: D007220:Industrial Waste; C511775:poly(gamma-glutamic acid); D011099:Polyglutamic Acid; D012970:Sodium Glutamate