Screening and Identification of an Independent-glutamic Acid Strain Producing Poly(γ-glutamic acid)

Abstract:

17 strains of bacterium that produced a large amount of γ-PGA when it was grown aerobically in a culture medium containing ammonium salt and sugar as sources of nitrogen and carbon respectively，were isolated from bean products.With the following identifications of colony morphology，physiological and biochemistry experiments，and genetics，the strain PGA-O-7 was classified as a Bacillus subtilis.The PGA production 2.8 (mg/mL) was obtained when it was grown in a medium containing 3% ammonium sulfate and 4% glucose at 30℃ for 72h with sharking.