Preparation of Environmental Probiotic Factor -Polyglutamic Acid via Microbial Fermentation Using Baijiu Brewing Steamer Bottom Water as a Basic Substrate

Steamer bottom water is the main component of wastewater in the Baijiu industry, Find a suitable method to deal with and use the Steamer bottom water. A new, cheap raw material and process of gamma-PGA production were developed. In this study, the single factor and response surface design were used to optimize the medium and conditions for high-yield gamma-PGA by submerged fermentation of bottom pot water with the concentration of gamma-PGA as the detection object. The volatile components in fermentation broth were detected by GC-MS. The fermentation medium formula and addition amount were determined to be 60 g/L corn saccharification liquid, 8 g/L peptone, 1 g/L K2HPO4, and 0.04 g/L MnSO4 center dot H2O. The inoculation amount was 2%, 37 C-degrees, 150 r/min, and the fermentation was 72 h. The gamma-PGA yield was 48.29 g/L, which was 1.98 times higher than that before optimization. We detected 12 volatile substances in the fermentation broth, acetic acid, 2,3-butanedione, 2-methyl-butanoic acid, and acetoin were recognized as Plant probiotic factors. The N, P, K, and total nutrient (sum of N, P, and K) contents were 4100, 3405, 885, and 8390 mg/L, respectively; the number of viable Bacillus subtilis was 4.5 x 10(7) CFU/mL. Teamer bottom water of Baijiu brewing can completely replace water as a fermentation medium solvent to produce gamma-PGA. Moreover, the fermentation broth is a potential functional organic fertilizer.