Regulation Method for Preparing Gamma-Polyglutamic Acid by Sludge Substrate Fermentation

摘要

A regulation method for preparing γ-polyglutamic acid by sludge substrate fermentation includes: 1) extraction of glutamic acid from sludge protein (high pressure hydrothermal treatment, gravity pressure filtration treatment), 2) secondary metabolic synthesis of γ-polyglutamic acid (activation of domesticated strains and secondary metabolic fermentation strains); and 3) preparation of pure γ-polyglutamic acid (acidification, centrifugation, filtration, precipitation based on polar repulsion, purification, impurity removal and drying). The present invention realizes a recycling of high-value carbon and nitrogen sources of sludge without secondary pollution, and has advantages of simplified operation, good feasibility, and low preparation cost. The synthesized γ-polyglutamic acid has high economic value and broad application prospect.