2-Pyrrolidone synthesis from γ-aminobutyric acid produced by Lactobacillus brevis under solid-state fermentation utilizing toxic deoiled cottonseed cake

Abstract

There is an increasing demand of γ-aminobutyric acid (GABA) as drug and food additive, as well as feedstock to produce 2-pyrrolidone, a precursor for the synthesis of nylon 4. 2-Pyrrolidone is a petrochemical and depleting reserve which raises concern for its bio-based production. The study herein describes bio-based economical GABA production from Lactobacillus brevis by solid-state fermentation (SSF) using toxic deoiled cottonseed cake (CSC) as substrate. In general, the use of cottonseed cake remains restricted due to the presence of toxic gossypols. Thus, simultaneous detoxification observed during fermentation also widens the scope of utilization of this residual seedcake for feed use vis-a-vis production of other value added chemicals. The SSF conditions were optimized for maximum GABA production, viz., 19.7mg/g, CSC of GABA was obtained at 6th day of fermentation with 70% degradation of gossypols simultaneously. The potential of this bio-based GABA as a platform chemical is demonstrated in the synthesis of 2-pyrrolidone. Thus, a simple and cost-effective strategy for utilizing toxic biomass has been developed as an alternate to chemical synthetic route.