Production and characterization of biodegradable polymer-polyhydroxybutyrate from agricultural waste-sugarcane bagasse by the novel marine bacterium Klebsiella pneumoniae G1

Abstract

An unusual halotolerant Klebsiella pneumoniae G1 producing green biodegradable polymer polyhydroxybutyrate (PHB) was isolated from the soil samples of marine fields near GITAM University, Visakhapatnam. The strain grew at wide salinities (2–10 %) and pH ranges (5–10), hence called halo-acid-alkali-tolerant. The time course with the optimized parameters (glucose as carbon source) yielded 6.86 g/L of PHB. G1 was tested further for PHB production on sugarcane bagasse (SCB, 5 %) which displayed PHB production of 9 g/L (a 3.6-fold increase). Structural assessment studies (FTIR, NMR, DSC, and TGA) confirmed the presence of PHB. This is the first report of producing high titers of PHB by G1 using SCB. The strain is advantageous to upscale the PHB production using SCB wastes for valorization.