Production of Biodegradable Polymer from Agro-Wastes in Alcaligenes sp. and Pseudomonas sp.

Abstract

The present study was aimed to evaluate the suitability of agro-wastes and crude vegetable oils for the cost-effective production of poly-β-hydroxybutyrate (PHB), to evaluate growth kinetics and PHB production in <i>Alcaligenes faecalis</i> RZS4 and <i>Pseudomonas</i> sp. RZS1 with these carbon substrates and to study the biodegradation of PHB accumulated by these cultures. <i>Alcaligenes faecalis</i> RZS4 and <i>Pseudomonas</i> sp. RZS1 accumulates higher amounts of PHB corn (79.90% of dry cell mass) and rice straw (66.22% of dry cell mass) medium respectively. The kinetic model suggests that the <i>Pseudomonas</i> sp. RZS1 follows the Monod model more closely than <i>A. faecalis</i> RZS4. Both the cultures degrade their PHB extract under the influence of PHB depolymerase. Corn waste and rice straw appear as the best and cost-effective substrates for the sustainable production of PHB from <i>Alcaligenes faecalis</i> RZS4 and <i>Pseudomonas</i> sp. RZS1. The biopolymer accumulated by these organisms is biodegradable in nature. The agro-wastes and crude vegetable oils are good and low-cost sources of nutrients for the growth and production of PHB and other metabolites. Their use would lower the production cost of PHB and the low-cost production will reduce the sailing price of PHB-based products. This would promote the large-scale commercialization and popularization of PHB as an ecofriendly bioplastic/biopolymer.