Lactic acid production from cashew apple bagasse, an agro-industrial waste, and its application in the enzymatic synthesis of polylactic acid

Abstract

The use of cashew apple bagasse hemicellulose hydrolysate (CABH) to produce lactic acid by two strains of lactic acid bacteria, Lactobacillus plantarum FJ05311 and L. plantarum FJ05315, was evaluated. The application of cashew apple bagasse (CAB) would enhance the establishment of a biorefinery from this agro-industrial residue since its main compounds, cellulose, hemicellulose, and lignin, can be used to obtain several bioproducts. The influence of essential parameters was studied for the production of LA. The CABH contained mainly glucose and xylose at concentrations of approximately 40 g/L and 20 g/L, respectively. The process conducted at 30 °C, 100 rpm, and using the culture in the final of the growth phase (inoculum time of 24 h for LAB07 and 20 h for LAB14) and urea as nitrogen source enhanced the LA production for both strains, LAB07 and LAB14, reaching 24.3 g/L. The produced LA was used to synthesize polylactic acid (PLA) for the enzymatic route using lipase B from Candida antarctica (CALB). Then, the production of PLA from cashew apple bagasse hydrolysate is a sustainable alternative to produce a biodegradable polymer with many industrial applications and obtaining personal protective equipment to use in the current and future pandemics.