Utilization of sugarcane straw for production of β-glucan biopolymer by Lasiodiplodia theobromae CCT 3966 in batch fermentation process

beta-Glucans as emerging biopolymer are widely produced by microorganisms in fermentation processes using commercial sugars which make process non-economic. Lignocellulosic substances are inexpensive carbon sources, which could be exploited for sustainable production of beta-glucans. In this study, a lignocellulosic material, namely sugarcane straw (SCS) was utilized for the production of extracellular beta-glucan by Lasiodiplodia theobromae CCT3966. SCS was subjected to acid and subsequent alkaline pretreatment, followed by enzymatic saccharification using cellulase enzyme. Quantity of 48.65 g/L glucose was released after enzymatic hydrolysis. beta-Glucan production was performed by cultivation of fungal strain in SCS hydrolysate at 28 degrees C and initial culture pH 7. Highest beta-glucan yield and productivity of 0.047 gg(-1) and 0.014 gL(-1) h(-1), respectively was obtained at 72 h fermentation time. Kinetic study of beta-glucan production revealed experimental biosynthesis of beta-glucan from SCS hydrolysate followed the trend generated by Logistic and Luedeking-Piret models. Chemical structure of biopolymer produced showed beta-glucan constitution.