Conclusive selection of optimal parameters for cellulase production by <i>Talaromyces verruculosus</i> IIPC 324 under SSF via saccharification of acid-pretreated sugarcane bagasse

<p>Cellulase production studies were conducted with <i>Talaromyces verruculosus</i> IIPC 324 under solid state fermentation (SSF), and optimal parameters were conclusively selected via saccharification of acid-pretreated sugarcane bagasse. Various physicochemical parameters affecting cellulase production under SSF were optimized. Endoglucanase and cellobiase production responded differently under individual growth conditions. Maximum endoglucanase and cellobiase activity of ≥ 250 U/g and ≥ 45 U/g respectively was obtained when the strain was grown at 24°C for 4 days with an initial moisture content of 62.5% on wheat bran supplemented with 1.62% ammonium chloride. The enzyme cocktail obtained from these optimized growth conditions yielded 8.37 ± 0.75 g L⁻¹ reducing sugar from acid-pretreated sugarcane bagasse after 72 h at 60°C and pH 4.0. With the addition of Avicel PH-101 at 5% concentration in wheat bran, the cellulase cocktail of <i>Talaromyces verruculosus</i> IIPC 324 released 9.17 ± 0.60 g L⁻¹ and 7.82 ± 0.06 g L⁻¹ of total reducing sugars and glucose respectively at 60°C (pH 4.0) after 72 h. The addition of glucose and other simple sugars did not repress the cellulase production under SSF conditions, making <i>Talaromyces verruculosus</i> IIPC 324 an attractive candidate for cellulase production and its application for biofuel production from lignocellulosic biomass.