Glycoside hydrolase enhancement activities of Trichoderma harzianum P49P11 for sugarcane pretreated bagasse enzymatic hydrolysis using statistical optimization

Glycoside hydrolase complex (GHc) from Trichoderma harzianum P49P11 has being recently studied and its potential recognized to be applied in the enzymatic hydrolysis step for ethanol 2G production. The aim of this study was to enhance T. harzianum P49P11 GHc production in submerged fermentation. Central Compositive Rotational Design was used to study culture media composition to optimize GHc activities by testing the following media components: microcrystalline cellulose (CEL) (0-20g / L), sucrose (SUC) (0-10g / L) and wheat bran (WB) (0-15g / L). Five optimized culture media (two for FPase activity, two for β-glucosidase activity and one for xylanase activity) were then set up at 95% level of confidence. T. harzianum P49P11 was grown on shaking flasks on these culture media, supernatant were collected at 96h and produced GHc titer were carried out against 13 cellulosic and hemicellulosic substrates (Filter paper Whatman #1, CMC, Avicel, pNPG, β-glucan, lichenan, larch arabinan, sugar beet, beech wood xylan, pectin, 1,4 β-mannan, glucomannan and xyloglucan) relevant for EH and scored as the sum of the highest specific enzyme activity against those substrates. Highest score (6 out of 13 substrates) were obtained for GHc produced in culture media optimized for FPase (SUC = 0.0 g/L; CEL = 20.0 g/L; WF = 15.0 g/L) and for β-glucosidase (SUC = 0.0 g/L; CEL = 14.4 g/L; WB = 15.0 g/L). The enzymatic hydrolysis of delignified steam-exploded sugarcane bagasse using these GHc performed equally well (yield > 60% of monosaccharides glucose + xylose).