Optimization of β-glucosidase, β-xylosidase and xylanase production by Colletotrichum graminicola under solid-state fermentation and application in raw sugarcane trash saccharification

• Published in: International journal of molecular sciences 2013-01, Vol.14 (2), p.2875-2902
• Main Authors: Zimbardi, Ana L R L, Sehn, Cesar, Meleiro, Luana P, Souza, Flavio H M, Masui, Douglas C, Nozawa, Monica S F, Guimarães, Luis H S, Jorge, João A, Furriel, Rosa P M
• Format: Article
• Language: English
• Subjects: Arachis hypogaea; Colletotrichum graminicola; Hypocrea jecorina; Triticum aestivum
• ISSN: 1422-0067; 1422-0067
• DOI: 10.3390/ijms14022875

Efficient, low-cost enzymatic hydrolysis of lignocellulosic residues is essential for cost-effective production of bioethanol. The production of β-glucosidase, β-xylosidase and xylanase by Colletotrichum graminicola was optimized using Response Surface Methodology (RSM). Maximal production occurred in wheat bran. Sugarcane trash, peanut hulls and corncob enhanced β-glucosidase, β-xylosidase and xylanase production, respectively. Maximal levels after optimization reached 159.3 ± 12.7 U g-1, 128.1 ± 6.4 U g-1 and 378.1 ± 23.3 U g-1, respectively, but the enzymes were produced simultaneously at good levels under culture conditions optimized for each one of them. Optima of pH and temperature were 5.0 and 65 °C for the three enzymes, which maintained full activity for 72 h at 50 °C and for 120 min at 60 °C (β-glucosidase) or 65 °C (β-xylosidase and xylanase). Mixed with Trichoderma reesei cellulases, C. graminicola crude extract hydrolyzed raw sugarcane trash with glucose yield of 33.1% after 48 h, demonstrating good potential to compose efficient cocktails for lignocellulosic materials hydrolysis.