Selection and Characterization of a Native Pycnoporus sanguineus Strain as a Lignocellulolytic Extract Producer from Submerged Cultures of Various Agroindustrial Wastes

A native strain of Pycnoporus sanguineus (CS2) was selected because of its lignocellulolytic potential on a color-based agar plate screening system; pectinolytic and amylolytic capabilities were also assessed. The effects of different lignocellulosic substrates under submerged cultures of selected fungi on the enzymatic production of cellulases, xylanases, amylases, and laccases were evaluated. Seven different treatments, in which different combinations of wheat straw (WS), wheat bran (WB), orange peels (OP), grapefruit peels (GP), and apple peels (AP) were used, were established. Controls of 2% (w/v) carboxymethyl-cellulose (CMC) and xylan were used in a rich medium for basidiomycetes (RMB). The highest titers were achieved using OP-based cultures, with large titers of CMCases (33.5 U), avicelases (15.7 U), beta-D-glucosidase (72.9U), and xylanases (18.3 U). The best levels of amylase and laccase activity were obtained in the RMB plus CMC (RMB-CMC) (7.2 U) and in the medium OF/AP/GP (6.4 U), respectively. The relative molecular sizes of cellulase, xylanase, and amylase were 66.2, 56.5, and 90.8 kDa, respectively. Laccase and amylase had maximum activities at 60 degrees C whereas cellulase and hemicellulase had maximum activities at 70 degrees C. The optimal pH for cellulases, xylanases, and amylases was 5.0 in every case, and more than 95% activity was observed at pH 6. These results reveal some efficient operating parameters for the application of these enzymatic extracts as adjuvants to improve animal nutrition.