Blending of cellulolytic enzyme preparations from different fungal sources for improved cellulose hydrolysis by increasing synergism

Abstract

Cellulolytic enzymes were produced from the three fungal strains [P. janthinellum EMS-UV-8 (E), T. reesei Rut C-30 (R) and A. tubingenesis (A)] and used to prepare blends for the hydrolysis of avicel and acid treated wheat straw (A-WS). An enzyme blend prepared from three different crude preparations (E + R + A) on the basis of equivalent FPU or protein was found to be more synergistic and gave better hydrolysis of avicel or A-WS than the blend of two enzyme preparations (E + R, E + A and R + A) or individual enzyme preparations (E, R, and A). The triple blend gave two times higher hydrolysis of avicel or A-WS than the individual enzyme preparations at the same enzyme dosages. In all cases the individual or cumulative FPU or protein in blends was equal (10 FPU or 20 mg protein per g of substrate). Increased enzyme activities (CMCase and FPU) were found in the blends compared to the sum of individual enzyme activities added for the blend preparation. This reveals that the increased hydrolysis of cellulose by blends was a result of increased synergism between the same (endoglucanase) and/or different types of cellulases from different preparations. Enzyme blending is thus a facile, cost effective and sustainable approach for biomass saccharification for biofuels.