Optimization of Cellulase Production by Pycnoporus sanguineus in 5 L Stirred Tank Bioreactor and Enhanced Fermentation by Employing External Loop

Abstract

Palm oil mill effluent (POME) and oil palm frond (OPF) could be used as an adequate source of cellulose for the production of cellulolytic enzyme. Batch culture of Pycnoporus sanguineus in conventional stirred tank bioreactor (CSTB) showed that biomass and cellulase production were influenced by POME concentration, aeration rate, and agitation speed. Optimization with central composite design (CCD) indicated an optimum condition at 70% (v/v) POME concentration, 350 rpm agitation speed and 1.0 vvm aeration rate with maximum enzyme activities at 16.073, 10.012, 2.348 and 12.186 IU/ml for CMCase, FPase, BG, and laccase, respectively. These optimized parameters were then adapted in the studies using stirred tank bioreactor with external loop (STBEL), in which OPF served as a supporting matrix. Enzyme productions were shown to improve with higher maximum biomass (52.75 g/L) and enzyme activities (CMCase 18.221 IU/mL, FPase 13.406 IU/mL, BG 3.370 IU/mL, and laccase, 17.481 IU/mL) compared to CSTB.