Comparison of SHF and SSF of wet exploded corn stover and loblolly pine using in-house enzymes produced from T. reesei RUT C30 and A. saccharolyticus

Abstract

The aim of the present study was to compare bioethanol production from wet exploded corn stover (WECS) and loblolly pine (WELP) hydrolyzed with in-house and commercial enzymes and fermented separately (SHF) and simultaneously (SSF). In-house enzymes produced from Trichoderma reesei, RUT-C30 and a novel fungal strain, Aspergillus saccharolyticus were loaded as 5 and 15 FPU/g glucan and supplemented with 10 and 30 CBU/g glucan, respectively. For hydrolysis and fermentation, slurries of WECS and WELP at 5 and 10% (w/w) solids loading (SL) were utilized. Saccharomyces cerevisae was used for ethanol fermentation at 33°C. Maximally, 15.6 g/L and 13.4 g/L (corresponding to theoretical ethanol yield of 76% and 67%, respectively) were achieved in SSF process from WECS and WELP, respectively at 5% SL and 15 FPU/g glucan loading of in-house enzymes. Ethanol concentrations in all cases were higher for SSF compared to SHF under same conditions. A cross comparison of SSF with commercial enzymes (Celluclast 1.5 L + Novozym 188) showed highest ethanol concentration of 17.3 g/L and 15.4 g/L (corresponding to theoretical ethanol yield of 84% and 77%, respectively) from WECS and WELP, respectively at 5% SL and 15 FPU/g glucan. These findings demonstrated that in-house enzymes were comparable to commercial enzymes as these fungi produced other lignocellulolytic enzymes beyond cellulase and hence enhanced the overall enzyme activity.

A comparison between SHF and SSSF processes from cardoon for ethanol production

“…The EY % displayed in Table 6 are in accordance with a recent study (Rana et al, 2014) which carried out a comparison between SHF and SSF processes, varying the solid loadings (5-10%) and enzyme dosages (5-15 FPU/g glucan) employing two different raw materials (corn stover and loblolly pine). In all the trials, the SSF process showed higher final ethanol concentrations for both types of feedstock.…”

Utilization of recombinant Trichoderma reesei expressing Aspergillus aculeatus β-glucosidase I (JN11) for a more economical production of ethanol from lignocellulosic biomass

“…Novozyme 188 showed higher hemicellulose-specific (mannanase and xylanase) activities, which also contributed towards its saccharification ability. Our data show that Novozyme 188 is indeed a suitable supplementary enzyme for reinforcing T. reesei cellulase, which remains the traditionally favorable enzyme mixture for lignocellulosic materials degradation (19,31).…”

Enzymatic Conversion of Sugar Beet Pulp: A Comparison of Simultaneous Saccharification and Fermentation and Separate Hydrolysis and Fermentation for Lactic Acid Production

“…The difference between the optimum conditions for enzymatic hydrolysis and those for fermentation could cause problems (39). However, a comparison of SHF and SSF conducted by Rana et al (40) found that SSF was more efficient than SHF, despite using a lower reaction temperature, which is suboptimal for enzyme hydrolysis. The lower temperatures and shorter operating times required for SSF processes result in energy savings, which are a significant advantage of the system (16,41).…”