No abstract

In this paper, we reported that oil pam trunk (OPT) can be used as an alternative fermentation feedstock for lignocellulolytic enzyme production and carbon source for bioethanol production. Xylanase production from OPT by locally isolated fungus, Aspergillus fumigatus SK1, under solid state fermentation (SSF) was optimized using central composite design (CCD). Under optimized conditions, a maximum xylanase activity of 1792.43 U/g was produced, which was 4.28 folds higher than before optimization. Significant amount of CMCase (56.19 U/g), FPase (3.47 U/g), and β-glucosidase (1.55 U/g) were also found concomitantly with xylanase. Subsequently, the effect of solid loading, Tween-80 concentration and incubation temperature on saccharification of OPT by the crude enzymes were optimized to enhance the total reducing sugar production. A total of 13.148 g/L of reducing sugar was reported at optimized condition. The comparisons of physiochemical characteristics between native and hydrolysed OPT by SEM, FTIR and XPS showed strong degradation capacity of the crude enzymes towards cellulose, hemicellulose and lignin.Alcoholic fermentation of the hydrolysate by Candida tropicalis RETL-Crl produced 3.067 g/L of ethanol. Higher ethanol production at 0.322 g/g with theoretical ethanol yield of 68.05%indicates Candida tropicalis RETL-Crl has a greater potential to be used in ethanol fermentation process. This result further proved that OPT has potential to be used as a renewable carbon source.