Biological pretreatment of empty fruit bunch (EFB) using oleaginous Aspergillus tubingensis TSIP9

Abstract

Empty fruit bunch (EFB) is one of lignocellulosic wastes from palm oil mill. They are attractive feedstocks for production of fermentable sugars due to their low cost, renewable nature and abundance. Biological pretreatments employ microorganisms mainly fungi to reduce lignin and increase cellulose content prior to hydrolysis of cellulose into fermentable sugars. In this study, oleaginous fungi Aspergillus tubingensis TSIP9 with cellulolytic enzymes was used as potent microorganism for biological pretreatment of EFB through solid state fermentation (SoSF). The effluent from anaerobic digester (biogas effluent) was used as nutrient sources and moisturizing agents. After optimization in SoSF bioreactor, the cellulose content in EFB was increased from 40.58 ± 0.99% up to 61.24 ± 0.05% and this process also produced lipids of 115.8 ± 3.24 mg/g-EFB and cellulolytic enzymes of 20.00 ± 1.11 U/g-EFB. This study has shown that it was possible to biorefinery palm oil mill wastes into valuable cellulose pulp, microbial lipids and enzymes with the low-cost, practical and environmental friendly process.