Effect of Yeast Extract on Bioethanol Production from Banana Hydrolysate

Bioethanol is one of the most frequently used biofuels. It is produced by fermenting sugars derived from lignocellulosic biomass and hydrolysing cellulose from that biomass. Yeast extract, a by-product of yeast cells, is widely utilised in bacterial growth mediums as a nutritional resource. However, the role of yeast extract in bioethanol production from banana hydrolysate has not yet been studied. This work investigates the effect of yeast extract on bioethanol production from the banana hydrolysate. It also aimed to identify the optimal yeast extract concentration for bioethanol production from banana hydrolysate. Initially, the banana stem was enzymatically hydrolysed using liquozyme and spirizyme. The resulting hydrolysate was then used as a feedstock for bioethanol fermentation. The medium was supplemented with yeast extract from 2 g/L to 6 g/L. The glucose consumption and bioethanol concentration were analysed using high-performance liquid chromatography. The results showed that fermentation supplementation with 2 g/L yeast extract produced the highest amount of ethanol concentration, which was 4.9-fold over that of control experiment. In general, this work gives useful insight into the production of bioethanol from low cost feedstock