Production of Bioethanol from Banana Peel Using Isolated Cellulase from Aspergillus Niger

Abstract

In the present work, banana peel, being one of the least investigated biomasses in India, was utilized for the production of bioethanol. Dried and ground banana peel was subjected to ultrasonication at an operating frequency of 20 kHz and 750 W with 2% (v/v) sulphuric acid for 1 h. After the pretreatment, the lignin reduction was 67.50% and the hemicellulose and cellulose recoveries were 45.6 and 69.3%, respectively. Aspergillus niger which is capable of producing cellulase enzyme was utilized for the hydrolysis of pretreated banana peel. The activity of isolated crude cellulase enzyme was estimated as 1.712 FPU/ml. The pretreated banana peel was hydrolysed at 50 °C, and the effect of enzyme loading [10–50 FPU] and incubation time [24–96 h] on reducing sugar was determined. Hydrolysate was fermented using 24 h activated Saccharomyces cerevisiae, and the effect of fermentation time from 18 to 120 h was investigated. Ethanol concentration was maximum at 24th h of fermentation, and it was 4.24 g/l. The high recovery of cellulose via ultrasonication makes the banana peel suitable for bioethanol production. By providing the in vitro produced enzymes, the usage of commercial enzymes can be eliminated and hence the cost of production of bioethanol might be reduced.