Comparative Studies of Bioethanol Produced from Cassava Peel Using Aspergillus niger and Saccharomyces cerevisiae in Submerged Fermentation

Background: Cassava peel is one of the largest agricultural wastes in Nigeria, and it is generated by processing cassava tubers for human and industrial use. This project study compared the bioethanol produced from cassava peel using Saccharomyces cerevisiae ATCC 204508/S288c and Aspergillus niger isolated from onion bulbs. Methods: Proximate analysis was done on the peels using standard methods of analyses of the Associ-ation of Official Analytical Chemists (AOAC). Fermentation for bioethanol production was done for 6 days using submerged fermentation. Parameters such as ethanol yield, substrate concentration and pH were optimised for bioethanol production. The pH was determined using standard techniques. Ethanol yield was measured via spectrophotometer and ethanol standard curve techniques. Results: Proximate composition showed the following: moisture (9.75± 0.55 %), crude ash (3.12± 0.25 %), crude fibre (9.50± 0.01 %), crude fat (1.50±0.05 %), protein (2.54± 0.06 %), carbohydrate (73.50 ± 0.05 %). pH ranged from 4.50±0.25 to 3.20±0.30 for S. cerevisiae, and A. niger ranged from 4.50±0.30 to 3.20±0.04. Ethanol yield for S. cerevisiae ranged from 18.50±0.05b to 28.03±0.45a with a concen-tration of 30 g/ml having the highest at Day 4 and 30 g/ml having the lowest at Day 1 and A. niger ranging from 17.00±0.50b to 27.54±0.05b with concentration 30 g/ml having the highest at Day 4 and 10 g/ml having the lowest at Day 1. Conclusion: This research, therefore, indicates that cassava peel could serve as a cheap and promising substrate for bioethanol production using S. cerevisiae and A. niger.