Production of Bio-Ethanol from Selected Agro Waste Using Saccharomyces cerevisiae and Lactobacillus delbrueckii

Abstract

The increasing generation of agricultural waste and the need for alternative renewable energy sources have encouraged the utilisation of agro-wastes for bioethanol production. This study investigated bioethanol production from cassava peel, banana peel, and their mixture using Saccharomyces cerevisiae and Lactobacillus delbrueckii. The agro-wastes were washed, dried, milled, hydrolysed, fermented, and distilled. The microorganisms were identified using cultural, microscopic, biochemical, and molecular techniques. Ethanol yield was determined after fermentation and distillation, while the data were analysed using one-way analysis of variance and Duncan’s multiple range test at p ≤ .05. Raw banana peel recorded the highest reducing-sugar content (37.82 ± 0.68%), while raw cassava peel recorded 14.57 ± 1.03%. The combined culture of S. cerevisiae and L. delbrueckii produced the highest ethanol yields of 13.21%, 20.86%, and 21.94% at 20, 30, and 40 g substrate concentrations, respectively. Fermentation organism significantly affected ethanol yield at all substrate concentrations (p < 0.001). The average ethanol yield was 13.83% for the banana and cassava mixture, 12.26% for cassava peel, and 6.80% for banana peel. The findings demonstrate that cassava and banana peels are suitable substrates for bioethanol production, with the combined microbial culture producing higher yields under the conditions investigated.