Improvement of Bioethanol Production using Amylasic Properties from Bacillus licheniformis and Yeasts Strains Fermentation for Biomass Valorization

Abstract

Saccharomyces is a potentially useful organism for the commercial production of ethanol as it is not capable of fermenting starch containing in the mango peel. To enhance this carbon source utilization and increase the rate of alcohol production, simultaneous saccharification and fermentation were conducted using Bacillus licheniformis and yeasts. The proposal of this research was to study amylasic activity, rate and amount of starch utilization and ethanol yields increasing several-fold in coculture due to the synergistic metabolic interactions between the species. The methods used, included: enzymatic hydrolysis with B. licheniformis and simultaneous saccharification and fermentation with S3 and A1. These two yeasts strains were isolated from wine and among local beer yeasts respectively. The enzymatic hydrolysis has allowed to obtain 78% (g g -1) of reducers sugars released. The maximum concentration of ethanol produced from peel mango by S3 and A1 during 5 days were, respectively 16 and 14.4 g L -1.