Mahula (Madhuca latifolia L.) flower is a suitable alternative cheaper carbohydrate source for production
of bio-ethanol. Recent production of bio-ethanol by microbial fermentation as an alternative energy
source has renewed research interest because of the increase in the fuel price. Saccharomyces cerevisiae
(yeast) and Zymomonas mobilis (bacteria) are two most widely used microorganisms for ethanol production.
In this study, experiments were carried out to compare the potential of the yeast S. cerevisiae (CTCRI
strain) with the bacterium Z. mobilis (MTCC 92) for ethanol fermentation from mahula flowers. The ethanol
production after 96 h fermentation was 149 and 122.9 g kg_1 flowers using free cells of S. cerevisiae
and Z. mobilis, respectively. The S. cerevisiae strain showed 21.2% more final ethanol production in comparison
to Z. mobilis. Ethanol yield (Yx/s), volumetric product productivity (Qp), sugar to ethanol conversion
rate (%) and microbial biomass concentration (X) obtained by S. cerevisiae were found to be 5.2%,
21.1%, 5.27% and 134% higher than Z. mobilis, respectively after 96 h of fermentation.