The aim of this work is to study the application of molasses and whey permeate as potential sources of carbon for ethanol production. Also, to study the elimination of agro-industrial wastes and consequently, decrease the cost of ethanol production. Sugar cane molasses and whey permeate were used as carbon sources for ethanol production by yeasts and bacterial strains. Different concentrations of sugar (10, 15, 20 and 25%) were used to study fermentation by two yeast strains (Kluyveromyces marxianus NRRL85.54 and Saccharomyces cerevisiae O-14) and one bacterial strain ( Zymomonas mobilis ATCC 10988). Also, Ethanol production was examined by mixture of molasses and whey permeate using these strains and their mixed culture.bResults clearly indicated that the optimal sugar concentration was 10% sugar for high efficiency of ethanol fermentation by Kluyveromyces marxianus NRRL85.54, Saccharomyces cerevisiae O-14 and Zymomonas mobilis ATCC 10988. Results also showed that best agro-industrial waste for ethanol production is whey permeate with K.marixuanus followed by the mixture of molasses and whey permeate (10% sugar concentration) with mixed culture of three strains then molasses with K.marixuanus.
