Amal W. Abou El- Khair, Khadiga I.M. El-Gabry and Sanaa S.H. Sarabana( 2014). Screening of Fungal Candidates for Ethanol Production from Agro-Industrial WastesMiddle East Journal of Applied Sciences, 4(4): 1141-1149, 2014 ISSN: 2077-4613
Abstract: Some samples were collected from different rotten agricultural wastes, decomposed wood and compost, to screen different isolates of fungi for their ability to produce ethanol. The main goal of this research was to obtain isolates capable of fermentation of agro-industrial wastes i.e. vinasse and whey permeate. One hundred and seven isolates were secured on potato dextrose agar medium. Twenty eight isolates were positive for ethanol production; among those four were the most efficient ethanol producers. They were identified morphologically and biochemically as Fusarium oxysporum-I, Mucor indicus, Aspergillus versicolor-2 and Aspergillus oryzae. They were compared with Fusarium oxysporum known with its ability to produce ethanol. Upon studying the time course for ethanol production by these five fungi, the 5th day was the best time for high productivity. M. indicus was the superior in its efficiency (70.20%), followed by F. oxysporum (53.99%) from the theoretical yields. The effect of different concentrations of glucose (5, 10, 15, 20 and 25%) on ethanol production was also studied. The best concentration for high productivity was 15% by all the tested strains. The efficiency of M. indicus was the highest (66.34% from the theoretical yields) followed by F. oxysporum (52.91%) and A. oryzae (52.84%). The tested fungal strains were compared with Saccharomyces cerevisiae and Kluyveromyces fragilis for ethanol production from vinasse and whey, respectively, as sole carbon source. Because fungi can utilize another organic carbon such as phenolic compounds and glycerol, it was found that these strains were unique for ethanol production from vinasse. F. oxysporum-I was the best producer (1.93 g eth/100 ml) followed by M. indicus (1.89 g eth/100 ml). On glucose, M. indicus was the best, with an efficiency
of 56.38 % from the theoretical yield. In respect to whey; the efficiency of A. oryzae was the highest among all the fungal strains (5.89% from the theoretical yield). But Kluyveromyces fragilis was found to be the most efficient in ethanol production after 24 hrs from whey.
Keywords: (Ethanol production, Fusarium sp., Mucor sp., Aspergillus sp., Saccharomyces cerevisiae, vinasse, whey, Kluyveromyces fragilis.)
