Journal of Biotechnology & Biomaterials
Open Access

Abstract

DThis study was aimed to investigate the feasibility of bio- ethanol production by batch fermentation of kareish cheese whey. Two forms of whey; untreated (crude) whey containing 5% lactose and treated whey (deproteinized and concentrated to 14% lactose) were utilized. Fermentation processes were performed by two strains of Kluyveromyces marxianus and four strains of Saccharomyces cerevisiae which were previously recognized in our laboratory as highly ethanol- producing strains. Effects of different initial pH values, as well as, external supplementation of treated whey by four different nitrogen sources on the rate of ethanol production by the highest two producing strains were also investigated. All the studied yeast strains were able to grow and produce ethanol from both crude and treated whey. Levels of ethanol production ranged between 3.4- 18.5g/l and 24.11-57.66 g/l from crude and treated whey, respectively. The most suitable initial pH maximizing ethanol yield was 5.5 and the best added nitrogen source was yeast extract. Maximum ethanol levels produced by K. marxianus ZMS3GU133329 and S.cerevisia e EC1118 from treated whey adjusted to pH 5.5 and supplemented by 3% yeast extract reached to 69.85 and 65.36 g/L, corresponding to 97.8 and 91.4% of the theoretical values, respectively. The kinetic parameters and productivity were calculated and discussed for all experiments.

Biography

Zohri A A is a Professor of Microbiology at Botany & Microbiology Department, Faculty of Science, Assiut University, Assiut, Egypt. He is the Director of Center of Scientific Consultations & Services (CSCS), Faculty of Science, Assiut University, Assiut, Egypt (2011 until now). His research fields are in taxonomy &physiology offungi, mycotoxins, pollution, control of mycobiota and mycotoxins in foods & feeds as well as biotechnology for bio-production of ethanol, organic acids, antibiotics, therapeutics and other valuable compounds using microorganisms. He also served as Supervisor of Industrial Fermentation Section, Sugar Technology Research Institute, Assiut University, Assiut, Egypt (2007-2013). He has published more than 80 scientific papers in all my research fields published in different national and international journals and attended more than 50 scientific conferences, symposiums and workshops in the research interests in Egypt, Saudi Arabia, Germany, Italy and France.