Osmotolerance and Fermentative Pattern of Brewer’s Yeast

ENGLISH/ANGLAIS] Affiliations: 1Department of Biological Sciences, Microbiology unit, Fountain University, Osogbo, Osun State, NIGERIA 2Department of Microbiology, Ahmadu Bello University, Zaria, Kaduna State,NIGERIA * Email Address for Correspondence/ Adresse de courriel pour la correspondance: [email protected] Accepted/Accepté: February, 2012 Full Citation: Jimoh SO, Ado SA, Ameh JB, Whong CMZ. Osmotolerance and Fermentative Pattern of Brewer’s Yeast World Journal of Life Sciences and Medical Research 2012;2(2):59-64. Yeast strains isolated from locally brewed beverages which comprised of different species were tested for physiological characteristics such as fermentative ability, growth on 50% /v glucose, nitrate assimilation and osmotolerance capacity using industrial strain as standard. Among the Saccharomyces cerevisiae and nonsaccharomyces strains analysed, 83.93% were highly osmotolerant while 16.07% were moderately osmotolerant compared with the standard strain which was also moderately osmotolerant. All yeast strains fermented glucose and sucrose while none fermented lactose. Furthermore, both S. cerevisiae and nonsaccharomyces strains grew on 50% glucose while only the non-saccharomyces strain assimilated nitrate. This implies that, yeasts are highly tolerant to osmotic shock and there is variation in their ability to assimilate nutrients.