Several studies were carried out on phytase activityfrom baker’s yeast (Saccharomyces cerevisiae) duringleavening of bread dough (Harland and Harland 1980;Harland and Frolich 1989; Turk et al. 1996, 2000; Andlidet al. 2004). Phytase from baker’s yeast was first extractedby Nayini and Markakis (1984) and they found an opti-mum pH to be 4Æ6 and optimum temperature of 45C.On the other hand, In et al. (2009) found optimum pHfor S. cerevisiae phytase to be 3Æ6at40C and this is inaccordance with Turk et al. (1996) who found a similaroptimum pH of 3Æ5at30C. Hellstrom et al. (2010) iso-lated nine yeast species from Tanzania togwa and showedthat Issatchenkia orientalis (anamorph Candida krusei)and Hanseniaspora guilliermondii completely degraded allIP6 in YPD medium, supplemented with 5 mmol l)1IP6,within 24 h of fermentation at 30C and pH 6Æ5. Duringthe first 3 h of fermentation, only marginal amount ofIP6 was degraded. This is in agreement with the resultsobtained by Turk et al. (2000) from fermentations withbaker’s yeast in synthetic medium supplemented with0Æ88 mg ml)1IP6 at 30C and pH 5Æ3 (conditionsrelevant for leavening of bread dough).