Journal of Pure and Applied MicrobiologyVol. 2 No. 1

Effect of Some Composed Media and Mutation on the Growth, Sucrose-degrading-enzyme and Leavening Activities of Candida versatalis Strain ‘Bol 1’

B. Boboye* and Y. Oigiangbe

Department of Microbiology, Federal University of Technology, P. M. B. 704, Akure, Ondo State (Nigeria)

Received on February 08, 2008 and accepted on March 12, 2008

 

ABSTRACT

Some media were composed namely: cassava-groundnut extract (CGE), maize-groundnut extract (MGE), sweet potato-groundnut extract (SPGE), soybean extract (SBE) and sucrose-locust bean extract (SLBE). Effect of these media on the growth of Candida versatalis strain ‘Bol 1’ was determined. The fungus was mutated chemically with hydroxylamine. The wild-type strain and the mutants were tested for their ability to synthesize sucrose-degrading-enzyme when grown in nutrient broth (NB) and sucrose-minimal-medium (SMM). They were assessed for leavening property in bread making relative to a commercial (instant) baker’s yeast. The yeast grew best in MGE with optical density of 1.85 at 670 nm followed by SBE, SLBE, SPGE and CGE in decreasing order of cell density. The rate at which the mutation occurred was 2.2% survived cells. The mutants and wild yeast showed varying levels of sucrose-degrading-enzyme activity. Some mutants synthesized the enzyme in both NB and SMM. The baker’s yeast leavened the bread dough best followed by the wild-type strain and mutant numbers 50 and 20.

Keywords : Composed media and Mutation effects, Candida versatalis strain ‘Bol 1’.