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Fermentative
production and application of acid phytase by
Saccharomyces cerevisiae CY strain
Man-Jin In1, Sung-Won Seo2
and Nam-Soon Oh2*
1Department
of Human Nutrition and Food Science, Chungwoon University,
Hongseong 350-701, South Korea.
2Department
of Food Science and Technology, Kongju National University,
Yesan 340-802, South Korea.
*Corresponding author. E-mail:
nsoh@kongju.ac.kr.
Tel: +82-41-330-1485. Fax: +82-41-333-9610.
Accepted 16 July, 2008 |
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Improvement of phytase production from
Saccharomyces cerevisiae CY strain was attempted by
optimizing the culture medium. The optimum medium components
for cell growth and enzyme production were found to be
galactose, ammonium sulfate, sodium phytate, and magnesium
sulfate. Galactose (5%) and ammonium sulfate (2%) were the
most suitable carbon and nitrogen sources, respectively, for
phytase production. The phytase activity was most active at
pH 4.0 in the initial medium conditions. Phytate stimulated
enzyme production at low concentration; however, phytase
activities were decreased with increase of phytate
concentration at above 0.002%. Maximum phytase activity was
135.09 mU/mg DCW after 72 h fermentation under optimal
conditions. The harvested S. cerevisiae CY cells were
used for the degradation of phytate in the soybean-curd
whey. Over 60% of phytate in the soybean-curd whey were
nearly linearly degraded with cells of 27.16 U/g-phytate
dosage as phytase source after a hydrolysis time of 2 h.
Key words:
Culture medium, fermentation, phytase, phytate degradation,
Saccharomyces cerevisiae. |
