Optimization of Saccharomyces cerevisiae sp. Strain by1.1b Culture Conditions for Efficient Biosynthesis of D-(-)-mandelate Dehydrogenase

Abstract:

The culture conditions of Saccharomyces cerevisiae sp. strain by 1.1b were optimized for the production of D-(-)-mandelate dehydrogenase which is useful for the asymmetric bioreduction of benzoylformate to form D-(-)-mandelate. The optimum medium (per liter)consistes of 60 g peptone, 30 g maltose, 0.5 g MgSO4, 0.01 g ZnSO4, 1.0 g KCl. After optimization of the culture medium, the enzyme production in shake flasks is enhanced from 2.56 to 20.21 U/L. The optimum fermentation conditions were determined as follows: medium volume 100 mL (i.e., 40% for a 250-mL shake flask), pH 6.5, inoculum size 10 %, temperature 30 ℃, and cultivation time 25 h.