초록
<P>Response surface methodology (RSM) was used to optimize the cultivation conditions for the production of phytase by recombinant <I>Escherichia coli</I> DH5α. The optimum predicted cultivation conditions for phytase production were at 3 hours seed age, a 2.5% inoculum level, an L-arabinose concentration of 0.20%, a cell concentration of 0.3 (as measured at 600 nm) and 17 hours post-induction time with a predicted phytase activity of 4194.45 U/mL. The model was validated and the results showed no significant difference between the experimental and the predicted phytase activity (<I>P</I> = 0.305). Under optimum cultivation conditions, the phytase activity of the recombinant <I>E. coli</I> DH5α was 364 times higher compared to the phytase activity of the wild-type producer, <I>Enterobacter sakazakii</I> ASUIA279. Hence, optimization of the cultivation conditions using RSM positively increased phytase production from recombinant <I>E. coli</I> DH5α.</P>