Optimization of carbon and nitrogen sources for phytase production by Mitsuokella jalaludinii, a new rumen bacterial species

摘要

Aims: The effects of different carbon and nitrogen sources on phytase production by Mitsuokella jalaludinii were evaluated and the optimization of rice bran (RB) and soybean milk (SM) concentrations in the medium for phytase production was also determined. Methods and Results: Replacement of glucose, cellobiose and starch in MFi medium by RB or palm kernel cake and replacement of trypticase peptone and yeast extract in the medium by SM or enzymatic digested soybean milk significantly increased the phytase production by M. jalaludinii. The optimal concentrations of RB and SM in the medium for phytase production were 15% RB and 20% SM or 20% RB and 10% SM or 20% RB and 20% SM and the phytase activities in the media were 12-53, 12-93 and 12-75 U g~(-1) culture broth, respectively. Conclusions, Significance and Impact of the Study: The high production of phytase by M. jalaludinii warrants further research to increase its yield by genetic manipulation for commercial application.