Abstract:

The production process of acidic phytase based on the use of wheat bran as fermentation substrate in solid-state fermentation by Aspergillus niger TW012 was optimized using single factor method and orthogonal array design in this study. The optimum fermentation conditions were found to be: ammonium sulfate content in medium 1.6%, medium initial pH 5.0, medium water content 70%, fermentation temperature 30 ℃, and fermentation cycle 5 days. Under these optimum conditions, the maximum acidic phytase activity in the final fermentation product reached up to 346.576 U/g dry matter, 23.77% higher than before optimization.

Key words: acidic phytase, solid-state fermentation, technology, orthogonal array design