Penicillium fermentation combined with enzyme treatment to enhance the release of phenolic acids from wheat bran

Abstract

Phenols from wheat bran play an important role in improving the physiological function of human body because of their potential antioxidant capacity. However, most of the phenols in wheat bran exist in the form of insoluble binding, which limits their application in the field of food and medicine. In this paper, the modification of wheat bran by Penicillium solid-state fermentation (SSF) was studied. It was found that the content of free phenolic acids in wheat bran was significantly correlated with the activity of key hydrolytic enzymes in the fermentation process. On the fifth day of Penicillium fermentation, the content of free phenolic acids was the highest, which was 750.98 μg/g, which was 1.78 times higher than that of the control. The release of free phenolic acids was highest when wheat bran was treated with compound enzyme at 300 U/mL. Furthermore, the structure of wheat bran was significantly changed by fermentation with enzyme addition. On the 5th day of fermentation, the content of free phenolic acids was as high as 1500 μg/g, which was twice as much as that of fermented bran and 3.56 times that of unfermented bran.