Enrichment of phenolics and free radical scavenging property of wheat koji prepared with two filamentous fungi.
In the present study, total phenolic content and antioxidant property of wheat (54% ethanolic extract) was drastically enhanced when fermented with two GRAS filamentous fungi, Aspergillus oryzae and Aspergillus awamori nakazawa. A. oryzae yielded significant (P<0.05) amounts of phenolic compounds, DPPH* (2,2-diphenyl-1-picrylhydrazyl) and ABTS*(+) [2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid)] scavenging properties on 4th day of incubation compared to A. awamori on 5th day of incubation. A linear correlation was observed between total phenolic contents and activities of three different carbohydrate hydrolyzing enzymes (alpha-amylase, beta-Glucosidase and xylanase) produced by A. oryzae. However, in case of A. awamori nakazawa, only two enzymes (xylanase and beta-glucosidase) were mainly responsible for the release of phenolics. This study demonstrated that fermented wheat grain is a better source of phytochemicals compared to non-fermented wheat. In addition, different carbohydrate cleaving enzymes are responsible for the improvement of phytochemical properties of fermented wheat.
Bhanja
Tapati
T
Microbial Biotechnology and Downstream Processing Lab, Agricultural and Food Engineering Department, Indian Institute of Technology, Kharagpur, West Bengal 721 302, India.
Kumari
Anjali
A
Banerjee
Rintu
R
D001230:Aspergillus / Q000145:classification / Q000378:metabolism*; D018920:Coculture Techniques; D005516:Food Microbiology; D005527:Food, Fortified / Q000032:analysis / Q000382:microbiology*; D016166:Free Radical Scavengers / Q000737:chemistry*; D005609:Free Radicals / Q000737:chemistry*; D010636:Phenols / Q000737:chemistry*; D013045:Species Specificity; D014908:Triticum / Q000737:chemistry* / Q000382:microbiology*
D016166:Free Radical Scavengers; D005609:Free Radicals; D010636:Phenols