title: Effects of fermentation on antioxidant properties and phytochemical composition of soy germ.
abstract: BACKGROUND
  Traditional soy-fermented foods, such as miso, douche, natto, and tempeh have been widely used as a dietary supplement in Asian countries, and numerous reports on their phenolics and antioxidant activities have been published. Soy germ contains 10-fold higher phenolics than whole soybean, hence using soy germ as fermentation substrate will be more efficient than whole soybean.
  
  
  RESULTS
  Soy germ fermented with Aspergillus niger M46 resulted in a high-efficiency bio-transformation of phenolics and flavonoids to their metabolites, and a diverse secondary metabolic product was also found to response oxidation stress of fungal colonisation. Its antioxidant activity against hydroxyl radicals and superoxide radicals (IC50 = 0.8 and 6.15 µg mL(-1) , respectively) was about 205-fold and 47-fold higher than those of unfermented soy germ (IC50 = 164.0 and 290.48 µg mL(-1) ), respectively. These results were similar to those observed for Trolox, and more active than those of BHT and hesperidin. The β-glucosidase and α-amylase produced during fermentation were mainly responsible for mobilisation of the phenolics.
  
  
  CONCLUSIONS
  Our results demonstrate that fermented soy germ has the potential to be a good dietary supplement for prevention of oxidative stress-related diseases, and the solid-state bioprocessing strategy could be an innovative approach to enhance the antioxidant activity of soy germ.
authors.affiliation: Department of Food and Beverage Management, Ta Hwa University of Science and Technology, No. 1 Dahua Rd, Qionglin Shiang, Hsinchu County, 307, Taiwan, Republic of China.
authors.forename: I-Chuan
authors.initials: IC
authors.lastname: Sheih
authors.forename: Tony J
authors.initials: TJ
authors.lastname: Fang
authors.forename: Tung-Kung
authors.initials: TK
authors.lastname: Wu
authors.forename: Ru-Yin
authors.initials: RY
authors.lastname: Chen
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D001234:Aspergillus niger / Q000378:metabolism; D005285:Fermentation; D005419:Flavonoids / Q000032:analysis*; D005511:Food Handling / Q000379:methods; D018384:Oxidative Stress; D010636:Phenols / Q000032:analysis; D059808:Polyphenols / Q000032:analysis*; D012639:Seeds / Q000737:chemistry*; D013025:Glycine max / Q000737:chemistry*; D000516:alpha-Amylases / Q000378:metabolism; D001617:beta-Glucosidase / Q000378:metabolism
chemical_list: D000975:Antioxidants; D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols; D000516:alpha-Amylases; D001617:beta-Glucosidase
keywords: Aspergillus; antioxidant; fermented soy germ; phenolics