Enhancement of the antioxidant capacity of soymilk by fermentation with Lactobacillus rhamnosus

MARAZZA, J. A.; NAZARENO M.A.; SAVOY DE GIORI G.; GARRO M.S.

Journal of Functional Foods

Elsevier

Lugar: Oxford; Año: 2012 vol. 4 p. 594 - 601

1756-4646

In order to enhance the bioactivity of soy beverages, fermentation of soymilk was assayedusing Lactobacillus rhamnosus CRL981 as a b-glucosidase producer. The biological activity ofthe fermented soy beverage enriched in isoflavone aglycones was determined by severalmethods to evaluate different antioxidant mechanisms. Fermented soymilk exhibitedhigher antioxidant activity (71.2 ± 4.0%) determined by b-carotene bleaching method butlower, although significant, DPPH radical scavenging effect (29.5 ± 0.9%) than the unfermentedsoymilk used as control. The fermented soymilk extracts were able to inhibit theoxidation of DNA induced by Fenton?s reagent. The increase of isoflavone aglycone contentsduring fermentation was a result of b-glucosidase activity towards isoflavone glucosides.This process allowed obtaining a soy beverage with enhanced antioxidant capacityable to contribute to the health and nutritional status improvement of consumers.