Isoflavone metabolism by a collection of lactic acid bacteria and bifidobacteria with biotechnological interest

Abstract

Almost all soy isoflavones exist as glycosides, daidzin, genistin, and glycitin. We analyzed the capacity of 92 strains of lactic acid bacteria (LAB) and bifidobacteria with biotechnological interest to process the glycosylated isoflavones daidzin, genistin, and glycitin in their more bioavailable aglycones and their metabolites as dihydrodaidzein (DHD), O-desmethylangolensin, and equol. Representative strains of the four genera studied Lactobacillus, Enterococcus, Lactococcus, and Bifidobacterium were able to produce daidzein, genistein, and glycitein, with the exception of the lactobacilli, which did not produced glycitein in soy extracts. The production of the aglycone isoflavones could be correlated with the β-glucosidase activity of the strains. The isoflavone metabolism is limited to the glycoside hydrolysis in the most of these strains. Moreover, Enterococcus faecalis INIA P333 and Lactobacillus rhamnosus INIA P540 were able to transform daidzein in DHD. LAB and bifidobacteria studied in the present work have a great potential in the metabolism of isoflavones and could be selected for the development of functional fermented soy foods.

Biotransformation processes in soymilk isoflavones to enhance anti‐inflammatory potential in intestinal cellular model

“…Gaya et al () investigated the biotransformation of soy extracts and verified that isoflavones metabolism is limited to hydrolysis of glycosidic forms by most of probiotic strains. The authors reported that bifidobacteria and lactic acid bacteria, such as Lactobacillus , have more affinity for conversion of genistin into genistein.…”

“…Biotransformation of glycoside isoflavones into aglycone forms is relevant since aglycones are compounds with more bioactivity, directly associated with higher bioavailability. Besides that, aglycones can generate metabolites, such as O ‐desmethylangolensin and equol (Gaya et al, ; Selma et al, ; Setchell et al, ). In the present work, equol metabolite was not identified.…”

“…These results suggest that fermentative process with probiotic strains was able to convert glycosides and other substrates present in soy extract into aglycones, probably due to the β-glycosidase activity of microorganisms during fermentation (Dueñas et al, 2012). Gaya et al (2016) investigated the biotransformation of soy extracts and verified that isoflavones metabolism is limited to hydrolysis of glycosidic forms by most of probiotic strains. The authors reported that bifidobacteria and lactic acid bacteria, such as Lactobacillus, have more affinity for conversion of genistin into genistein.…”

“…Soybeans and derivatives are considered a great source of phenolic compounds. Isoflavones are found in elevated amounts in these seeds and have been associated with beneficial health effects (Gaya, Peirotén, Medina, & Landete, ; Shao et al, ). However, the bioactive chemical forms of isoflavones, such as aglycones and metabolites, are available in low content or absent in soybeans (Izumi et al, ).…”

Impact of fructose and fructooligosaccharides supplementation upon the fermentation of hydrolyzed okara and its impact upon bioactive components

“…In a previous study, Ruiz-Larrea et al (30) reported that genistein presented a highest antioxidant activity comparing to other isoflavones (daidzein, daidzin and genistin) utilizing ABTS method. Fur-thermore, several attempts have been made to improve bioavailability of isoflavone aglycones from isoflavone glycosides in soya beverage milk by fermentation with lactobacilli and bifidobacteria species and large differences in the deglycosylation ability of these bacteria have been reported by several author (5,8,28,31,32). The microorganisms used in the current work can synthesize β-glycosidase which is responsible for removing the sugar moiety from glycosylated isoflavones (5,9,18).…”