Abstract
Isoflavone aglycone-rich soymilk fermented by Lactobacillus delbrueckii subsp. delbrueckii, strain TUA-4408L (F4408) has stronger lipid metabolism-modulating effects than isoflavone aglycone-poor soymilk fermented by Lactobacillus delbrueckii subsp. delbrueckii, strain TUA-4404L (F4404). As such, fermentation products other than isoflavone aglycones may also exert lipid metabolism-modulating effects. Therefore, the present study aimed to compare the metabolites in soymilk (SM), F4404, and F4408 via a metabolomics approach. Various aglycones including isoflavones, flavones, flavonols, and flavanones increased in both F4404 and F4408 compared with SM. The increases in isoflavone and flavanone aglycones were greater in F4408 than in F4404. Some types of dipeptides and free amino acids, especially ornithine, increased in both fermented soymilks. The increase in free amino acids, especially ornithine, was higher in F4408 than in F4404. Thus, F4408 exhibited stronger glycosidase and protease activities than F4404. Functional components produced by lactic acid fermentation are known to improve lipid metabolism. Therefore, it is suggested that not only isoflavone aglycones but also other functional components exert lipid metabolism-modulating effects in fermented soymilks, especially soymilk fermented using TUA-4408L.
Highlights
Traditional soy foods produced in Asia are known to have lipid metabolism-modulating effects [1]
The increases in isoflavone and flavanone aglycones were greater in F4408 than in F4404
In our previous study, when we compared the physiological effects of fermented soymilk containing a high ratio of isoflavone aglycone with those of fermented soymilk containing a low ratio of isoflavone aglycone, we found that an increase in isoflavone aglycones in fermented soymilk enhanced its lipid metabolism-modulating effect [21], suggesting that fermentation products other than isoflavone aglycone may be responsible for these effects
Summary
Traditional soy foods produced in Asia are known to have lipid metabolism-modulating effects [1]. Clinical analyses and meta-analyses have demonstrated the lipid metabolism-modulating effects of combined isoflavones and soy protein [11] [12] [13] [14]. Lactic acid fermentation converts the isoflavone glycosides in soymilk to isoflavone aglycones [15], enhancing their absorption in the intestine [16]. We previously reported the lipid metabolism-modulating effects of fermented soymilk in rats fed an AIN-93G diet [17], a high-cholesterol diet [18], a high-fat diet [19], and a high-fat and high-cholesterol diet [20] [21]. Our results indicated that an increase in the amount of isoflavone aglycones in fermented soymilk enhanced its lipid metabolism-modulating effects [21]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
