Dados do Trabalho

Título

Biotransformation of soy isoflavones to improve anti-inflammatory potential in intestinal cellular model

Introdução

Soy isoflavones have been widely explored owing to several benefits to human health. Only glycosylated forms are found in high concentrations in soybeans. So, biotransformation processes aiming to increase aglycones and metabolites appear as an alternative to improve the bioactivity of soy-based products. Studies have reported a positive effect of bioactive compounds in the intestinal inflammation. In this context, the present study investigated the role of biotransformed soymilk by enzymatic and fermentative processes in order to modulate the intestinal inflammation using an in vitro cellular model.

Material e Métodos

This work assessed four distinct biotransformation processes using tannase enzyme and probiotic strains. Isoflavones were identified and quantified by HPLC analyses and the antioxidant capacity of soy extracts was determined by DPPH, ORAC, and FRAP tests. The inflammatory assay was carried out using Caco-2 cell model, induced by IL-1β, and the interleukin 8 (IL-8) level was measured by ELISA assay. The ability to reduce the generation of intracellular reactive oxygen species (ROS) was also evaluated using a fluorescent probe.

Resultados e Discussão

The results showed that the enzymatic and fermentative processes were able to bioconvert glycosides into aglycones, reducing the glycosidic forms to undetectable levels. Biotransformation processes involving tannase presented the highest increase in aglycones content (1.61-1.85 and 6.08-7.48 times for daidzein and genistein, respectively) compared to soymilk control. According to ORAC assay, an increase of 87-98% in antioxidant capacity was noted when soymilk was biotransformed by tannase enzyme and probiotic strains. Intracellular ROS reduced by 37% when fermented soymilk was tested at the highest concentration. Anti-inflammatory responses in Caco-2 cells were expressive. A significant decrease in IL-8 secretion was observed for all biotransformed samples, leading to a reduction in cytokine levels between 52-91%, in comparison to cells stimulated with IL-1β. Similar to our findings, other authors reported an increase in aglycone levels after biotransformation of soymilk and inhibition of IL-8 expression by biotransformed extracts with tannase.

Conclusão

Biotransformed soymilk by tannase has a great potential to improve health conditions, defending the intestinal cells from oxidative damage and acting as a possible adjuvant in inflammatory process.