RESUMO
The peel of the red-jambo concentrates the majority of the bioactive compounds and antioxidant capacity of the fruit. Minor phenolic compounds in this part of the fruit are still unknown, as well as the effect of its extracts in in vitro and in vivo studies. In an ethanolic extract of red-jambo, a wider range of phenolic compounds was investigated and the antioxidant cellular antioxidant activity and inhibition of HepG2 cell proliferation were evaluated for the first time. Using HPLC-FLD/DAD for phenolic compounds determination, gallic acid, chlorogenic acid and (-)-epigallocatechin gallate were found for the first time in the peel of the red-jambo fruit. The anthocyanins found (cyanidin 3,5-diglucoside, cyanidin 3-glucoside and peonidin 3-glucoside) were the flavonoid class strongly correlated with the antioxidant capacity methods used in this study (cellular antioxidant activity and oxygen radical absorbance capacity). The ethanolic extract of the peel showed significant effect on reducing the tumoral cell growth and proliferation. Antiproliferative activity of phytochemicals showed no significant correlative relations with total phenolic compounds, flavonoids and anthocyanins, demonstrating which the antiproliferative effect of the extract could be due to the synergic action among the compounds in red-jambo peel.
Assuntos
Antioxidantes/farmacologia , Proliferação de Células/efeitos dos fármacos , Frutas/química , Extratos Vegetais/farmacologia , Syzygium/química , Antioxidantes/química , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Extratos Vegetais/químicaRESUMO
Inflammatory bowel diseases are characterized by impaired intestinal barrier function. This study aimed to evaluate the effects of grape peel powder (GPP) and its bioactive rich-fractions on the barrier function and colonic injury in a model of colitis induced by 2,4,6 trinitrobenzene sulfonic acid (TNBS). Wistar rats received diets supplemented with either GPP (8%), extractable polyphenols (EP), non-extractable polyphenols-rich fraction (NEP-F), or polyphenols-poor, fiber-rich fraction (F) from grapes at amounts equivalent to the GPP group during 15â¯days before and for 7â¯days after colitis induction. NEP-F has decreased the extension of colonic lesion but the other grape peel bioactive fractions did not protect against macroscopic or microscopic colonic damage, EP diet increased macroscopic colonic damage. GPP, EP, and NEP-F reduced claudin-2 mRNA expression, whereas GPP and F fraction increased occludin and ZO-1 mRNA expression. All experimental diets reduced the colitis-triggered increase of MMP-9 mRNA expression. Colitis reduced by 30% the production of cecal short-chain fatty acids (SCFA). GPP and NEP-F completely protected against this effect, whereas F fraction was ineffective. Only GPP and NEP-F were able to decrease the upregulation of GRP94 mRNA triggered by colitis. Dietary fiber seems to reestablish the intestinal barrier function, whereas fiber-bound phenolics were able to restore cecal metabolism to produce beneficial metabolites like SCFA and to reduce the activation of the unfolded protein response.