Cooked common bean (Phaseolus vulgaris L.) flours exhibited antioxidant and anti-inflammatory effects in vitro

Common beans (Phaseolus vulgaris L.) are a staple food widely consumed in Mexico and around the world, offering numerous health benefits primarily due to their high content of protein, dietary fiber, and other components, including phenolic compounds, saponins, and phytosterols. Polyphenolic compounds have been linked to antioxidant and anti-inflammatory effects, making them targeted beneficial phytochemicals in plant-based foods. Since beans are typically cooked before consumption, this research aimed to assess the antioxidant and anti-inflammatory properties of cooked common beans in vitro. Beans were digested in vitro, and the colonic fraction was evaluated in RAW 264.7 cells treated with lipopolysaccharide (LPS, 1 µg/mL) for 24 hours (post-treatment). Cooked flour contained 18.87% protein and 69.97% total carbohydrates, of which 85% was quantified as total dietary fiber. Gallic acid and (+)-catechin were the most abundant phenolic compounds in the colonic fraction, which showed antioxidant capacity as measured uing the ABTS and DPPH methods (4.65-7.66 µmol Trolox equivalents per gram of sample). When LPS-induced RAW 264.7 cells were challenged with various concentrations of the extract, dilutions up to 30% v/v were not cytotoxic (metabolic activity > 80%) and significantly (p<0.05) reduced nitrite content by up to 60%. A blank of digestion (digested and fermented water, dissolved in DMEM) was also tested and showed no cytotoxic effects on the cells. These results suggest that the anti-inflammatory and antioxidant effects of cooked common bean flours make them a promising functional ingredient with potential health benefits.