Investigation of Antioxidant Potential of Black Beans Due to Phytochemical and Globulin Content for Nutraceutical Application

The study aims to elucidate the antioxidant and anti-inflammatory properties of black beans and identify the key contributors within the beans. Black beans boast high protein and phytochemical content, suggesting potential antioxidant activity. This work delves into this possibility, focusing on the role of globulins (a protein fraction) and various phytochemicals in black bean’s bioactivity. Globulins were isolated from black beans by salt precipitation. Ethanolic and aqueous extracts were prepared, followed by phytochemical screening for phenolics, flavonoids, alkaloids, etc. Quantification of phenolics and flavonoids was performed by colorimetric assays. SDS-PAGE and mass spectrometry identified the isolated globulin. Ferric reducing potential and total antioxidant capacity tests assessed antioxidant capacity, while erythrocyte membrane stabilisation inhibition evaluated anti-inflammatory potential. Black beans exhibited a diverse range of phytochemicals. The ethanolic extract displayed the highest flavonoid content (11.18±0.11mg QE/gram extract), while the aqueous extract was richest in phenolics (0.71±0.14 mg GAE/gram extract). The aqueous extract displayed the strongest antioxidant activity (2.87 ± 0.98 mg AAE/gram extract), followed by the globulin fraction (1.23± 0.43 mg AAE/gram extract). The ethanolic extract demonstrated superior anti-inflammatory activity. Mass spectrometry identified globulin as a 68.7 kDa legumin protein from Phaseolus vulgaris. Black beans display significant antioxidant and anti-inflammatory activity due to globulins and diverse phytochemicals. By informing dietary practices and facilitating the development of nutraceutical interventions, this work has the potential to contribute to a healthier population.