Purified and HPCCC Fractionated Anthocyanin-Rich Extracts from Black Bean Hulls Modulate H2O2-Induced Intracellular ROS Generation in RAW 264.7 Cells

This study aimed to obtain crude, purified, and fractionated anthocyanin-rich extracts of three black bean cultivars from the South Pacific Region of Mexico (Chiapas, Guerrero, and Oaxaca). The extracts were obtained using an Amberlite XAD-7HP column and high-performance countercurrent chromatography (HPCCC), and their modulatory effect on oxidative stress was evaluated in RAW 264.7 macrophages. Purification significantly increased the concentrations of phenolic compounds and anthocyanins across all cultivars. However, HPCCC fractionation produced a cultivar-dependent response, with marked anthocyanin enrichment observed only in the Guerrero cultivar. In contrast, a decrease was noted for Oaxaca and Chiapas, compared with the corresponding purified extracts. The anthocyanin content per gram of extract ranged from 12.1 to 21.4 mg/g for crude extracts, 27.4 to 85.5 mg/g for purified extracts, and 48 to 98.8 mg/g for fractionated extracts. The purification and fractionation processes enabled the obtaining of anthocyanin-rich extracts from black bean hulls that reduced H2O2-induced intracellular ROS generation in a cultivar- and treatment-dependent manner, with the black bean cultivar from Chiapas being the most effective, indicating that differences in its phenolic composition may contribute to the observed biological response. These findings provide valuable insights into the potential of high-performance countercurrent chromatography for the fractionation of black bean anthocyanins.