Functional Mining of Echinocactus grusonii: Impact of Ethanol Solvents on the Recovery of Phenolic Acids and Radical Scavenging Potency

Abstract

Echinocactus grusonii (Golden Barrel Cactus; GBC), a cactus native to central Mexico, is gaining attention for its phytochemical content, which is high in compounds like lutein, flavonoids, phenolic acids, chlorophylls, and betalains. Many of these substances have antioxidant, anti-inflammatory, and anti-obesity effects. This study evaluated the impact of solvent extraction (60, 70, 80, 90% ethanol, acetonitrile, chloroform, and water) on antioxidant capacity and identified the phenolic profiles of Echinocactus grusonii crude extracts using HPLC. Antioxidant potentials were evaluated using the DPPH free radical scavenging capacity assay, ferric reducing antioxidant power assay, ABTS+ radical cation scavenging capacity assay, and ferrous ion chelating assay. The extracts with the most potent antioxidant effect were chosen for phenolic compound profiling. The 90% ethanol extract had the highest total phenolic content at 1254.40 ± 19.35 mg GAE/100 g RM, while the chloroform extract had the highest total flavonoid content at 777.5 ± 22.62 mg QE/100 g RM. Furthermore, the 90% ethanol extract demonstrated the highest antioxidant activity in all assays compared to the other extracts (p < 0.05). Additionally, HPLC analysis revealed the presence of various phenolic constituents, including gallic, protocatechuic, caffeic, p-coumaric, ferulic, sinapic, and rosmarinic acids, in the 90% ethanolic extract of Echinocactus grusonii. In conclusion, Echinocactus grusonii may be used as a medicinal plant from which antioxidants and anti-obesogenic compounds can be extracted for future commercial applications; therefore, in vitro anti-obesity efficacy studies should be carried out in the future.