Green extraction and biological activity of phenolic extracts from cashew nut testa using a combination of enzyme and ultrasound‐assisted treatments
Hoàng Văn Thành, Nguyen Thi Lan Phi, Nguyen Tien Khoi, Nguyen Xuan Hoan, Pham Van Hung
Abstract
Abstract BACKGROUND A combination of enzymes and ultrasound treatment was employed to extract bioactive compounds from cashew nut testa, a by‐product of the food industry. The total catechin, flavonoid, and phenolic content of extracts was investigated together with their biological activity. RESULTS Enzyme and ultrasound‐assisted extraction (E‐UAE) was performed by incubation with Viscozyme L (20 mL kg −1 of testa powder, v/w) for 60 min before sonication for 40 min. Ultrasound and enzyme‐assisted extraction (U‐EAE) was carried out using sonication for 40 min before incubation with Viscozyme L (20 mL kg −1 of testa powder) for 60 min. Under appropriate conditions, the total phenolic, flavonoid, catechin, and epigallocatechin gallate content of the extracts from cashew nut testa obtained from a combination method (U‐EAE or E‐UAE) was significantly higher than that obtained using a single method (EAE or UAE). Extracts of cashew nut testa obtained from E‐UAE displayed significantly higher antioxidant and α ‐amylase inhibitory activity than those from the U‐EAE. The E‐UAE extract at a concentration of 100 μg mL −1 had a greater impact on the cell viability of MCF‐7 after treatment (22% cell viability) than did the doxorubicin (DOX) at 4 μg mL −1 (39% cell viability), and the E‐UAE extract at 100 μg mL −1 was considered to be safe for healthy cells because the viability of the bovine aerotic endothelial cells treated with this extract was 91%, which was similar to the DOX treatment. CONCLUSION The extract of cashew nut testa obtained from E‐UAE is valuable and promising for the development of anti‐inflammatory therapeutic drugs. © 2023 Society of Chemical Industry.