ĐÁNH GIÁ HOẠT TÍNH KHÁNG OXY HÓA VÀ MỘT SỐ HOẠT TÍNH SINH HỌC CỦA CAO LÁ CÂY PHÈN ĐEN (PHYLLANTHUS RETICULATUS)

Abstract

Background: Phyllanthus reticulatus is a wild plant commonly found along fences or abandoned are as throughout Vietnam, from North to South. In traditional medicine, this plant is used for treating enteritis, diarrhea, hepatitis, nephritis, fever, abscesses, bruises, and inflammatory conditions caused by inner heat. While previous international studies have demonstrated its antioxidant, anti inflammatory, analgesic, antibacterial, and antidiabetic activities, In Vietnam, no published research has yet investigated the biological activities of P. reticulatus leaves. Objective: To evaluate the antioxidant potential of ethanol extracts of P. reticulatus leaves, as well as their α-glucosidase inhibitory activity and antibacterial effects of leaves. Materials and methods: Ethanol extracts of P. reticulatus leaves were collected from Ninh Kieu District, Can Tho City. Antioxidant activity was assessed using the DPPH radical scavenging assay. The in vitro α-glucosidase inhibitory activity was determined by UV– Vis spectrophotometry, while antibacterial activity was evaluated using the agar diffusion method. Results: The ethanol extract of P. reticulatus leaves exhibited strong antioxidant activity, with a half maximal inhibitory concentration EC₅₀ of 96.84 μg/mL in the DPPH assay. The α-glucosidase inhibitory activity was recorded with an IC₅₀ of 67.00 μg/mL, compared to the positive control acarbose (IC₅₀ = 3.97 μg/mL). The extract also inhibited bacterial growth at concentrations ranging from 25 to 1000 μg/mL. Notably, inhibition zones greater than 10 mm were observed against S.aureus, E.coli, and P.aeruginosa at extract concentrations of 25, 50, and 100 μg/mL, respectively. Conclusion: This study demonstrates that ethanol extracts of P. reticulatus leaves represent a promising natural source of strong antioxidants, exhibit significant α-glucosidase inhibitory activity with potential applications in diabetes management, and show marked antibacterial effects against S.aureus, E.coli, and P.aeruginosa, indicating their potential for use in preventing bacterial infections.