Phân tích thành phần hóa thực vật và xác định khả năng chống oxy hóa và kháng khuẩn của dịch chiết từ lá của cây khôi nhung (Ardisia silvestris Pitard)

Abstract

The phytochemical analysis and antibacterial and antioxidant activity of Ardisia silvestris extracts were carried out. The bioactive compounds of Ardisia silvestris leaves were extracted with petroleum ether, ethyl acetate, ethanol and water by immersion and microwave method. The DPPH method was used to determine the antioxidant activity of Ar-disia silvestris extracts. The antibacterial properties of Ardisia silvestristested against of Staphylococcu saureus,Samonellasp., and Escherichia coli were determined by using agar diffusion method. The agar diffu-sion method was used to determine the antibacterial effects of both plant extracts on the test organisms. The results showed that Ardisia silvestris leaves contained compounds such as essential oils, fats, alka-loids, flavonoids, coumarins, tannins, anthocyanoids, carotenoids, organicacids, reducing agents, proanthocyanidins, saponins and anthraquinones. Ardisia silvestris leaves had a total polyphenol content of 0.26% dry mat-ter, tannin of 8.8%, and a total flavonoid of 1.44 mg/g. The ethyl acetate extract and water extract of the leaves had the antioxidant activity and were 4.2 and 4.4 times lower than ascorbic acid, respectively. The ethyl acetate extract of Ardisia silvestris had the highest oxidative activity. The zone of inhibition of the plant extract diameters at the concentra-tion of 100μl/ml ranged between 9.67mm and 20.67mm for ethyl acetate and ethanol extracts, respectively on E.coli. Similarly, the zones of in-hibitionof ethyl acetate and ethanol extracts diameters were 14.67 and 15.33 mm, respectively onSamonellasp., however, it was not shown for Staphylococus aureus.