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)

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 Ardisia silvestris extracts. The antibacterial properties of Ardisia silvestris tested against of Staphylococcu saureus, Samonella sp., and Escherichia coli were determined by using agar diffusion method. The agar diffusion 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, alkaloids, flavonoids, coumarins, tannins, anthocyanoids, carotenoids, organic acids, reducing agents, proanthocyanidins, saponins and anthraquinones. Ardisia silvestris leaves had a total polyphenol content of 0.26% dry matter, 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 concentration of 100 µl/ml ranged between 9.67mm and 20.67mm for ethyl acetate and ethanol extracts, respectively on E.coli. Similarly, the zones of inhibitionof ethyl acetate and ethanol extracts diameters were 14.67 and 15.33 mm, respectively on Samonella sp., however, it was not shown for Staphylococus aureus