Đánh giá sự đa dạng di truyền và tính kháng khuẩn của cây từ bi (Blumea balsamifera Lindl.)

Abstract

The genetic diversity and the antibacterial activity of Blumea balsamifera Lindl. was evaluated on 15 plants collected in different places in Mekong Delta (Vinh Long, Can Tho, Soc Trang, Tra Vinh, Dong Thap, Bac Lieu, and Hau Giang). Their leaves were used for analyzing genetic diversity employing RAPD (Random Amplified Polymorphic DNA) markers and testing the antibacterial susceptibilities expressed as minimum inhibitory concentrations (MIC) of eight selected Gram positive and Gram negative strains: Staphylococcus aureus, Streptococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Salmonella spp., Aeromonas hydrophila, Edwardsiella ictaluri and Edwardsiella tarda by agar dilution method. Results showed that, the polymorphism of 15 Blumea balsamifera is greatly diversed and was divided into 4 groups with the genetic distance from 1.414 to 5.196. All of them demonstrated the efficacy of antibacterial activity. The highest antibacterial potentials were observed on Edwardsiella tarda (MIC=256 µg/ml), and subsequently on Edwardsiella ictaluri (256 µg/ml ≤ MIC ≤ 512 µg/ml, best in group 3) and on Staphylococcus aureus (512 µg/ml ≤ MIC ≤ 1024 µg/ml, most of them with MIC=512 µg/ml). B. balsamifera was found less effective on Pseudomonas aeruginosa and Aeromonas hydrophila (1024 µg/ml ≤ MIC ≤ 2048 µg/ml), Streptococcus faecalis (1024 µg/ml ≤ MIC ≤ 4096 µg/ml), and least effective on Escherichia coli (2048 µg/ml ≤ MIC >4096 µg/ml) and Salmonella spp. (MIC=4096 µg/ml).