Antibacterial activity of thai medicinal plant extracts on the skin infectious microorganisms

Abstract

Five Thai medicinal plants, Acanthus ilicifolius Linn. var. ilicifolius (leaves); Argyreia nervosa (Burm. f.) Bojer (leaves); Punica granatum L. var. granatum (fruit rind); Terminalia chebula Retz. var. chebula (fruits) and Zanthoxylum myriacanthum Wall. ex Hook. F. (fruits) were extracted by several extracting procedures with various solvents. We obtained 21 plant extracts that were tested for their antibacterial activities against Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 by well diffusion method. The active extracts were found out for minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) by broth dilution method. The results revealed that the ethanolic extract of Punica granatum L. var. granatum by maceration (PG-1), possed the most outstanding in vitro antibacterial activity. The MIC of PG-1 against S. aureus ATCC 25923 and E. coli ATCC 25922 were 0.39 and 12.5 mg/ml whereas the MBC were 1.56 and 12.5 mg/ml, respectively. The preliminary phytochemical study of PG-1 indicated that PG-1 contains both hydrolysable and condense tannin. © ISHS 2005.