Antimicrobial Activity of Thai Herb Extracts Against Coconut Milk Spoilage Microorganisms

Abstract

Twenty-five Thai herb extracts were determined for their antimicrobial activities against 11 coconut milk spoilage microorganisms by an agar-well diffusion method. The results showed Piper betle (Betle vine) could inhibit all strains of the test bacteria. However, Phyllanthus emblica (Malacca tree), Senna siamea (cassod tree) and Punica granatum (pomegranate) exhibited greater significant (P ≤ 0.05) antimicrobial activity when compared with other herb extracts, with the zone of inhibition ranging from 12.33±0.58 to 25.00±1.73 mm. The ethanol extracts of the three herbs (Malacca tree, cassod tree, pomegranate) were the most efficient antimicrobial compounds. The values of minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum fungicidal concentration (MFC) of the herb extracts were 0.3-2.4, >3 and 1.2-2.4% (w/v), respectively.