Antibacterial Activity of Extracts of Piper Betle Leaf

Abstract

Piper betle (L.) leaves were extracted employing the Soxhlet method. The crude extract samples obtained were: volatile oil, petroleum ether extract, ether extract, absolute alcohol and distilled water extracts. Each of these crude extract samples was tested for their inhibitory effects on the growth of 3 species of bacteria isolated from the outpatients who attended Outpatient Department at Siriraj Hospital Medical School from April 1982 to August 1982. The 3 species tested were Staphylococcus aureus (122 strains), Escherichia coli (31 strains) and Pseudomonas aeruginosa (57 strains). The results showed that S. aureus was the most sensitive microorganism to all extracts, while E. coli and Ps. aeruginosa showed similar reponse but somewhat less sensitive.

Among various extracts obtained from Piper betle leaves, volatile oil exhibited the highest inhibitory effect on the growth of the 3 species of bacteria tested; i.e., its MIC₉₀ against S. aureus was 1.7 μg/ml. Ether and petroleum ether extracts showed less potent activity having MIC₉₀ against S. aureus of 0.151 and 0.2 mg/ml., respectively. The antibacterial activity was found to be lowest in the water extract fraction.