Chemical Composition and Antibacterial Activity of the Essential Oil from the Seeds of Plectranthus hadiensis

Plectranthus is a large and widespread genus of Lamiaceae family with a diversity of ethnobotanical uses. In traditional medicine, the juice of stem and leaves of Plectranthus hadiensis which is mixed with honey is taken as a remedy for diarrhea. The aim of the present study is to determine the chemical composition of the essential oil from the seed of P. hadiensis and to evaluate antimicrobial efficacy of the oil. The essential oil of the seeds from P. hadiensis is obtained by hydro-distillation and analyzed by gas chromatography coupled with mass spectrometry (GC/MS). It results in the identification of 25 compounds representing 99.3%, of the total oil. The main compound is Piperitone oxide (33.33%). Antibacterial activity of the essential oil of P. hadiensis is tested against two Gram-positive and two Gram-negative bacteria, using zone of inhibition method. The essential oils inhibit the organisms and shows the zone of inhibition in the range of 20-35mm. The essential oil can serve as an antibacterial agent.