Somaye Kanaani, Ali Mohamadi Sani, Fahime Yaghooti
Department of Food Science & Technology, Quchan Branch, Islamic Azad University, Quchan, Iran
Key words: Methanolic extract, Cotoneaster nummularioides Pojark, Sonchus arvensis L., Antibacterial activity, Essential oil.
This study was designed to compare the chemical composition of essential oils and the in vitro-antibacterial activities of methanolic extracts of Cotoneaster nummularioides Pojark and Sonchus arvensis L.. The essential oils were obtained by hydro-distillation and analyzed by gas chromatography-mass spectrometry (GC-MS). The GC-MS analysis of the essential oil revealed fifteen compounds for C. nummularioides Pojark and thirty-five compounds for S. arvensis L.. The agar disk diffusion method was used to study the antibacterial activity of C. nummularioides methanolic extract against four bacterial strains. Between these extracts only the extract of C. nummularioides Pojark showed antibacterial activity against two gram-positive microorganisms tested with higher sensitivity for Bacillus cereus (inhibition zones of 8 and 12 mm respectively for the concentration 300 and 400 mg/ml). Minimum Inhibitory Concentrations (MIC) and Minimum Bactericidal Concentrations (MBC) were quantified by macro-dilution method. The MIC was 3.125 and 50 mg/ml for Bacillus cereus and 6.25 and 50 mg/ml for Staphylococcus aureus, respectively. Overall, results presented here suggest that the methanolic extracts of C. nummularioides Pojark and Sonchus arvensis L. have antibacterial properties, and are therefore two potential sources of active ingredients for food and pharmaceutical industry.