ERJON MAMOCI1*, ANISA PECULI2, MARIA FE ANDRÉS3, AZUCENA GONZÁLEZ-COLOMA3
1Department of Food Science and Biotechnology, Faculty of Biotechnology and Food, Agricultural University of Tirana, Kodër Kamëz, 1029 Tirana, Albania
2Department of Agro-Food Technology, Faculty of Biotechnology and Food, Agricultural University of Tirana, Kodër Kamëz, 1029 Tirana, Albania
3Instituto de Ciencias Agrarias. Consejo Superior de Investigaciones Científicas. Serrano 115-bis, 28006 Madrid, Spain
The present study shows the chemical composition, antifungal, antibacterial and radical scavenging effect of the essential oil from wild Thymus vulgaris L. Chemical analysis of essential oil was done by gas chromatography mass spectrometry (GC-MS). Antibacterial activity was tested using disc diffusion method on three food borne diseases while antifungal activity was tested on colony growth of three postharvest pathogens in volatile phase. The free radical scavenging activity of the oil was measured in vitro by 2,20- diphenyl-1-picrylhydrazyl (DPPH) assay. GC-MS analysis identifies 30 components with thymol and p-cymene as main component, 35.4 and 26.93% respectively. The oil of thyme (5 L/disc) gave higher inhibition zones on the tested bacterial strains, Escherichia coli ATCC 25922, Salmonella typhimurium ATCC 14028 and Staphylococcus aureus ATCC 6538 compared with antibiotic cefazolin (30 g/disc). In volatile phase, thyme oil (0.14 g/L) showed good antifungal activity on Penicillium italicum, P. digitatum and P. expansum, with percentages of mycelial inhibition 60, 71.4 and 73.5% respectively. The activity of the oil was fungistatic. Scavenging effect of the oil on DPPH radical varied from 36.4, 50.5 and 76.1% depending the concentrations used (1, 2 and 5 mg/mL). The in vitro biological activity of thyme oil can be attributed to aromatic monoterpenes thymol and p-cymene.
Keywords: Thymus vulgaris, thymol, p-cymene, antibacterial, antifungal, DPPH