Essential oil components of some Hypericum species and antimicrobial activity of this oils

VI SUMMARY In this study, essential oil constituents obtained from Hypericum hyssopifolium Chaix var. microcalysinum Boiss&Heldr, Hypericum scabroides Robson&Poulter, Hypericum scabrum L., Hypericum lysimachioides Boiss var. lysimachioides, Hypericum triquetrifolium Turra. that collected from Southeastern Anatolia region were identified and oü obtained were tested in respect of their antibacterial and antifungal activity against different microorganism. Essantial oils were isolated by Cockins and Middletons Apparatus. Essential oil constituents were identified by GC/MS. Caryophyllene oxide from H. hyssopifolium var. microcalysinum, H triqetrifolium and H. lysimachioides var. lysimachioides, bicyclohept-3-en-2- on from H. scabroides and H. scabrum were obtained as major components. The antimicrobial activity of the olis of Staphylococcus aureus, Streptococcus pyogenes, Pseudomonas aeruginosa, yeast fungus Candida albicans, Escherichia coli K12, Escherichia coli PBr-322, Escherichia coli PUC9, Bacillus brevis ATCC and Bacillus cereus were tested by Paper Disc Diffusion Method. This study shows that the essential oils of these plants were exhibited antimicrobial activity against microorganism