Articles
GC/MS INVESTIGATION OF ESSENTIAL OILS
These essential oils contain 60–90 % of artemisia ketone, or piperitone, or umbellulone, or chrysanthenol and chrysanthenyl acetate, or lyratol and lyratyl acetate, or thujone, or davanone etc which can be distinguished by their mas spectra.
We examined many variations of Tagetes species like T. erecta, T.lucida, T.minuta, T.patula and T.tenuifolia (family: ASTERACEAE) and characteristic differences have been determined on analysing their essential oils.
We found 
-ocimene only in T.minuta; tagetone; dihydrotagetone and ocimenones (high amount) in T.minuta and T.tenuifolia. The oil of T.lucida has alone methyl chavicole component (80 %); T.patula and T.erecta usually contain limonene, 
– terpinolene, piperitone, and caryophyllene components.
In the course of GC/MS studies of Achillea species (family: ASTERACEAE) we found some very interesting differences within species originating from another geographical area. Achillea crithmifolia oils are characterized by camphor and borneol, but populations from Mátra mountains are characterized by a high amount of ascaridol. A.nobilis generally contains an essential oil with high camphor, borneol and piperitone contituents. A. crithmifolia, A. nobilis, A. ochroleuca, A. pannonica, A. distans, A. filipendulina, A. ptarmica oils have been colourless.
The main component of A. asplenifolia and A. collina oils is chamazulene, with a molecular mass 184.
Determining the antibacterial and antifungal activities of essential oils using the agar diffusion and the atmospheric methods it was found that the multiplication of Gram+ bacterium and fungus starains was completely (100 %) inhibited.