The aims of this work are to investigate the chemical composition, the antibacterial activity of the essential oil and the chromosome numbers of two populations of Hertia cheirifolia. The samples were collected in the flowering stage, in eastern Algeria locality. The aerial parts of H. cheirifolia were submitted to a hydro-distillation. GC and GC / MS analysed the chemical compositions of the obtained essential oils. The antibacterial activity of essential oils was evaluated using the disks diffusion method against ten bacterial strains. For karyotypic analysis, the squashing method is used. Fifty-eight compounds representing 98.93% of the total oil were identified in H. cheirifolia. The chemical composition is dominated by the presence of major products, α-pinene (48.49 - 53.85%) and Germacrene-D (2.64 - 12.66%). Two distinct chemical breeds were identified, the α-pinene-spathulenol of Batna population, and the α-pinene-germacrene-D of Setif population. The essential oil of H. cheirifolia has a moderate activity against bacteria tested. In contrast, the strains E. coli ATCC 25922, P. syringae ATCC 53543 and E. fecalis ATCC 49452 are resistant to H. cheirifolia essential oils. The observations of root cells meristematic at metaphase of H. cheirifolia gave a diploid chromosome number 2n = 2x = 20, with a basic chromosome number (x= 10).
The essential oil of the aerial parts of Thymus ciliatus (Desf.) belonging to the Lamiaceae family, was obtained by steam distillation and analyzed by GC-FID and GC-MS. 75 components were identified corresponding to 95.57% of the total oil. The major constituents of the oil were: elemol (6.80%), carvacrol (5.86%), γ-muurolene (5.18%), β-sesquiphellandrene (5.09%), bicyclogermacrene (5.04%), β-pinene (4.49%) and curcumene (4.20%), together with other compounds at relatively low levels: 1,8-cineol (3.66%), β-eudesmol (2.92%), β-bisabolene (2.81%), β-silinene (2.75%), camphor (2.64%), germacrone (2.34%), α-zingiberene (2.12%), δ-cadinene (2.08%), caryophyllene oxide (1.90%), spathulenol (1.88%), □-caryophyllene (1.88%), ar-turmerone (1.79%), α-pinene (1.52%), limonene (1.52%), selina-4,11-diene (1.46%), curzerenone (1.41%), germacrone B (1.37%), bornyl acetate (1.31%), β-farnesene (1.28%), borneol (1.23%), myrtenal (1.16%), zingiberenol (1.15%) and sabinene (1.13%). These results differ from those of previous studies reported on this species collected from other regions of Algeria and Morocco.
This study was aimed to determine the chemical composition of essential oils obtained from aerial parts of Thymus algeriensis Boiss. & Reut. and Marrubium vulgare L. collected in the Aures region of Algeria. Essential oils were extracted by steam distillation method and analyzed using GC-MS and GC-FID techniques. Thirty-five (35) and twenty-nine (29) components were identified respectively in T. algeriensis and M. vulgare essential oils to represent respectively 94.8% and 75.7% of the total oil composition. The main compounds of T. algeriensis oil were germacrene D (29.6%), β-caryophyllene (11.0%), E-β-farnesene (7.8%), bicyclogermacrene (4.4%) and δ-cadinene (4.0%), while, β-bisaboene (36.3%), β-caryophyllene (7.8%), phytol (6.2%), nonacosane (4.0%) and heptacosane (3.3%) were the main components of M. vulgare oil. The richness of these two oils in germacrene D and β-bisaboene respectively could suggest a new bioactivity.