1.Correlation between chemical composition and antibacterial activity of essential oils from fifteen Eucalyptus species growing in the Korbous and Jbel Abderrahman arboreta (North East Tunisia).
Elaissi A1, Rouis Z, Mabrouk S, Salah KB, Aouni M, Khouja ML, Farhat F, Chemli R, Harzallah-Skhiri F. Molecules. 2012 Mar 12;17(3):3044-57. doi: 10.3390/molecules17033044.
The essential oils of fifteen Eucalyptus species harvested from the Jbel Abderrahman and Korbous arboreta (North East Tunisia) were screened for their antibacterial activities by the agar disc diffusion method. Eighteen major components as identified by GC/FID and GC/MS were selected for a study of the chemical and biological activity variability. The main one was 1,8-cineole, followed by spathulenol, trans-pinocarveol, α-pinene, p-cymene, globulol, cryptone, β-phellandrene, viridiflorol, borneol, limonene and isospathulenol. The chemical principal component analysis identified five species groups and subgroups, where each group constituted a chemotype, however that of the values of zone diameter of the inhibition (zdi) identified six groups of Eucalyptus oils, characterized by their antibacterial inhibition ability. The strongest activity was shown by E. platypus oil against Enterococcus faecalis and by E. lamannii oil against Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli.
2.Variation in volatile leaf oils of seven eucalyptus species harvested from Zerniza arboreta (Tunisia).
Elaissi A1, Medini H, Simmonds M, Lynen F, Farhat F, Chemli R, Harzallah-Skhiri F, Khouja ML. Chem Biodivers. 2011 Feb;8(2):362-72. doi: 10.1002/cbdv.201000103.
Leaves of seven species of the genus Eucalyptus L'Hér., viz., E. cladocalyx F. Muell., E. citriodora Hook., E. diversicolor F. Muell., E. fasciculosa F. Muell., E. grandis W. Hill, E. ovata Labill., and E. botryoides Sm., were harvested from Zerniza arboreta (region of Sejnene, northwest of Tunisia) in June 2007. Of the latter species, leaves were collected from trees having two origins, Morocco and Italy. Hydrodistillation of the dried leaves provided essential oils in yields varying from 0.4±0.0 to 3.3±0.1%, according to the species. E. citriodora had the highest mean percentage of essential oil amongst the species examined, whereas the lowest one was obtained for E. botryoides originating from Morocco. Analysis by GC (RI) and GC/MS allowed the identification of 140 compounds, representing 92.5 to 99.4% of the total oil composition. The contents of the different samples varied according to the species. The main components were 1,8-cineole (2), followed by α-pinene (1), p-cymene, borneol, α-terpineol, cryptone, spathulenol, trans-pinocarveol (4), bicyclogermacrene (5), caryophyllene oxide, and β-phellandrene.
3.Chemical investigation and antimicrobial properties of mastic water and its major constituents.
Paraschos S1, Magiatis P2, Gousia P3, Economou V3, Sakkas H3, Papadopoulou C3, Skaltsounis AL1. Food Chem. 2011 Dec 1;129(3):907-11. doi: 10.1016/j.foodchem.2011.05.043. Epub 2011 May 12.
Mastic water is a commercial flavouring obtained during the steam distillation of mastic resin (the resin of Pistacia lentiscus var. chia) for the production of mastic oil. The mastic water extracts were analysed by GC-MS. The major compounds identified were verbenone, α-terpineol, linalool and trans-pinocarveol. Overall the composition was found to be very different from that of mastic oil. Additional GC-MS revealed the enantiomeric ratio of the chiral constituents of mastic water. The antimicrobial activity of mastic water extract, as well as that of its major constituents, was examined against Escherichia coli, Staphylococcus aureus and Candida spp. including ATCC wild clinical and food-borne strains. Linalool and α-terpineol were found to be the most potent antimicrobial constituents. Finally the stability of mastic water at different temperatures was studied, showing no change in the GC-MS profile of the organic extract for a period of 4months at storage temperatures up to 4°C.
4.Essential oil composition of Eucalyptus procera Dehnh. leaves from central Iran.
Rahimi-Nasrabadi M1, Ahmadi F, Batooli H. Nat Prod Res. 2012;26(7):637-42. doi: 10.1080/14786419.2010.541875. Epub 2011 Aug 24.
The chemical composition of the essential oil of leaves of Eucalyptus procera Dehnh., cultivated in central Iran, was obtained by hydrodistillation and analysed by GC-MS. Forty-five constituents representing 99.6% of the total oil were identified. The main constituents of the oil were found to be 1,8-cineole (35.9%), α-pinene (25.6%) and viridiflorol (7.7%). Other representative compounds were identified as α-terpineol (3.6%), aromadendrene (3.5%) and trans-pinocarveol (3.0%).