RESUMEN
In recent years, there has been a growing interest in the screening of natural active ingredients from Eucalyptus essential oils because of their evident importance in practical utility and their undeniable therapeutic properties. Based on this, the aim of the present study was to investigate the chemical profile of the essential oils of the trunk bark of Eucalyptus torquata Luehm. (ETEO), and E.â salmonophloia F.â Muell. (ESEO), growing in Tunisia. The inâ vitro cytotoxic properties of the extracted EOs were also evaluated against two human cancer cell lines: breast carcinoma cell lines MDA-MB-231 and colorectal cancer cell lines SW620. The analysis by gas chromatography coupled with mass spectrometry (GC/MS) led to the identification of 32 compounds from the ETEO, with the dominant constituents being the monoterpenes trans-myrtanol (73.4 %) and myrtenol (4.7 %), and the apocarotene (E)-ß-ionone (3.9 %). In the case of ESEO, 29 compounds were identified with trans-myrtanol (25.0 %), decanoic acid (22.1 %), nonanoic acid (9.8 %), γ-elemene (6.5 %), γ-maaliene (5.5 %), and α-terpineol (5.3 %) as the main components. The cytotoxicity of EOs against the two chosen cell lines was tested using Crystal Violet Staining (CVS) assay and 5-fluorouracil as a reference drug. The two EOs exhibited a significant dose-dependent inhibition against the viability of the used cell lines. Their inhibitory effects were particularly observed towards SW620 colon carcinoma cells with IC50 values of 26.71±1.22 and 22.21±0.85â µg/mL, respectively, indicating that both oils were more cytotoxic for SW620 cells compared to MDA-MB-231 one.
Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Eucalyptus/química , Aceites Volátiles/farmacología , Componentes Aéreos de las Plantas/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Aceites Volátiles/química , Aceites Volátiles/aislamiento & purificaciónRESUMEN
Pistacia lentiscus L. seed oil is used in some Mediterranean forest area for culinary and medicinal purposes. In this study, we aim to examine, for the first time, the effect of growing area on sterol content of Pistacia lentiscus seed oil. Fruits were harvested from 13 different sites located in northern and central Tunisia. Gas chromatography-flame-ionization detection (GC-FID) was used to quantify sterols and gas chromatography/mass spectrometry (GC/MS) was used to identify them. The major sterol identified was ß-sitosterol with a value ranging from 854.12 to 1224.09 mg/kg of oil, thus making up more than 54% of the total sterols. The other two main sterols were cycloartenol (11%) and 24-methylene-cycloartenol (5%). Statistical results revealed that growing location significantly (P < 0.001) affected phytosterol levels in these oils.
Asunto(s)
Pistacia/química , Aceites de Plantas/química , Semillas/química , Esteroles/análisis , Cromatografía de Gases , Espectrometría de Masas , Conformación Molecular , TúnezRESUMEN
BACKGROUND: In this paper, we have studied the essential oils chemical composition of the leaves of seven Eucalyptus species developed in Tunisia. Eucalyptus leaves were picked from trees growing in different arboretums in Tunisia. Choucha and Mrifeg arboretums located in Sedjnene, region of Bizerte (Choucha: E. maideni, E. astrengens et E. cinerea; Mrifeg : E. leucoxylon), Korbous arboretums located in the region of Nabeul, North East Tunisia with sub-humid bioclimate, (E. lehmani), Souiniet-Ain Drahem arboretum located in region of Jendouba (E. sideroxylon, E. bicostata). Essential oils were individually tested against a large panel of microorganisms including Staphylococcus aureus (ATCC 6539), Escherichia coli (ATCC 25922), Enterococcus faecalis (ATCC29212), Listeria ivanovii (RBL 30), Bacillus cereus (ATCC11778). RESULTS: The yield of essential oils ranged from 1.2% to 3% (w/w) for the different Eucalyptus species. All essential oils contain α-pinene, 1,8-cineol and pinocarveol-trans for all Eucalyptus species studied. The 1,8-cineol was the major compound in all species (49.07 to 83.59%). Diameter of inhibition zone of essential oils of Eucalyptus species varied from 10 to 29 mm. The largest zone of inhibition was obtained for Bacillus cereus (E. astrengens) and the lowest for Staphylococcus aureus (E. cinerea). The essential oils from E. maideni, E. astrengens, E. cinerea (arboretum of Bizerte), E. bicostata (arboretum of Aindraham) showed the highest antibacterial activity against Listeria ivanovii and Bacillus cereus. CONCLUSION: The major constituents of Eucalyptus leaves essential oils are 1,8-cineol (49.07 to 83.59%) and α-pinene (1.27 to 26.35%). The essential oils from E. maideni, E. astrengens, E. cinerea, E. bicostata showed the highest antibacterial activity against Listeria ivanovii and Bacillus cereus, they may have potential applications in food and pharmaceutical products.
Asunto(s)
Antibacterianos/farmacología , Eucalyptus/química , Eucalyptus/clasificación , Aceites Volátiles , Hojas de la Planta/química , Bacillus cereus/efectos de los fármacos , Monoterpenos Bicíclicos , Proliferación Celular/efectos de los fármacos , Ciclohexanoles/análisis , Enterococcus faecalis/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Eucaliptol , Cromatografía de Gases y Espectrometría de Masas , Listeria/clasificación , Listeria/efectos de los fármacos , Monoterpenos/análisis , Aceites Volátiles/química , Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Staphylococcus aureus/efectos de los fármacos , TúnezRESUMEN
The relevance of oxylipins as biomarkers of oxidative stress has been established in recent years. Phytoprostanes and phytofurans are plant metabolites derived from peroxidation of α-linolenic acid (ALA) induced by ROS. Previous findings have suggested new valuable biological properties for these new active compounds in the frame of diverse pathophysiological situations and health constraints. Lipidomic profiling of different aerial parts of the same Acacia cyanophylla Lindl. specimen, was evaluated for the first time here, using LC-MS/MS technology. Analysis revealed the existence of six PhytoPs and three PhytoFs. Stems have the highest amount of these metabolites with 179.35 ng/g and 320.79 ng/g respectively. This first complete profile paves the way to explore Acacia cyanophylla Lindl. as a source of plant oxylipins for therapeutic or pharmaceutical uses.
Asunto(s)
Acacia , Oxilipinas , Espectrometría de Masas en Tándem , Cromatografía Liquida , Estructura Molecular , Extractos Vegetales , Componentes Aéreos de las PlantasRESUMEN
The essential oils isolated from leaves, wood, and cones of the Tunisian endemic cypress Cupressus sempervirens L. var. numidica Trab. collected from three natural populations were characterized by GC-FID and GC/MS analyses. In the wood, leaf, and cone oils, 38, 35, and 26 constituents, representing 94.4, 97.8, and 98.5% of the total oil composition, respectively, were identified. Monoterpenes constituted the major fraction of the oils from all organs and for all populations. The oils were found to be of an α-pinene (64.2%)/δ-car-3-ene (11.1%) chemotype with considerable contents of α-humulene (3.4%) in the leaf oil, cedrol (2.8%) in the wood oil, and sabinene (3.2%) in the cone oil, respectively. α-Pinene, δ-car-3-ene, limonene, carvacrol methyl ether, α-humulene, and α-amorphene were the main components that differentiated the oils of the three organs in the cypress of Makthar.
Asunto(s)
Cupressus/química , Aceites Volátiles/química , Análisis por Conglomerados , Cromatografía de Gases y Espectrometría de Masas , Aceites Volátiles/aislamiento & purificación , Hojas de la Planta/química , Tallos de la Planta/química , TúnezRESUMEN
BACKGROUND: In 1957, Tunisia introduced 117 species of Eucalyptus; they have been used as fire wood, for the production of mine wood and to fight erosion. Actually, Eucalyptus essential oil is traditionally used to treat respiratory tract disorders such as pharyngitis, bronchitis, and sinusitis. A few investigations were reported on the biological activities of Eucalyptus oils worldwide. In Tunisia, our previous works conducted in 2010 and 2011 had been the first reports to study the antibacterial activities against reference strains. At that time it was not possible to evaluate their antimicrobial activities against clinical bacterial strains and other pathogens such as virus and fungi. METHODS: The essential oils of eight Eucalyptus species harvested from the Jbel Abderrahman, Korbous (North East Tunisia) and Souinet arboreta (North of Tunisia) were evaluated for their antimicrobial activities by disc diffusion and microbroth dilution methods against seven bacterial isolates: Haemophilus influenzae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pneumoniae and Streptococcus pyogenes. In addition, the bactericidal, fungicidal and the antiviral activities of the tested oils were carried out. RESULTS: Twenty five components were identified by GC/FID and GC/MS. These components were used to correlate with the biological activities of the tested oils. The chemical principal component analysis identified three groups, each of them constituted a chemotype. According to the values of zone diameter and percentage of the inhibition (zdi, % I, respectively), four groups and subgroups of bacterial strains and three groups of fungal strains were characterized by their sensitivity levels to Eucalyptus oils. The cytotoxic effect and the antiviral activity varied significantly within Eucalyptus species oils. CONCLUSIONS: E. odorata showed the strongest activity against S. aureus, H. influenzae, S. agalactiae, S. pyogenes, S. pneumoniae and against all the tested fungal strains. In addition, E. odorata oil showed the most cytotoxic effect. However, the best antiviral activity appeared with E. bicostata. Virus pretreatment with E. bicostata essential oil showed better antiviral activity (IC(50) = 0.7 mg/ml, SI = 22.8) than cell-pretreatment (IC(50) = 4.8 mg/ml, SI = 3.33). The essential oil of E. astringens showed antiviral activity only when incubated with virus prior to cell infection. This activity was dose-dependent and the antiviral activity diminished with the decreasing essential oil concentration.
Asunto(s)
Antiinfecciosos/farmacología , Eucalyptus/química , Aceites Volátiles/química , Aceites Volátiles/farmacología , Aceites de Plantas/química , Aceites de Plantas/farmacología , Antiinfecciosos/química , Bacterias/efectos de los fármacos , Eucalyptus/clasificación , Hongos/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Virus/efectos de los fármacosRESUMEN
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, ß-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. A correlation between the levels of some major components and the antibacterial activities was observed.
Asunto(s)
Antibacterianos/química , Eucalyptus/química , Aceites Volátiles/química , Hojas de la Planta/química , Aceites de Plantas/química , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Análisis por Conglomerados , Pruebas Antimicrobianas de Difusión por Disco/normas , Gentamicinas/farmacología , Modelos Biológicos , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Análisis de Componente Principal , Estándares de Referencia , TúnezRESUMEN
BACKGROUND: In order to investigate new sources of dietary phytochemicals, recent studies have focused on underexploited seeds. In this study the total lipid contents, fatty acid profiles and levels of soluble proteins, minerals and antioxidants in seeds from 12 Acacia cyanophylla ecotypes commonly grown in Tunisia were determined. RESULTS: Total lipids averaged 101.7 g kg(-1) on a dry weight basis. Linoleic (61.11-65.45% of total fatty acid content), oleic (19.67-22.85%) and palmitic (9.18-9.98%) acids were the principal fatty acids. Smaller proportions of stearic (1.49-1.82%), vaccenic (1.13-2.05%) and palmitoleic (0.34-0.58%) acids were also quantified. Proteins (by Kjeldahl assay) averaged 107.2 g kg(-1) on a dry weight basis. Total phenolics averaged 1.91 g gallic acid equivalent kg(-1) dry weight (DW) and total flavonoids averaged 0.40 g rutin equivalent kg(-1) DW. The free radical-scavenging activity determined by 2,2-diphenyl-1-picrylhydrazyl assay averaged 0.59 mmol L(-1) Trolox equivalent antioxidant capacity (TEAC), while that determined by 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assay averaged 0.28 mmol L(-1) TEAC. CONCLUSION: The findings of this study confirm the presence of ω6 fatty acids at high levels in A. cyanophylla seeds. These metabolites could be used as such and/or extracted for the formulation of supplements and/or ingredients to provide a ratio close to the ideal for the ω3/ω6 balance.
Asunto(s)
Acacia/química , Antioxidantes/análisis , Dieta , Grasas de la Dieta/análisis , Ácidos Grasos Omega-6/análisis , Polifenoles/análisis , Semillas/química , Antioxidantes/metabolismo , Compuestos de Bifenilo/metabolismo , Proteínas en la Dieta/análisis , Ecotipo , Flavonoides/análisis , Humanos , Fenoles/análisis , Picratos/metabolismo , TúnezRESUMEN
Hydrodistillation of the dried leaves of five species of the genus Eucalyptus L' Hér., viz., E. dundasii Maiden, E. globulus Labill., E. kitsoniana Maiden, E. leucoxylon F. Muell., and E. populifolia Hook., harvested from Jbel Abderrahman arboreta (region of Nabeul, northeast of Tunisia) in April 2006, afforded essential oils in yields varying from 0.9±0.3 to 3.8±0.6%, dependent on the species. E. globulus and E. Kitsoniana provided the highest and the lowest percentage of essential oil amongst the species examined, respectively. Analysis by GC (RI) and GC/MS allowed the identification of 127 compounds, representing 93.8 to 98.7% of the total oil composition. The contents of the different samples varied according to the species. The main components were 1,8-cineole (2; 4.7-59.2%), followed by α-pinene (1; 1.9-23.6%), trans-pinocarveol (6; 3.5-21.6%), globulol (8; 4.3-12.8%), p-cymene (3; 0.5-6.7%), α-terpineol (1.5-4.5%), borneol (0.2-4.4%), pinocarvone (1.1-3.8%), aromadendrene (1.4-3.4%), isospathulenol (0.0-1.9%), fenchol (4; 0.1-2.5%), limonene (1.0-2.4%), epiglobulol (0.6-2.1%), viridiflorol (9; 0.8-1.8%), and spathulenol (0.1-1.6%). E. leucoxylon was the richest species in 2. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) separated the five Eucalyptus leaf essential oils into four groups, each constituting a chemotype.
Asunto(s)
Eucalyptus/química , Aceites Volátiles/química , Hojas de la Planta/química , Eucalyptus/clasificación , Cromatografía de Gases y Espectrometría de Masas , Monoterpenos/análisis , Aceites Volátiles/análisis , Filogenia , Aceites de Plantas/análisis , Aceites de Plantas/química , Análisis de Componente Principal , Sesquiterpenos/análisis , TúnezRESUMEN
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 ß-phellandrene. Principal components analysis and hierarchical cluster analysis separated the eight Eucalyptus leaf essential oils into five groups, each constituting a chemotype.
Asunto(s)
Mezclas Complejas/análisis , Eucalyptus/química , Aceites Volátiles/química , Hojas de la Planta/química , Mezclas Complejas/química , Destilación , Eucalyptus/clasificación , Cromatografía de Gases y Espectrometría de Masas , Italia , Monoterpenos/análisis , Marruecos , Aceites Volátiles/análisis , Filogenia , Aceites de Plantas/análisis , Aceites de Plantas/química , Análisis de Componente Principal , Sesquiterpenos/análisis , TúnezRESUMEN
Essential oils obtained by hydrodistillation from the different parts (stems, adult leaves, immature flowers and fruits) of Eucalyptus oleosa were screened for their antioxidant and antimicrobial properties and their chemical composition. According to GC-FID and GC-MS, the principal compound of the stem, immature flowers and the fruit oils was 1,8-cineole, representing 31.5%, 47.0% and 29.1%, respectively. Spathulenol (16.1%) and γ-eudesmol (15.0%) were the two principal compounds of adult leaves oil. In the DPPH (1,1-diphenyl-2-picrylhydrazyl) assay, the oils of the four parts showed moderate antioxidant activity. In the ABTS (2,2'-azinobis-3-ethylbenzothiazoline-6-sulphonate) assay, the most active part was the adult leaves, with a IC(50) value 13.0 ± 0.6 mg/L, followed by stems (IC(50) = 43.5 ± 1.4 mg/L). The essential oils showed a better antibacterial activity against Gram-positive and Gram-negative bacteria, and a significant antifungal activity also was observed against yeast-like fungi. A strong correlations between oxygenated monoterpenes and antimicrobial activity (especially 1,8-cineole) were noted (R2 = 0.99, 0.97 and 0.79 for B. subtilis, P. aeruginosa and C. albicans, respectively).
Asunto(s)
Antibacterianos , Antioxidantes , Eucalyptus , Aceites Volátiles , Antibacterianos/química , Antibacterianos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Eucalyptus/anatomía & histología , Eucalyptus/química , Flores/química , Radicales Libres/química , Frutas/química , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Aceites Volátiles/química , Aceites Volátiles/farmacología , Extractos Vegetales/análisis , Hojas de la Planta/química , Tallos de la Planta/químicaRESUMEN
The essential-oil composition of 60 individual trees of Juniperus phoenicea L. from four Tunisian populations in three different periods were investigated by GC and GC/MS analyses. 59 Compounds were identified in the oils, and a relatively high variation in their contents was found. All the oils were dominated by the terpenic hydrocarbon fraction, and the main component was alpha-pinene (20.28-40.86%). The results of the oil compositions were processed by hierarchical clustering and principal component analysis (PCA) allowing establishing four groups of essential-oils differentiated by one compound or more. Pattern of geographic variation in essential-oil composition indicated that individuals from the continental site (Makthar) were clearly distinguished from those from littoral localities (Tabarka, Hawaria, and Rimel).
Asunto(s)
Juniperus/química , Aceites Volátiles/química , Cromatografía de Gases y Espectrometría de Masas , Fenómenos Geológicos , Juniperus/clasificación , Aceites Volátiles/aislamiento & purificación , Hojas de la Planta/química , Análisis de Componente Principal , Estaciones del Año , TúnezRESUMEN
In this investigation, we aimed to study, for the first time, the phenolic composition of Pistacia lentiscus seed oils from different growing areas. Extraction of the phenolic fraction from oils was done by methanol/water. Phenolic profiles were determined using chromatographic analysis by High Performance Liquid Chromatography (HPLC-DAD/MSD) and its quantification was done using an internal standard which is unidentified in the studied oil (syringic acid). Forty phenolic compounds were quantified and only eighteen of them were identified. The eight studied oils showed different phenolic profiles. The total phenols amount varied from 538.03â¯mg/kg oil in Jbel Masour oils to 4260.57â¯mg/kg oil in oils from Kef Erraai. The highest amount of secoiridoids was reached by Bouchoucha oil containing 366.71â¯mg/kg oil of Oleuropein aglycon. Oils from Kef Erraai locality contained the highest concentrations in flavonols (377.44â¯mg/kg oil) and in phenolic acids (2762.67â¯mg/kg oil).
Asunto(s)
Cromatografía Líquida de Alta Presión , Fenoles/análisis , Pistacia/metabolismo , Aceites de Plantas/química , Flavonoles/análisis , Iridoides/análisis , Pistacia/química , Análisis de Componente Principal , Semillas/química , Semillas/metabolismoRESUMEN
In order to evaluate the potential of this formulation (P. lentiscus L. oil-based ointment) to heal wounds, experimental wounds were done on guinea pigs and efficiency was comparatively assessed against a reference ointment, Cicaderma®. Wound contraction was performed on days 5, 10 and 15. Tissue sections were also evaluated histopathological on days 7, 14 and 21. Results showed that for all days (5, 10 and 15), the highest wound contraction values were attained for the P. lentiscus oil-based ointment treated group with wound contraction values of 19.38, 55.8 and 77.11%, respectively, as compared to the reference drug Cicaderma® where contractions were 7.97%, 49.53% and 71.44%, respectively. Vehicle and negative control groups however showed no statistically significant wound healing activity on the excision wound model. These experimental studies revealed that the P. lentiscus oil-based ointment displays remarkable wound healing activity, in accordance with its use in traditional medicine.
Con el fin de evaluar el potencial de esta formulación (ungüento a base de aceite de P. lentiscus L.) para curar heridas, se realizaron heridas experimentales en cobayos y se evaluó comparativamente su eficacia respecto de un ungüento de referencia, Cicaderma®. La contracción de la herida se realizó los días 5, 10 y 15. Las secciones de tejido también se evaluaron histopatológicamente los días 7, 14 y 21. Los resultados mostraron que para todos los días (5, 10 y 15), se obtuvieron los valores más altos de contracción de la herida para el grupo tratado con ungüento a base de aceite de P. lentiscus con valores de contracción de la herida de 19.38, 55.8 y 77.11%, respectivamente, en comparación con el medicamento de referencia Cicaderma® en donde las contracciones fueron 7.97%, 49.53% y 71.44%, respectivamente. Sin embargo, los grupos de control de vehículo y negativo no mostraron actividad de curación de heridas estadísticamente significativa en el modelo de herida por escisión. Estos estudios experimentales revelaron que la pomada a base de aceite de P. lentiscus muestra una notable actividad de curación de heridas, de acuerdo con su uso en la medicina tradicional.
Asunto(s)
Animales , Masculino , Cobayas , Pomadas/farmacología , Cicatrización de Heridas/efectos de los fármacos , Aceites de Plantas/farmacología , Pistacia/química , SemillasRESUMEN
The most interesting factors associated with seed and cone production of Aleppo pine were largely reviewed to identify broad patterns and potential effectiveness of reforestation efforts and planning. Aleppo pine cone production and seed yields are relatively variable, with differences between spatial and temporal influences. These differences are considered, mainly between (i) year, (ii) stand characteristics and (iii) individual tree measurements. Annual variability among populations was recorded for cone production per tree, based on influencing factors such as genetic characteristics, wetness, nutrient availability, insect pests and disease. In addition, some factors may affect Aleppo pine tree growth directly but may be affecting seed and cone production indirectly. Therefore, reduced stand density results in less competition among Aleppo pine trees and accompanying understory flora, which subsequently increases the stem diameter and other tree dimensions, including seed production. This review suggests that reforestation planning, particularly thinning, will result in improved tree morphology that will increase Aleppo pine seed and cone crops. Wildfire intensity and stand conditions such as light and soil nutrient status are also examined.
Asunto(s)
Pinus/fisiología , Animales , Biomasa , Ecosistema , Incendios , Bosques , Frutas/crecimiento & desarrollo , Frutas/fisiología , Insectos , Pinus/genética , Pinus/crecimiento & desarrollo , Tallos de la Planta/crecimiento & desarrollo , Tallos de la Planta/fisiología , Reproducción , Semillas/crecimiento & desarrollo , Semillas/fisiologíaRESUMEN
BACKGROUND: In this paper, we have studied the essential oils chemical composition of the leaves of seven Eucalyptus species developed in Tunisia. Eucalyptus leaves were picked from trees growing in different arboretums in Tunisia. Choucha and Mrifeg arboretums located in Sedjnene, region of Bizerte (Choucha: E. maideni, E. astrengens et E. cinerea; Mrifeg : E. leucoxylon), Korbous arboretums located in the region of Nabeul, North East Tunisia with sub-humid bioclimate, (E. lehmani), Souiniet-Ain Drahem arboretum located in region of Jendouba (E. sideroxylon, E. bicostata). Essential oils were individually tested against a large panel of microorganisms includingStaphylococcus aureus (ATCC 6539), Escherichia coli (ATCC 25922), Enterococcus faecalis (ATCC29212), Listeria ivanovii (RBL 30), Bacillus cereus (ATCC11778). RESULTS: The yield of essential oils ranged from 1.2% to 3% (w/w) for the different Eucalyptus species. All essential oils contain α-pinene, 1,8-cineol and pinocarveol-trans for all Eucalyptus species studied. The 1,8-cineol was the major compound in all species (49.07 to 83.59%). Diameter of inhibition zone of essential oils of Eucalyptus species varied from 10 to 29 mm. The largest zone of inhibition was obtained for Bacillus cereus (E. astrengens) and the lowest for Staphylococcus aureus (E. cinerea). The essential oils from E. maideni, E. astrengens, E. cinerea (arboretum of Bizerte), E. bicostata(arboretum of Aindraham) showed the highest antibacterial activity against Listeria ivanovii and Bacillus cereus. CONCLUSION: The major constituents of Eucalyptus leaves essential oils are 1,8-cineol (49.07 to 83.59%) and α-pinene (1.27 to 26.35%). The essential oils from E. maideni, E. astrengens, E. cinerea, E. bicostatashowed the highest antibacterial activity against Listeria ivanovii and Bacillus cereus, they may have potential applications in food and pharmaceutical products.