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This study was carried out to evaluate the effect of extraction methods (direct maceration (DM) and successive maceration (SM)) and solvents (dichloromethane (DCM), ethyl acetate (EAc), butanol (Bu...

Crithmum maritimum L., a species original from France and cultivated in Tunisia arid zones. In this study, we interested to the chemical composition and biological activities of essential oils from different parts of Crithmum maritimum L., . Theses oils were isolated by hydrodistillation and analyzed by GC and GC-MS. The antioxidant activity was evaluated by ABTS tests and the antibacterial activity was tested using the diffusion method. Yellow oils were obtained with yields ranging between 0.28 % and 3.60 %. Our results showed that essential oils of different plant parts were mainly composed by dillapiole (2.39 to 41.35 %), thymyl methyl ether (20.13 to 34.75 %), p-cymene (4.83 to 22.08 %) and γ-terpinene (22.54 to 43.29 %). Evaluation of antioxidant activity showed that the oils of flowers exhibited the most important antioxidant potential oils of flowers, leaves, seeds were the most active against Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus epidermidis, respectively. The essen...

Essential oils (EO) from fresh and dry aerial parts of Pituranthos chloranthus (Benth.) Hook and Pituranthos tortuosus (Coss.) Maire were isolated by hydrodistillation and analyzed by GC/MS. The main constituents of the EO obtained from fresh herb of P. chloranthus were found to be α-pinene, sabinene, cis-ocimene and myrcene. In dry biomass, a significant increase of the content of some compounds such as α-phellandrene, △,3-carene and β-phellandrene characterized the oil. Minor changes in the chemical composition of the P. tortuosus EOs obtained from fresh or dry herbs and the major constituents were found to be sabinene and myrcene with equilibrate amounts of α-pinene, p-cymene, cis-ocimene, limonene, trans-β-ocimene, γ-terpinene and cis-verbenol. The paper disc diffusion method was used to evaluate the antibacterial activity and results showed an important inhibitory effect of oils obtained from fresh herb against most tested bacteria.

Four flavones were isolated from dried leaves of Artemisia campestris L. 2',4',5,7-tetrahydroxy-5',6-dimethoxyflavone, eupatilin and dimethoxycentaureidin were reported for the first time in this species whereas cirsiliol was previously identified but it was isolated for the first time. Their structures were elucidated by spectroscopic methods, including 1D and 2D NMR experiments and mass spectrometry analysis. In addition, all isolated flavones were evaluated for their antioxidant, anti-inflammatory, anti-superoxide dismutase, anti-xanthine oxidase and cytotoxic activities. The results showed that all isolated compounds exhibited potent anti-xanthine oxidase activity with IC50 ranging from 3.3 to 6.8 µM, which was higher than that of the control compound allopurinol (8.2 ± 0.6 µM). In addition, cirsiliol was found to be the most cytotoxic against OVCAR-3, IGROV-1and HCT-116 cell lines at 15µM, with inhibition percentage values of 53.7, 48.8 and 40.9%, respectively. All compounds also showed weak to moderate anti-inflammatory and anti-superoxide dismutase activities.

Polyphenols are bioactive molecules exhibiting a lot of scientific attention due to their multiple biological activities. The present study aimed at assessing the phenolic content, antibacterial activity and antioxidant activity of the different organs of Crithmum maritimum (leaves, flowers, seeds and stems) cultivated in the south east of Tunisia. The analyzed organs exhibited different content of total polyphenol (17.11 ± 0.77 to 9.42 ± 0.24 mg GAE g -1 DW) flavonoids (7.06 ± 0.18to 3.71 ± 0.1 mg EC g –1 DW) and tannins (5.24 ± to 1.06 ± 0.77 mg CE g –1 DW). However, seeds extracts displayed the highest DPPH• scavenging ability with the lowest IC50 value (406 ± 11 μg/ml) and for antibacterial activity is showed that the diameter of the largest inhibition (13 mm) is recorded for the extrat from stems of C. maritimum vis a vis a gram negative bacterium Pseudomonas aeruginos. The smaller diameter of inhibition (6 mm) was recorded for extract from seeds against gram-positive bacteria: Staphyloccus ...

This study was conceived to examine the antimicrobial and antioxidant activities of four essential oil types extracted by hydrodistillation from the aerial parts of Artemisia herba-alba cultivated in southern Tunisia. The chemical composition was investigated using both capillary GC and GC/MS techniques. β-thujone, α-thujone, α-thujone/β-thujone and 1,8-cineole/camphor/α-thujone/β-thujone were respectively, the major components of these oil types. The antimicrobial activity of different oils was tested using the diffusion method and by determining the inhibition zone. The results showed that all examined oil types had great potential of antimicrobial activity against strains. In addition, antioxidant capacity was assessed by different in vitro tests and weak activity was found for these A. herba-alba oils.

The essential oils extracted by Clavenger apparatus from leaves of Rosmarinus officinalis cultivated in different areas in Djerba (Island in the southern of Tunisia) were evaluated for their chemical composition (GC and GC-MS methods), antioxidant (DPPH method) and antibacterial activities (agar-well diffusion method). GC-MS analysis revealed the presence of three chemotypes of oils: 1,8-cineole, 1,8-cineole/camphor/α-pinene/camphene and 1,8-cineole/camphor/α-pinene/ verbenone/borneol which was not previously detected in Tunisian Rosmarinus officinalis. The three chemtypes exhibited moderate antioxidant activity with an IC50 ranged from 4.186 mg/ml for chemotype I to 7.298 for chemotype II and showed strong to moderate antibacterial activity against the six bacterial strains tested with a MIC ranged from 0.156 to 1.25 mg/mL (Chemotype I and chemotype II) and from 1.25 to 5 mg/mL (chemotype III). This study showed that the essential oil extracted from Rosmarinus officinalis cultivated in Djerba ha...

Seedlings of Artemisia herba-alba Asso collected from Kirchaou area were transplanted in an experimental garden near the Institut des Regions Arides of Medenine (Tunisia). During three years, the aerial parts were harvested (three levels of cutting, 25%, 50%, and 75% of the plant), at full blossom and during the vegetative stage. The essential oil was isolated by hydrodistillation and its chemical composition was determined by GC (RI) and 13C-NMR. With respect to the quantity of vegetable material and the yield of hydrodistillation, it appears that the best results were obtained for plants cut at 50% of their height and during the full blossom. The chemical composition of the essential oil was dominated by b-thujone, a-thujone, 1,8-cineole, camphor and trans-sabinyl acetate, irrespective of the level of cutting and the period of harvest. It remains similar to htat of plants growing wild in the same area.

SUMMARYArtemisia herba-alba Asso has been successfully cultivated in the Tunisian arid zone. However, information regarding the effects of the harvest frequency on its biomass and essential oil yields is very limited. In this study, the effects of three different frequencies of harvesting the upper half of the A. herba-alba plant tuft were compared. The harvest treatments were: harvesting the same individual plants at the flowering stage annually; harvesting the same individual plants at the full vegetative growth stage annually and harvesting the same individual plants every six months. Statistical analyses indicated that all properties studied were affected by the harvest frequency. Essential oil yield, depended both on the dry biomass and its essential oil content, and was significantly higher from plants harvested annually at the flowering stage than the other two treatments. The composition of the β- and α-thujone-rich oils did not vary throughout the experimental period.

The leaf oil isolated by hydrodistillation from aerial parts of Artemisia campestris L. (Asteraceae) collected from four areas of the south of Tunisia (Bengardane, Benikhdache, Jerba and Tataouine) at three periods of the year 1998 (April, August and November) have been analyzed by GC and GC/MS. β-Pinene (24.0–49.8%) was found to be the main component of this oil. Monoterpene hydrocarbons were shown to be the major fraction (58.8–88.6%), and mainly composed of β-pinene (24.0–49.8%), α-pinene (5.9–12.5%), p-cymene (3.4–9.4%), limonene (4.9–9.3%), (Z)-β-ocimene (0.2–5.5%) and γ-terpinene (2.0–6.5%). Oxygen-containing monoterpenes represented less than 10% of the total oil and was found to mainly contain geranyl propionate (1.6–4.4%), α-terpineol (0.6–2.2%) and terpinen-4-ol (0.7–1.9%). Sesquiterpenes ranged from 5.0% to 29.8%. γ-Muurolene (0.3–5.4%) and ω-cadinene (0.2–2.4%) were the major sesquiterpene hydrocarbons whereas spathulenol (1.2–8.9%) and β-eudesmol (1.0–6.4%) were the main oxygen-conta...

The composition of the essential oil obtained by hydrodistillation from the aerial parts of several populations of Artemisia campestris L. (Asteraceae), collected from four areas of south-eastern of Tunisia (Bengardane, Benikhdache, Jerba and Tataouine), was analysed by GC–MS. Thirteen to fifteen components were identified in each sample, representing more than 95% of the total oil. All samples were dominated by the presence of β-pinene (24.2–27.9%), p-cymene (17.4–22.3%) and α-pinene (4.1–11.0%), representing more than 45% of the total oil. The distribution of other components in the different extracts was qualitatively and quantitatively irregular. The variability of the composition can be attributed to the climatic and geographical conditions among areas. Copyright © 2001 John Wiley & Sons, Ltd.

The intraspecific chemical variability of essential oils (50 samples) isolated from the aerial parts of Artemisia herba-alba Asso growing wild in the arid zone of Southeastern Tunisia was investigated. Analysis by GC (RI) and GC/MS allowed the identification of 54 essential oil components. The main compounds were β-thujone and α-thujone, followed by 1,8-cineole, camphor, chrysanthenone, trans-sabinyl acetate, trans-pinocarveol, and borneol. Chemometric analysis (k-means clustering and PCA) led to the partitioning into three groups. The composition of two thirds of the samples was dominated by α-thujone or β-thujone. Therefore, it could be expected that wild plants of A. herba-alba randomly harvested in the area of Kirchaou and transplanted by local farmers for the cultivation in arid zones of Southern Tunisia produce an essential oil belonging to the α-thujone/β-thujone chemotype and containing also 1,8-cineole, camphor, and trans-sabinyl acetate at appreciable amounts.

The essential oil of Artemisia campestris and the ethanol–water, hexane and water extracts of A. campestris and Thymelaea hirsuta collected in southern of Tunisia were investigated for their antioxidant (DPPH, ABTS and beta-carotene methods) and antitumor growth inhibition of human colon cancer HT-29 cells using MTT test activities. All the A. campestris extracts tested at high concentrations (100 μg/ml) showed activity ranging from 19.5% for essential oil to 64.4% of negative control growth for infusion extract, except the hexane extract. With T. hirsuta , all the extracts tested (hexane and ethanol–water), except the infusion extract, also exhibited antitumor activity (58.2% and 65.5% of control growth respectively). The ethanol–water and infusion extracts of A. campestris showed higher antioxidant activity, polyphenol and flavonoid contents than those of T. hirsuta. These results show that there is a positive correlation between the antitumor activity and the antioxidant activity, and of these two activities and with the levels of polyphenols and flavonoids. The essential oil and the other extracts of A. campestris, which exhibited significant antitumor activity against the HT-29 cells deserve further research into the chemoprevention and treatment of colon cancer.

Eight annual species growing wild in the southern of Tunisia (Diplotaxis simplex, Chrysanthemum coronarium, Matthiola longipetela, Erodium glaucophyllum, Reseda alba, Diplotaxis harra, Senecio gallicus and Papaver rhoeas) were evaluated for their mineral contents and phytochemical screening. The mineral analysis showed that calcium and potassium were the most concentrated minerals (1.21-3.60% and 0.36-3.20% respectively) followed by sodium (0.12-1.38%), magnesium (0.16-0.41%) and phosphorus (0.05-28%). The preliminary phytochemical screening revealed the absence of anthraquinones in all studied plants whereas alkaloids were only present in Papaver rhoeas. Senecio gallicus and Chrysanthemum coronarium were the only species that contained essential oils. All species were found to contain saponins, flavonoids and tannins with the exception of Erodium glaucophyllum and Papaver rhoeas. These results indicate that some of these species may be used as fodder plants for livestock due to their high contents of minerals but the presence of some secondary metabolites may reduce their palatability. In the other hand, these secondary metabolites could be the origin of the medicinal properties of these species.

The essential oil content of Artemisia herba-alba Asso decreased along the drying period from 2.5 % to 1.8 %. Conversely, the composition of the essential oil was not qualitatively affected by the drying process. The same principle components were found in all essential analyzed such as α-thujone (13.0 – 22.7 %), β-thujone (18.0 – 25.0 %), camphor (8.6 - 13 %), 1,8-cineole (7.1 – 9.4 %), chrysanthenone (6.7 – 10.9 %), terpinen-4-ol (3.4 – 4.7 %). Quantitatively, during the air-drying process, the content of some components decreased slightly such as α-thujone (from 22.7 to 15.9 %) and 1,8-cineole (from 9.4 to 7.1 %), while the amount of other compounds increased such as chrysanthenone (from 6.7 to 10.9 %), borneol (from 0.8 to 1.5 %), germacrene-D (from 1.0 to 2.4 %) and spathulenol (from 0.8 to 1.5 %). The chemical composition of the oil was more affected by oven-drying the plant material at 35°C. α-Thujone and β-thujone decreased to 13.0 %and 18.0 %respectively, while the percentage of camphor,...