Variations in composition and antioxidant activity of Tunisian Pistacia lentiscusL. leaf essential oil

In this study, the composition and antioxidant activity of Pistacia lentiscus L. leaf essential oil (EO) from four Tunisian localities were investigated. The EO yields (%, w/w) of P. lentiscus leaf were 0.009% in Oued El Bir, 0.02% in Jebel Mansour, 0.007% in Siliana and 0.01% in Tabarka. The main compounds of Oued El Bir EO were terpinene-4-ol (41.24%) and α-terpineol (7.31%), whereas those of Jebel Mansour were α-pinene (9.48%), limonene (19.11%) and α-phellandrene (3.20%). In Siliana samples, terpinene-4-ol (23.32%), β-caryophyllene (22.62%) and α-terpineol (7.12%) were the main compounds. For P. lentiscus L. from Tabarka, α-terpineol (9.79%) and β-caryophyllene (38.33%) were the major constituents. Three chemotypes of P. lentiscus EO were identified for the first time in Tunisia. P. lentiscus EOs were also screened for their antioxidant activities. The 1,1-diphenyl-2-picrylhydrazyl assay gives an IC50 range value of 60–110 μg/mL for all the samples studied. EOs from different Tunisian localities showed lower β-carotene bleaching activity than butylated hydroxytoluene and butylated hydroxyanisol. P. lentiscus EO presents a very low capacity to chelate ferrous irons (IC50 = 80.8–104 μg/mL) and no metal chelating activity was recorded

Chemical Composition and Antioxidant and Antimicrobial Activities of Wormwood ( Artemisia absinthium

The aim of this study was to determine the chemical variability of wormwood extracts as affected by the growing region. Antioxidant and antimicrobial activities were also investigated. The essential oil composition variability of A. absinthium L. aerial parts collected from four different Tunisian regions was assessed by gas chromatography (GC/FID) and by gas chromatography mass spectrometry (GC/MS). In addition, total polyphenols, flavonoids, and condensed tannins as well as antioxidant, antibacterial, and antifungal activities of methanolic extract and essential oils were undertaken. Chromatographic analysis of wormwood essential oils showed the predominance of monoterpene hydrocarbons represented mainly by chamazulene. RP-HPLC analysis of wormwood methanolic extract revealed the predominance of phenolic acids. Antiradical activity was region-dependant and the methanolic extract of Bou Salem region has the strongest activity (CI50=9.38±0.82 µg/mL). Concerning the reducing power, the methanolic extract of Bou Salem, Jérissa, and Boukornine regions was more active than the positive control. Obtained results of antimicrobial activities showed that wormwood essential oil is endowed with important antibacterial activity which was strongly related to the organoleptic quality of oil which appeared strongly region-dependant. A. absinthium L. EOs investigated are quite interesting from a pharmaceutical standpoint because of their biological activities

Chemical composition and antioxidant activity of the coriander cake obtained by extrusion

This study was designed to examine the effect of operating conditions on essential oil composition and antioxidant activity of coriander cakes. Twenty-nine components were determined in essential oils, which were mostly alcohol monoterpenes. The highest essential oil yields (0.11%) were obtained by the nozzle diameter of 5 mm. The main components of cake essential oil linalool, gamma-terpinene, geranyl acetate, linalyl acetate and camphor showed significant variations with different nozzle diameter. The total phenol contents and condensed flavonoid contents varied between different nozzle diameters; the highest values obtained of small diameters (5 and 6 mm). Significant differences were also found in total tannin contents among different nozzle diameters. The total phenol contents decreased significantly (p < 0.05) when increased the nozzle diameter to 9 mm and reached 9.11 mg GAE/g. The screening of antioxidant activity of the different coriander cakes using the di(phenyl)-(2,4,6-trinitrophenyl) iminoazanium radical (DPPH) assay showed an appreciable reduction of the stable radical DPPH, although small nozzle diameter was the most efficient method with an IC50 reached of 55 mu g/ml as compared with bigger diameter (IC50 = 88 mu g/ml). All the extracts had lower beta-carotene bleaching activity than that of synthetic antioxidant BHA and BHT. Coriander cake extracts presented a very low reducing power ability (EC50 approximate to 700 mu g/ml) compared to ascorbic acid (EC50= 40 mu g/ml)

Insecticidal and Synergistic Activities of Two Essential Oils from Pistacia lentiscus and Mentha pulegium Against the Green Peach Aphid Myzus persicae

Chemical composition of two essential oils (EOs) extracted from Mentha pulegium and Pistacia lentiscus was investigated. Volatile compounds were characterized. Major ones were pulegone (45.89%), cis-menthone (23.25 %) and trans-menthone (14.73 %) for M. pulegium and α-pinene (28.57%), β-myrcene (21.03%) and L-limonene (6.97%) for P. lentiscus. Then, the insecticidal and synergistic activities of the EOs were studied against Myzus persicae. The results showed that both EOs were toxic against the target pest. Aphid mortality caused by M. pulegium and P. lentiscus Eos was 86 ± 11.4 and 76 ± 11.4%, respectively. LC50 of the latest EO was lower than that of P. lentiscus with 596 and 876 ppm, respectively. In addition, no synergism was observed when both oils were mixed and used against the same aphid. Interestingly, there are no differences between toxicity of both EOs and that of the chemical insecticide leading to 70 ± 10% mortality. This study suggested that the EOs have a great potential to be used in agriculture against M. persicae

Fumigant toxicity of <em>Pistacia lentiscus</em> essential oil against <em>Tribolium castaneum</em> and <em>Lasioderma serricorne</em>

International audienceThis study reports fumigant toxicity of Pistacia lentiscus L. (Anacardiacae) essential oil against 1-7 day-old adults of Tribolium castaneum (Herbst) and Lasioderma serricorne (F.). The chemical composition of the essential oil was assessed via GC and GC-MS. Alpha-phellandrene (3.20%), alpha-pinene (9.48%) and limonene (19.11%) were the major compounds. The mortality of adults was tested in different concentrations ranging from 114 to 1023 mu l/l air and different exposure times. Significant differences in insect mortality were observed within insect species, oil concentrations and exposure time. The fumigant toxicity potential of P. lentiscus on L. serricorne was greater (LC50= 8.44 mu l/l, LC95=43.68 mu l/l) than on T. castaneum (LC50 = 28.03 mu l/l, LC95 = 63.46 mu l/l). Moreover, the median lethal time values (LT50) were respectively 18.58 and 41.05 hours. The results suggested that P. lentiscus essential oil may have potential as a control agent against these two stored product beetles

Composition and insecticidal activity of essential oil from Pistacia lentiscus L. against Ectomyelois ceratoniae Zeller and Ephestia kuehniella Zeller (Lepidoptera: Pyralidae)

International audienceThis study reports investigations on the chemical constituents and fumigant toxicity of Pistacia lentiscus L. (Anacardiaceae) essential oil against two major stored-date insects, carob moth Ectomyelois ceratoniae Zeller and Mediterranean flour moth Ephestia kuehniella Zeller. Results showed that P. lentiscus essential oil contained terpinene-4-ol (23.32%), alpha-terpineol (7.12%) and beta-caryophyllene (22.62%) as major compounds. Fumigant toxicity tests showed that P. lentiscus oil was more toxic to E. kuehniella (LC50 = 1.84 mu l/l, LC95 = 5.14 mu l/l) than E. ceratoniae (LC50 = 3.29 mu l/l, LC95 = 14.24 mu l/l). The fecundity and hatching rate of both insects decreased with increases in concentration or exposure time to the oil. At 136 mu l/l air, fecundities and hatching rates were respectively 35 eggs/female and 42.86% for E. ceratoniae and 78 eggs/female and 29.49% for E. kuehniella. (C) 2010 Published by Elsevier Ltd

Phenological stage effect on phenolic composition and repellent potential of Mentha pulegium against Tribolium castaneum and Lasioderma serricorne

Objective: To elucidate for the first time the phenological stage effect on polyphenol, flavonoid and proanthocyanidin contents of pennyroyal (Mentha pulegium) as well as their antioxidant capacities and insecticidal potentials against Tribolium castaneum and Lasioderma serricorne. Methods: Crude methanol extracts from pennyroyal (Mentha pulegium) aerial parts were evaluated for their antiradical, reducing power activities and repellent potentials against selected coleopteran insects during different phenological stages. Results: Phenolic contents of pennyroyal aerial parts and their antioxidant effects were significantly dependent on maturity stage of the plant. The maximum of phenol production was reached during the full flowering stage. Apigenin was the major phenol in Mentha pulegium with an amount of 6.01 mg/g of dry vegetable matter during this period. Nevertheless, at fructification stage, the highest antioxidant activity was not related to high phenolic content. The repulsive effect of pennyroyal extract showed that Lasioderma serricorne was more susceptible to pennyroyal extract than Tribolium castaneum with corresponding median repellent dose values of 0.124 and 0.006 mg/mL respectively. Moreover, great differences in insect repulsion depending on extract concentrations, exposure time and developmental stage was observed. For the lowest concentration (0.125 mg/mL), the repellent effect against Tribolium reached its maximum (90%) during the fructification stage (after 24 h of exposure) while this repellent effect was 80% during the vegetative stage. Conclusions: Due to the strong insecticidal potential of pennyroyal extracts, this study highlights the therapeutic properties of this plant and encourages its use as a safer, environmental-friendly and efficient insecticide in food industry

Chemical Composition and Antioxidant and Antimicrobial Activities of Wormwood (Artemisia absinthium L.) Essential Oils and Phenolics

The aim of this study was to determine the chemical variability of wormwood extracts as affected by the growing region. Antioxidant and antimicrobial activities were also investigated. The essential oil composition variability of A. absinthium L. aerial parts collected from four different Tunisian regions was assessed by gas chromatography (GC/FID) and by gas chromatography mass spectrometry (GC/MS). In addition, total polyphenols, flavonoids, and condensed tannins as well as antioxidant, antibacterial, and antifungal activities of methanolic extract and essential oils were undertaken. Chromatographic analysis of wormwood essential oils showed the predominance of monoterpene hydrocarbons represented mainly by chamazulene. RP-HPLC analysis of wormwood methanolic extract revealed the predominance of phenolic acids. Antiradical activity was region-dependant and the methanolic extract of Bou Salem region has the strongest activity (CI50=9.38±0.82 µg/mL). Concerning the reducing power, the methanolic extract of Bou Salem, Jérissa, and Boukornine regions was more active than the positive control. Obtained results of antimicrobial activities showed that wormwood essential oil is endowed with important antibacterial activity which was strongly related to the organoleptic quality of oil which appeared strongly region-dependant. A. absinthium L. EOs investigated are quite interesting from a pharmaceutical standpoint because of their biological activities