Jean Paul Wathelet

New study of the essential oil, mineral composition and antibacterial activity of Pistacia lentiscus L. from Eastern Morocco

The present study describes the chemical composition of essential oils of Pistacia lentiscus L., collected from different regions of Eastern Morocco. The essential oils were obtained by hydro-distillation of the areal parts and analyzed by gas chromatography and gas chromatography coupled to a mass spectrometry. The study was conducted to determine the phytochemistry and antibacterial activities of oil from P. lentiscus leaves against both bacteria using the disc diffusion method. For Gram-negative, Salmonella sp., Klebsiella, Escherichia coli, and Pseudomonas, and for Gram-positive, Staphylococcus aureus, and Streptococcus were used as test bacterial strains. In the end, we completed the previous study by determining the minor and major mineral contents of leaves of P. lentiscus. The yield of P. lentiscus oil ranged between 0.13 and 0.23xa0%, with the chemical composition changing from one region to another. The variations are important between plant populations. The major oil components of PLL oil from Taforalt and Saidia (humid climate) were limonene and α-pinene, while myrcene, β-caryophyllene were found to be the major components of Laayoune and Jerada oil (semi-arid climate). For the mineral composition of PLL, the results show that trace element profiles of leaves from different regions differed significantly; the highest levels of K, Mg, Fe, and Ca were found in leaves of all locations, while the leaves collected from the Jerada region had the highest content of mineral substrates. This work also attempts to contribute to the knowledge of the nutritional properties of this plant; the results will be investigated for the evaluation of dietary information.

Adsorption of essential oil components of Lavandula angustifolia on sodium modified bentonite from Nador (North-East Morocco)

The analysis of essential oil has basically one technical goal: to achieve the best possible separation performance by using the most effective, available and current technology of chromatography. The present work aimed to study the formulation created by the adsorption of active components of Lavandula angustifolia essential oil on sodium modified bentonite. Essential oils were obtained from dried leaves of L. angustifolia ; they were extracted by hydro distillation and were analyzed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography flame ionization detector ( GC-FID). The retention indices (RI) were calculated for each detected component. Besides, the characterization of the individual components making up the oils was performed with the use of a mass spectrometry (MS) library. The quantitative analysis was made by GC - FID . The identified components accounted for more than 95% for each essential oil. The results of these studies show that organic contaminant adsorption is dependent, to some degree, on solid-liquid ratio and the competition system of mixture. The adsorption amount of terpenics and the others components could be the results of many factors. The selectivity was affected by the abundance of each component in the crude essential dependent on the particle size fractions; the finer fractions adsorbed higher amounts. The selectivity of adsorption was affected by the polarity of terpenic components. Keywords: Clays, bentonite, essential oil, adsorption, Lavande angustifolia . African Journal of Biotechnology , Vol 13(31) 3413-3425

Efficacy of powdered maize cobs against the maize weevil Sitophilus zeamais (Coleoptera: Curculionidae) in stored maize in Senegal

Powdered maize cobs were tested as an alternative for pesticide use in stored maize. Five doses (2, 4, 6, 8 and 10 g/250 g seed) of powdered maize cobs applied at particle sizes of 1.4 and 0.4mm diameter were compared with actellic powder against Sitophilus zeamais Motschulsky for 120 days. Mortality and survival data showed that cob powders did not act as fumigant but exerted a potent inhibition of progeny on direct contact with S. zeamais adults. The particle size of powdered cobs had no effect on maize damage and losses. At doses equal to or higher than 6 g powdered maize cobs/250 g grain maize, i.e. 2.4% (w/w), damage to grain was < 5% and weight losses < 1%. The protection offered at the highest dose was comparable to the pesticide control. The use of powdered maize cobs is discussed as a natural alternative to synthetic pesticides for protection of maize against S. zeamais.

Essential Oil Composition of Ocimum basilicum L. and Ocimum gratissimum L. from Algeria

Abstract The constituents of essential oils isolated by hydrodistillation of the overground parts of Ocimum basilicum L. and Ocimum gratissimum L. from Algeria were examined by GC and GC-MS. A total of 46 and 43 components were identified accounting for 99.4 % and 97.7 % of O. basilicum and O. gratissimum oils, respectively. The oil of O. basilicum contained, as main components, linalool (44.7 %), linalyl acetate (14.0 %), 1,8-cineole (6.7 %), myrcene (5.6 %), α-terpineol (5.1 %), geranyl acetate (4.0 %), alloocimene (2.4 %), neryl acetate (2.4 %), elemol (2.1 %) and β-caryophyllene (1.3 %). Major compounds in the essential oil of O. gratissimum were eugenol (54.8 %), β-elemene (10.9 %), 1,8 cineole (4.1 %), α-humulene (3.8 %) linalool (2.1 %) and α-amorphene (2.1 %).

Chemical Composition of Volatile Oils from Algerian Nigella sativa L. seeds

Abstract The chemical composition of the volatiles obtained from the fixed oils of Nigella sativa L. seeds growing in Algeria was investigated by GC and GC/MS analysis. Two solvents were studied for extracting the oils, hexane and isopropanol. The composition of N. sativa seeds varieties having four location origins in Algeria, were determined. Alcohols and ketones formed the main proportion using the two solvents, respectively (hexane: 27.4–36.1%, isopropanol: 40.2–59.0%) and (hexane: 39.9–44.3%, isopropanol: 17.5–50.7%), among which thymoquinone and thymohydroqui-none were the predominant antioxidant compounds. The monoterpene hydrocarbons constitute relatively the lower fraction compared to the precedent chemical families, particularly by using the isopropanol solvent.

The Essential Oils of Origanum majorana L. and Origanum floribundum Munby in Algeria

Abstract The constituents of essential oils isolated by hydrodistillation of the overground parts of Origanum majorana and Origanum floribundum from Algeria were examined by GC and GC-MS. A total of thirty eight and thirty seven components were identified accounting for 93.3 % and 88.9 %, respectively, of the oils of O. majorana and O. floribundum. The oil of O. majorana (yield: 1.2 %) contained, as main components, β-caryophyllene (26.0 %), α-terpinolene (14.7 %), λ-terpinene (10.9 %) and sabinene (9.5 %). Major compounds in the volatile oil of O. floribundum (yield: 1.6 %) were λ-terpinene (34.1 %), p-cymene (27.6 %) and carvacrol (9.6 %).

CHEMICAL COMPOSITION AND PHYSICOCHEMICAL CHARACTERISTICS OF FIXED OILS FROM ALGERIAN Nigella sativa SEEDS

The fatty acids, sterols, and polyphenols from the fixed oils of Nigella sativa seeds originating from four locations were determined. The seeds contained respectively 30.63–34.27% and 25.66–32.77% of fixed oils using hexane and isopropyl alcohol in solvent extraction. Linoleic, oleic, and palmitic acids formed the main proportion using the two solvents, respectively: hexane 54.47–61.28%, isopropanol 56.98–67.30%; hexane 19.62–22.94%, isopropanol 18.85–21.96%, and hexane 11.17–13.60%, isopropanol 9.20–14.18%. Other minor unsaturated fatty acids were identified. Eight phytosterols were isolated and identified in the fixed oils by GC and GC/MS analysis, wherein β-sitosterol was the dominating compound that inhibits the absorption of dietary cholesterol, followed by stigmasterol, campesterol, and Δ5-avenasterol.