Essential Oil’s Chemical Composition and Pharmacological Properties

Essential oil, sent by nature, is a complex mixture of volatile secondary metabolites. Its composition varies along with many parameters that can lead to misunderstanding of its wonderful pharmacological property. In fact, from post-harvest treatment to the compound’s identification through extraction approaches, the original chemotype of essential oils can be misdescribed. The pharmacological potentials of these oils are well known in the traditional system since time immemorial. Nowadays, some chemotypes of these oils had shown the effect against WHO’s top 10 killer diseases. But the misuses of these essential oils are in part due to the lack of robust and easy analysis strategy that can allow the quality of the essential oils

Antioxidant and Antifungal Activities of Cocoa Butter (Theobroma cacao), Essential Oil of Syzygium aromaticum and a Combination of Both Extracts against Three Dermatophytes

To contribute in the research of better drugs against dermatophytosis, we evaluated the antioxidant and antidermatophytic activities of cocoa butter, cloves essential oil, and a mixture of both extracts. The cocoa butter was obtained by boiling the cocoa paste. The essential oil extracted by hydrodistillation was chemically analysed by gas chromatography and gas chromatography coupled with mass spectrometry. The antioxidant activity was determined using the DPPH scavenging method, and  the antidermatophytic activity was evaluated using the agar dilution method. The essential oil, majoritary constituated by eugenol (87.62%), β-caryophyllene (5.88%), and β-bisabolene (4.41%), had an antiradical power (4.22 x 10-2) higher than that of BHT (4.00 x 10-3), like the cocoa butter and essential oil mixture (6.06 x 10-3). The essential oil was more active than the griseofulvin: it was fungicidal at 400 ppm against Trichophyton rubrum, and at 900 ppm against Microsporum gypseumand Trichophyton tonsurans. The cocoa butter activity was low, but the mixture with the essential oil had an important activity with inhibitory percentages of 78.69 %, 88.27 %, 91.20% against T. rubrum (at 400 ppm), T. tonsurans(at 900 ppm)and M. gypseum (at 900 ppm)respectively. Cloves essential oil and the mixture with cocoa butter can be used to formulate new drugs against dermatophytes.

Essential oil of Xylopia aethiopica from Cameroon: Chemical composition, antiradical and in vitro antifungal activity against some mycotoxigenic fungi

The aim of this work was to evaluate the chemical composition, antiradical activity and antifungal activity of Xylopia aethiopica essential oil from Cameroon against five mycotoxigenic fungal strains responsible for the biodegradation of foodstuffs. The Clevenger apparatus was used for the extraction of essential oil from dried fruits, which was subsequently analyzed by CG and CG/ MS for determination of its chemical profile. The incorporation method and the method using the DPPH radical were used respectively for the in vitro evaluation of the antifungal and antioxidant activity of the essential oil of X. aethiopica. The yield of essential oil was 4.2% (v/w). The main components of Xylopia aethiopica essential oil were β-pinene (32.16 ± 3.69%), β-phellandrene (10.71 ± 3.05%), Z-γ-bisabolene (10.07 ± 2.61%) and α-pinene (7.39 ± 1.69%). The essential oil of X. aethiopica showed a low antiradical activity (SC50 = 594.58 ± 57.37 μg/mL) as compared to that of BHT (SC50 = 65.03 ± 0.99 μg/mL). The essential oil has a good antifungal activity against Aspergillus niger and Fusarium oxysporium with a minimum inhibitory concentration of 3000 ppm for the two fungal strains and a minimum fungicidal concentration of 3000 and 4000 ppm respectively. The essential oil of X. aethiopica did not exert a fungicidal effect against A. flavus, A. fumigatus and A. versicolor, for which the MIC was 4000 ppm. The most resistant fungal strain was Aspergillus fumigatus. This study shows that the essential oil of X. aethiopica has a real potential as an antifungal agent for controlling fungal growth on foodstuffs. Keywords: Essential oil, Xylopia aethiopica, Chemical composition, Antioxidant activity, Antifungal activit

Effet de la cercosporiose à

Introduction. Les dommages provoqués par la cercosporiose des agrumes, dus à Phaeoramularia angolensis, sont à l'origine de pertes de récolte ou d'écarts de tri pouvant varier entre (50 et 100) % de la production. Or tous les organes attaqués par la maladie - pétales des fleurs, feuilles et surtout peau des fruits - renferment des huiles essentielles à haute valeur marchande. Une étude a été réalisée pour connaître l'influence des attaques de cette maladie sur le rendement d'extraction et la qualité des huiles essentielles de peau d'orange. Matériels et méthodes. L'extraction d'huile essentielle a été réalisée par hydrodistillation à partir de fruits récoltés à maturité et les extraits ont été analysés par chromatographie en phase gazeuse afin de déterminer leur composition chimique. Résultats et discussion. Le rendement d'extraction des huiles essentielles a diminué en fonction de la gravité des attaques (jusqu'à 40 % de baisse). Cette baisse n'a été significative que lorsque les attaques dépassaient deux lésions par fruit. Les extraits obtenus de fruits attaqués à divers degrés ont présenté quelques variations quantitatives de leurs constituants. Une diminution de certains composés dans les fruits malades s'est accompagnée d'une augmentation de leur forme oxygénée. L'augmentation de la quantité globale d'aldéhydes a été observée dans les fruits malades, ce qui pourrait se traduire par une amélioration de la qualité des huiles essentielles. Mais, en même temps, les oxydes caractéristiques de la dégradation de ces huiles essentielles ont augmenté. Conclusion. Ce travail qui doit être approfondi a permis d'acquérir de premières données sur les pertes de rendement et l'évolution de la composition des huiles essentielles de peau de fruits pouvant être attribuées aux attaques de la cercosporiose

Acaricidal activity of five essential oils of Ocimum species on Rhipicephalus (Boophilus) microplus larvae.

International audienceThe aim of this study was to evaluate the acaricidal activity on the cattle tick Rhipicephalus (Boophilus) microplus of essential oils from three Ocimum species. Acaricidal activity of five essential oils extracted from Ocimum gratissimum L. (three samples), O. urticaefolium Roth, and O. canum Sims was evaluated on 14- to 21-day-old Rhipicephalus microplus tick larvae using larval packet test bioassay. These essential oils were analyzed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC/MS) showing great variations of their chemical compositions according to the botanical species and even within the O. gratissimum species; the acaricidal activity of their main compounds was also evaluated. The essential oils of O. urticaefolium and O. gratissimum collected in Cameroon were the most efficient with respective LC50 values of 0.90 and 0.98 %. The two essential oils obtained from O. gratissimum collected in New Caledonia were partially active at a dilution of 5 % while the essential oil of O. canum collected in Cameroon showed no acaricidal activity. The chemical analysis shows five different profiles. Whereas the essential oils of O. urticaefolium from Cameroon and O. gratissimum from New Caledonia contain high amounts of eugenol (33.0 and 22.3–61.0 %, respectively), 1,8-cineole was the main component of the oil of an O. canum sample from Cameroon (70.2 %); the samples of O. gratissimum oils from New Caledonia are also characterized by their high content of (Z)-β-ocimene (17.1–49.8 %) while the essential oil of O. gratissimum collected in Cameroon is mainly constituted by two p-menthane derivatives: thymol (30.5 %) and γ-terpinene (33.0 %). Moreover, the essential oil of O. urticaefolium showed the presence of elemicin (18.1 %) as original compound. The tests achieved with the main compounds confirmed the acaricidal activity of eugenol and thymol with residual activity until 0.50 and 1 %, respectively, and revealed the acaricidal property of elemicin, which was the most efficient compound with 100 % of acaricidal activity at a dilution of 0.25 % and could be a valuable acaricide for the control of the cattle tick R. microplus

Antioxidant and antiinflammatory potential of essential oils of some Zanthoxylum (Rutaceae) of Cameroon

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Correlation between chemical composition and antifungal properties of essential oils of callistemon rigidus and callistemon citrinus of Cameroon against Phaeoramularia angolensis

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Antioxidant and antiinflammatory potential of essential oils of some Zanthoxylum (Rutaceae) of Cameroon

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Antifungal activity of the essential oil of Cymbopogan citratus (Poaceae) against Phaeoramularia angolensis

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Comparaison des propriétés antiradicalaires et antiinflammatoires des huiles essentielles de Citrus reticula var. Madagascar et Citrus sinensis var. Casagrande du Cameroun.

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