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Essential oils obtained by hydrodistillation of seeds, pericarps, leaves and rhizomes of Aframomum dalzielii, A. letestuianum and A. pruinosum grown in Cameroon were analyzed by GC-FID and GC-MS. The seed oils of the three species were characterized by a high content of (E)-(R)-nerolidol (>88.0 %), which was fully characterized by NMR spectroscopy and chiral GC analysis. The main constituents of the pericarp and rhizome oils were monoterpene hydrocarbons, mainly -pinene (0.8%-22.9%) and sabinene (29.0%-42.3%), along with 1,8-cineole (4.5%-23.7%); leaf oils were characterized by sesquiterpenes, namely (E)-β-caryophyllene (18.4%-82.4%) and caryophyllene oxide (4.5%-23.7%). The antibacterial activities of these essential oils and of nine pure compounds (sabinene, -pinene, 1,8-cineole, linalool, racemic (E)-nerolidol, (E)-(R)-nerolidol, (E)-β-caryophyllene, α-humulene and caryophyllene oxide) were assessed against Micrococcus luteus and Escherichia coli. The strongest activities were observed against E. coli. The seed essential oils and their major component, (E)-(R)-nerolidol, exhibited the lowest MIC values (0.19-0.39 µL/mL), justifying their traditional use and their potential application as natural food preservatives.

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The ability of water and sodium bicarbonate solution in producing debittering cocoa bean for immediate consumption as ready to cook food and the applicability of empirical Peleg model in order to interpret the sorption data is evaluated in this study. Fermented cocoa beans were soaked and/or boiled in water and in 2% sodium bicarbonate solution with a weight to volume ratio of 1:10. Cocoa beans were withdrawn at each interval over a 6-h time period and moisture and minerals (calcium, magnesium, phosphorus and potassium) content analyzed using standard analytical methods. Bitterness was measured by sensory analysis. Peleg model was used to transform the sorption data into the mathematical equation and Peleg parameters K 1 , K 2 and M e calculated. It has been found that boiling in water and sodium bicarbonate (2%) significantly reduces the bitterness of cocoa beans. Kinetic curves of water absorption express the characteristic shape with a fast water absorption rate at the beginning of the process follow by a decreasing rate as the equilibrium moisture is reached. Mineral desorption curves exhibited unusual pattern depending on the mineral under consideration. Application of sorption data demonstrates a predictive capacity of the Peleg model as judged by the regression coefficients. Boiling cocoa beans for 50 min in 2% sodium bicarbonate and 30 min in boiling water can be considered as optimal for debittering cocoa beans in order to give them palatable option to be integrated in nutrition and in none medicinal therapeutics in Cameroon.

In order to provide an effective alternative for efficient management of dermatophytosis, we evaluate in vitro the antioxidant and antiradical potentials of the essential oil of the dry flower buds of Syzygium aromaticum and its antidermatophytic activity against Epidermophyton floccosum and Trichophyton soudanense, For this purpose, the essential oil was obtained by hydrodistillation through a Clevenger apparatus and the antioxidant and antiradical potentials were evaluated by the ferric reducing antioxidant power (FRAP) and the trapping of the ABTS•+ radical methods, respectively. The evaluation of the antidermatophytic activity was made by the agar incorporation method. The results showed that the essential oil reduced ferric iron (Fe3+) to ferrous iron (Fe2+) in a more significant manner than BHT (reference antioxidant). Moreover, the antiradical power of the essential oil was twice greater than that of BHT. Furthermore, the essential oil inhibited the mycelial growth of the two dermatophytes, with 500 ppm and 1000 ppm of minimal inhibitory concentrations against Epidermophyton floccosum and Trichophyton soudanense, respectively. This activity was greater than that of griseofulvin whose minimal inhibitory concentration was greater than 4000 ppm against both studied germs. These findings show that, withon the framework of safeguarding human lives and protecting the environment, the essential oil from the dry flower buds of Syzygium aromaticum appeared as reliable alternative for the treatment of dermatophytosis caused by Epidermophyton floccosum and Trichophyton soudanense. Our results lay scientific foundation toward the promotion and development of Cameroonian biodiversity in treatments of dermatophytosis.

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