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Objectives: Daniellia oliveri Rolfe is a well-known plant of Fabaceae family whose previous phytochemical and pharmacological studies led to the identification of triterpenoid, phenol, anthraquinone oxalate with antioxidant, antibacterial and antifungal activities. This study aimed to investigate chemical constituents and evaluate the antimicrobial potency of the root of D. oliveri. Methods: The methanol extract of the root barks of D. oliveri was subjected to silica gel chromatographic separation. The structures of the isolated compounds (1 - 9) were determined by analyzing their spectrometric and spectroscopic spectra. Single-crystal-Xray analysis was used to establish the absolute skeletal structure of compound 1. Crude extract, fractions and compounds were investigated against four bacteria vis Pseudomonas aeruginosa 27853, Escherichia coli 5, Staphylococcus aureus 25923 and Streptococcus sp. 9619 and, two yeast vis Candida albicans 14053 and Candida tropicalis 018 using broth microdilution method. Results: The phytochemical prospection of the methanol extract of D. oliveri allowed the isolation of a naturally crystallized diterpenoid type furolabdane: polyalthic acid 1, as well as eight amorphous compounds (2 - 9). Among the tested samples, the crude extract, fractions and compounds selectively showed inhibitory effects against the tested microorganisms with MIC values ranging from 4 to 1024 μg/mL. Fraction D1 and compounds 1, 4, 7, 8 and 9 exhibited the broadest antimicrobial effects among fractions and compounds while D5 and compound 1 showed the best activity with MIC values of 16 and 4 μg/mL respectively against E. coli which appeared to be the most sensitive strain. Conclusion: Polyaltic acid (1) showed the best activity with significant MIC value of 4 μg/mL identical to that of ceftazidine against E. coli. The MIC values of the active compounds 1, 4 and 7 are comparable to those of ceftazidime. Then, these compounds from natural origin, could serve as markers in the standardization of Daniellia plant as phytomedicine. [ABSTRACT FROM AUTHOR]

Preservative properties of essential oils from Aframomum citratum, Aframomum daniellii, Piper capense and Monodora myristica are well known in agri-food. In the current work, we study the possibility of using these oils in cosmetic creams as preservatives. Essential oils were obtained from powdered seed by hydrodistillation using a Clevenger-type apparatus. Their chemical compositions were determined using Gas Chromatography/Mass Spectrometry (GC/MS). Their cytotoxic activities were assayed against human intestinal (Caco-2) and epidermal (HaCaT). Briggs-Rauscher test and peroxide index were used to study the evolution of the antioxidant activity of essential oil-based cream submitted to accelerate aging process. Major component of the essential oil from the seeds of A. citratum was geraniol (97.6 %) while the essential oil of the seed of A. daniellii was rich in eucalyptol (51.5 %), α-terpineol (12.5 %) and β-pinene (8.5 %). Majors components of the essential oil from P. capense were β-pinene (38.1 %), germacrene D (12.3 %), trans-β-caryophyllene (11.3 %) and α-pinene (9.0 %) while the essential oil of seed of M. myristica was predominantly constituted of α-phellandrene (77.8 %). Essential oils of A. citratum and P. capense showed low cytotoxicity on the tested cells. M. myristica demonstrated a low cytotoxicity on epidermal cell lines HaCaT and no cytotoxicity on Caco-2 cell lines. No cytotoxicity was recorded with A. daniellii. The four essential oils in cosmetic cream preserved it from oxidation during accelerated aging process. This study provided evidence for possible utilization of Aframomum citratum, Aframomum daniellii, Piper capense and Monodora myristica essential oils in the prevention of oxidative damages in cosmetic creams. [ABSTRACT FROM AUTHOR]