Chemical Composition and Antimicrobial Potential of Essential Oils of Leaf and Stem Bark of Haematostaphis barteri Hook. f. (Anacardiaceae)

Abstract

Haematostaphis barteri Hook. f. is one of the aromatic plants for which there is no information on the essential oil composition. Hydrodistillation of leaf and stem bark of H. barteri essential oils were characterized using gas chromatography-mass spectrometry. Antimicrobial activity of the essential oils were carried out using 14 pathogens. The leaf essential oils of H. barteri were dominated by ar-curcumene (6.47- 12.73 %), β-sesquiphellandrene (3.91-7.14 %), α-zingiberene (3.40-7.11 %), β-bisabolene (3.74-6.73 %), (E)- caryophyllene (3.01-6.45 %) and fatty acids, oleic acid (12.04-34.64 %), palmitic acid (5.40-11.76 %) and linoleic acid (3.52-9.32 %). The stem bark oils were dominated by (E)-caryophyllene (14.56-19.32 %), α-humulene 16.99-16.64 %), caryophyllene oxide (6.03-7.31 %), δ-cadinene (2.49-9.37 %), humulene epoxide II (2.37-5.24 %), α- copaene (0.90-6.87 %). Kaurenal (9.06 %), 13-epi-manoyl oxide (8.12 %), (Z)-caryophyllene (5.93 %), and pentadecanal (4.52 %) were present in the stem bark of Kano essential oil but not present in the Kaduna oil. The essential oils (leaf and bark) demonstrated a broad spectrum of antimicrobial activities against 14 microorganisms with minimum inhibitory concentration (MIC) ranging from 78.1 to 1250 μg/mL; strongly active against Staphylococcus epidermidis (78.1 μg/mL). moderately active against Pseudomonas aeruginosa (156.3 μg/mL), weakly active against Candida albicans (312.5 μg/mL) for the leaf, while the stem barks were moderately active against Microsporum gypseum (156.3 μg/mL). The study shows that the essential oils of H. barteri possess promising antimicrobial activities.