Chemical Composition and in vitro Antibacterial Activity of the Essential Oils of the Leaves, Resin and Stem-Barks of Dacryodes edulis (G. Don) H. J Lam growing in Cameroon on Diarrhea Associated Strains

Abstract

The aim of this work was to determine the chemical profile and assess in vitro the antibacterial activity of the leaves, resin and stem-barks of Dacryodes edulis. The essential oils were analyzed simultaneously by Gas Chromatography and Gas Chromatography coupled to Mass Spectrometry. Agar diffusion well and microdilution methods were used to assay the antibacterial activity. The resin essential oil contained p-cymene (30.32%), α-thujene (28.58%), α-phellandrene (27.14%) and β-phellandrene (10.16%) as the main components; the stembarks essential oil had as abundant components p-cymene (35.14%), trans-carveol (22.60%), α-thujene (14.86%), β-phellandrene (8.65%) and β-elemene (5.22%). The leaves essential oil was distinct with elemol (29.22%), caryophyllene oxide (15.26%), trans-carveol (11.80%) and spathulenol (6.28%) as major components. The leaves essential oil was the most active with MIC and MBC value of 18.75 mg/mL on B. cereus; the most susceptible strain. The stem-barks essential oil had a MIC of 50 mg/mL and MBC of 100 mg/mL on all the strains meanwhile the resin essential oil had a bacteriostatic effect at 200 mg/mL. Based on these results, it emanates that the essential oils of D. edulis represent a potential source of antibacterial substances.

Antibacterial and Antioxidant Activities of Dacryodes edulis Methanolic Leaf Extract

“…Shigella sp. had MIC of 0.27 mg/mL which was far lower than the value obtained by Riwon et al [21] for this microorganism.…”

“…with MIC value of 2.19 mg/mL as mpared to 18.75 mg/mL reported by Riwom [21] for the same microorganism. The highest activity as determined by MIC was P. aeruginosa and sp.…”

“…The highest activity as determined by MIC was P. aeruginosa and sp. had MIC of 0.27 mg/mL which was far lower than the value [21] for this…”

“…The value of the minimum inhibitory concentrations is usually and adequate guide for the treatment of most infections [15]. Methanolic leaf extract showed higher activity against aureus with MIC value of 2.19 mg/mL as compared to 18.75 mg/mL reported by Riwom et al [21] for the same microorganism. The highest activity as determined by MIC was observed against Shigella sp., P. aeruginosa K. pneumoniae.…”

Untitled

“…The analysis of Z. officinale essential oil was conducted at the Max Mousseron Institute of Biomolecules, Montpellier National Higher School of Chemistry, France, by Gas-Chromatography coupling Mass Spectrometry (GC-MS) as described previously (Riwom et al, 2015). The oil components were identified based on their relative retention indices with either those of authentic samples or with published data in the literature (Adams, 2012).…”