Volatile Phytochemical Compositions of Diodella sarmentosa Leaf and its Total Dehydrogenase Inhibitory Potential

doi.org/10.26538/tjnpr/v5i10.23

Abstract

In southern Nigeria, Diodella sarmentosa leaf is traditionally used in the treatment of various microbial infections. This work, therefore, aimed to establish the science behind the traditional use of the ethanol leaf extract of the plant for the treatment of microbial infections. Volatile organic compounds in the ethanol leaf extract of the plant were assessed using gas chromatography equipped with mass spectrometry (GC-MS). The activity of the extract on selected microorganisms and, their total dehydrogenase enzyme were assayed. Various volatile compounds were revealed by the GC-MS analysis with the major constituents being squalene (29.50%), Phytol (24.68%), 3-Pentadecyl-phenol (18.58%), 3-Methyl-1-butanol Isopentyl alcohol (9.09%), and Hexadecanoic acid (7.78%). The antimicrobial activity of the extract was first determined on six selected gram-negative (Salmonella typhi and Escherichia coli), gram positive bacteria (Bacillus subtilis and Staphylococcus aureus) and fungi (Candida albicans and Pennicilium spp) isolates. Bacillus subtilis, Candidas spp and Penicillium spp recorded higher zones of inhibition than the others. As a result, further studies of the extract effect on the dehydrogenase activity of these three most sensitive microorganisms were studied. The activity of the enzyme from Candidas spp, Penicillium spp, and Bacillus subtilis was progressively inhibited at increasing extract concentrations from 0 to 2000 mg/mL; and the threshold extract inhibitory concentrations (IC50) were 275 mg/mL, 322 mg/mL, and 411 mg/mL, respectively. From the findings, it can be concluded that the ethanol leaf extract of Diodella samentosa which is rich in antimicrobial volatile organic compounds inhibited microbial dehydrogenase activity.