Isolation and Structural Elucidation of Antimicrobial Molecules from Crinum ornatum (Aiton) Rhizome of Dutsin-Ma

Abstract

Crinum ornatum is a well-known traditional herb used used traditionally to treat various diseases including wounds, sores, vomiting, ear-aches, urinary tract infection, coughs and cold, renal and hepatic conditions, sexually transmitted diseases and backaches. The rhizomes of C. ornatum were collected, identified, air-dried and pulverized and subjected to cold extraction using hexane, dichloromethane (DCM), ethyl acetate (EtOAc) and methanol (MeOH) respectively. Antimicrobial activity of the extracts was determined using standard antimicrobial tests with Staphylococcus aureus, Salmonella typhi, Baccilus subtilis and Pseudomonas aeruginosa as test microorganisms. The most active extract was thereafter subjected to Gas chromatography Mass Spectrometry (GCMS) analysis, the Structural elucidation of the isolated molecule was performed using advanced spectroscopic techniques, including nuclear magnetic resonance (NMR), Fourier transform infrared (FTIR), Results of the antimicrobial activity test of the extracts showed appreciable antimicrobial activity against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella typhi (with MIC value ranging from 200 mg/ml to 25 mg/ml). The results demonstrated significant inhibitory effects, highlighting the potential of the compound as an antimicrobial agent. GCMS analysis identified 45 compounds in the most active (DCM) extract. Out of these, eight (8) compounds were most abundant (revealed >5% peak areas on GC chromatogram). These are: n-hexanedecanoic acid, hexadecanoic acid ethyl ester, 9,12-octadecadienoic acid (Z,Z),oleic acid, linoleic acid ethyl ester, ethyl oleate, squalene and tetrapentacontane. Antibacterial activity exhibited by the plant could be ascribed to the presence of the major phytocompounds in the plant and this provides scientific proof of some of ethnomedicinal uses of Crinum ornatum rhizome.