Isolation, Characterisation and In Silico Toxicity Evaluations of Thiocarbamates, Isothiocyanates, Nitrile, Glucosinolate and Lipids from Moringa oleifera Lam. Seed

Abstract

The phytochemical composition of medicinal plants is responsible for theethnopharmacological applications. These phytochemicals vary in plants of same species planted invarious geographical locations. The seed of Moringa oleifera Lam., a widely consumed multi-medicinalplant was examined for the bioactive phytochemicals. With the aid of Nuclear Magnetic Resonance ( 1HNMR/13C-NMR) spectrometer, Electrospray Ionisation Mass Spectrometry (ESI-MS) and FourierTransform Infrared (FT-IR) spectroscopy, the phytochemical investigation of the seed of M. oleiferaafforded nine compounds which included niazimicin 1, niazidin 2, glucomoringin isothiocyanate 3,niazinin acetate 4, niazinin triacetate 5, niazirinin 6, glucotropaeolin 7, triolein 8, trivaccenin 9. TheGas Chromatography-Mass Spectrometry (GC-MS) analysis of a major oily fraction revealed thepresence of additional ten compounds which include oleic acid (major), 13-docosenoic acid, stearicacid, p-hydroxybenzyl cyanide, α -l-rhamnopyranose and other fatty acids/esters. This is the firstaccount of a fully acetylated niazinin (a 4-(2’,3',4’-O-triacetyl-α-L-rhamnosyloxy)benzylisothiocyanate) 5 from Moringa oleifera seed. The in silico toxicity evaluation indicated that most ofthe isolated compounds are either immunotoxic, carcinogenic or mutagenic. The result thus obtainedcould serve a basis for the pharmacological and toxicological evaluation and profiling of the seed. Theresult further implied the need for dosage regulation of the consumption of the seed.