Purpose: To explore the hypotensive activity and chemical composition of
Moringa oleifera
Lam
(Moringaceae) roots.
Methods: The fresh roots of
M. oleifera was cut into small pieces and successively extracted with
petroleum ether (PE) and dichloromethane (DC). PE extract was further divided into MRP and MRP -1.
DC extract showed a thick mass during evaporation which was separated as MRDC - IN. The mother
liquor left was divided into MRDC and MRDC -1. All residues were analyzed by gas chromatographymass
spectroscopy (GC-MS) using ZB-5 column. Identification of each extract and fraction was based
on comparison of their retention indices (RI), by co-injecting authentic compounds, as well as by
comparing literature data available in NIST Standard Reference Database. Hypotensive activity was
determined on urethane-anesthetized normotensive Sprague Dawly rats.
Results: Petroleum ether (MRP) and dichloromethane (MRDC) extracts of
M. oleifera roots showed
50.06 ± 3.48 and 48.16 ± 1.79 % fall in mean arterial blood pressure (MABP), respectively, at a dose of
30 mg/kg (p < 0.01 and p < 0.05, respectively) compared with control. GC-MS analysis of MRP and
MRDC extracts and fractions resulted in the identification of seventy four (74) compounds. Methyl
hexadecanoate (
7, 20.3 %) , stigmastan - 3, 5, diene (
24, 19.32 %), methyl 14-hydroxy-5-
tetradecenoate (
9, 19.22 %), 1 , 11 diphenyl undecane (
47, 18.78 %) and cyclopentanyl hexadecane
(
39, 14.44 %) were the major constituents among the various hydrocarbons, fatty acids, esters,
alcohols, aldehydes, isothiocyanate, aromatics, steroids, terphenyl and sulphur-containing compounds.
Conclusion: The findings reveal the hypotensive potential of
M. oleifera roots and the presence of
specific hydrocarbons, fatty acid esters, thioureides, steroids and isothiocyanates in active fractions.
Further study is required to determine the suitability of the plant as an antihypertensive remedy.
