ABSTRACT

Anti-hyperlipidemic potential of extracts (aqueous, 70% methanol, 70% ethanol and

70%, acetone) of Vitexdoniana leaves, stem bark and root bark on poloxamer 407

induced hyperlipidemic and normal rats was investigated. Phytochemical screening of the

extracts revealed the presence of flavonoids, saponins, cardiac glycosides, alkaloids and

tannins in the leaves, stem bark and root bark. The average total polyphenol contents of

the leaves ethanol (36.11±3.13mg/g gallic acid) and methanol (35.75±1.72mg/g gallic

acid) extracts were significantly (p<0.05) higher when compared with that of acetone and

aqueous extracts. The IC50of the leaves ethanol extract (0.227mg/ml) was lowerthan that

ofstem bark ethanol extract (0.236mg/ml) and root ethanol extract (0.561mg/ml).

Screening the extracts for the most potent anti-hyperlipidemicactivityreveals that

ethanolic extracts of root bark and leaveshas the highest percentage reduction of total

cholesterol (51.98%) and triacylglycerol (50.75%) respectively. The most abundant

phytochemical in the most potent extract is flavonoid (4.605±0.077%) in the leaves and

the least is tanins (0.035±0.008%) in the root bark extract. The LD50 of both leaves and

stem bark was greater than 5000mg/kg body weight and that of root bark was 948.68

mg/kg body weight. Hyperlipidemic control rats significantly (p<0.05) increased total

Cholesterol    (TC),     Triacylglycerol     (TAG),     Low    density    lipoprotein     (LDL-c)

andsignificantly (p<0.05) decreased High density lipoprotein (HDL-c) compared to other

groups.Atherogenic risk factor of all induced treated rats shows a significant (p<0.05)

lower levels of LDL-c/HDL-c, Log (TAG/HDL-c) and significant (p<0.05) higher level

of HDL-c /TC ratio. There was no significant (p>0.05) change between normal control

rats and normal treated rats in lipid profile parameters and atherogenic indices. The level

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