ABSTRACT
Daucus carota (carrot) seed is used medicinally in the treatment and management of diabetes mellitus, in whichoxidative stress and hyperlipidemia are associated complications. The study evaluated the antioxidant andantihyperlipidemic effects of aqueous seed extract of D. carota aqueous extract (AQEDCS) in triton ×100-inducedhyperlipidemic mice. The in vitro antioxidant activities of the extract (0.2–1.0 mg/ml) were evaluated using totalantioxidant capacity, 2,2-diphenyl-1-picrylhydrazyl, nitric oxide, and ferric ion scavenging. In vivo antioxidantand antihyperlipidemic properties of AQEDCS extract were evaluated using triton ×100-induced oxidative stressand hyperlipidemia in mice. AQEDCS contains alkaloids, tannins, phenols, and produced significant antioxidanteffects in vitro compared to Vitamin C. AQEDCS significantly (P < 0.05) decreased levels of plasma cholesterol,triacylglycerol, low-density lipoprotein, coronary artery, cardiac, and atherogenic indices and increased circulatinghigh-density lipoprotein levels when compared to untreated hyperlipidemic mice. AQEDCS significantly (P < 0.05)decreased the level of malondialdehyde compared to untreated hyperlipidemic mice. AQEDCS and simvastatindecreased (P < 0.05) reduced glutathione concentration in plasma, with no difference (P > 0.05) in the liver of micecompared to untreated hyperlipidemic mice. Similarly, no significant difference (P > 0.05) was observed in plasmanitrite levels, superoxide dismutase, and glutathione S-transferase except in AQEDCS mice that received 100 mg/kgbody weight dose of AQEDCS extract when compared with non-induced control. The results indicated that AQEDCSpossesses antioxidant and antihyperlipidemic effects, and could complement antioxidant defense system in vivoduring oxidative stress as well as prevent further complications that could arise from hyperlipidemia during its usagefor diabetes mellitus treatments.
ABSTRACT
<p><b>OBJECTIVE</b>Phytochemical constituents as well as antimalarial and toxicity potentials of the methanolic extract of the husk fibre of Dwarf Red variety of Cocos nucifera were evaluated in this study.</p><p><b>METHODS</b>The dried powdered husk fibre was exhaustively extracted with hexane, ethyl acetate and methanol successively and the methanolic extract was screened for flavonoids, phenolics, tannins, alkaloids, steroids, triterpenes, phlobatannins, anthraquinones and glycosides. A 4-day suppressive antimalarial test was carried out using Plasmodium berghei NK65-infected mice, to which the extract was administered at doses of 31.25, 62.5, 125, 250 and 500 mg/kg body weight (BW). Toxicity of the extract was evaluated in rats using selected hematological parameters and organ function indices after orally administering doses of 25, 50 and 100 mg/kg BW for 14 d.</p><p><b>RESULTS</b>Phytochemical analysis revealed the presence of alkaloids, tannins, phenolics, saponins, glycosides, steroids and anthraquinones in the extract. Moreover, the extract reduced parasitemia by 39.2% and 45.8% at doses of 250 and 500 mg/kg BW respectively on day 8 post-inoculation. Various hematological parameters evaluated were not significantly altered (P>0.05) at all doses of the extract, except red blood cell count which was significantly elevated (P<0.05) at 100 mg/kg BW. The extract significantly increased (P<0.05) urea, creatinine, cholesterol, high-density lipoprotein-cholesterol and bilirubin concentrations in the serum as well as atherogenic index, while it reduced albumin concentration significantly (P<0.05) at higher doses compared to the controls. Alanine aminotransferase activity was reduced in the liver and heart significantly (P<0.05) but was increased in the serum significantly (P<0.05) at higher doses of the extract compared to the controls.</p><p><b>CONCLUSION</b>The results suggest that methanolic extract of the Dwarf red variety has partial antimalarial activity at higher doses, but is capable of impairing normal kidney and liver function as well as predisposing subjects to cardiovascular diseases.</p>