Thesis Abstract

<p> In this study, the antihyperlipidemic and antioxidants activities of the extract and fractions of<br>Phaseolus vulgaris L. were evaluated. The crude extract (PVE) of dried pulverized plant material<br>was obtained by maceration in methylene chloride/methanol (11) while the solvent fractions<br>were obtained by successive solvent-solvent partition in separating funnel between the crude<br>extract suspended in aqueous medium and solvents of increasing polarity to obtain the n-hexane<br>fraction (PVHF), ethylacetate fraction (PVEF), and butanol fraction (PVBF) in that<br>order.Antihyperlipidemic effects of the extracts and fractions were investigated using acute, subacute<br>and chronic models. In all threemodels, treatment with (PVE) caused significantreduction<br>(P&lt;0.05) in the lipid profile parameters with the most significance seen in the sub acute study<br>where total cholesterol was decreased by 38.44%. Triglycerides level was significantly decreased<br>(P&lt;0.05) by 18.18% in the acute study model.Similarly, very low density lipoprotein (VLDLC)<br>and low density lipoprotein (LDL-C) wasrespectively decreased by 18.18% and 48.73% in the<br>acute antihyperlipidemia model. In contrast, high density lipoprotein (HDL-C) level was<br>significantly (P&lt;0.05) increased in the acute phase by 20.85%.In all study protocols involving<br>the various fraction there were significant increase(P&lt;0.05) in lipid profile. PVEF (400 mg/kg)<br>produced- the most significant reduction in total cholesterol level in the acute study with<br>percentage decrease of 22.10% compared to the control treatment. Triglycerides level was<br>similarly reduced by 21.59% and 15.91% at PVHF (200 mg/kg) and PVEF (200 mg/kg) with the<br>acute study.The sub-acute protocol showed significant decrease at PVBF 200 mg/kg percentage<br>decrease of 17.28%. VLDL-C level for the fraction study showed significant decrease (P&lt;0.05)<br>at PVHF 200 mg/kg and PVEF 200 mg/kg with percentage decrease of 21.59% and 15.91%<br>during the acute protocol, the sub-acute protocol showed significant decrease at PVBF 200<br>mg/kg percentage decrease of 17.28. LDL-C level for fraction extract study showed dose<br>dependent significance decrease (P&lt;0.05) seen at PVHF 100 mg/kg, PVEF100 mg/kg, and 200<br>mg/kg with percentage decrease of 47.19%, 41.62% and 53.39% respectively during the acute<br>protocol, Finally in the chronic protocol a significant decrease was seen with PVHF 200mg/kg,<br>PVEF 100 mg/kg, and PVBF 200 mg/kg with percentage decrease of 26.03%, 24.82% and<br>20.05% respectively. HDL-C level for extract study showed dose dependent significant increase<br>(P&lt;0.05) seen at PVHF 100 mg/kg, PVEF 100 mg/kg and 200 mg/kg with percentage increase<br>of 30.44%, 28.88% and 30.86%. DPPH reduction and nitric oxide scavenging assays were used<br>in the investigation of the extract and fractions for the in vitro antioxidant activities study, the<br>antioxidant activities of the extract and fractions were further determined in vivo in rats.<br>Antioxidant enzymes and factors such as catalase, glutathione peroxidase, and lipid peroxidation<br>activities were measured in carbon tetrachloride-treated rats treated with or without the extract<br>and fractions studies. The highest percentage reduction of DPPH was 80.61% seen with PVEF<br>and PVBF fraction at 400 mg/kg. The highest percentage reduction of nitric oxide was 75.86%<br>seen with PVHF at 200 mg/kg. The in vitro study showed significant increased (P&lt;0.05)<br>scavenging activity with the PVHF and PVEF having scavenging activity comparable with<br>ascorbic acid. In in-vivo antioxidant assay showed that the Lipid peroxidation levels estimated by<br>thiobarbituric acid reaction showed no significant (P&gt;0.05) increase or decrease in the serum<br>MDA of both the treated and untreated group, while in catalase activity estimation showed<br>significant (P&lt;0.05) increase was seen with PVE 100 mg/kg of 71.05%, Glutathione peroxidise<br>activity showed the most significant percentage (P&lt;0.05) increase of 76.19% for PVBF 100<br>mg/kg.The results of the study showed that the extracts and fractions of Phaseolus vulgaris<br>xiv<br>xiv<br>posses anti-hyperlipidemic and antioxidant with the PVEF showing better and more consistent<br>effects with all protocols used in the investigation. <br></p>

Thesis Overview

<p> 1.0. INTRODUCTION<br>A large volume of scientific research suggests that in situations of oxidative stress, reactive<br>oxygen species (ROS) are generated and a homeostatic environment between anti-oxidant and<br>oxidation is created. <br></p>