PROXIMATE AND PHYTOCHEMICAL COMPOSITION OF AFRICAN YAM BEAN (Sphenostylis stenocarpa) AND ITS EFFECT ON THE LIPID PROFILE OF HYPERCHOLESTEROLEMIC RATS ()
ABSTRACT
The study examined the proximate and phytochemical (saponins, tannins, phytate and flavonoid) composition of roasted cream coloured African yam bean (AYB) flour and the lipid profile of hypercholesterolemic rats fed diets supplemented with African yam bean. Different diets were formulated using the AYB flour. Group 1 consisted of the normal control rats (untreated rats), group 2 consisted of the hypercholesterolemic group of rats that were untreated. Groups 3-6 consisted of rats fed rat chow with 5%, 10%, 15% and 20% AYB flour supplementation, respectively. Proximate analysis was done using AOAC methods. Phytochemical and biochemical analyses were done in duplicates using standard methods. The proximate analysis showed that AYB flour contain 4.94% moisture, 27.66% protein, 4.29% fat, 3.66% ash, 9.57% crude fibre and 49.88% carbohydrate. The phytochemical analysis showed 0.77mg/100g saponins, 42.07mg/100g tannins, 9.08mg/100g phytate and 1.01mg/100g flavonoid. Total cholesterol level for the different supplementation groups showed significant decrease (p<0 .05=”” 10=”” 20=”” 50.34=”” 5=”” across=”” after=”” all=”” also=”” and=”” ayb.=”” ayb=”” but=”” cholesterol=”” concentration=”” control=”” decrease=”” decreased=”” decreases=”” density=”” for=”” group=”” groups.=”” groups=”” hdl=”” high=”” highest=”” in=”” increase=”” increased=”” ldl=”” levels=”” lipoprotein=”” low=”” lowest=”” of=”” other=”” p=”” percentage=”” rats=”” relative=”” serum=”” showed=”” showing=”” significant=”” significantly=”” span=”” supplementation.=”” supplementation=”” the=”” there=”” to=”” total=”” triglyceride=”” were=”” with=””>
CHAPTER ONE
INTRODUCTION
1.1 Background to the Study
Hypercholesterolemia is the presence of high levels of cholesterol in the blood, and is a form of “hyperlipidemia” (elevated levels of lipids in the blood) and “hyperlipoproteinemia” (elevated levels of lipoproteins in the blood) (Durrington, 2003).This is a major risk factor for cardiovascular disease especially coronary heart disease (Mudabmbi & Rajagopal, 2007). Cholesterol is the main sterol found in body tissues. Since cholesterol is insoluble in water, it is transported in the blood plasma bound to protein particles (lipoproteins). Lipoproteins are classified by their density; very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), low density lipoprotein (LDL) and high density lipoprotein (HDL) (Biggerstaff & Wooten, 2004). All the lipoproteins carry cholesterol, but elevated levels of the lipoproteins other than HDL (termed non-HDL cholesterol), particularly LDL-cholesterol is associated with an increased risk of atherosclerosis and coronary heart disease (Carmena, Duriez & Fruchart, 2004). Dietary intervention trials have shown that the reduction of serum total and LDL cholesterol concentration is beneficial for the reduction of coronary atherosclerosis in people with or without coronary heart disease (Gould, 1992; Ornish, 1998).
PROXIMATE AND PHYTOCHEMICAL COMPOSITION OF AFRICAN YAM BEAN (Sphenostylis stenocarpa) AND ITS EFFECT ON THE LIPID PROFILE OF HYPERCHOLESTEROLEMIC RATS ()