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) with 20% supplementation showing the highest decrease (38.70%). Triglyceride levels decreased significantly (p<0.05) across all the groups. The 5% AYB supplementation showed the highest decrease (35.63%) and 20% supplementation the lowest decrease (28.01%). Low density lipoprotein (LDL) levels of the rats significantly (p<0.05) decreased across the groups. The control group also showed 50.34% decrease in LDL but 10% AYB supplementation showed the highest decrease (61.29%). Serum high density lipoprotein (HDL) concentration increased significantly (p<0.05) after supplementation with AYB. The 20% AYB supplementation showed the highest percentage increase (22.85%) relative to the other groups. There were significant decreases in serum total cholesterol, LDL cholesterol, triglyceride and increase in HDL cholesterol for the groups with AYB supplementation.

1.1       Background of the study
1.2       Statement of the problem
1.3       Objectives of the study
1.3.1    General objectives
1.3.2    Specific objectives
1.4       Significance of the study

2.1       Hypercholesterolemia
2.2       Signs and symptoms of hypercholesterolemia
2.3       Causes of hypercholesterolemia
2.3.1    Diet
2.3.2    Genetics
2.4       Risk factors of hypercholesterolemia
2.5       Diagnosis
2.6       Diseases and conditions associated with hypercholesterolemia
2.6.1    Cardiovascular diseases
2.6.2    Obesity
2.6.3    Diabetes
2.6.4    High Blood pressure
2.7       Management of hypercholesterolemia
2.7.1    Diet
2.7.2 Dietary factors
2.7.3 Nutritional components
2.7.4 Specific foods
2.7.5 Additives and supplements
2.7.6 Dietary fibre
2.7.7 Dietary approaches
2.8 African Yam Beans (AYB)
2.8.1 Origin and distribution of AYB
2.8.2 Nutritional composition of AYB
2.8.3 AYB in diet related non communicable disease management
2.8.4 Constrains to the use of AYB
2.9 Phytochemicals and antinutrients
2.9.1 Phytate
2.9.2 Tannins
2.9.3 Saponins
2.9.4 Flavonoids
2.10 Proximate analysis
2.10.1 Protein
2.10.2 Fats

3.1 Sample collection
3.2 Sample preparation
3.3       Analytical procedures
3.3.1    Proximate analysis
3.3.2    Phytochemical analysis
3.4       Biological analysis
3.4.1    Animal and housing
3.4.2    Experimental design
3.4.3    Plasma lipid and lipoprotein analysis
3.5       Statistical analysis


5.1       Discussion
5.2       Conclusion
5.3       Recommendations

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). Cardiovascular disease (CVD) is a class of diseases that involve the heart or blood vessels (arteries and veins) (Maton, 1993). It refers to any disease that affects the cardiovascular system, principally cardiac disease, vascular diseases of the brain and kidney, and peripheral arterial disease (Kelly & Fuster, 2010). According to the World Health Organization, chronic diseases are responsible for 63% of all deaths in the world, with cardiovascular disease as the leading cause of death (WHO, 2011). An estimated 17.3 million people died from CVD’s in 2008. Over 80% of CVD deaths take place in low- and middle-income countries. By 2030, almost 23.6 million people will die from CVDs (WHO, 2011). There are many causes of cardiovascular disease but the most common are atherosclerosis and/or hypertension. The different types of cardiovascular disease include coronary heart disease (CHD), cardiomyopathy, hypertensive heart disease, heart failure, cor pulmonare, cardiac dysrhythmias, inflammatory heart disease (endocarditis, inflammatory cardiomegaly, and myocarditis), valvular heart disease, stroke or cerebrovascular accident, peripheral arterial disease. CVD typically involves the coronary arteries and thus is frequently termed coronary heart disease (CHD) or coronary artery disease (CAD). The risk factors of cardiovascular disease are in addition to high fat diet; age, gender, high blood pressure, high blood cholesterol levels, tobacco, smoking, excessive alcohol consumption, family history, obesity, lack of physical activity, psychosocial factors and diabetes mellitus (Kelly & Fuster, 2010).

Evidence shows that the Mediterranean diet improves cardiovascular outcomes (Walker & Reamy, 2009). The Mediterranean diet is made up of high olive oil consumption, high consumption of legumes, unrefined cereals, fruits, and vegetables, moderate consumption of dairy products, and moderate to high consumption of fish, low consumption of meat and meat products and moderate wine consumption. A 10-year study published in the Journal of American Medical Association (JAMA) found that adherence to a Mediterranean diet and healthful lifestyle was associated with more than a 50% lowering of early death rates (Knoops et al., 2004).

Legumes have benefits in terms of reduced risk of CHD. Legumes or dry beans have been shown to improve serum lipid profiles in patients with CHD (Anderson & Major, 2002; Bazzano, Thompson, Tees, Nguyen & Winham, 2009) and a growing body of evidence supports the positive effects dietary legume consumption confers on health, particularly in relation to risk of CHD. Epidemiological studies support the cardio protective effects of legumes as part of a healthy diet. In particular, one study examined the relationship between beans consumption and occurrence of CVD and reported that 1 serving per day of beans was associated with a 38% lower risk of myocardial infarction (Kabagambe, Baylin, Ruiz-Narvarez, Siles & Campos, 2005). A second study by Bazzano, He & Ogden (2001) reported that individuals consuming legumes at least four times per week had a 22% lower risk of heart disease than individuals consuming legumes less than once per week. Majority of legume studies have examined the relationship between soybeans and heart disease. Some studies using navy beans and chickpeas have been conducted. In an early report, Anderson and Major (2002) demonstrated that consumption of navy beans in tomato sauce (baked beans) for 21 days decreased serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) concentrations in hypercholesterolemic men (Anderson, Gustafson, Spencer, Tetyen & Bryant, 1990). A research by Finley, Burrel, and Reeves (2007) reported that pinto beans consumption is also favourable. Cowpea commonly consumed in Nigeria has been linked to present significant reductions in plasma total cholesterol and non-HDL cholesterol (Frota, Mendonca, Saldiva, Cruz, & Areas, 2008). As Liu (2006) reported, diets with low glycemic index are associated with a reduced risk for the development of diabetes mellitus, obesity and cardiovascular disease.

All legumes contain phytochemicals which play metabolic roles in humans who frequently consume these foods. Phytochemicals, also referred to as phytonutrients, are found in fruits, vegetables, whole grains, legumes, beans, herbs, spices, nuts, and seeds and are classified according to their chemical structures and functional properties. Phytochemicals are non-nutritive plant chemicals that have protective or disease preventive properties. There are many phytochemicals and each works differently. Presence of phytochemical components such as phytohemagglutinins, tannins, phytic acid, saponins, protease inhibitors, oligosaccharides and phytoestrogens in food legumes has both health benefits and adverse effects. These are some possible action; antioxidant, hormonal action, stimulation of enzymes, interference with DNA replication, anti-bacterial effect and physical actions. These.....

For more Home Science, Nutrition & Dietetics Projects click here
Item Type: Project Material  |  Attribute: 86 pages  |  Chapters: 1-5
Format: MS Word  |  Price: N3,000  |  Delivery: Within 30Mins.


No comments:

Post a Comment

Select Your Department

Featured Post

Reporting and discussing your findings

This page deals with the central part of the thesis, where you present the data that forms the basis of your investigation, shaped by the...