Abstract

Studies were carried out to determine the effects of heating on the vitamin A and C content of a green leafy vegetable known as Pterocapus Mildbraedii. The samples of Pterocapus Mildbraedii leaves were boiled at different intervals (5 mins, 10 mins and 15 mins) guided and its extract was sequeezed.

The vitamin C content was measured through titrimetric methods. The vitamin C levels of Pterocarpus Milbraedii was found to be 73.92 ± 0.2mg/100g, while Vitamin A content was measured through the spectrophotometic method (with us-vis spectrophotometer).

The vitamin A levels of Pterocarpus mildbraedii was found to be 1.89 ± 0.04mg/100g. The vitamin C content of Pterocarpus mildbraedii reduced drastically after each time period during heating while vitamin A had little effect during the heating periods of the leaves.

This is because vitamin C is water soluble so it dissolves into the water and is lost via evaporation, while vitamin A being immiscible water, is not easily lost during heating.

Table of Content

Title page
Certification
Dedication
Acknowledgement
Abstract
Table of content

CHAPTER ONE
1.0 Introduction
1.1 Literature review
1.2 Pterocarpus mildbraedii
1.3 Common names
1.4 Classification
1.5 Description/Features
1.6 Cultivation
1.7 Propagation
1.8 Distribution
1.9 Nutritional value
1.10 Edible uses
1.11 Medicinal uses
1.12 Other uses
1.13 Storage
1.14 Side effects
1.15 Life span
1.16 Vitamin A
1.17 Beta-carotene
1.18 Importance/Effectiveness of Beta-carotene
1.19 Mode of actions
1.20 Interactions with medications
1.21 Interactions with food
1.22 Vitamin C
1.23 Biological significance
1.24 Absorption, Transportation and Excretion
1.25 Deficiency
1.26 Role in mammals
1.27 Role in plants
1.28 Testing for ascorbate levels in the body
1.29 Adverse effects
1.30 Heating/cooking effects in vitamin c
1.31 Other nutrients contained in Pterocarpus mildbraedii

CHAPTER TWO
2.0 Materials and methods
2.1 Experimental materials and equipment
2.2 Experimental chemicals
2.3 Sample collection
2.5. Principle of test
2.5. Sampling preparation
2.6 Preparation of specific molarities of the reagents needed.
2.6.1 Iodine solution
2.6.2 Starch indicator solution
2.7 Titration
2.8 Spectrophotometric determination of vitamin A
2.8.1 Procedure

CHAPTER THREE
3.0 Results

CHAPTER FOUR
4.0 Discussion and Conclusion
References
Appendix

Introduction

Vegetables form an integral part of meals of people all over Nigeria and across. Invariably, vegetables present a rich source of vitamins, minerals, fibre and protein. The selection of a particular vegetable for inclusion in the diet depends on the a number of factors such as nutrient composition, texture and price (Eyo Es et al., 1983). There are some less commonly used and inexpensive leafy vegetables whose nutritive potentials have not yet been adequately studied. One of such is the leaf of Pterocarpus mildbraedii.

Pterocarpus mildbraedii (local names: Ora, Igbo; Mkpa or mkpafere, Efik/Ibibio) thrives mainly in forest environment (Olorode O, 1984) the mature plant can attain a height of about twenty four meters. The leaves possess a glabrous common stalk, 10-20cm long, usually with five to nine leaflets in alternate but sometimes opposite arrangement. The upper leaflets are rather elongated abruptly acuminate and round at the base whereas the lower leaflets are more ovate (Keay RWJ et al, 1964). The leaves are light green in colour when young but becomes deep green upon maturity.

In some parts of Eastern Nigeria, the young and tender leaves of this plant are traditionally used as vegetable in the preparation of soups. Despite the rising cost of highly cherished food items, caused by the general inflationary trend in the country, the market price of some less popular food such as the edible leaves of Pterocarpus mildraedii have remained fairly stable and within the reach of a large segment of the population.

Vitamin A can be found in two principal forms on foods:
Retinol, the form of vitamin A absorbed when eating animal food sources, is a yellow, fat-soluble substance. Since the pure alcohol form is unstable, the vitamin is found in tissues in a form of retinyl ester, it is also commercially produced retinyl acetate or palmitate (Meschino health, 2012).

The second form is the carotene, alpha-carotene, beta-carotene, gamma carotene; and the xanthophyll beta cryptoxanthin (all of which contain beta-ionone rings), but no other carotenoids, function and provitamin A in herbivores and omnivore animals, which possess the enzyme beta carotene 15, 15-dioxygenase which cleaves beta-carotene in the intestinal mucosa and converts it to retinal. (Deman, John 1999).

Vitamin C or L-ascorbic acid, or simply ascorbate (the anion of ascorbic acid) is an essential nutrient for humans and certain other animal species. Vitamin C refers to a number of vitamers that have vitamin C activity in animals, including ascorbic acid and its salts and some oxidized forms of the molecule like dehydroascorbic acid. Ascorbate and ascorbic acid are both naturally present in the body when either of these is introduced into cells, since the forms interconvert according to PH. Deficiency of this vitamin causes the disease scurry in humans (Higdon J, 2006).

The Effect of Heating on the Vitamin A and C Content of Pterocarpus Mildbraedii Leaves (Oha Leaves)

Key Features

Table of Content

Introduction