PHYTOCHEMICAL ANALYSIS OF SELECTED TOMATO PRODUCTS
TABLE
OF CONTENT
Title
page-----------------------------------------------------------
Approval
page------------------------------------------------------
Dedication-----------------------------------------------------------
Acknowlegdement---------------------------------------------------
Abstract---------------------------------------------------------------
Table of
contents----------------------------------------------------
List of
tables---------------------------------------------------------
List of
figures-------------------------------------------------------
Abbreviations--------------------------------------------------------
CHAPTER ONE
1.0 Introduction-------------------------------------------------
1.1 Objectives of
the Study-------------------------------------
CHAPTER TWO
2.0
Literature
Review---------------------------------------------
2.1 Importance of
Phytochemicals-----------------------------
2.1.1 Mechanism
of Action of Tomato Phytochemicals-------
2.1.2 Importance
of Tomatoes------------------------------------
2.2 Structure of
Vitamin C and its Activity------------------
2.2.1 Biosynthesis
and species-synthetic ability--------------
2.2.2 Absorption,
Transport and Disposal---------------------
2.2.3 Deficiency-----------------------------------------------------
2.2.4 Physiological
functions in mammals---------------------
2.2.5 Daily
requirement-----------------------------------------
2.2.6 Therapeutic
uses--------------------------------------------
2.2.7 Adverse
effects-----------------------------------------------
2.3 Structure of
Beta Carotene and its Activity-------------
2.3.1 Previtamin
A activity----------------------------------------
2.3.2 Symmetric
and Asymmetric Cleavage-------------------
2.3.3 Sources
in Diet----------------------------------------------
2.3.4 Side
Effects---------------------------------------------------
2.3.5 Beta
Carotene and lung cancer in smokers-------------
2.3.6 Uses based on Scientific Evidence-----------------------
2.4 Structure of
Lycopene and Its Chemical Activity-----
2.4.1 Bioavailability
of Lycopene--------------------------------
2.4.2 Digestion
and absorption of Lycopene-------------------
2.4.3 Roles of
Lycopene in Human Health---------------------
2.5 Structure of
Polyphenol and its activity------------------
2.5.1 Classification
and Nomenclature-------------------------
2.5.2Potential Health Benefits-----------------------------------
CHAPTER THREE
3.0 Materials and
Methods-------------------------------------
3.1 Equipments/Apparatus------------------------------------
3.2 Procurement of
Raw Materials----------------------------
3.3 Study
Design-------------------------------------------------
3.4 Sample
Processing-------------------------------------------
3.5 Chemical
Analysis of Samples-----------------------------
3.5.1Vitamin C content determination-------------------------
3.5.2Beta-carotene content
Determination--------------------
3.5.3 Lycopene
Content Determination ------------------------
CHAPTER FOUR
4.0 Results and discussion-------------------------------------
CHAPTER FIVE
5.0 Conclusion----------------------------------------------------
Reference------------------------------------------------------------
CHAPTER
ONE
1.0
INTRODUCTION
Intake
of tomato and tomato based-products contributes to the absorption of a wide range
of carotenoids in human serum and tissues. The prominent carotenoid in tomatoes
is lycopene, a pigment principally responsible for the deep-red colour of
tomato fruits and tomato products. Fruits and vegetables contain in excess of
40 carotenoids that are routinely absorbed and metabolized by humans (Khachik, 2014).
Tomatoes
and tomato products are now being investigated for their potential role in
prostate cancer prevention and therapy. This review summarizes the in vitro and
invivo evidence as well as the molecular data that show the anticarcinogenic
potential of tomatoes. Raw and
processed tomatoes are among the most commonly consumed vegetables. They are
rich in the phytochemicals, carotenoids and polyphenols. Lycopene and quercetin
are the most abundant carotenoids and flavonols respectively. Canned tomato sauce
is the primary source of lycopene whereas the tomato skin is enriched with
flavonols. Most epidemiological studies suggest that the consumption of
tomatoes and the products in associated with a reduced prostate cancer risk.
The health professionals follows-up study found that men who consumed 2 to 4
servings of raw tomatoes per week had a more than 20% reduction in prostate
cancer risk compared to men who did not consume tomatoes. High lycopene plasma
concentrations were associated with a low incidence of prostate cancer and
aggressive prostate cancer in rested case-control study with the physician’s
health study. Invitro data show that the compounds found in tomatoes are potent
anticarcinogens. Cancer cell growth is inhibited by the polyphenols quercetin,
kaempferol and naringerin in a dose dependent manner. These compounds do not
have cytotoxic effect. In a rat model of prostate cancer, tomato powder into
but not lycopene intake by itself reduced prostate cancer related mortality.
This suggests that the compounds in tomatoes have an additive influence on
prostate cancer. Lycopenes exist as either the cis or trans isomer. The
half-life of lycopene is approximately 10 to 14 days, so it remains in the body
during washout period. The trans isomer dominates in tomatoes, between the cis
isomer dominates in serum and tissues and during a washout period. Thus, recent
intake of lycopenes is reflected in blood concentrations whereas long-term
exposure is determined in the tissues.
Lycopene
is a bioactive carotenoid found in many red fruits and vegetables, such as tomatoes,
watermelon, pink grapefruits etc. Different fruits, vegetable and their products
contain different concentrations of lycopene. This natural red pigment is
synthesized exclusive by plants and microorganisms (fungi, bacteria and algae).
It facilitates the absorption of light during photosynthesis and also provides protection
against photosensitization (Adam et al., 2016) Animals including human being,
cannot synthesize lycopene therefore, they obtain lycopene exclusively from
diet (Tapiero et al. 2014; Omoni and Aluko, 2015).
Although,
tomato contain a lower concentration of nutrients compared to other
commercially grow fruits species, they are a major source of lycopene. Lycopene
comprises 83% of the total pigment present in tomatoes (Shi et al., 1990). Therefore,
the amount of lycopene present in tomatoes other fruits and vegetables vary
with variety, degree of ripeness and other dimatic conditions and agricultural
practices.
The
fraction of vitamin C in the diet that is absorbed and the rate at which the
excess is eliminated from the body vary strongly with the dose. Large, randomized
clinical trials on the effects of high doses on the general population have not
been conducted. Venturi suggested that the antioxidant action of ascorbic acid
developed first in the plant kingdom when, about 500 million years ago (mya),
plants began to adapt to antioxidant mineral deficient fresh waters of
estuaries. Ascorbic acid or vitamin C is a common enzymatic cofactor in mammals
used in the synthesis of collagen. Ascorbate is a powerful reducing agent
capable of rapidly scavenging a number of reactive oxygen species (ROS).
Freshwater fishes also require dietary vitamin C in their diet or they will get
scurvy. The most widely recognized symptoms of vitamin C deficiency in fishes
are scoliosis, lordosis and dark skin coloration.
The
name “carotene” was first coined in the early 19th century by the
scientist Wachenroder after he crystallized this compound from carrot roots.
Beta-carotene is a member of the carotenoids, which are highly pigmented (red,
orange, yellow), fat-soluble compounds naturally present in many fruits,
grains, oils and vegetables (green plants, carrots, sweet potatoes, squash,
spinach, apricots, and green peppers). Alpha, beta and gamma carotene are
considered provitamins because they can be converted to active vitamin A. The
carotenes possess antioxidant properties. Vitamin A serves several biological
functions including involvement in the synthesis of certain glycoproteins.
Commercially available beta-carotene produced synthetically or from palm oil,
algae, or fungi. Beta-carotene is converted to retinol, which is essential for
vision and is subsequently converted to retinoic acid, which is used for
processes involving growth and cell differentiation.
1.1 Objectives of the study
The
main objective of this project is to do a comparative analysis (quantitative
analysis) on phytochemicals present in tomatoes and some selected tomato
products (canned tomato) sold in any common market in Nigeria.
CHAPTER
TWO
2.0 LITERATURE REVIEW
Tomato, solanum lycopersicum, is one
of the most important vegetable crops of solanaceae, grown all over the world. Tomato
is thought to have had its center of origin in western South American. The
tomato never tables, was introduced into Africa by the European merchants and
their road into Nigeria garden is credited to early European settle in the
country.
Tomatoes are annuals, which grow to
70-200 cm in height. Although when young, plants are erect, as they mature they
are unable to bear their own light and fall on the ground ad thus becoming
prostrate. Stems and leaves are covered in numerous short hairs and when
bruised emit a very distinctive odour. The leaves are very large and compound,
coarsely arise from leaf and contain from 4-12 flowers which are hermaphrodite
with a superior ovary. The corolla which has 6 lobes is usually yellow and the
stamens (usually 6) form distinct cone which in many varieties cover the tops
of the stigma ensuring a high degree of self pollination.