ABSTRACT
This work was carried out to investigate the chemical properties of
the water extract of zobo (Hibiscus sabdariffa) drink using the modern
atomic absorption spectrophotometer. Zobo drink is a popular drink in
the Nigeria, especially in the northern part of Nigeria. The result of
the analysis indicated that the drink is high in vital mineral nutrients
required for the healthy growth by humans and for the proper metabolic
processes to be adequately maintained. Zobo drink is high, as indicated
in the result, in iron – a major component of the human haemoglobin,
when compared with other leaf like the popular vegetable leaf known as
awa (Piper methysticum).
TABLE OF CONTENT
Title page
Approval page
Dedication page
Acknowledgement
List of tables
Table of contents
Abstract
CHAPTER ONE: Introduction
1.1 Suggestions for further research
1.2 Objective of study
CHAPTER TWO: Literature Review
2.0 Scientific Classification of roselle (hibiscus sabdariffa).
2.1 Effect on smooth muscle
2.2 Effect on blood pressure
2.3 Anticancer and antioxidant activity
2.4 Anticholesterol effects
2.5 Hibiscus sabdariffa plant profile
2.5.1 Constituents of hibiscus sabdariffa
2.5.2 Herbal medicine and plants
2.5.3 Medicinal benefits of hibiscus sabdariffa
2.6 Flavonoid contents of fruits and vegetables fruits
2.7 Preparation of ‘zobo’ made from Hibiscus sabdariffa
2.8 Characteristics of roselle.
2.9 Uses of roselle (hibiscus sabdariffa).
CHAPTER THREE: Materials and Methods
3.0 Materials
3.1 Extraction procedure/plant materials
3.1.1 Plant materials
3.1.2 Extract preparation
3.2 Atomic absorption spectrophotometric determination
3.3 Phytochemical Analysis
3.3.1 Preparation of reagents for phytochemical analysis
3.4 Acute toxicity study
Chapter Four: Results
4.0 Phytochemical analysis
4.1 Calcium
4.2 Magnesium
4.3 Sodium
4.4 Potassium
4.5 Manganese
4.6 Iron
4.7 Copper
4.8 Zinc
CHAPTER FIVE: Discussion and Conclusion
5.1 Discussion
5.1 Conclussion
References
Appendix 1: Gallery of Hibiscus sabdariffa
CHAPTER ONE
1.0 INTRODUCTION
Toward the end of the 20th century, epidemiological
studies and associated meta-analyses suggested strongly that long-term
consumption of diets rich in plant foods offered some protection against
chronic diseases, especially cancer (Wallstromet al., 2000).Because
uncontrolled production of free radicals was thought to be significantly
implicated in the etiology of cancer (Guyton and Kensler 1993),these
observations focused attention on the possible role of radical
scavenging and radical suppressing nutrients and non-nutrients in
explaining the apparent benefit of such diets (Weisburger, 1991).
The realization that free radicals were similarly implicated in the
etiology of many other chronic diseases (Kehrer, 1993 and Stohs, 1995),
immediately focused attention on flavonoids and the foods and beverages
rich therein. An unfortunate, but unintended side effect of some
research works and papers was the misleading tendency of many
investigators to think of dietary phenols, polyphenols, and tannins
(PPT)as encompassing only the flavonoids, flavonols, and flavones. More
recent epidemiological studies have supported the association between
better health and long-term consumption of diets rich in foods of plant
origin(Hung et al., 2004 and Jansen et al., 2004).However, whether this
is because such diets minimize exposure to deleterious substances
(example oxidized cholesterol, pyrolysis mutagens, salt, saturated fat,
etc.), or maximize intake of certain beneficial nutrients (example
isothiocyanates and other sulfur-containing plant constituents,
mono-unsaturated fatty
acids, and poly-unsaturated fatty acids, PPT, polyacetylenes,
selenium, terpenes, etc.) or some combination as advocated in the
‘‘Polymeal’’ concept, remains unknown (Franco et al., 2004 and Johnson,
2004).An in vitro study indicates that there may be mechanistic basis
for true synergy between PPT and isothiocyanates. In contrast, more
recent studies seeking to assess the suggested link between the
consumption of flavonols and flavones, or other flavonoids, have given
much less consistent results. Some studies have suggested a possible
protective effect of flavonoids against vascular diseases (Hirvonen et
al., 2001 and Mennen et al., 2004) or certain (but not all)
cancers(Knekt et al., 1997 and Sun et al., 2002).Interestingly, an
investigation of the relationship between the consumption of Hibiscus
sabdariffa (zobo) and other cruciferous vegetables and the risk of
breast cancer in premenopausal women has to be carried out in order to
ascertain the beneficial effects to isothiocyanates and/or the phenolic
components of the plants (like the dietary phenols including flavonoids)
in the management of cancer growth and initiation of various types of
diabetes.
In the same time period, various studies have suggested beneficial
effect associated with raised consumption of other classes of dietary
phenols. For example, increased coffee consumption has been linked with
reduced incidence of type II diabetes (van Dam et al., 2002 and Saremi
et al., 2003).Similarly, increased consumption of lignans (or at least
greater plasma concentrations of their metabolites)has been linked with
reduced incidence of estrogen-related cancers in some (Boccardo et al.,
2004 and McCann et al., 2004) but not all studies (Kilkkinen et al.,
2004 and Zeleniuch –Jacquotte et al., 2004),and a prospective study was
equivocal.
1.1 SUGGESTIONS FOR FURTHER RESEARCH
The flavonoids in the water extract of Hibiscus sabdariffa should be
extracted for further experimental and clinical research in the
management of certain ailments and disorders like cancer, diabetes
mellitus etc.
The mechanisms of flavonoid-protein interactions have been
determined; it is my suggestion that such mechanisms should be carried
to the in-vivo metabolic and physiological processes aimed at
determining the detailed mechanisms involved in cells aging processes
and the progression of diseases.
1.2 OBJECTIVE OF STUDY
The objective of this study is to determine the physico chemical
(biochemical) and water constituent of Zobo produced from dried calyces
of Hibiscus sabdariffa (Linn Roselle). Using atomic absorption
spectrophotometer (AAS). The biochemical content of the zobo has
undesirable effects on human health when consumed.