Summary: | This thesis is divided into two parts the first part deals with the determination of various
essential and toxic metals in tropical fruits and vegetables available in main markets and
most frequently consumed by the major population of the city of Kota Kinabalu, Sabah.
The second part deals with the determination of metals in two marine samples namely
sea cucumber and tiger prawn. Besides these sea sediment and seawater collected from
South China Sea in Kudat area were also analyzed. Tiger-prawn (shrimp) were obtained
from locally cultured and bred in commercial ponds in Tuaran and Likas localities near
Kota Kinabalu. The determination of metals in fruits, vegetables and marine samples was
carried out using flame atomic absorption spectroscopy (FAAS).
In general, the concentrations of the bulk metals such as sodium, potassium, magnesium
and calcium were found to be present approximately in the same ratio both in vegetables
and fruits. There concentrations are found to vary in the following order: potassium >
magnesium > calcium > sodium. But the exact concentrations of potassium and
magnesium are more in fruits than vegetables whereas calcium is more in vegetables than
in fruits. The concentration of sodium is considerably low as compared with other bulk
metals. On the basis of the average RDA, it may be concluded that fruits and vegetables
can provide the required amounts of potassium and magnesium but calcium and sodium
are required to be taken from other sources including mineral supplements. The levels of
the majority micronutrient metals are found to be almost equally distributed among. fruits
and vegetables grown in Sabah as are the toxic metals: lead and cadmium.
Tiger-prawn (shrimp) were obtained from locally cultured and bred in commercial ponds
in Tuaran and Likas localities near Kota Kinabalu were found to be contaminated with
metals particularly cadmium, cobalt, chromium, iron, manganese, molybdenum, nickel,
lead and zinc. The major causes of this was found to be environmental and anthropogenic
activities in the area.
The result from the analysis of sea cucumber, sea sediments and seawater revealed that
concentration of metals particularly cadmium, cobalt, chromium, manganese,
molybdenum, nickel, lead, and zinc exceeded those in the sea sediment and sea
cucumber. The data suggest some kind of a physiological control in sea cucumber for
metal profile in the body. This animal either uses a barrier against excessive uptake or
eliminates the quantity in excess of body's capacity.
Protein denaturation in beche-de-mer stored at low temperature was also studied because
Sabah Malaysia is particularly famous for indigenous resources of this particular animal,
mainy because of its nutritional and medicinal value. Since good breeding and culturing
practice are not utilized resulting in the deterioration of the finished product. Of all the
various temperature tested, chilling at -10°C was found to be the most effective means of
controlling protein denaturation
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