الفهرس 
1. INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Heavy metals are released into the environment by activities of
people and high levels of these metals constitute a great risk for the
aquatic ecosystem and human. so that Lead and cadmium are a
widespread environmental pollutant, which has been implicated in toxic
processes. It is still mined and added to many products including paints,
eye cosmetics, gasoline, water pipes , air pollution, tobacco, and food.
and health care supplies . Lead poisoning affect several organ systems in
man and other mammals and is associated with a number of
morphological, biochemical and physiological changes, including
impairment of liver function, nervous system disturbances, abnormal
glucose metabolism, kidney dysfunction and hematological disorders.
Cadmium, a toxic heavy metal was first reported as an occupational
health hazard. Exposure to cadmium causes various adverse effects in
humans such as kidney dysfunction, liver injury, osteoporosis, and
cancer. So that can be reduced harmful effect of heavy metals by using
chitosan from shrimp shells there for its ability to adsorption of these
metals, thereby reducing the harmful impact from them.
Therefor, this study was carried out to evaluate Reducing the
harmful effects of heavy metals in rats by chitosan extracted from shrimp
shells.
Sixty-six adult Male albino rats, weighing (170±5) g of Sprague
Dawley strain were fed the standard diet for one week then divided into
three groups according to the following:
The first, negative control group (n = 6), fed standard diet.
The second group (lead intoxication rats), (n = 30) Lead groups were
fed standard diet and given orally a daily dose of 25mg/kg body weight
for 30 days lead acetate then divided into 5 subgroups, 6 rats per
subgroup according the following:
Subgroup 1. Positive control fed standard diet.
Subgroup 2. Received a daily oral dose of commercial chitosan (50
mg/kg) B.W for 30 days.
Subgroup 3. Received a daily oral dose of commercial chitosan (100
mg/kg) B.W for 30 days.
Subgroup 4. Received a daily oral dose of shrimp shells chitosan (50
mg/kg of B.W) for 30 days.
Subgroup 5. Received a daily oral dose of shrimp shells chitosan (100
mg/kg of B.W) for 30 days.
The third group (cadmium intoxication groups), (n =30) Cadmium
groups were fed standard diet and given orally a daily dose of 2mg/kg
body weight for 30 days cadmium then divided into 5 subgroups, 6 rats
per subgroup according the following:
Subgroup 1. Positive control fed standard diet.
Subgroup 2. Received a daily oral dose of commercial chitosan (50
mg/kg) B.W for 30 days.
Subgroup 3. Received a daily oral dose of commercial chitosan (100
mg/kg) B.W for 30 days.
Subgroup 4. Received a daily oral dose of shrimp shells chitosan (50
mg/kg of B.W) for 30 days.
Subgroup 5. Received a daily oral dose of shrimp shells chitosan (100
mg/kg of B.W) for 30 days.
At the end of experimental period (30 days), animal weiged and the
relative of oranges weights (liver, brain, heart, kidney, spleen and lungs)
were calculated . Also, blood samples were collected to determine
glucose level, lipid profiles, liver and kidney function. Moreover,
histopathological changes on liver and brain were determined.
The obtained results can be summarized as follows:
First: Chemical composition and total phenols of crude shrimp shells
and chitosan.
1. The shrimp shells chitosan had lower content of moisture (8.33%), fat
(0.54%), protein (1.5%), ash (0.27%) and total phenols (184.7mg/
l00g) and higher (p≤ 0.05) carbohydrate (55.8%) and fiber (33.4%)
than crude shrimp shells .
Second : Blood analysis:
1. Improvement of lead and cadmium levels in serum, liver and brain
were observed in rats feed chitosan than other groups.
2. Feeding rats with 50 mg/kg body weight (BW) of commercial chitosan
(CC1) and 100 mg/kg BW of shrimp shells chitosan did not
significantly differ in their reducing effect on lead and cadmium in
serum, liver and brain.
3. The highest reduction of lead and cadmium level in serum, liver and
brain was observed in rats feeding 100 mg/Kg BW of commercial
chitosan (CC2).
4. Blood glucose level decreased in rats feed commercial and shrimp
shells chitosan.
5. The highest reduction of glucose level was observed in rats fed 100
mg/Kg BW of CC2 in lead 17.36% and cadmium groups 14.6%
respectively.
6. Administration rats with chitosan led to reducing ALP, AST and ALT
than positive group.
7. Administration rats with CC2 was more effective in reducing ALP
(14.54%), AST (21.56%) and ALT (29.18%) as compared with
positive group .
8. Administration rats with chitosan led to reducing urea, creatinine and
uric acid level in lead and cadmium groups than postive groups.
9. Administration CC2 to lead and cadmium groups rats reduced urea,
creatinine and uric acid levels as compared rats feed CC1 and SC (50
and 100 mg/kg BW).
10. Feeding lead and cadmium groups with (CC1) and SC2 did not
significantly differ (p>0.05) in their effect reduction on urea,
creatinine and uric acid level .
11. Total lipids in positive control were increased after oral
administration with lead acetate and cadmium compared with negative
control while HDL had an opposite trend.
12. Administration rats commercial chitosan CC2 to rats reduced total
lipids levels as compared with rats feed CC1 and SC (50 and 100
mg/kg BW).
13. The HDL level was increased by 49.5% ,133.6 , 28.5 and 56.5% in
rats fed CC1 ,CC2 , SC1 and SC2 respectively .
14. Catalase and GTF were increased by feeding rats with CC1 , CC2 ,
SC1 and SC2 in lead and cadmium groups.
15. Supplementation rats t with CC2 was more effective in increasing
GTF and catalase than other groups.
Third : Biological changes:
1. Administration rats with chitosan reduced the weight loss resulting
from cadmium and lead effect.
2. Relative weights gain was more effective in lead groups
supplementation with chitosan as CC1, CC2, SC1 and SC2 by 17.0%,
9.6%, 21.6% and 14.6% respectively than positive control group by
24.2%.
3. Administration rats with CC2 to rats was more effective for
improving relative weights gain and relative organs weight from lead
and cadmium poisoning than CC1, SC1 and SC2.
4. Administration rats with CC2and SC2 resulted in pronounced
protection against lead and cadmium induced alterations and the
hepatocyte appeared nearly within a normal pattern. Moreover group
supplementation with showed the best treatment in histological
examination for liver tissues and brain.
5. Breads prepared with 7% of shrimp shells chitosan had higher rating
score than control and breads prepared with 3.5% of shrimp shells
chitosan
These results suggest that supplementation with chitosan reduced
harmful effect of lead and cadmium.