الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 16 |  |  |
| | | from | 16 | | |
Abstract
Pomegranate fruit is an important source of bioactive compounds and has a protective effect against oxidative stress. Therefore, the present investigation aimed to study; the antioxidant activity of pomegranate husk extract and its hepatoprotective effect. Studies were focused on the following:
Extraction of fruit parts of three types of pomegranate at different maturity stages.
Antioxidant activity of pomegranate extracts.
The total contents of polyphenols and flavonoids and HPLC isolation of husk extract.
The effect of pomegranate husk extract as a prophylactic and medication on liver function of CCl4-treated rats.
Determination of oxidative stress biomarkers (lipid peroxidation, protein damage and DNA damage).
Histopathology examination of liver tissues.
The obtained results could be summarized in the main following points:
1. The antioxidant activity differs according to types, fruit parts and maturity stages. Among the studied types, early wonderful husk extract at pre-mature stage have the highest antioxidant activity by FRAP assay (1.32 µM).
2. The data show that the total phenolic contents in mature stage are higher than post-mature. The highest total phenol contents were observed in husk, peel and juice of EW type (12.9, 12.1 and 8.5 mg/100g dry weight).
3. Determination the flavonoid contents, Pomegranate husk and peel of premature (EW type) contained TFC (132 mg/100g) higher than juice extracts (89 mg/100g). But at other maturity stages husk extract contained TFC higher than the peel and juice extracts.
4. Using FRAP assay declared that, the early wonderful husk ethanol extract have highest antioxidant activity (total Phenolic and flavonoid contents). Phenolic and flavonoid composition were quantified by HPLC in the mentioned extract. Obtained data showed that the main phenolic compounds were Syringic acid (26.9195 %) < Pyrogallol (7.626%) < Ellagic acid (0.24439 %) < Catechein (0.22859 %) < Chlorogenic acid (0.22636 %). Main flavonoids compounds were Hisperdin (1.10516 %) < Rutin (0.015739 %) < Quercitrin (0.013292%).
5. Hepatoprotection of Pomegranate husk extract was investigated in rats intoxicated by CCl4. Data reveal that marked effect of pomegranate extract on intoxicated rat’s liver was observed ALT and AST values decreased in prophylactic group (36.5 ± 9.2 U/L and 70.6 ± 2.02, respectively) compared with CCl4 treated group (57 ± 14 U/L and 72.9 ± 1.88 U/L).
6. The bilirubin concentration in prophylactic group refers to the protective action of pomegranate husk extract (0.45 ± 0.02 mg/dL). The bilirubin level in the medication group slightly decreased (0.51± 0.02 mg/dL) when compared to CCl4 treated group (0.58± 0.02 mg/dL).
7. The albumin level and total protein level were significantly decreased in the group which treated with CCl4 compared with control. These decreases were 17.7% for albumin and 16.34% for total protein. Albumin level was increased by 5.9% and 3.5% when pomegranate extract was used as a prophylactic or medication respectively compared with carbon tetrachloride treated group. In addition, total protein level was increased by 12.56% and 16.54% when pomegranate extract was used as a prophylactic or medication respectively compared with carbon tetrachloride treated group.
8. Rats treated with carbon tetrachloride show a significant decrease (2.00±0.24a U/mg protein) in the activity of SOD enzyme compared with control group (4.59±0.29c U/mg protein). SOD enzyme activity was increased significantly with values 5.75±0.26b and 3.10±0.24ab U/mg protein when rats treated with pomegranate husk extract (2g/ kg bw) this means that damage by CCl4 could be avoided – to some extent- by husk pomegranate extract.
9. Data of glutathione content shows that the groups which treated with pomegranate husk extracts at three concentrations (P1, P2 and P3) had a significant effect on GSH content compared with control group. The pomegranate husk extract at high concentration (2g/kg bw) had a highest content of GSH (16.95±1.45a µM) compared with other concentrations (P1 = 13.98±1.45ab µM and P2 = 15.73±1.45ab µM) and control group (10.04±1.45bc) .significant lower level in group which treated with CCl4. The action of pomegranate extract in prophylactic and medication groups increased GSH level compared with carbon tetrachloride group.
10. In lipid peroxidation, Liver MDA level had a significant increase in CCl4 treated rats with value 9.18±0.49a nM/mg protein compared with control group (5.31±0.58bc nM/mg protein). Compared with CCl4-treated group, the elevation of MDA level was decreased when pomegranate extract was used as prophylactic or medication. The MDA level in prophylactic group (7.51±0.52ab nmol/mg protein) decreased more than in medication group (8.48±0.49a nmol/mg protein). Group which treated with high concentration of pomegranate husk extract (2 g/ kg bw) had a lowest level of MDA (3.6±0.58c nmol/ mg protein) compared with other groups.
11. Protein damage Study is further supported by performing SDS-PAGE of liver protein extracts. Results of Protein Pattern with molecular weight ranged from 22.7 to 146.29 kD. Polymorphism percentage was 48.14%. Lane of group treated with pomegranate extract as a prophylactic from CCl4 had four unique bands. A bands with molecular weight 102.7 and 99.5 kD absent when rats were treated with pomegranate extract in low, medium and high concentration. CCl4-treatred group and medication treated groups caused an absent in band of 124.47 kD. Protein with 114.5 kD was absent in liver protein isolated from rats which treated with CCl4 only.
12. DNA damage determine by RAPD method, the data reveal that the molecular genetic variability among the treated rat’s genomes and their controls were evaluated using 3 random primers (C1, H5 and P13). Primers gave positive and detectable bands and high level of polymorphism was generated using these primers. The molecular size of ladder bands ranged from 100 to 3000 bp.
13. Liver histology of rat treated with pomegranate extract (0.5 g/kg b.w.), (1.0g/kg b.w.) and (2.0g/kg b. w.) shows no histopathological changes. On the other hand, in case of CCl4 treated group the liver shows steatosis of hepatocytes (ballooning of hepatocytes), apoptosis and inflammatory cells infiltration. The prophylactic and medication groups have steatosis, apoptosis but lower than CCl4 group.
According to the obtained results, it could be concluded: Because the pomegranate husk ethanol extract have high contents of phenolic and flavonoid, the antioxidant activity is high. And it protect from oxidative liver damage.