Study On Hypoglycemic Constitents Of Pomegranate Seed

Pomegranate, as a pharmacological fruit, has a very high medicinal value becauseit is a known rich source of bioactive compounds, and which has significantly higherantioxidant substance than grape, cranberry, grapefruit and orange. The pomegranateshows good antioxidant activity for the including of the bioactive substances such asflavonoids, ellagitannin, gallic tannin, ellagic acid, catechin, anthocyanins, vitamin Cand so on. And many studies have found that pomegranate peel, pomegranate seed,pomegranate flower and leaf have a hypoglycemic effect.In order to determine the contents of total phenol and polysaccharides of thepomegranate seed, Folin-Ciocalteu and phenol hydrate-sulfuric acid method werecarried. And we evaluated the hypoglycemic effect of polyphenols and polysaccharidesof pomegranate seed through the diabetic rats induced by alloxan. Main researchresults are as follows.1．The extraction condition of pomegranate polyphenols was optimized byorthogonal experiment. The effects of ethanol concentration, extraction temperature,extraction time and ratio of material to liquid on the polyphenol extraction wereresearched in this experiment. The optimum extraction condition was as follows: ratioof pomegranate seed powder to ethanol-water (60%, volume part)1:20at60℃for1h.Under this condition, the content of pomegranate seed polyphenol was2.431mg/g drymatter. The reducing power of pomegranate seed polyphenol was15.301mgVC/g drymaterial.2. The extraction condition of pomegranate polysaccharide was optimized byorthogonal experiment. The effects of extraction temperature, extraction time and ratioof material to liquid on the polysaccharide extraction were researched in thisexperiment. The optimum extraction condition was as follows: ratio of pomegranateseed powder to distilled water1:25at40℃for90min. Under this condition, thecontent of pomegranate seed polysaccharide was20.116mg/g dry matter.3. All rats were divided into8groups in the animal experiment: Group (1,2,3):rats were fed on basal diet and polyphenol extracts(100,200and400mg/kg), Group(4,5,6): rats were fed on basal diet and polysaccharide extracts(100,200and400mg/kg), Group7: hyperglycemic rats, Group8: control group. The animal experimentdemonstrated that the fasting plasma glucose value of polyhenol groupes were decreased by3.33%,1.46%,5.34%in the16days and decreased by4.13%,3.92%,9.25%in the32days compared with the control group. And the polysaccharidesgroups were decreased by2.98%,6.36%,8.02%in the16days and decreased by5.11%,11.22%,16.33%in the32days compared with the control group. The resultsindicated that the polysaccharides and polyphenols of the pomegranate seeds providedhypoglycemic ability, and the hypoglycemic effect will be enhanced along with theincreasing of the concentration of polysaccharides and polyphenols. Moreover, thepresent study demonstrated that the hypoglycemic ability of polysaccharides was betterthan that of the polyphenols.