Determination of Antioxidant Capacity, Total Phenolic and Flavonoid Contents of Zahdi Date Seed and Their Effect on Beef Patties

Abstract

The study included preparation of aqueous (As) and alcoholic (ethanolic Es,methanolic Ms) and oil extracts (Os) of Zahdi date seeds (Zs)(Phoenix dactylifera) . Chemical content of date seed was studied and the total content of phenols and flavonoids were estimated for prepared extract. Bioactive compounds of this extract was identification by Gas Chromatography Mass Spectrometer GCl MS. Antioxidant activity , reducing power, chelating of iron ions of extract was studied , then used the extract which gave highest antioxidant activity in beef patties with two concentrations 0.05% and 0.1% to test their efficiency in oxidative inhibition and prolonging the reservoir age of stored beef patties in refrigerated for 10 – days and following chemical indicators in Peroxide value(PV) , Thiobarbituric acid(TBA) in treated beef patties . Moisture , protein ,oil, ash and carbohydrate contents of Zs 9.36%, 4.87% , 8.56% , 1.34%, 75.87% respectively . All extracts containing many bioactive compounds that identification of GC-MS and differented in their percentage according to the type of extract. All extracts share with some bioactive compound as 1-(+)-Ascorbic acid 2,6-dihexadecanoate, gamma.sitosterol ,Octadecanoic 5-Methyl-2-ethylamino-2-thiazoline, acid , Hexadecanoic acid and 2-hydroxy-1-(hydrixymethyl)ethylester . Alcoholic extracts (Es and Ms) exhibited the highest content of phenolic compound compared with As was 67.32mglml for Es , Ms was 65.32mglml While the total content of flavonoids for As 33.32mglml and Es 52.16 mglml , 46.16mglml for Ms , As and alcoholic extracts of Zs exhibited antioxidant activity was 88.70% for Es and 87.02% for Os , 85.22% for Ms , but As was the lowest 43.01% . The prepared extracts showed the higher reducing power was 2.63 and Chelating of iron ions 60.93 % and for Es ,There was a significant decrease (P<0.05)in peroxide value and thiobarbituric acid in beef patties treated with ethanolic extracts compared with control.

Keywords

• total phenolic content,,
• ,،,؛zahdi date seed,,
• ,،,؛antioxidant activity,,
• ,،,؛lipid oxidation