Determination of nutritional and functional principles of the jujube pulp fruit, ecotype Zfisef from northeastern of Algeria

Abstract

The aim of the present work was to valorize the exotic fruit of jujube, Zfisef ecotype, growing in the western region of Algeria and highly appreciated by the population. The various analyzes of primary metabolites showed an interesting nutritional profile. The fruit pulp of jujube had a dry matter content of 81±0.21%. The amount of ash (6.1±0.16%) was high and demonstrated a wealth of minerals. Total sugars represented more than 23.20±1.85% while proteins and lipids represented only 2.88±0.32 SAB equivalent and 0.28±0.03% respectively. Vitamin C from the pulp of the fruit of the jujube tree was 194±4.36 mg/100 g of substrate and appeared significant compared to other varieties of other biotope and to fruit ripening stages. The fruit pulp of jujube (50g) gave an ethanol extract of 3.78±0.31%. The latter allowed us to determine secondary metabolites, in this case the total polyphenols (7.80±0.40 mg EAG/g) flavonoids (25.58±1.96 mg EQ/g) gallic tannins (0.15±0.025 μg EAG/100g) catechin tannins (3.48±0.28 μg ECT/mg) total anthocyanins (4.81±0.44 mg ECy3g/100g) and total carotenoids (5.02±0.19 mg E b-carotene/100g). These biologically active molecules conferred to the product good DPPH antioxidant activity (56.60±3.99% with PFJ extract concentration of 0.25±0.062 mg/ml). Concentration of product required for 50% inhibition was 0.22mg/ml. Iron reduction power of our jujube fruit extract exhibited a good antioxidant activity compared to ascorbic acid. Also the presence of many phenolic compounds determined by LC-MS/MS with var-ied identities and antioxidant characters generate interest in making this product a functional food.