Evaluation of total phenol content and antioxidant capacity of Indian jujube

The fruit of Indian jujube (Ziziphus mauritiana Lam.) has a long history of therapeutic use and prevention of disease, including anticancer, anti-inflammation and anti-obesity, and antioxidant properties. Indian jujube fruit is rich in polyphenols, cyclopeptide alkaloids, dammarane saponins, vitamins, minerals, amino acids, and polyunsaturated fatty acids. In this experiment, fruits from 14 genotypes of Indian jujube were evaluated for total phenol content (TPC) and antioxidant capacity by scavenging ABTS+ free radicals. Since the sugar contents of fruits were high, after extraction with methanol (MeOH), fractionation was carried out by ethyl acetate (sugar-free fraction) and water (sugar fraction). In the sugar-free fraction higher TPC was observed than the aqueous fraction, also the sugar-free fraction showed greater antiradical efficiency. TPC ranged from about 40 to 80 mg gallic acid equivalent (GAE) g-1 for sugar-free fraction and about 15 to 50 mg GAE g-1 for the aqueous fraction. Antioxidant capacity according to ABTS+ radical scavenging activity of sugar-free fraction was between 12.84 and 48.6 μg mL-1 Trolox equivalent antioxidant capacity (TEAC), and for aqueous fraction ranged from 19.68 to 1065.67 μg mL-1 TEAC.