Phytochemical content, antioxidant properties and antibacterial activities of date (Phoenix dactylifera L.) seed extracts

Abstract

This study evaluated the antioxidant and antibacterial properties of date (Phoenix dactylifera L.) seed extracts against some bacterial pathogens of food-borne diseases. The phytochemical constituents and antioxidant properties of the date seed were determined using a standard chemical method. In vitro antibacterial activities of the crude extracts of date seeds against the pathogens were determined using the agar well diffusion method. The phytochemical screenings of the extracts revealed the presence of oxalate, phytate, flavonoid, saponin, tannin and cardiac glycoside. The screening of the date seed extracts for antioxidant compounds revealed varied concentrations of total antioxidant capacity, ferric reducing antioxidant property and flavonoid. Methanol and aqueous date seed extracts exhibited appreciable antibacterial activity against E. coli, K. pneumoniae, S. typhimurium, B. subtilis and S. flexneri whereas, n-hexane extract had a mild effect on all test organisms. At 200 and 100 mg/mL of the crude extracts, all the test isolates were inhibited. Varied Minimum inhibitory and Minimum Bactericidal Concentrations of different date seed extracts showed potential bacteriostatic and bactericidal action against the test pathogens. It can be deduced that the important bioactive compounds in date seeds may be responsible for the observed antibacterial activity against the causative agents of food-borne illnesses.