Affiliation:
1. College of Pharmaceutical and Food Sciences, University of Antioquia, Street 67, No. 53-108, Medellin, Colombia
2. Institute of Food Science and Technology (INTAL), Carrera 50g No. 12S-91, Itagüi, Colombia
Abstract
This study evaluated the antimicrobial activity (i.e., against Bacillus cereus and Staphylococcus aureus) and the antioxidant activity (i.e., ABTS, FRAP, and DPPH) of annatto seeds extract obtained by ultrasound-assisted extraction. A response surface design with three levels such as pH (2-11), solvent concentration (50-96 %), seed-to-solvent ratio (1:2–1:10), and treatment time (0-30 min) was employed to determine the optimal experimental conditions. Thus, a pH of 7.0, seed-to-solvent ratio of 1:7, and treatment time of 20 min were selected as optimal rendering an extract having a 0.62% of bixin, 3.81 mg gallic acid/mg equivalent of polyphenol compounds (ABTS 1035.7, FRAP 424.7, and DPPH 1161.5 μM trolox/L), and a minimal inhibitory concentration against Bacillus cereus and Staphylococcus aureus of 32 and 16 mg/L, respectively. Further, the main bioactive compounds identified by LC/ESI-MS were bixin and catechin, chlorogenic acid, chrysin, butein, hypolaetin, licochalcone A, and xanthohumol.