Evaluation of antimicrobial potential of nigella sativa oil in a model food matrix

Abstract

Nigella sativa (black cumin) is known for its antibacterial activity. However, available literature does not sufficiently explore the possible interactions with the natural wild microflora in complex food matrices. This study is using as model food matrix, a traditionally manufactured cheese, without additives, without starter cultures and without pathogen culture, to study the antimicrobial effect of Nigella sativa seed oil (NSSO), as well as the physicochemical properties of this food matrix during the study. The experiment included three batches of food matrix: control batch without NSSO, 0.1% and 0.2% w/w NSSO enriched batch. Natural occurring E.coli, coliforms and Staphylococcus spp. were significantly inhibited by NSSO. Total bacterial count (APC) registered significant improvement during the experiment. The antimicrobial activity of NSSO proved selective, as no significant effect was seen on the beneficial LAB. NSSO significantly improved the sensory qualities of the food matrix samples. NSSO kept significant selective antimicrobial effect when used with a complex food matrix, without altering the physicochemical properties of this food matrix, suggesting that NSSO could be a natural antibiotic candidate that could be used as food dietary supplement.