evaluating the feasibility of producing antimicrobial film based on sodium caseinate and essential oil of zataria multiflora boiss

in this study, antimicrobial effects of zataria multiflora boiss added to sodium caseinate film on four bacterial species: staphylococcus aurous, escherichia coli, bacillus subtilis and salmonella intertidis was investigated. disk diffusion method was used to study the antimicrobial activity of zataria multiflora boiss in sodium caseinate film. 9 mm disks were prepared from produced films with different concentrations of zataria multiflora boiss. with 1, 2, 3 and 4%. surface culture was done under sterile condition using 0.1 ml of broth culture of each bacterial (106 -107 cfu/ml) on bhi agar. then the disks were placed. diameter of inhibition zone was considered as an index of antimicrobial activity of the film. statistical analyses were done by means of sigmasdat software and mean comparison was carried out by lsd test. results showed that disks containing essential oils of zataria multiflora boiss. in each concentration inhibited growth of e.coli, sa.interitidis and b.cereus. since there was no significant differences between 3% and 4% concentrations for these bacteria (p>0/05), concentration of 3% is the most appropriate and cost-effective concentration with the highest antimicrobial effect. only the film containing 1% of essential oil of zataria multiflora boiss. made no inhibition zone on s.aurous, in the other word had no inhibitory effect in this concentration. but inhibition zones created by 2, 3 and 4% for s.aurous were significantly different (p<0/05). results showed that essential oils of this plant can be used as a natural preserving in composition of edible film for packaging of food products