Background:
Biogenic amines are the end products of bacterial decarboxylation of amino acids which occur as a result of bacterial contamination. Those may cause a series of problems for human health such as allergic reactions, itching, breathing difficulties, fever and hypertension.Objectives: This study aimed to isolate different bacteria that can produce decarboxylase enzymes and trail to control it by using garlic, onion and ginger nano-emulsions. Methods: Isolation and identification of some bacteria producing decarboxylase enzymes from minced meat, preparation of garlic, ginger and onion nano-emulsions (۶۰%) and investigating their cytotoxicity by sulforhodamine B (SRB) assay. Then, the antibacterial effect of the prepared nano-emulsions against the isolated bacteria was explored by determination of their minimum inhibitory concentrations (MICs) and measuring biogenic amines levels by high performance liquid chromatography (HPLC). Results: The most common bacteria isolated from samples were Salmonella species “Salmonella Typhimurium۱, ۴{۵},۱۲: i: ۱.۲ and Salmonella arizonae”, Escherichia coli “serotype O۴۴: K۷۴ and O۱۲۵: K۷۰”, Klebseilla pneumonia, Enterobacter spp, Staphylococcus aureus, Aeromonas hydrophilia, Proteus mirabilis, Pasteurella multocida and Lactobacillus species. The biogenic amines detected on positive samples were putrescine, cadaverine, spermidine, spermine, putrescine, B-phenyl ethyl amine, histamine and tyramine. The sizes of the ginger oil nanoemulsion ۶۰%, garlic oil nanoemulsion ۶۰% and onion oil nanoemulsion ۶۰% were (۲۲۲.۶±۲.۲۲ nm, ۴۲۰.۷±۳۶.۹۵ nm and ۲۰۲.۹±۲.۱ nm) respectively, indicating that they were safe and stable. The antibacterial effect of the used nano emulsions showed that Salmonella spp, E. coli and S. aureus were the most sensitive strains while K. pneumonia and Enterobacter spp. were the most resistant ones. The level of the detected biogenic amines were reduced greatly after addition the oil nanoemulsions ۷.۵% to examined samples.Conclusion: Using of plant extract as ginger, garlic and onion nanoemulsions oils as antibacterial agents and for reduction of biogenic amines was more effective.
