ABSTRACT
Various studies have been conducted to show the effects of essences and enzymes on foodborne pathogens in culture media. The aim of this study was to determine the effect of Zataria multiflora Boiss. essential oil and lysozyme alone and in combination on preventing growth of Vibrio parahaemolyticus in culture media. In this study, the MIC of Zataria multiflora Boiss. essential oil and lysozyme, together and alone, on Vibrio parahaemolyticus, was determined by using macro and microdilution methods. The MIC of Zataria multiflora essential oil determined 0.01% and 0.02% by using macro and microdilution methods, respectively and lysozyme at 1000 mg/mL concentration could not inhibit the growth of V. parahaemolyticus. According to the results of current study, Zataria multiflora essential oil showed better results in comparison with lysozyme, moreover Applying lysozyme and essential oil together did not decrease MIC, but extended the latent phase of V. parahaemolyticus, which considered an important factor in microbiology
ABSTRACT
The film containing antimicrobial agents are a type of active packaging which is mainly designed to control microbial and chemical spoilage of food. The aim of this study was to evaluate the antimicrobial, antioxidant and color properties of chitosan film incorporated with essential oil of Zataria multiflora Boiss [ZEO]. In this experimental study which was conducted at Urmia University of Medical Sciences between 2009-2010, the chemical composition of ZEO was analyzed using GC-MS. Chitosan films containing 0, 0.5, 1 and 2% ZEO, were obtained by casting method and subsequently, total phenol [TP], antioxidant, color [accordance with hunter system [L*[luminosity], * [redness, and b* [yelloweness]] and antimicrobial characteristics of films on Listeria monocytogenes were studied. The collected data was analyzed by the SPSS software. The order of TP for all films in the experiment was 2% ZEO>1% ZEO%0.5% ZEO> unsupplemented chitosan film, respectively. It was also conducted that the antioxidant activity of chitosan films was increased by adding various concentrations of ZEO. These increases were significant for film containing 1% [33.98%] and 2% [37.77%] ZEO [p<0.05]. Regarding the color luminosity [L*] of the chitosan film, results indicated no significant changes by incorporating ZEO, whereas the incorporation of ZEO into films had a significant effect on film yellowness, evidenced by lower b* values. Finally, it was shown that the presence of ZEO in chitosan films significantly modified the anti-listerial activity of chitosan, [p<0.05]. The results indicated that an active film from chitosan could be achieved by incorporating ZEO. Addition of ZEO improves functional and antibacterial characteristics of chitosan film
Subject(s)
Anti-Bacterial Agents , Antioxidants , Oils, Volatile , Listeria monocytogenesABSTRACT
In food industry, quality assurance and prolongation of shelf-life is achieved through control of pathogenic and spoilage microorganisms in foods. Regards to much proved adverse effects of synthetic food additives and general concern on the subject, the replacement of these additives with natural based ones such as plant essential oils and natural antibiotics has been raised and researches first at in virto models and then in food systems is necessary. The aim of this study was to determine the antimicrobial activity, minimum inhibitory concentration [MIC] and minimum bactericidal concentration [MBC] of Zataria multiflora Boiss. Essential oil and nisin alone and in combination against Listeria monocytogen in brain heart infusion [BHI] broth. The specifications of combination of essential oil and nisin were determined. In this study 600 micro g/ml of Z. multiflora essential oil and 2.5 micro g/ml nisin in pH value of 5 at 15 [degree sign] C were used. In this study Zataria multiflora essential oil had antimicrobial effects agains Listeria monocytogen [MBC: 19, MIC: 9.5 micro g/ml]. Combination of nisin and the essential oil had also antimicrobial effects against Listeria monocytogen [MIC: 1.2, MBC:2.4 micro g/ml]. Zataria multiflora essential oil and nisin were effective against Listeria monocytogen alone. This effect was obviously increased in combination with each other and the results were noticeable