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
Vibrio parahaemolyticus causes acute gastroenteritis associated with the consumption of contaminated raw or under cooked seafood. The virulence of vibrio parahaemolyticus is initially attributed to the production of a thermostable direct hemolysin [TDH]. The survey of different concentrations of garlic essential oil [Allium sativum] on MIC, MBC, growth curve and production of TDH toxin of vibrio parahaemolyticus. The effects of garlic essential oil at concentrations of 0, 0.005, 0.015, 0.03 and 0.045% on the MIC, MBC, growth curve and production of TDH toxin of vibrio parahaemolyticus were studied in BHI model. MIC and MBC of garlic essential oil was estimated 0.03%. The essential oil showed significant effect on toxin production, Titers of TDH production in 0 and 0.005% were 1/256 comparing to 1.64 in 0.015% concentration of EO. Concentrations of 0.005 and 0.015% of garlic essential oil reduced the bacterial growth rate significantly [p<0.05] compared to the control group. Garlic essential oil showed to be effective against bacterial growth and production of TDH toxin. Its potential application in food systems may be suggested
ABSTRACT
Consumption of contaminated seafood with Vibrio parahaemolyticus results in gastroenteritis in consumer. Thermostabledirecthaemolysin is one of the major virulence factors of this emerging pathogen which has an important role in its pathogenicity. The objective of this study was to evaluate the effect of Zataria multiflora Boiss. essential oil and acetic acid on the production of TDH toxin of Vibrio parahaemolyticus in subinhibitory concentrations of these preservatives. The toxin production under specific condition including the combination of different concentrations of the essential oil [0, 0.005, 0.015, 0.03 and 0.045%], pH values [5.5, 6.5 and 7.5] modified with acetic acid and 3 incubation temperatures[8, 25 and 35[degree sign]C]in BHI broth medium was studied and the number of the bacteria have been counted and the toxin production has been evaluated after the growth of the organism and subsequent turbidity in the medium using the KAP-Rpla commercial kit. Toxin titerproduced in a broth with pH value of 7.5 and 35[degree sign]C and in the absence of essential oil was 1/256 while it was 1/32 in the same condition and with the presence of 0.015% essential oil. Also the titer of this toxin in 25[degree sign]C and pH of 6.5 equals 1/256 while with adding the 0.015% ofZataria multiflora Boiss. essential oil, It reduced to 1/3. According to the results the essential oil in combination with different pH values and incubation temperatures has a decreasing effect on the toxin production of Vibrio parahaemolyticus. It suggests that further studies with the same conditions as current study in a food model is needed to confirm the positive effect of these natural preservatives
Subject(s)
Bacterial Proteins , Hemolysin Proteins , Acetic Acid , Oils, VolatileABSTRACT
Zataria multiflora Boiss. is one of the Iranian traditional spices and it has antimicrobial effect on the pathogenic bacteria which are agents for some current foodborne intoxications. The present study was conducted to evaluate the antimicrobial activity of Zataria multiflora Boiss. Essential oil on Escherichia coil 0157:H7. Minimum inhibitory concentration [MIC] and minimum bactericidal concentration [MBC] of Zataria multiflora Boiss. Essential oil [EO] for Escherichia coil 0157:H7 at 35°C, the effect of subinhibitory concentrations of EO on growth curve of bacteria up to 24 hours at 25 and 35°C and also production of shigatoxin 2 [Stx2], at 35°C has been determined. MIC and MBC of EO which have been evaluated were 0.04 and 0.06%, respectively the effect of subinhibitory concentrations of EO on bacterial growth curve during 24 hours has been determined by spectrophotometer device at 25 and 35°C and also production of shigatoxin 2 [Stx2], at 35°C has been determined. Subihibitory concentrations of EO, significantly, decreased the production of Stx2 at 35°C in a dose dependent manner. The results showed that Zataria multiflora Boiss. Essential oil had inhibitory effect on Escherichia coli 0157:H7 and it can be used as a natural preservative in food industry
Subject(s)
Escherichia coli O157 , Spices , Oils, Volatile , Shiga Toxin 2 , Plants, MedicinalABSTRACT
In order to reduce or eliminate foodborne pathogens or food spoilage agents many research have been done to find natural preservatives. This study was carried out to determine minimum inhibitory concentration [MIC] of lysozyme and Zataria multiflora boiss. essential oil on E. coli 0157: H7 and their sub inhibitory concentration effect on bacterial growth curve. In this study different concentrations of lysozyme [0. 125, 250, 500 and 1000 micro g/ml] and Zataria multiflora boiss. essential oil [0, 0.005, 0.01, 0.02, 0.04 and 0.08%] were used alone and in combination on BHI broth to determine MIC of Zataria multiflora boiss. essential oil and lysozyme with macro dilution and micro dilution methods and effect of sub inhibitory concentrations of them on bacterial growth curve of E. coli 0157: H7. MIC of essential oil in two methods was achieved 0.04% whereas lysozyme in 100 micro g/ml concentration was not able to reduce bacterial growth. Furthermore combination results revealed that high concentration of lysozyme was not able to reduce calculated amount of MIC of essential oil. Sub inhibitory concentration effect of EO and lysozyme showed that their combination result in the increase of lag phase and reduction of bacterial growth. Utilization of EO and lysozyme together did not decrease MIC but combination of them increase lag phase
Subject(s)
Microbial Sensitivity Tests , Foodborne Diseases/prevention & control , Food Preservatives , Escherichia coli , MuramidaseABSTRACT
Application of natural compounds, including essential oils [EOs] and lysozyme is an effective method against growth of bacterial pathogens in foods. Determination of minimum inhibitory concentration [MIC] of lysozyme and Zataria multiflora Boiss. essential oil on L. monocytogenes. In this study different concentrations of lysozyme and Zataria multiflora Boiss. EO were used alone and in combination on BHI broth to determine MIC of Zataria multiflora Boiss. EO and lysozyme with macro dilution and micro dilution methods and effect of sub inhibitory concentrations of them on bacterial growth curve of L. monocytogenes. The minimum inhibitory concentration [MIC] of Z. multiflora Boiss EO was estimated ?0.04 using macro and microdilution. lysozyme at the highest concentration [1000 microg/ ml] was not effective in inhibition of bacterial growth and no MIC value obtained. Combination of EO and Lysozyme decreased the MIC value to%0.02 and 250microg/ mlfor Z. multifloraBoiss. EO and lysozyme, respectively. The results of growth curve analysis showed that combination was effective in increasing the lag phase. Z. multiflora Boiss and lysozyme showed to be effective against bacterial growth and its potential application in food systems may be suggested
ABSTRACT
Essential oils and their components have antimicrobial effects. They use with spices as flavoring agents all over the world. They have been used safely since ancient times as herbal medicines. Zataria multiflora Boiss. is one of medicinal herbs in Iran and its antimicrobial effects on foodborne pathogens have to investigate in foodstuff. The aim of this study was to determine of the effect of Zataria multiflora Boiss. Essential oil on the growth of Listeria monocytogenes in salted [4%] silver carp. Effect of different concentrations of this Essential oil [0.0%, 0.045%, 0.135%, 0.405%, and 0.810%] on behavior of Listeria monocytogenes was determined by evaluation of the bacterial growth in salted fish fillets. The essential oil in used concentrations had significant inhibitory effect on the growth of Listeria monocytogenes in salted fish during the storage time. The higher concentration until 0.405%, the more significant inhibitory effects on the growth of Listeria monocytogenes [p<0.05] but 0.405% and 0.810% concentrations had no different significant inhibitory effects on the growth of Listeria monocytogenes [p>0.05]. Organoleptical survey showed that the concentrations of the essential oil used until 0.405% not only had no undesirable effect on flavoring but also it improve taste and flavor of salted fish. The result suggested that the Zataria multiflora Boiss. Essential oil can be considered as a natural preservative in salted fish
Subject(s)
Animals , Oils, Volatile , Listeria monocytogenes , Fishes , PhytotherapyABSTRACT
Thyme [Zataria multiflora Boiss.] is one of the Iranian traditional spices and it has antimicrobial effect on the pathogenic bacteria which are agents for some current food borne intoxications. The aim of this study was to evaluate the antimicrobial activity of Zataria multiflora Boiss. essential oil on V. parahaemolyticus in salted [8% Nacl in tissue] silver carp. Effect of different concentrations of this Essential oil [0.0%, 0.045%, 0.135%, 0.405%, 0.810%] on behavior of V. parahaemolyticus in two temperatures [15, 25 C] was determined by evaluation of the bacterial growth in salted fish fillets. The essential oil in used concentrations had significant inhibitory effect on the growth of V. parahaemolyticus in salted fish compare with control treatment during the storage time [p<0.05]. There was no significant difference between all treatments. The results showed that Zataria multiflora Boiss. Essential oil had inhibitory effect on V. parahaemolyticus, therefore it can be considered as a natural preservative in salted fish