جستجوی مقالات مرتبط با کلیدواژه "اسانس آویشن شیرازی" در نشریات گروه "صنایع غذایی"

Shirazi thyme is a perennial herbaceous plant related to Lamiaceae family growing in central and southern regions of Iran. This study aimed to assess chemical composition, bioactive functional groups, antioxidant potential, total phenol, and total flavonoids of Shirazi thyme essential oil (STEO) and also to evaluate its cell toxicity effect against the colorectal cancer cell line (HT29).
 
The chemical composition of STEO was identified by gas chromatography-mass spectrometry. The bioactive functional groups of STEO were measured by Fourier transform infrared at spectra range of 500- 4000 cm-1. The total phenol and total flavonoids of STEO were determined by folin- ciocalteu and aluminum chloride colorimetric method, respectively. MMT method was performed to measure the cell toxicity of STEO against the colorectal cancer cell line (HT29). The cells were cultured on DMEM high glucose medium supplemented with 10% fetal bovine serum and penicillin/streptomycin and incubated at 37°C with 95% relative humidity and 5% CO2 concentration. The antioxidant activity of STEO was evaluated by DPPH and ABTS free radicals scavenging assays. Duncan test at 5% probability and SPSS software (version 18) was performed to compare the means of obtained results.
 
Based on GC/MS spectrometry, a total of 29 constituents were identified and quantified in the STEO representing more than 99% of total constituents. Thymol with 39.3% and Carvacrol with 30% were the most constituents of STEO. The other major compound of STEO were Benzene (8.52%), γ-Terpinene (5.27%), and Caryophyllene (2.97%). The presence of peak at a wavelength of 320- 1000 cm-1 demonstrates O-C bound that could be related to organic compounds such as alcohols, carboxylic acids, esters, and ethers. The peaks occurred at spectral range between 2800- 3000 cm-1 (particularly at 2869.6 up to 2960.8 cm-1) are related to the stretching mode of C-H bounds and are mostly associated with alcoholic compounds in the essence. The amount of total phenol and flavonoids of STEO were 64.05 mg gallic acid equivalent/g and 11.68 mg quercetin equivalent/g, respectively. Results obtained from antioxidant activity of STEO with DPPH and ABTS free radicals scavenging showed that by increasing of STEO, the inhibition level of free radicals was enhanced. The inhibition percent of free radicals by using DPPH and ABTS at 1000 ppm concentration were 63.69% and 64.33%, respectively. The cell toxicity results of different STEO concentrations against the cell line HT29 revealed that survival of HT29 cells at 1, 3.125, 6.25, 12.5, 25, 50, 100 and 200 ppm of STEO were 100, 70.15, 61.19, 59.33, 38.83, 25.68, 20.65 and 12.2%. According to the results of this study, as the concentration of STEO increased, its effect on the cell line HT29 enhanced and the cell percentage viability decreased. Some antioxidant activity of STEO could be interrelated to its phenolic compounds. Based on the results of antioxidant activity, the amount of total phenol and flavonoids and the effect of STEO on cell toxicity against the cell line HT29, it seems that the use of STEO is applicable in the pharmaceutical and food industries

Nowadays, the interest in using food coatings and films such as bacteriocins and plant essential oils, due to factors such as environmental concerns due to the use of synthetic packaging materials, the need for new methods and opportunities to create new markets for food products, the need for food to increase. The shelf life of products and the tendency of consumers to consume natural materials are expanding. Nanotechnology in edible coatings can increase their efficiency compared to conventional edible coatings by reducing particle size and smaller pore sizes, and improve the quality of packaging materials. The high ability of chitosan to form a film has made it possible to use it as a suitable food coating. Essential oils with antibacterial properties can be used to enhance the antibacterial properties of chitosan. Also, foodborne illness has always been one of the most important human concerns and the present study was conducted to investigate how to reduce these risks.The objective of this paper was to investigating the chemical composition of Zataria multiflora Boiss essential oil, and its application with nisin in Nano-emulsion of chitosan-based coatings containing Nano-emulsion against the Listeria monocytogenes in chicken fillets, kept at cold temperatures (4±1°C) during a 16-days period and Antibacterial activity of essential oil (as emulsion and Nano-emulsion) against the studied bacterium was evaluated by the MIC and MBC methods.

The chemical composition of the essential oil was determined using gas chromatography, and the treatments were divided into the six groups of: without coating (control), chitosan, Nano-chitosan, Nano-chitosan containing essential oil, Nano-chitosan + nisin, and Nano-chitosan + essential oil + nisin. The samples were then transferred to the refrigerator for bacterial counting on days 0, 2, 4, 8, 12, 16.

Carvacrol 44.36%, thymol 30.14% and gamma-terpinene 8.31% were identified as the most important compounds in the chemical composition of the Zataria multiflora Boiss essential oil. The mean logarithm of the number of bacteria counted in the 16-days period showed a significant difference between the groups (p <0.05). The present study showed that the highest inhibitory effect on the bacteria compared to the control group ware noticed in treated samples with chitosan Nano-emulsion containing nisin and Zataria Multiflora Boiss essential oil group.

The results of this study showed that Nano-emulsion of chitosan edible coating is the effectively capable of inhibiting the growth of pathogenic Listeria monocytogenes bacteria in chicken fillet samples at cold temperatures and its use can be considered in the food industry.

In this work, the effectiveness of temperature, oxygen and Thymus vulgaris essential oil (Zataria multiflora) coated on the respiration rate of oranges (Citrus sinensis L.) cv. Valencia was studied to properly develop modified atmosphere packaging. Respiration rate of orange in the close system was studied at the range of temperature 5, 10 and 250C as well as the essential oil in the 3 level from 125, 250 to 500 ppm. A Michaelis–Menten-type equation, with the model constants used to describing the respiration rate of fruit. Our results show the efficacy of modelling for predicting of respiration rate in the varying oxygen concentration and storage time. Arrhenius-type relationship, was used for predicting respiration rate on varying the temperature. The results indicated that increasing in the storage temperature leading to decrease in the time of respiration rate and reach equilibrium state. The maximal respiration rate ( ) and value changes in the exponential and linear manner respectively with increase in the temperature. As well as, the essential oil coating led to decrease in the model parameters value estimated. The activation energy of the respiration rate based and for oranges was calculated at 53.12 and 21.18 respectively. In addition, the value of activation energy increased to the higher value in the presence of essential oil coating.

Thymus vulgaris is one of the most well-known medicinal plants which its essential oil contains various active ingredients such as thymol and carvacrol with antioxidant, antibacterial, and antifungal activities. This essential oil is very sensitive and loses its properties against different factors. Microencapsulation process is performed for protecting volatile and sensitive compounds to chemical reactions. Modeling of this process can be effective in assessing and predicting conditions affecting on qualitative properties of the product. The purposes of this study are optimization of the production conditions of Thymus vulgaris essential oil microencapsulation and performance comparison of response surface and artificial neural network methods.

In this study, oil in water emulsions, consisting of 5% (weight/weight) of thyme essential oil in an aqueous suspension containing wall materials (10, 33.13, 20, 26.66 and 30%), with different protein (sodium caseinate) to polysaccharide (modified starch and maltodextrin) ratios (0, 66.6, 20, 33.33 and 40%), were prepared by the help of ultrasonic waves (30, 45, 75, 105 and 120 seconds) -. Microcapsules were prepared from prepared emulsions using freeze-drying and the effect of the above factors on the changes in quality characteristics of the capsules, including the microencapsulation efficiency according to the amount of microencapsulated essential oil, the amount of phenolic compounds, and preserved antioxidants were investigated.

The results of process modeling showed that in both methods, qualitative properties of microcapsules were increased with increasing wall concentration, protein-to-polysaccharide , ratio, and ultrasonic duration. Interaction between protein to polysaccharide ratio and ultrasonic time also improved the preservation of total phenolic compounds and antioxidant capacity of Thymus vulgaris essential oil in moderate levels of variables. 28% of wall concentration, 16% protein to polysaccharide ratio, 111 seconds of ultrasonic time and 29% of wall concentration, 18% of protein to polysaccharide ratio and 87 seconds of ultrasonic time were proposed as optimum points of neural network and response surface method, respectively. Among the optimized samples, the optimum sample obtained from the artificial neural network model showed higher total phenolic content and higher microencapsulation efficiency (P<0.05).

The results of this study showed that the independent variables were effective in the microencapsulation process And the protein to polysaccharide ratio had the greatest effect on it. Also, neural network with optimal topology was very effective than response surface methodology in predicting the qualitative characteristics of microencapsulation of Thymus vulgaris essential oil due to its unique ability in processing information and modeling complex systems.

In recent years, the tendency to use antimicrobial edible film and coating has increased, which has increased the quality, safety and shelf life of food. Cheese is one of the most important dairy products that has a special nutritional value in human nutrition. UF-Feta cheese, which is a type of cheese, is contaminated by microorganisms such as coliforms, spore-forming bacteria and lactose-fermenting yeasts. The causative agent of listeriosis, Listeria monocytogenes, is transmitted through the consumption of cheese. In this study, the effect of composite edible coating based on chitosan and whey protein containing titanium dioxide (TiO2) nanoparticles and Zataria multiflora essential oil on shelf life, microbial, physicochemical and sensory properties of UF-Feta type cheese was investigated.  Furthermore, the inhibitory effect of films from coating solutions on the growth of Listeria monocytogenes was also investigated.  Chitosan, whey protein isolate (WPI) (higher than 91% protein), Zataria multiflora essential oil (ZEO), TiO2 nanoparticles, and glycerol were procured from Bio Basic (Canada), Hilmar Canada, Barij-Essence Co. (Iran), Acros Co. (USA), and Merck Co. (Darmstadt, Germany), respectively. In order to prepare the coatings, a solution of WPI and chitosan was prepared separately. Whey protein suspension (3%, w/v) was made by dispersing WPI in DDW subsequently heated at 90°C for 30 min at pH value of 8.0 and then cooled rapidly. Chitosan solution (10 g/L) was made by dispersing chitosan in 2% (v/v) acetic acid solution with constant mixing for 3 h at 60°C. Based on preliminary experiments, whey protein–chitosan suspension was made using blending two polymer suspensions at constant ratio of WPI/chitosan (70:30) and mixed magnetically for 15 min at 25ºC. In the next step, TiO2 NPs (1 and 2% w/w) were incorporated and after mixing for 15 min, glycerol (30% w/w) was incorporated to the composite suspension and again stirred for 30 min. Next, ZEO (0 and 1% v/v) was incorporated into the composites suspension and sonicated for 30 min with power of 100 W.To produce cheese samples, milk was subjected to bactofogation, pasteurization (76°C for 15 seconds), ultrafiltration and then the retentate was homogenized at a pressure of 70 bars. By adding a starter culture (10 units /1000 L), the pH of the retentate was decreased to 6.2. Then, rennet (0.004 g/ 100 g) and salt (2 g/ 100 kg) were mixed with water and added to the cheese container. Retentate was transferred to a coagulation tunnel at 37 ° C for 30 minutes to form a coagulum.  After incubation, the coating solutions were sprayed on the clot using a spray device equipped with a spray gun and packed with aluminum foil. Finally, the samples were stored at 4°C. Samples were subjected to microbiological tests (contaminating microbes and starters), physicochemical (fat, titratable acidity, pH, and moisture content, texture analysis) and sensory evaluation at different ripening periods (3 to 60 days). To evaluate the growth inhibitory of Listeria monocytogenes on the surface of cheese by composite films, pieces of cheese (23× 21× 1.7 mm) were first cut under aseptic conditions and their upper surface was inoculated with 40 μl of Listeria monocytogenes (ATCC19115) until the initial bacterial count was about 3.5 log cfu /g. The composite films placed on the surface of the inoculated cheese and stored at 4°C. Film-inoculated cheese samples were used as a control. Microbial counts were done at intervals of days 0, 3, 8, 11, 14. Data analyzed with SPSS software and means were compared with Duncan multiple range test.  The results showed that TiO2 NPs and ZEO significantly reduced total bacterial count, lactic acid bacteria and coliforms compared to control with increasing storage period. Mold and yeast colonies also increased considerably over time in the control compared to the nanoparticle-treated samples, while the While in treatments containing ZEO did not grow at all. Physicochemical analysis exhibited that the content of moisture, fat, and pH of all cheeses decreased, acidity and texture hardness increased. Sensory evaluation of UF-Feta cheeses showed that the aroma, taste and overall acceptability of the control and nanoparticle-containing coatings improved compared to the brine-treated cheese. Nevertheless, in the coating samples containing ZEO due to the negative effect of the essential oil on the organoleptic properties of cheese, consumer acceptance was significantly reduced. On the other hand, the use of composite films to inhibit the growth of Listeria monocytogenes on the surface of UF-Feta cheese at 4 °C for 14 days showed that composite films, especially films containing ZEO, had a significant effect on the reduction of the Listeria monocytogenes population. As a conclusion, composite films containing TiO2 NPs and ZEO could be applied in food packaging systems, particularly at the UF-Feta cheese packaging.

In this study the effects of gelatin edible coating and Zataria multiflora Boiss essential oil were examined on the quality of silver carp fillet during 21 days of refrigerated storage (4ºC). Treatments were included: raw fillets without any treatment (Control), treated fillets with 4% gelatin edible coating (treatment 1), fillet with gelatin coating and 0.2% Z. multiflora essential oil (treatment 2) and fillet with gelatin coating and 0.4% Z. multiflora essential oil (treatment 3). Treatment the fillet with gelatin coating Z. multiflora essential oil has significant (P

Antimicrobial packaging is a novel preservation technology that is designed base on releaseing of active agents incorporated with the packaging polymer into the packaged food or the surrounding environment for improveing the quality and food safety. Zein, water insoluble proteinof cornof corn, reported to be thermoplastic material with high tensile strength, excellent hydrophobic film, biodegradability.Zataria multiflora Boiss. (Z) is a thyme-like plant belonging to the Laminaceae family that geographically grows wild in central and southern parts of Iran. Antimicrobial activity of Z essential oil (ZEO) has been successfully tested against foodborne pathogens. Most of the studies on antimicrobial packaging mainly focused on the initial screening of newly developed films for ZEO in laboratory media and quantifying the bacterial reductions obtained during storage for different types of packaged food products. it is really important to know the variation in antibacterial activity of the agents when incorporated into the packaging film from its original activity in order to establish the levels that need to be incorporated for effective bacteria inhibition, hence The aims of the present study were to investigate the antimicrobial potential of ZEO incorporated zein film against pathogenic microorganisms inoculated in olivier saladto provide evidence of their applicability in the design of active food packaging systems.
Z was collected in the Shiraz province of Iran and extected by using clevenger type apparatus. Chemical composition ZEO was analyzed by gas chromatography.Antibacterial activity of ZEO was studied in the liquid (direct contact) and solid media (vapour phase) against Listeriainnocua and Escherchia coli . Zein powder was dissolved in a hydro alcoholic solution to obtain 16% (w/w) films forming solutions. The solution was stirred for at 80 °C using a magnetic stirrer hotplate. Glycerol (15%) was added to the solution and stirred again for 8 min at 30°Cm, then ZEO was added to the polymer solutions in 5% and 10% with respect to polymer content and stirred for 8 min. Films were obtained by casting, the film forming solutions were extended over it using an extension bar and introduced in a drying tunnel equipped with a heat of 2500 W during 20 min. Control zein films were prepared without active agent. To evaluate the efficacy of developed zein films was tested against two bacteria. Prior to the experiment, a loop of each strain was transferred to 10 ml of TSB and incubated at 37 ˚C for 18 h to obtain early stationary phase cells and100 µl of microorganism were inoculated into tubes with 10 ml of TSB. The tubes were then incubated at 37 °C for 18 h and 4 °C for 5 days. As control, zein film without active agent was also used in every experiment. Antibacterial activity of zein films containing 10% ZEO were evaluaterd for packaing of olivier salad as a real food model for 6 days, by performing serial dilutions with peptone and subsequent plating in Palcam Listeria Selective Agar and Brilliant Green Agar for ListeriainnocuaandEscherchia colirespectively. Plates were incubated at 37 °C for 48 hours.
GC–MS analysis showed thatthe major compound of ZEO was carvacrol (45.22%). The antimicrobial effects of ZEO in the vapor phase against Escherchia coliand Listeriainnocuaby using the disk diffusion methodshowed that the25 µg of ZEO produced a visible decrease in microbial density retraction zone (). No inhibition was observed with the addition of lower amounts of the antimicrobial agents, therefore 25 µg was the minimum inhibitory concentration (MIC).Activezein films containing 5% ZEOweren’t able to inhibit the growth of the two bacteria in the vapour pase.. When the concentrations of ZEO was increased to 10%, only active films with a diameter of 80 mm (50.24 cm2)provided a retraction zone () against Listeriainnocuaand E. coli. These values were indicative that incorporation of the agent in the zein films produced weaker vapor phase inhibition than its incorporation in the paper disk.The results of this studied showedthat films with 5% ZEO caused a growth reduction of 1.17 log againstListeriainnocuaand 1.14 log against Escherchia coli, while 10% ZEO produced reductions of 2.16 and 2.64 log against Listeriainnocua, Escherchia colirespectively. There was no significantdifference betweenlog reduction values of ZEO incorporated in zein films against Listeria innocuaand Escherchia coli. And also in the liquid media with increasing the concentration of ZEO in zein films, the log reduction values were increased against both bactreia. Despite of the excellent antibactrerial effect of ZEO in zein films in direct contact, bio active zein films were not effective enough for reducing the contamination of packaged Olivier.

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 (05/0> p)

Antimicrobial effect of caseinat edible film containing the essential oil of Zataria multiflora Bioss was investigated against tow gram-negative bacteria named Salmonella typhymurium (ATCC14028)، Escherichia coli O157: H7 (ATCC35218) and agram-positive bacteria Staphylococcous aureus (PTCC1431). The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) of the tested essential oil were determinate by using a broth dilution susceptibility test at 6 different concentrations (125، 250، 500، 1000، 2000 and 4000 ppm). The essential oil from Avishan Shirazi (Zataria multiflora Bioss) was most effective against S. aureus، the MIC and MBC values in the presence of E. coli O157: H7 and S. typhymurium were 500 for both of them. The antimicrobial effect of caseinate film was studing using disk diffusion method. Our result showed that the larger inhibitory diameter was belonged to S. aureus (mean=25. 17mm) mean diameters of inhibitory effect for S. typhymurium and E. coli O157: H7 were 15. 20 and 17. 62 mm respectively.

Chemical preservatives are usually used to reduce or eliminate pathogenic or spoilage microorganisms but their inordinate applications have resulted in toxigenic residuals and adverse effects on consumers، So many researches have been done to substitute the chemicals with naturally occurring compounds، especially plant essential oils. In this study log P% of vibrio parahaemolyticusATCC 43996 with different concentrations of zataria multiflora Boiss essential oil (0، 0. 0025، 0. 005، 0. 015، 0. 03 and 0. 045%) in BHI broth during incubation at 35° C for 43 days was investigated. Log P% ofvibrioparahaemolyticus was affected very significantly (p<0. 001) with all concentrations of zataria multiflora Boiss. Essential oil Vibrio parahaemolyticus wasn’t grow In any tubes of 0. 03 and 0. 045%concentrations of essential oil and maximum of log p% was calculated as -4. 241. Maximum log P% of this bacterium in 0. 015% concentration of essential oil was achievedat15th day and was 1. 761، whereas the maximum log p% for 0. 005، 0. 0025 and 0 concentrations of essential oil that was 3. 902، were achieved at 19th، 4th and 0 day. In conclusion the log P% of vibrio parahaemolyticus was decreased by increasing of zataria essential oil concentrations.

The aromatic plants are rich in essential oils characterized by a notable antimicrobial activity; for this reason, these substances can be used to delay or inhibit the growth of pathogenic or spoilage microorganisms. In this study, Log Probability percentage (Log P%) of growth of the Clostridium botulinum type A spores in Brain Heart Infusion (BHI) broth as affected by various levels of Zataria multiflora boiss essential oil (0.0, 0.03 and 0.06%), pH (7.4, 6.5) and temperatures (35, ) during 30 days of storage was evaluated. The Log p% of C. botulinum in BHI broth with 0, 0.03 and 0.06% essential oil, pH 7.4 at was 1.74 (CN = 1.82), -1.26 (CN = 1851) and – 3.26 (CN=179888) and at was 1.04 (CN = 9), -2.62 (CN = 18281) and -3.26 (CN = 179888) respectively and with 0, 0.03 and 0.06% essential oil, pH 6.5 at was 1.04 (CN = 9), -2.26 (CN = 18281) and -2.92 (CN = 82419) and at was 0.73 (CN = 18), -2.92 (CN = 82419) and -3.26(CN = 179888) respectively. Based on these results, the Log P% of growth of C.botulinum was decreased by increasing the concentration of essential oil, decreasing the pH level and temperature.