List of Articles گاز کروماتوگرافی

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  1 - The Effect of Irradiation on the Natural Volatile Compounds of Dried Mint and the Migration of Chemicals from the Packaging Materials
  F. Vedaei M. Mizani M. Mashhadi Boujar A. Gerami
  Introduction: Dried vegetables such as mint are usually prepackaged irradiated to preventthe post contamination and reduce the microbial population. This process might affect thetype and the amount of natural volatile essential oils of the product and also some ions,fre More

  Introduction: Dried vegetables such as mint are usually prepackaged irradiated to preventthe post contamination and reduce the microbial population. This process might affect thetype and the amount of natural volatile essential oils of the product and also some ions,freeradicals and low molecular weight volatile compounds might be released from the packagingmaterials due to radiolysis reactions migrated into the package and might be adsorbed ontoproduct.Materials and Methods: Dried mints, the mixtures of two species (spearmint, peppermint)were packaged in pouch of three layers of polypropylene film and were irradiated at 8, 10 and15 KGy. The changes in the natural volatile compounds of the product and those that werereleased from packaging and were isolated by distillation-extraction technique were analyzedusing gas chromatography equipped with flame ionization detector.Results: 59 different compounds were identified which might be classified into the followinggroups: a) the essential oils which were completely destroyed at three different doses(Sabinene, 7-myrcene). b) The essential oils which their concentration were increased byincreasing the irradiation dose (Trans sabinene hydrate, cis-jasmone). c) The essential oilswhich were safe in the lower doses but partially lost at 15KGy. d) Chemical volatilecompounds from polymeric packaging material which migrated into the package (tert-butylbenzene).Conclusion: The results indicated that essential oils from spearmint were more sensitive toirradiation than peppermint. To save the functional quality and also safety of prepackagedirradiateddried mint, processing dose may not exceed from 8KGy and more resistant mintspecies such as peppermint should be packaged in polymeric materials with lower sensibilityto irradiation, i.e. polyethylene terephthalate. Manuscript profile
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  2 - Optimization of Canola Oil Extraction by Ultrasound Waves and Response Surface Methodology
  F. Jalili S. M. Jafari Z. Emamjomeh M. Kashaninejad M. Ganjeh
  Introduction: Canola seed is one of the most important oil seed with high ratio of oil andhigh nutritional value and is economically recommended for cultivation and oil extraction.Extraction with ultrasound waves as a nondestructive and novel method might be employed.Th More

  Introduction: Canola seed is one of the most important oil seed with high ratio of oil andhigh nutritional value and is economically recommended for cultivation and oil extraction.Extraction with ultrasound waves as a nondestructive and novel method might be employed.Therefore the aim of this research is optimization of extraction of canola oil by ultrasoundwaves and RSM.Materials and Methods: In this project, Response Surface Methodology was employed foroptimization of canola oil extraction by ultrasound waves using hexane andhexane/isopropanol as solvents by the ratio of 3:2 (v/v). The influence of extractiontemperature in the range of 35, 45 and 55℃, ultrasound treatment time for 30, 60 and 90minutes and ratio of solvent to canola in three levels of 5, 10 and 15 ml/g were analyzed byBox-Behnken Design (BBD) based on extracted oil percent. The fatty acid compositions ofthe extracted oils using ultrasound-assisted method and soxhlet method employing gas liquidchromatography were determined and compared.Results: According to the high values of correlation coefficients of selected models optimizedfor hexane solvent extraction methods (R2 =0.93) and hexane-isopropanol solvent mixture(R2 =0.97) and no significant lack of fit tests (P>0.05) selected models might be useful topredict the extraction percentage of canola oil.Conclusion: The results showed that the optimum conditions for canola oil extraction byhexane (22.39 %) and combined hexane/isopropanol (30.66 %) were respectively atultrasound treatment times of 69.5 and 87 minutes, temperatures of 55 and 55 ℃ and ratio ofsolvent to canola of 6.39 and 9.12 (%v/w). Extraction efficiency was significantly improvedby ultrasound as compared to the soxhlet extraction. Fatty acid compositions of the canolaoils were not significantly affected by the application of ultrasound (P> 0.05). Thereforeultrasound might be regarded as a simple and rapid method to improve the extraction of oilwithout affecting the quality of the fatty acids present. Manuscript profile
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  3 - Assesment of Fatty Acid Composition in Industrial Pasturized Cream in Southern Part of Iran
  M. H. Naji F. Shahidi S. A. Mortazavi A. Kochaki H. Skandari
  Introduction: Cream structure consists of various quantities of short chained fatty acids. Some of the fatty acids are branched and some are conjugated and some are nonconjugated with even or odd carbon numbers. A number of unusual fatty acids namely cyclohexyl fatty ac More

  Introduction: Cream structure consists of various quantities of short chained fatty acids. Some of the fatty acids are branched and some are conjugated and some are nonconjugated with even or odd carbon numbers. A number of unusual fatty acids namely cyclohexyl fatty acids among others have been identified. Materials and Methods: In this research cream with 30% fat content was produced, pasteurized and packed from the milk delivered to three plants on southern part of Iran. Samples were collected every three hours after production and three and six days later and investigated regarding the fatty acid composition and profile using gas liquid chromatography. Results: The results indicated that the fatty acid composition of the samples differentiated from each other based on the diet and feed consumed. However differences were observed among some fatty acids namely palmitic, conjugated and tran acids. Conclusion: The fatty acid composition of creams indicated differences at p ≤ 0.05 level. This study showed that among the species, composition of fat and fatty acids are not constant and uniform. Manuscript profile
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  4 - Survey on residuals of Fenpropathrin in greenhouse cucumber
  B. Rafiei S. Imani M. Alimoradi H. Shafiee Sh. Khaghani S. R. Bastan
  Widespread use of chemical pesticides in agriculture production has brought up concerns regarding the accumulation of residues in food and agricultural environment and endangering human health and ecological balance. Cucumber is of a fresh use vegetable with high consum More

  Widespread use of chemical pesticides in agriculture production has brought up concerns regarding the accumulation of residues in food and agricultural environment and endangering human health and ecological balance. Cucumber is of a fresh use vegetable with high consumption in Iran and has more contamination due to short period between spraying and harvest time. This experiment were carried out to investigate the residues of Fenpropathrin (EC 10%), in a cucumber cultivar in greenhouse (Storm). Cucumber plants was sprayed at recommended doses (2 g/lit) and Samples were collected 1 hour, 1, 3, 5, 7 & 10 days intervals after treatment. Further purification achieved using a silica solid-phase extraction (SPE) cartridge and pesticides residues were analyzed using GC-MS.Result showed that Fenpropathrin levels below maximum residue level (0.5 mg/kg) were detected 3 days after application and no residues were detected on the 10th day. Manuscript profile
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  5 - Determination of residue of Deltamethrin on greenhouse cucumber
  B. Rafiei S. Imani S. R. Bastan
  Due to the extensive use of pesticides in all fresh consumptive vegetables and fruits, it is important to detect the residues of these compounds. Due to short period between spraying and harvest time, cucumber can show a higher level of contamination. This experiment wa More

  Due to the extensive use of pesticides in all fresh consumptive vegetables and fruits, it is important to detect the residues of these compounds. Due to short period between spraying and harvest time, cucumber can show a higher level of contamination. This experiment was carried out to investigate the residues of Deltamethrin (EC 2.5%), in a Storm cultivar of cucumber in greenhouse. Plants were sprayed at recommended doses (0.5 g/lit) and, samples were collected 1 hour, 1, 3, 5 & 7 days intervals after treatment. Pesticides residues were analyzed using GC-MS. Results showed that Deltamethrin levels below maximum residue level recommended by codex (0.2 mg/kg) were detected 5 days after application and no residues were detected on the 7th day. The average of recovery from fortified samples with 0.5 ppm of Deltamethrinobtained 91.3%. Manuscript profile
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  6 - Comparison of physicochemical properties and fatty acid profile of salicornia oil with iranica, persica Akhani and persplitana varieties
  Behzad Rahnatzadeh Simin Asadollahi Leila Nateghi
  AbstractRecently, with the growth of public knowledge, people desire to consume oils that in addition to providing energy and flavor, is also beneficial to health. It has been reported that 96% of the oil consumed in Iran is imported, while the potential for growing cro More

  AbstractRecently, with the growth of public knowledge, people desire to consume oils that in addition to providing energy and flavor, is also beneficial to health. It has been reported that 96% of the oil consumed in Iran is imported, while the potential for growing crops similar to salicornia that can grow in saline soils and habitats in Iran is significant. in this study, salicornia plant was used as an oil source in the production of blend oils. In this study ,Physicochemical properties assessment of salicornia plant (fatty acid profile, acidity, refractive index, iodine, density, soap number, percentage of extracted oil, oxidative stability, peroxide) in three varieties of salicornia variety )Persica, Salicornia perplitana and Iranica) were examined. The results showed that the amount of oil extracted efficiency in Salicornia varieties was significantly(p≤ 0.05) , respectively of iranica 001/0± 9/15 % , persplitana  002/0± 700/5% and persica Akhani 002/0± 800/8% and in gas chromatography test 10 types of fatty acid profiles in extraction oils as well as formulated oils were analyzed. Among these, linolenic fatty acids varieties was significantly(p≤ 0.05) ,  in different varieties were iranica 005/0± 946/2% , persplitana 010/0± 230/3and persica Akhani 005/0± 133/42 , respectively. Manuscript profile
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  7 - Comparative investigation of the effects of antifungal activities of some essential oils on Alternaria alternata fungus as a causal agent of tomato early blight disease
  hassan mahdavikia Abdollah Ahmadpour
  Tomato early blight disease, caused by the fungus Alternaria alternata, is one of the most devastating diseases for the crop in Iran and worldwide. Recent studies have shown that some secondary metabolites of medicinal plants are effective in preventing the growth of fu More

  Tomato early blight disease, caused by the fungus Alternaria alternata, is one of the most devastating diseases for the crop in Iran and worldwide. Recent studies have shown that some secondary metabolites of medicinal plants are effective in preventing the growth of fungi and are a good alternative to the use of chemical pesticides. In the present study, ten medicinal plants including Eucalyptus sp., Thymus vulgaris, Mentha piperita, Mentha longifolia, Mentha aquatica, Satureja hortensis, Achillea millefolium, Foeniculum vulgare, Anethum graveolens, and Trachyspermum copticum were collected during 2016-2017. Their essential oils were extracted using Clevenger apparatus, and GC-MS device was used to identify the essential oil compounds. Antifungal activity of essential oils was assayed through the inhibition of fungal colony growth at five concentrations of 0, 200, 400, 800, and 1200 ppm in mixing with potato dextrose agar medium with three replicates. The findings revealed that fungus colony growth was inhibited with increases in essential oils concentrations, and there were significant differences among different essential oils. Essential oils of Satureja hortensis, Trachyspermum copticum and Thymus vulgaris in 800 and 1200 ppm and Anethum graveolens in 1200 ppm demonstrated the highest effect on fungus colony growth. This study found that Carvacrol, Thymol, Para-cymene, and Gamma-terpinene ingredients tend to have the highest antifungal effects. Manuscript profile
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  8 - Identification of fatty acids composition in fresh and frozen silver carp (Hypophthalmichthys molitrix) for determination of its shelf life at -18ْc
  A. R. Najafi N. Beheshtiseresht
  In this work, after extraction and methylation of the lipids form silver carp tissues in fresh and frozen stages and their changes during 6 months in -18°C, identification of fatty acids of the samples were done by gas chromatography (Shymatsv HSSA4). Results of thi More

  In this work, after extraction and methylation of the lipids form silver carp tissues in fresh and frozen stages and their changes during 6 months in -18°C, identification of fatty acids of the samples were done by gas chromatography (Shymatsv HSSA4). Results of this investigation showed that amounts of unsaturated and saturated fatty acids in fresh samples were 70/95% and 28/95% respectively. In fresh tissues the amount of oleic acid was 30/16%, and Iino leice amount was 11/44%. Alpfa – lino lenice acide was 4/41%, Gcosapanethanoic was 6/42% and docosa hexanoic was 6/15%. These were the most important poly-saturated fatty acids. But after six months of freezing at -18° c the amounts of these fatty acids decreased to 10/02%, 3/18%, 2/97%, 1/05% and 1/02% respectively. Results showed a decrease in freezing condition of fatty acids. Based on these results, the best storage for frozen fish in -18°C is four months. These results were subjected to tests of Tukey and Analysis of Variance and were significant at the level of 95%.   Manuscript profile
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  9 - Isolation of fluorene degrading microorganisms from sediments of the Southern Caspian Sea Coasts and evaluation of their bioremediation potential
  Ehteram Sadat Rahimi Jamshid Fooladi gholamhossein ebrahimipour Mohammad Reza Soudi Tayebeh Fooladi
  Background and Objectives: Polycyclic aromatic hydrocarbons are one of the most important environmental pollutants. Bioremediation using microorganisms is a cost-effective and safe method for the removal or conversion of these pollutants to less toxic substances. This s More

  Background and Objectives: Polycyclic aromatic hydrocarbons are one of the most important environmental pollutants. Bioremediation using microorganisms is a cost-effective and safe method for the removal or conversion of these pollutants to less toxic substances. This study aimed to isolate and introduce fluorene-degrading microorganisms from the southern coast of the Caspian Sea. Materials and Methods: The mixed microbial culture enrichment and isolation was done in salt-based culture medium containing fluorene. The qualitative analysis of fluorene degradation in the solid basal salt medium was investigated. The rate of fluorene removal by the isolated mixed microbial culture was also determined using gas chromatography in a liquid salt base medium. The molecular identification of the fungal and bacterial isolates was performed using the sequential analysis of the ITS protected region and 16S rRNA sequencing, respectively. Results: The mixed microbial culture including bacterial isolates (belonging to the genus Pseudomonas, Acromobacter, Chryseobacterium, Microbacterium, and Rhodococcus) and fungal isolate (belonging to the genus Fusarium) was enriched and isolated. Chromatographic analysis showed that the mixed microbial culture was able to degrade 87% of fluorene (200 mg / l ) in a basal salt medium at 30 °C, pH 7 and 7 days of incubation. Conclusion: According to the results, the mixed microbial can remove a large amount of fluorene from the basal salt medium under the mentioned conditions and it is possible that under a similar situation, it can remove a large amount of fluorene from the contaminated area through bioremediation.   Manuscript profile