فهرست مطالب نادیا احمدی

New packaging is not only responsible for including and protecting food from external factors, but also has other benefits that include increased storage time, prevent spoilage and nutrient loss, and determine the shelf life of food. Increased demand for foods with fresh properties, reduced synthetic additives and preservatives, low environmental degradation and safety, have led researchers and industries to develop milder processing technologies and more eco-friendly packaging solutions. In this regard, the use of nano-emulsions to improve food packaging performance is compatible with sustainable development and new functions in conventional coatings and films. Nano-emulsions that have unique optical stability and rheological properties, including: protection, encapsulating and delivery of hydrophobic bioactive and functional compounds (including natural preservatives such as: plant essential oils, nutraceuticals, vitamins, colors, and flavors, surfactants (including naturallyoccurringproteins and carbohydrates), are used to design nano-emulsions with the desired food grade for packaging applications. In this paper, nano-emulsions in biopolymer matrices used in food packaging are investigated as well as their potential antimicrobial activity against foodborne pathogens.

 

CoQ10 is a lipophylic natural antioxidant with fundamental role in mitochondria bioenergetics. The positive effect of CoQ10 in therapy of many diseases is due to its antioxidant and bioenergetics properties. Reduction of endogenous synthesis of CoQ10 by the ageing, insufficient amount in the food and several health benefits of CoQ10 have led to food fortification. The objective of this study was to microencapsulate CoQ10 by complex coacervation method and determinate of optimum mixture component (β-lactoglobulin (β-lg), Arabic Gum (AG), Oil containing CoQ10 and water) to achieve maximum value of microencapsulation efficiency (ME) and payload. Due to temperature sensitive characteristic of CoQ10, Gelatin was replaced with β-lg and combination of β-lg and AG were used to microencapsulation of Oil containing CoQ10.

At first CoQ10 powder and olive oil were poured in opaque tube and stirred in incubator shaker for 24h. Then solutions of β-lg and GA were prepared at 1-4% (w/w), by dispersing the required amount of them in deionized water and microcapsules were formed by adding oil phase containing CoQ10 to the β-lg solution and preparation of emulsion, adding the GA solution and adjusting pH to 4. After separation of microcapsules freeze dryer was used to dehydration of them, and Morphology of CoQ10 microcapsules was examined using a Scanning Electron Microscope (SEM) and an optical microscope. The particle size and the particle size distribution of moist microcapsules were determined using a particle size analyzer. In the next stage it was used from n-hexane to extracting oil and extracted oil was dissolved in 1,4-dioxane and analyzed by a high performance liquid chromatography (HPLC) system, and microencapsulation efficiency was calculated for microcapsules before and after freeze drying. At the end the effect of oven drying and defrost on microencapsulation efficiency was studied for 5 formulations.

ME values before drying for all formulations except one sample (containing: 4%β-lg, 4%AG, 5%Oil and 87% water) were in the range of 94.05-99.01%. Variation in ME and payload values after freeze drying was in the range of 34.91-92.45 and 24.78-83.75%, respectively and sample containing 2.5% (w/w) β-lg and 2.5% (w/w) AG and 5 % (w/w) oil obtained the highest ME value, an homogeneous particle size distribution and had a smooth and free of pores surface.

Based on the results, formulation containing 2.5% (w/w) β-lg and AG and 5 % (w/w) oil can be successfully used to microencapsulation of CoQ10

Increased environmental demand and decreased ability of an individual for responding to them raises mental pressures and leads to job burnout. Since job burnout has never been evaluated in nurses working in hospitals affiliated to Mazandaran University of Medical Sciences, the present study was carried out with the aim of evaluating job burnout rate in nurses working in emergency departments (EDs) of hospitals affiliated to Mazandaran University of Medical Sciences.
The present cross-sectional study included all of the nurses working in EDs of 3 teaching hospitals affiliated to Mazandaran University of Medical Sciences using consecutive sampling. The standard Maslach and Jackson questionnaire was used for assessment of job burnout. SPSS version 20 was used for analyzing data.
A total of 93 nurses with the mean age of 32.48 ± 8.1 were evaluated (72% female). The highest frequency belonged to 20-30 years age range (48.9%) and 5-9 years job experience (39.3%). Based on the results of rotated factor matrix, the load of emotional exhaustion, lack of personal success, and depersonalization in prevalence of job burnout was 7.42, 4.89 and 2.45 respectively. Mean intensity of emotional exhaustion was 33.19 ± 14.35 (0 –54), depersonalization was 4.91 ± 5.27 (0 –20) and lack of personal success was 29.58 ± 8.57 (8–45).
Based on the findings of this study, all the nurses working in the evaluated EDs showed degrees of job burnout. The highest load in prevalence of job burnout belonged to em otional exhaustion, lack of personal success, and depersonalization, respectively. The hospital in which they worked, age, sex, and job experience did not significantly affect the intensity of job burnout.

Crude vegetable oils contain some quantities of Phospholipids. The highest concentration of phospholipids is usually found in crude soybean oil. The presence of phospholipids in the crude and refined oils create undesirable effects on the quality and quantity of the oil during refining operations or use by the consumer. However، If phospholipids are extracted properly from the oil they could have valuable applications in many food systems. There are limited numbers of oil plants that extract soya lecithin in Iran and separate phospholipids from soyabean oil and distribute this valuable by product as soya Lecithin in the market. In this study two dimensional thin layer chromatography has been applied to measure the extracted phospholipids from five varieties of soyabeans both qualitatively and quantitatively. Five varieties of soybean cultivated in Iran (Sahar، Sims، Williams، Gorgan3 and Hill) have been studied. The isolated phospholipids for each variety was further separated into their individual constituents using two dimensional thin layer chromatography method and the concentrations were calculated on the basis of the four main phospholipids present in soybean oil that included; phosphatidyl choline، phosphatidyl ethanolamin،phosphatidyl inositol and phosphatidic acid. The amount of total phosphatidies as percent were 1. 57، 1. 61، 1. 72، 1. 53 and 1. 71% in Sahar، Hill، Williams، Gorgan and Sim varieties، respectively. Conclution: The results showed that the highest concentration of phosphatidyl choline and phosphatidyl inositol were found in Williams variety and the highest amount of phosphatidyl ethanolamin and phosphatidic acid were found in Sahar and Sims varieties.

Batch adsorption experiments were carried out for removal of basic dye, namely Basic Yellow 28 (BY 28), from synthetic wastewater sample of textile’s company, using sodium dodecyl sulphate coated magnetite nanoparticles (SDS-Fe3O4 NPs). The effects of various experimental parameters (e.g. initial pH, SDS amount, ion strength) were examined and optimal experimental conditions were obtained. The results showed that adsorption process onto the adsorbent is very fast and nearly 30 min of contact time was found to be sufficient for the dye adsorption to reach equilibrium. Equilibrium isotherm data were analyzed according to Langmuir and Freundlich equations. The characteristic parameters for each model have been determined. The Langmuir isotherm gave the best correlation for the adsorption of the BY 28 onto the adsorbent. On the basis of the Langmuir analysis, the maximum adsorption capacities were determined to beand 140.8 mg g-1. Also, regeneration studies showed that Fe3O4 NPs can be regenerated and reused at least for six times.

This study performed in Caspian Sea in order to estimate nutrients nitrate factors (pH, temperature and salinity) from April to October 2008. Sampling was done in southeast Caspian Sea in five transects in 45 stations on surface water, 5 and 10 meter depths based on national standard. The mean concentration of nitrate was 5.37, 8.87 and 0.47 mg/l in first transect, it was 5.81, 9.98 and 0.76 mg/l in second transect, and 5.31, 11.76 and 0.71 mg/l in third transect, 5.40, 11.38 and 0.69 mg/l in fourth transect and 14.28, 14.89 and 2.09 mg/l in fifth transect. The concentration of nitrate was increasing from Salman Shahr to Amirabad. There was significant differences in nitrate concentration in transects (P<0.05), but the other parameters were not significantly different among surface, 5 and 10 m waters (P>0.05).

Pomegranate is an attractive deciduous and somewhat thorny large shrub or small tree (Punica granatum L.) belonging to the family Punicaceae, native to semitropical Asia (Iran) and naturalized in the Mediterranean region in very early times. The edible part of the fruit contains considerable amounts of sugars, Vitamins, Polyphenols, Polysaccharides and Minerals. The physico-chemical properties of 8 Pomegranate varieties (collected from different provinces of Iran) and corresponding juices where investigated. The major minerals index (Mn,Cu,Fe,Zn,Pb,Cd,K,Na,Ca and Mg) were determined by Atomic absorption spectrophotometer. Acidity index was determined by potansiometer, SCC index was determined by refract meter and pH index was determined by pH meter. vitamin C index were determined by titrimetric method and total sugar was determined according to AOAC method. It was perceived by using an atomic absorption spectrophotometer, the quantities of K, Na, Ca and Mg were significantly higher than other minerals (Mn, Cu, Fe, Zn, Pb and Cd) in the fruit juices. In addition the average concentration of Vitamin C, TA, SSC, pH and acidity were respectively 0.25 mg/100g, 13.3g/l, 16.8°B, 3.7 and 0.97. The mineral contents were generally as the same that those established in Iranian national standardthe and codex standard for pomegranate. The study emphasizes that pomegranate fruits can be a good source of nutrients.