hoda jafarizadeh malmiri

Biodegradable films containing poly (lactic acid) (PLA) and starch with three ratios of 90/10, 80/20 and 70/ 30 were prepared and analyzed using FT-IR, FESEM, XRD, EDS and TGA. Results of FT-IR and FESEM indicated that highest amount of starch (30 %) was lead to fragile and less strength of PLA/Starch films. Results indicated that by addition of 5% maleic anhydride (MA) and ZnO NPs to the film formulation, adhesion between the two phases was significantly (p < 0.05) increased Furthermore, by increasing amount of ZnO NPs from 1 to 5% into the film formulation, amorphous structure of the film was significantly (p < 0.05) increased, and the films containing 1 and 5% ZnO NPs had crystal size of 34.14 and 28.4 nm, respectively. Results indicated that by increasing the amount of ZnO NPs in the film formulation from 1 to 5 %, its thermal resistance increased and weight loss decreased from 95.13 to 88.19 %, respectively. Furthermore, degradation percentage of the films decreased from 77.3 to 69.39%, respectively, after one month. Results indicated that film, based on PLA/Starch/MA/ ZnO NPs with ratio of 80/20/5/5 had carbon, oxygen and Zinc with weight percentage of 70.3, 25.1 and 4.6%, respectively.

Silver nanoparticles (Ag NPs) as a new antibiotic generation were green produced using Arabic gum, as capping and stabilizing agents, under microwave heating. Results indicated that using 0.5 mL of 3 mM silver nitrate solution and 0.5 mL of Arabic gum solution (1 % W/V), and microwave heating time of 150 s, Ag NPs were fabricated minimum broad emission peak (λmax) and maximum concentration of 424±2 nm and 25±2 ppm, respectively. Transmission electron microscopy and dynamic light scattering analyses specified that the fabricated spherical Ag NPs using these optimal synthetic parameters had particle size, polydispersity index and zeta potential values of the 89 nm, 0.238 and +50 mV. Furthermore, antibacterial test indicated that diameters of the formed clear zones around the holes having Ag NPs were 13 and 15 mm, toward Escherichia coli and Staphilococcus aurous, respectively. Antifungal assessment also shown that synthesized Ag NPs could strongly inhibit the growth of Aspergillus flavus mycelia in the plate during incubation for 7 days. Synthesized Ag NPs using the obtained optimum conditions can be widely used in the food, pharmaceutical and cosmetics areas, due to those high antimicrobial activities.

The plant-based extract can be used to synthesize silver nanoparticles (Ag NPs) as a reducing agent. In the present study, Oregano leaves’ extracts were extracted using ethanol to synthesize Ag NPs. The effects of different parameters such as the processing time, temperature, and stirring rate on the mean particle size, concentration, and zeta potential of the synthesized Ag NPs solutions were optimized using Response Surface Methodology (RSM). At the optimum condition, which includes processing time (30.48 min), temperature (70 ºC), and stirring rate (370.530 RPM), Ag NPs were obtained with 33 nm of the mean particle size, 76.109 ppm of concentration, and +17.2 mV of zeta-potential. In this condition, Ag NPs displayed high antibacterial activity against Gram-negative and Gram-positive bacteria. In addition, the maximum antioxidant activity of 11.7% was obtained at optimum synthesizing conditions.

The purpose of this research is extracting propolis using the methods of soaking in 20% and 70% ethanol and the effect of ultrasound in 20% ethanol, and evaluating its physicochemical, antioxidant and antimicrobial properties as a natural preservative used in the food industry. The physicochemical properties, the amount of phenolic and flavonoid compounds, the antioxidant and antimicrobial properties of the extracts were measured. The results showed that most of the number of phenolic compounds (94.19 mg/g), flavonoid (89.46 mg/g) and antioxidant property by DPPH method (92.63%) in ultrasonic extracts. And the lowest number of phenolic compounds (87.85 mg/g), flavonoid (82.20 mg/g) and antioxidant property (85.87%) are in the method of soaking in 20% ethanol. Also, the results of the investigation of the antimicrobial property by the diffusion ability method from the well showed that the most sensitive bacterium was Staphylococcus aureus (20 mm) in front of the ultrasonic extract. Regarding the ability of Pseudomonas aeruginosa bacteria, there was no significant difference between the extracts (p<0.05) and none of the extracts had antibacterial power against Pseudomonas aeruginosa bacteria. The highest ability of Candida albicans (36 mm) was with ultrasonic extract, and in the investigation of the growth of Aspergillus niger after spraying for 8 days, the lowest growth rate was obtained with ultrasonic extract (9 mm) and then 70% ethanol extract (10 mm). Based on this, the amount of phenolic, flavonoid, antioxidant and antimicrobial compounds was 70% more than the 20% ethanol extract, and in the ultrasound, method based on Hurdel technology, a large number of active compounds were found in the 20% ethanol solvent in a short period of time.

Fruit and vegetable juices, with antioxidants, vitamins and minerals, are considered to be popular and healthy beverages, which increase health. Mixing of juices is one of the methods for improving the nutritional quality of the final product, which by this method improves the content of bioactive compounds according to the type and quality of fruits and vegetables. The aim of this study was to produce fresh and healthy juice from fruit and vegetable blends, and to study organoleptic and physic-chemical properties with consumer acceptance. Different formulas of the juices composition were prepared in five types and stored in the bottles for 9 days in the refrigerator for physicochemical analysis and sensory evaluation. The effect of fruit juices storage time of 3.6 and 9 days on pH, acidity and ascorbic acid content was investigated. The nutritional value and high antioxidant properties of mixed juices indicate that they can be used as sources of rich bioactive compounds. Except for the compound formula 1 ( carrot 120 gr, orange 130 gr, flaxseeds 15 gr, honey 10 gr, ginger 10 gr, water 115 gr), the rest of the beverage compounds were commercially available in terms of public acceptance. Combined juices this study is recommended for people with obesity, hypertension, cancer and cardiovascular diseases, as they play a significant role in the prevention of these diseases. The formulated compounds from fruits and vegetables are sources of calcium, magnesium, iron and antioxidants (ascorbic acid, flavonoids, total phenols). Therefore, the use of such fruit juices protects the human body from several diseases.

Snacks such as puffed corn are food products that have high consumption particularly by children. But unfortunately, these products have high calorie and low amount of useful components. One way to enhance their nutritional value can be using fruit powders in their formulation. In this study, barberry fruit powder (BFP) being as a rich source of bioactive components, was used in the formulation of puffed corn at levels of 0 (control sample), 2.5%, 5%, 7.5% and 10% and in the quality properties were analysed in the finished product. Results showed that antocyanins (from 3 to 110 ppm) increased by increasing the BFP, but pH (from 5.5 to 4.1) and oil content (from 25.5 to 19.5%) and water activity (from 0.8 to 0.65) were decreased. Also, samples containing BFP were in standard range. In addition, organoleptic tests of samples showed that sample containing 5% of BFP obtained the highest score and in higher amount of BFP the scores were decreased. In conclusion, the obtained results showed that there is possibility to produce puffed corn containing BFP which can be a new product with suitable nutritional properties and healthful in the market.

Bioethanol is used as substitute fuel to reduce dependency on fossil fuels, ensure energy security and reduce the negative impact of fossil fuel consumption to the economy and the environment sugar beet Malass are very good raw materials for ethanol production due to their content of fermentable sugars, which can be directly used for fermentation without any modification. Previous studies have shown that Selenium enriched yeast (Se-yeast) is a good carrier for selenium biotransformation. Therefore one of the most economical sources of organic selenium is yeast grown in a selenium-enriched culture medium. The main objectives of the present study were to evaluate the effect of selenium on the yield of bioethanol production and achieve the bioethanol with highest concentration, and compare the concentration of produced bioethanol, using S. cerevisiae, at obtained optimum condition with and without using selenium. For preparation of the growth media molasses was sterilized. After addition of the 0.3 g of the S. cerevisiae strain, SFO6 for the nutrition in molasses as fermentation media was enriched by addition of 500 and 250 ppm of (NH4)2HPO4 and urea, respectively and different amount of selenium (0, 5, 10, 15, 20 and 25 μg).The effect of different amounts of selenium and molasses on bioethanol yield was investigated. Obtained results revealed that maximum bioethanol concentration (80g/L) was achieved using 20μg selenium and molasses with 25°Bx. S. cerevisiae is a good option for increasing bioethanol production efficiency from selenium-enriched sugar beet molasses

Simulating of operating conditions for different processes is a positive step towards saving time and cost. In the present study, Thyme essential oil nanoemulsions using tween 80, as emulsifier, under sub-critical water conditions (Temperature above 100 ° C) were prepared according to the results of the simulation of operating conditions using the COMSOL Multiphysics software and their physical properties were evaluated. The simulation results showed that heating at temperature of 120 ° C up to 120 minutes, could not provide sub-critical water conditions, and the Thyme essential oil nanoemulsions were not formed. However, oven heating of sealed container containing Thyme essential oil nanoemulsions, at same temperature for minimum 120 min, indicated that the temperature of the formed nanoemulsions was ranged in108 to 111 ° C, which that was completely satisfied sub-critical water temperature condition. Physico-chemical properties of Thyme essential oil in water nanoemulsions were analyzed using DLS, FTIR and TEM. Obtained results indicated that the prepared nanoemulsions under sub-critical water conditions had particle size, polydispersity index and zeta potential of 33 nm, 0.221 and -13.5 mV, respectively. Morphological attributes of the formed nanodroplets indicated that nanodroplets with spherical shape were formed which that revealed their highest thermodynamic stability.