Purpose: Due to the potential industrial and therapeutic applications of the yeast exopolysaccharides (EPSs), there has been an increasing demand to assess these biopolymers with improved characteristics. This study aimed to characterize the EPSs from Rhodosporidium babjevae (ATCC 90942 and IBRC-M 30088) as well as to evaluate their possible antioxidant, emulsifying and antiproliferative activities. Methods: Rhodosporidium babjevae was cultured for 5 days and following isolation of supernatant, EPSs precipitated with adding of cold absolute ethanol and freeze-dried. The EPSs chemical structure was determined by FT-IR, SEM, HPLC-SEC and GC-MS. Additionally the solubility, water holding capacity and emulsifying activity of EPSs were evaluated. In vitro, antioxidant activity was investigated against DPPH, superoxide and hydroxyl radicals. Finally the EPSs consequence on the cell proliferation of human breast adenocarcinoma (MCF-7) and Madin-Darby canine kidney (MDCK) cell lines was evaluated by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) test. Results: R. babjevae excreted 1. 6± 0. 2 g/L of the EPSs. The EPSs had three fractions with molecular weights of 1. 02 ×10 6, 5×10 5 and 2×10 5 Da. Mannose and glucose were found as the main monosaccharides of the EPSs (84: 16 mol%, respectively). The EPSs exhibited emulsifying activity on sun flower oil. The scavenging activities were found to be dose-dependent and higher than hyaluronic acid. Significant difference among the EPSs treatments on the proliferation of MCF-7 and MDCK cell lines was not observed (P > 0. 05). Conclusion: These results show the interesting potential of the EPSs from R. babjevae as biocompatible compounds for using in food and pharmaceutical fields.

One of the common esterification methods to develop functional properties such as emulsification, is to use octenyl succinic anhydride (OSA). Therefore, in this research, some of the functional properties of OSA modified Persian gum (whole, soluble and insoluble fractions) in the optimal conditions with high degree of substitution were investigated. The FT-IR spectroscopy confirmed the formation of carbonyl groups in OSA treated gums (PG and soluble fraction). In addition, our findings on emulsifying properties demonstrated that modification of PG and its soluble fraction by using OSA improved their emulsifying properties 6 and 4 times in comparison to their untreated counterparts, respectively. Moreover, the microstructure of emulsions contained high number of small particles and longer physical stability. Furthermore, rheological investigations showed that flow behavior as well as apparent viscosities were reasonably different than untreated PG and its soluble fraction.

Ferula gumosa Boiss is one of the natural plants of Iran whose exudates (Barijeh) can be used in food industry. In the present study the properties of the gum extracted from tubers of Ferula gumosa were examined. For this purpose, gum was extracted from crude exudates by alcoholic extraction with 90% (v/v) ethanol. The purity of gum was relatively high, and it was composed mostly of polysaccharide. Soybean oil emulsions (10% w/w) were prepared using gum with concentration from 0.2 to 1.0 % (w/w). Surface tension, interfacial tension and creaming measurements were performed for all emulsions. Particle size measurements, light microscopy observations and theological studies were performed for 1.0 % gum emulsion. The purified gum was found to reduce surface tension and interfacial tension of emulsions. Although particle size distribution measurements showed a slight change in particle size pattern after two month, mean diameter of particles remained constant. The creaming tests confirmed a comparatively good overall stability over a period of two months. The rheological measurements showed the shear thinning nature of emulsions prepared with the Barijeh gum. The emulsion stability was attributed to the surface adsorption mechanism.

Charkhak (Launaea acanthodes) is one of the most common species of medical herbs in central Iran. In this study, the gum was extracted by alcoholic extraction method with 90% ethanol that the yield percentage was 40.4%. Then, emulsifying properties of the extracted gum were investigated. To do so, soybean oil emulsions (10% w/w) were prepared using 1, 2, 4, and 6% gum. Following tests were done for all emulsions: surface and interfacial tension, stability testing, particle size distribution, observing by light microscope and viscosity of the emulsion. Altogether, it was illustrated that polysaccharide efficiency of Launaea acanthodes gum is higher than other national gums in Iran. According to the results, increasing the gum concentration in emulsion led to decrease in surface and interfacial tension but an increase in viscosity. The particle size distribution reduced with increasing the concentration of gum in emulsion. Moreover, the gum had good overall stability in the past two months.

Recently, the demand of consumers to use vegetable proteins as a substitute for animal proteins has been increased. Cereal bran contains protein, fiber sources, minerals and antioxidants. In this research, optimization of emulsifying capacity and emulsion stability of wheat bran protein was performed using response surface method (RSM), central composite design (CCD) and Design Expert software. The design included the independent variables of centrifugation time (20-60 minutes), centrifugation temperature (4-20°C), alkaline pH (8-12) and 10 replications at the central point. Centrifugation time had a significant effect on emulsion stability (P<0.05); but it had no significant effect on the capacity of emulsion formation (p>0.05). Centrifugation temperature changes had a significant effect on the amount of emulsion formation capacity and stability (P<0.05). Changes in alkaline pH had a significant effect on the amount of emulsion formation capacity and stability (P<0.05). Evaluation of the optimal conditions suggested by the software for the formation capacity and stability of the emulsion were not significantly different from the test results (p>0.05). The results of this research showed that wheat bran protein as a vegetable protein source has a high potential to be used as an emulsifier in the food industry.

123Introduction: Pectin is a structural heteropolysaccharide in the cell wall of plants and after extraction it is used as a gelling agent in food products. The main sources of pectin are apple and citrus peel, but pectin from various sources, may have unique properties. Therefore, research is ongoing to find new sources of pectin and study their properties. The conventional extracting method is performed using a solution of mineral acids, this process is time-consuming and has some disadvantages in terms of quantity and quality of extracted pectin. It is very important to look for new methods or modifications to produce pectin with high efficiency and quality. One of the new methods is ultrasonic extraction, which has been studied extensively. The aim of this study was to optimize and quantitative and qualitative evaluation of pectin extraction from tomato pomace as one of the major wastes of industries in Iran. Also Ultrasound was used as a new and effective method for extraction of pectin. Ultrasound assisted extraction (UAE) of pectin from waste tomato pomace was investigated and optimized using Box– Behnken response surface design. The individual and interactive effect of process variables (pH, temperature, extraction time and power density) on the pectin yield and purity was studied. Also, the degree of esterification, intrinsic viscosity and emulsifying properties were determined on optimized conditions. Materials and methods: Tomato pomace was supplied from ATA Company located in Tehran, Iran. It was dried at 60 ° C for 36 hours. Then was milled and sieved by 60 mesh size screen. Fatty acids and pigments were removed from tomato pomace and again dried. The obtained powder stored at ambient condition for further uses. Ultrasonic device (Ultrasonic Technology Development Company, IRAN and 400 w, 20 KHz) with 12 mm probe and double-shell tank was used to carry out the extraction. Response surface methodology (RSM) was carried out to study the effect of pH (1. 5-2. 5), temperature (60-90℃ ), extraction time (6-30 minutes), and power density (0. 15-0. 3 W/ml) as input variables on the yield and galacturonic acid (GalA) content as the output (responses). GalA content was determined by colorimetric method (titration), using the 3, 5-dimethylphenol as reagent and D-galacturonic acid as standard. To determine the degree of esterification, titration method was used. The intrinsic viscosity of pectin was determined by applying a capillary viscosimeter (Cannon Instruments Co., No. 150, Cannon-Fenske, Germany; k = 0. 04137 mm2/s2). Emulsifying properties of pectin extracted at the optimal point were investigated at three levels of pectin concentration %0. 25, % 0. 5 and %1. Results and discussion: The experimental data obtained were analyzed by analysis of variance (ANOVA) and second-order polynomial models were developed using multiple regression analysis both for pectin yield and GalA content. The models developed from the experimental design were predictive and good fit with the experimental data with high coefficient of determination (R2) value. Pectin yield and GalA content were more influenced by temperature. The highest extraction yield (10. 5%) and galacturonic acid content (65%) was obtained at pH of 2, temperature of 86℃ , time of 30 min, and power density of 0. 3 W/ml, while in the conventional extraction method with the same extraction conditions, extraction yield of 4. 5% and galactoronic acid content of 55% was obtained. According to results of this experiment, it can be concluded that main advantage of UAE is considerable shortening of extraction time with enhancement of pectin purity. Under optimal conditions, pectin with a degree of esterification 76% and intrinsic viscosity of 2. 6 dl/g was obtained. The highest emulsifying activity (87. 5%) was obtained at %1 concentration. By holding the emulsion at a temperature of 4° C and 23° C, the emulsion stability was significant (99%) at the concentration of %0. 25 over a period of 30 days. These results showed that tomato pomace could be used as a good source of low cost pectin.

Alginate is one of the unique polysaccharides present in brown algae which are widely used in textile, paper, and food, pharmaceutical, biomedical and cosmetic industries. There are many seaweed species in the southern coast of our country (Iran). However, very few studies have been done so far on the extraction of alginate from these indigenous resources. Therefore, in the present study, alginate was extracted and purified from a brown seaweed Sargassum ilicifolium. Then, yield, molecular weight, antioxidant activity (DPPH radical scavenging activity and reducing power (FRAP), and emulsifying properties (emulsification indices) of the isolated alginate were evaluated. Furthermore, FT-IR spectra were used to identify the functional groups of the extracted alginate. Alginate extraction yield was 20. 84± 1. 24% (based on seaweed dry weight). FT-IR results showed that the extracted polysaccharide was mainly sodium alginate. The molecular weight of the extracted alginate was 1865 kDa. The DPPH radical scavenging activity and the reducing power of the extracted alginate at 1 mg/ml were 18. 17± 2. 03% and 0. 155± 0. 004 (Abs), respectively. The extracted alginate was able to emulsify sunflower, corn, and canola oils. The highest and lowest emulsification indices (E24) were observed in sunflower and canola oils, respectively. Overall, the results of the present study showed that the alginate extracted from S. ilicifolium has medium antioxidant and high emulsifying properties.

Production of pasteurized liquid egg is a new technology in Iran. The main objective of egg pasteurization is manufacture of a safe product microbiologically, but lack of control of process causes remarkable irreparable damage to its properties such as emulsifying and it leads to financial loss, so protection of egg quality is a basic factor during pasteurization. Egg yolk with certain pasteurization conditions was produced and used as emulsifier for production of oil in water emulsion (30%) based on Box-Behnken design of experiments. Rheological properties were studied using Rheometer, particle size distribution by laser light scattering technique, and emulsion stability index according to turbidity measurement. Impact of temperature, NaCl and pressure on studied factors were evaluated by response surface methodology, and quadratic polynomial model was obtained for each response. To summarize, temperature increasing in lack of salt resulted in decrease of emulsifying characteristic of yolk due to denaturation of its proteins. NaCl retains the emulsifying of egg yolk as a result of protection against adverse effect of temperature during pasteurization. Following this further, homogenization pressure improves the emulsifying of egg yolk by uniformity of particle size and consistency. According to our findings, the results of available models are useful to estimate the impact of pasteurization conditions on responses in order to increase the quality of pasteurized liquid egg yolk.