محمود رضازاد

Study of genetic diversity using genetic markers is necessary to effective conservation of germplasm and to understand its genetic structure. Genetic variability in a species facilitate its adaptation to various environmental conditions. In the present study, genetic variability among 114 genotypes from 30 Pepper accessions were studied suing 11 ISSR primers and 14 morphological traits. Of 1653 locus pairs of ISSR markers, 7.04% showed significant level (P≤0.01) of linkage disequilibrium (LD). By analyzing genetic structure of population based on molecular data and using Bayesian model, 5 subpopulations (K=5) were identified. Association analysis was conducted using mixed linear model by considering kinship and genetic structure matrices as covariates in the model. Some molecular markers multiplied by 8 ISSR primers were identified to be significantly associate with 13 studied traits (P ≤ 0.05). Some markers were common among some studied traits that can be due to pleiotropy or linkage between loci controlling traits. Among studied ISSR primers, molecular markers produced by UBC834 primer showed the most association with the studied traits. Identified markers after validation can be useful in the development of pepper cultivars.

Nowadays, natural biopolymers such as proteins and polysaccharides in the preparation of biodegradable nanoparticles in food and pharmaceutical industries are of particular interest. The aim of this study was modeling and optimization of three component nanocomplex (protein, polysaccharide and small molecule emulsifier) production and study their stability using the BoxBehnken design. For each response, second order polynomial models were developed using multiple linear regression analysis. Analysis of variance confirmed that the models were highly significant (p

In addition to the numerous benefits of biopolymeric nanocomplex, it has drawbacks including difficulty in strict control of particle size and to prevent particle agglomeration. In this study, the influence of Tween 20 on the electrostatic interaction between sodium caseinate and gum Arabic was evaluated.
Initially, the organic phase (curcumin in ethanol) was introduced to aqueous phase (sodium caseinate, gum Arabic and Tween 20). Then by reducing the pH, the nanoparticles were formed. To evaluate the effects of the independent variables on the responses, the Box-Behnken design was used. The antioxidant activity of samples was evaluated by 1, 1diphenyl 2 picryl hydrazyl radical inhibition assay.
Tween 20 has a significant effect on particle size, and particle size distribution (p Due to the high encapsulation efficiency and antioxidant activity of curcumin nanocomplex and no need for high energy equipment such as homogenizer, this method is suggested as a simple, fast and low-energy technique.

Color is the fundamental qualitative characteristic of food products. Curcumin is a natural polyphenol found in the rizome of the turmeric. Curcumin, possesses multiple biological activities. However, its application is limited due to its poor water solubility and instability under adverse conditions. Encapsulation is a way to overcome these challenges. The aim of this study was to develop curcumin-loaded nanocapsules and evaluate the particle size and color parameters of the prepared product.
Initially, the organic phase (curcumin in ethanol) was introduced to aqueous phase (sodium caseinate, gum arabic and Tween 20). By reduction of the pH from 7 to 4.8, 5 and 5.2 nanoparticles were formed. Measurement of the particle size was carried outbyusing particle size analyzer. Color indices were determined using a Hunter lab. Box-Behnken design was used to explore the effects of 4 independent variables consisting of sodium caseinate (0.1-0.3 %w/w), gum arabic (0.5-1% w/w), Tween 20 (0.1, 0.2 %w/w) and pH (4.8, 5, 5.2) on the responses.
Theresults of the analysis showed that the effects of linear, quadratic and interaction of parameters on responses were significant. By increasing the biopolymers concentration, the particles size was increased from 120 nm to 984 nm. By increasing the concentration of sodium caseinate the brightness of samples was reduced.Samples containing Tween 20 had brightness and higher L*. In general, by reducing the particle size the color intensity of the samples was increased.
The best sample regarding the smallest particle size and curcumin color index was obtained at the concentration of 0.2 % sodium caseinate, 0.75 % gum arabic, 0.1 %Tween 20 and pH of 5. These nanodispersions might be useful as a hydrophobic nutrient delivery system as well as color factor for utilisation in functional food and beverage products.

Nowadays usage of molecularly imprinted polymers which act as artificial antibodies and separate target molecules from biological environments is a novel approach. Cholesterol is one of the major risk factors of cardiovascular diseases and its precise determination is crucial. In this research, a molecularly imprinted polymer by means of Fe3O4 nanoparticles coated with silica layer was fabricated and its functional characteristics were investigated.
Co-precipitation method was used for manufacturing of magnetic Fe3O4 nanoparticles coated by silica. Then cholesterol imprinted polymer were synthesized by grafting core-shell procedure. Finally obtained polymer was eluted by mixture of solvents to create specific adsorbent active sites for cholesterol. The polymer was incubated with cholesterol stock solution and binding activity was determined through high performance liquid chromatography. Structure and morphology of samples were evaluated by FT-IR spectroscopy and scanning electron microscopy.
Optimized ratio of polymer weight to cholesterol stock solution volume showed 94% separation from 100 mg/L stock solution. FT-IR spectrometry results revealed a fine coating of silica for magneticFe3O4cores.Silica band which was adsorbent of template molecule was intensified by sol-gel polymerization method. Polymer morphology was porous, spherical shaped and particle dimensions were observed less than 50 nanometers.
Application of Fe3O4 nanoparticles coated with silica in this method enables high separation of cholesterol which could be due to ease of extraction and grafted polymer nature. Morphology of adsorbent polymers indicated performance of nano surfaces in separation of this compound.

Apple pomace is a byproduct of apple processing plants which can be used as a good source for bioactive materials like phenolic compounds. In this research the 2 sub verities of Rhizopus oligosporus was used for production of Antioxidative bioactive compounds from Whey Proteine Concentrate (WPC) and apple pomace. Total Phenolic compounds، free radical scavenging ability by DPPH، Antioxidative Protection Factor (APF) and total count of molds were evaluated in 48 determined treatments. Effect of Incubation temperature in three levels 23،27،31°C، incubation time at 3،8،13 days، and Apple pomace/WPC ratio at three levels of 50:50، 70:30، 90:10 were studied. The polyphenol content، precent of DPPH inhibitation، APF and count of fungi of the extracts was found to be in the range of 6. 01-11. 12 mg GAE/g Dry Matter، 65. 8%-95. 2%، 1. 18-1. 55 and 2. 2*10^8-3. 13*10^10 of samples respectively، depending on the ratio of Apple/WPC، time of incubation، type of fungi and temperature. The highest efficiency obtained was related to Rhizopus oligosporus PTCC NO. 5287 and the results showed that the time of incubation had the most effect on measured parameters.

Biological nitrogen fixation is important for supplement of nitrogen needs of host plant. Growth chamber experiments were conducted to test the nitrogen fixing abilities of isolate of Rhizobium strains collected from 10 cities (Urmieh, Khoy, Makuee, Salmas, Mahabad, Miandoab, Tekab, Sardasht, Shahindege and Piranshar) of West Azerbaijan province in symbiotic relation with alfalfa, chickpea, clover and bean cultivars. Seedlings of test plants were inoculated with proprietary Rhizobium strains. Inoculated and control seedlings of each plants were planted in pots containing sterilized perlit. The experiment was conducted using completely randomized design with three replications. The pots were irrigated with free nitrogen Hoagland solution. Results showed that the highest number of nodule and the lowest nodule dry weight was for clover and bean, respectively.. Symbiotic of Rhizobium strain of Miandoab for alfalfa, Mahabad for clover and Urmieh for bean had the highest values for most of traits. Nitrogen fixation correlated with total dry matter, and it seems this trait may be used as an indirect criterion of nitrogen fixation. This findings imply the possibility of replacing biologically fixed nitrogen with chemical fertilizers.

A Box-Behnken design (statistical design) was applied to optimize the survival of Lactobacillus acidophilus and Bifidobacterium bifidum in bio-yogurt containing a new exudative Zedo gum. The effect of incubation temperature, storage time, Zedo gum concentration and probiotic inoculation load on probiotics survival, viscosity, acetaldehyde content and other quality indices of yogurt were explored. With respect to probiotics survival, probiotic inoculation load was found to be the most important factor followed by storage time. Zedo gum didn’t show significant effect on probiotics survival (α≥0.05). Viscosity and syneresis of yogurt samples were improved by addition of Zedo gum. Acetaldehyde content, the most potent odorant in yoghurt, was measured using GC-FID. Acetaldehyde content of the samples was not affected by probiotics and Zedo gum but increased by storage time. The optimum conditions of bio-yogurt production were: probiotic inoculation load, 12.24 g/100 kg of milk; incubation temperature, 41.6 °C; storage time; 28.8 days; and Zedo gum concentration, 0.2%. Under such conditions, the predicted Lactobacillus acidophilus, Bifidobacterium bifidum counts, viscosity and acetaldehyde content were 108, 109.6 cfu/g, 3655 cP and 28.2 ppm.