Showing 18 results for Alishahi
Volume 4, Issue 2 (9-2015)
Abstract
The aim of this study, in the first step, was to recover the protein content in wastewater of fish meal factories using chitosan, chitosan nanoparticles and chitosan-aluminum sulphate composition. In the second step, the extracted protein was assessed for its essential amino acids profile. Also, the reduced amount of proteins in the waste water was evaluated by measuring different parameters such as turbidity, pH, COD. Finally, chitosan nanoparticles characteristics were investigated using atomic force microscopy. Results showed that turbidity, COD and soluble protein significantly decreased upon adding different concentrations of chitosan, nanoparticle of chitosan and chitosan-alum (p<0.05). The maximum protein recovery was related to chitosan-alum composition and chitosan nanoparticles with no significant difference between these two treatments. Evaluation of recovered protein in term of amino acids profiles showed that there were essential amino acids such as histidine, lysine, methionine and phenylalanine in protein of fish meal wastewater.
Volume 4, Issue 3 (12-2015)
Abstract
Protein hydrolysate (PH) from viscera of cultured Siberian sturgeon (Acipenser baerii) was produced. To optimize the production conditions, Response Surface Method (RSM) was employed to examine the effects of three different operating conditions, including time, pH, and enzymatic concentration (Alcalase) on the degree of hydrolysis.The mathematical model showed acceptable fitness of the experimental data as R2 equaled 0.97, which indicated that major part of the variability within the range of values could be explained by the model. The results showed that the highest degree of hydrolysis (58.21%) was related to the treatment which happened at the enzymatic concentration of 2%, 60 minutes time, and pH=8. Treatment under hydrolysis condition (i.e., E/S = 2%, Time = 45 min, and pH = 8.5) had the highest protein content (42.37g/l), which was used as an alternative to commercial peptone medium (Triptic soy broth) to assess the growth of Salmonella typhi bacteria from 0 to 48 hours. Although there was an upward trend in growth rate of S. typhi both in control and No. 15 (Alcalase) treatments, the log growth of control treatment was found to be better than that of Alcalase treatment. However, there existed no significant difference between the two treatments.
Volume 8, Issue 4 (Fall 2019)
Abstract
Aims: The aim of this study was to investigate the effect of cooking (frying and microwave), chitosan additive and freezer storage on the fish fillet in terms of sensory and color evaluation and weight changes.
Methodes: Cultivated fish fillets, frozen at -18 ° C for 4 months. They were then transferred to the Fisheries Processing Laboratory of the Faculty of Fisheries, Gorgan University of Agricultural Sciences and Natural Resources, in the shortest possible time (day 0, day 2 and month 4). The fillets were frozen and cooked in a pan and microwave. The experiment was designed in 4 treatments: T1 (fried sample without chitosan), T2 (fried sample containing 1% acid-soluble chitosan), T3 (microwave cooked sample without chitosan), T4 (Microwave cooked sample containing 1% acid-soluble chitosan). Fillet weights were measured before and after cooking. Sensory evaluation and colorimetric evaluation of fillets were also performed after cooking.
Findings: The use of 1% acid soluble chitosan had no significant effect on sensory parameters and colorimetric factors (p> 0.05). Weight changes in fried fillets increased over time but decreased in microwave-cooked fillets over time.
Conclusion: The use of natural additives such as acid soluble chitosan 1% had no significant effect on the sensory indeces compared to the control group. In terms of colorimetric factors, chitosan had a positive effect on yellowness index. In terms of cooking and having a safe product, it is very important that the weight factor of the microwave cooked fillets is more favorable than the fried fillets.
S. Mashjoor , M. Alishahi , Z. Tulaby Dezfuly ,
Volume 9, Issue 3 (Summer 2018)
Abstract
Aims: The bio-toxicity of silver nanoparticles (AgNPs) in the aquatic ecosystem and the detection of lethal concentrations of this material are of importance. The aim of this study was in vivo comparative toxicity of silver nanoparticles and bio-productivity in zebrafish (Danio rerio) in embryo and adult stages.
Materials and Methods: The present experimental study was carried out on 30 fertilized eggs and 30 adult zebrafish and the effects of chemical and bio-productivity of AgNPs were evaluated by brown seaweed (Sargassum boveanum) in evolutionary stages of the embryo and adult zebrafish with a control group and in incremental concentrations. The mortality rate was recorded at 24, 48, 72, and 96 hours after exposure and the data were analyzed by EPA Probit Analysis 1.5 and SPSS 19 softwares, using one-way analysis of variance and Duncan's multiple range test.
Findings: The toxicity of both types of AgNPs in both evolutionary stages was increased with increasing concentrations and time (p<0.05). After 96 hours, the lethal concentration 50 (LC50) in adult fish was 0.788mg/l for chemical AgNPs and 0.409mg/l for bio-produced AgNPs. Mortality rate at the highest concentration (3mg/l) of AgNPs at 72 and 96 hours in all groups was 100%.
Conclusion: Comparison of the toxicity result showed that the biosynthesis form of AgNPs is more toxic potential than chemical form of AgNPs. It seems the sensitivity of embryo stage to both of silver nanoparticles more than to mature stage.
S. Mashjoor , M. Yousefzadi , H. Zolgharnain , E. Kamrani , M. Alishahi ,
Volume 9, Issue 4 (Fall 2018)
Abstract
Aims: In nanoecotoxicology science, fish erythrocyte micronucleus assay for the monitoring genotoxic potential of nanoparticles is a powerful biomarker. This study was conducted with the aim of investigating genotoxicity of magnetic iron oxide (Fe3O4) nanoparticles in red blood cells of common carp (Cyprinus carpio) using micronucleus assay under acute and chronic treatment. Materials and Methods: In the current experimental study, the genotoxit toxicology of Fe3O4 nanoparticles was performed during an acute (96 hours; 5 concentrations including 0, 10, 100, 500, and 1000 mg/l) and chronic (14 days; 3 concentrations including 0, 100, and 500 mg/l) of Fe3O4 nanoparticles in three replications. The data were analyzed by IBM SPSS 19, using two-way ANOVA, and Duncan's new multiple range test.
Findings: Acute exposure to Fe3O4 nanoparticles had no acute toxicity effect juvenile carp (C. carpio). By increasing the concentration of nanoparticles in a 96-hour interval, the frequency of micronucleus (‰) and other abnormal forms around the red blood cell nucleus of juvenile carps showed a significant increase compared to the control group (p<0.05). In the chronic treatment at concentrations of 100 and 500 mg/l of Fe3O4 nanoparticles, the rate of increase in the frequency of micronucleus was similar to the acute functional test of concentration.
Conclusion: Although Fe3O4 nanoparticles do not have acute toxicity effects in common carp and are non-toxic, they tend to induce genotoxic effects by increasing the frequency of micronucleus and other abnormalities of the red blood cell core during a concentration-dependent process. So, it seems that the release of FeO4NPs into the environment, it is probable adverse effects on aquatic ecosystems.
Volume 10, Issue 1 (1-2021)
Abstract
The purpose of this study is to evaluate the purchase amount of shrimp in the market and the relationship between consumption amount and some of demographic characteristics. The statistical population of this study is the whole country that 10 cities including Mashhad, Tehran, Tabriz, Birjand, Kermanshah, Gorgan, Yazd, Bandar Abbas, Ilam and Shiraz were randomly selected and a total 1000 questionnaires were completed by citizens proportionate to the household population of the studied cities. In order to evaluate the number of shrimp purchases per year as well as the amount of each purchase, from the output of SPSS software and to investigate the existence of a significant relationship between consumption amount and demographic characteristics, correlation tests were used. According to the results the number of times shrimp were bought by the household varied from one to twelve times a year (average 1.71±1.11). 44.2% of households of the consumption society bought shrimp once a year and 28.6% of them bought shrimp twice a year. It was further found that the amount of shrimp purchased by household varies from 0.5 to 2 kg per purchase (average 0.92±0.26 kg). while 76.3% of households of the consumption society purchase one kilogram of shrimp in per purchase. According to the findings, consumption amount had no significant relationship with the age, job and field of study variables (p>0.05). But the relationship between this index with the education level and number of household members variables was significant (p<0.05).
Volume 12, Issue 2 (4-2023)
Abstract
Chitosan (Cs) was extracted from shrimp shell and its derivative forms including N-alkyl (AlkCs) and nanoparticles (CsNPs) were prepared. First, the properties of nanoparticles were determined by dynamic light scattering (DLS) and the morphology of nanoparticles and N-alkylated by scanning electron microscopy (SEM). Then their antibacterial activity was evaluated by the test of minimum inhibitory (MIC) and lethal (MBC) concentration, diffusion on agar by disk, permeability of cell membrane by measurement of cytoplasmic beta-galactosidase release (ONPG). The type of apoptosis cell death was also examined by DAPI staining and changes in cell surface integrity by atomic force microscopy (AFM). The results showed that the nanoparticles are spherical with an average hydrodynamic diameter of 240 nm. N-alkyl had a rough surface structure compared to native chitosan. At the least of MIC (78 μg/ml) and MBC (100 μg/ml) points were observed for CsNPs (P < 0.05). Nanoparticles and N-alkyl of chitosan showed the highest diameter of growth inhibition zone at 1250 concentration compared to other disks (p <0.05). Outer membrane permeability of derivative forms of chitosan showed significant differences with native chitosan and cells of control. DAPI staining test showed higher cell death of chitosan-derived forms. DAPI staining test showed higher cell death of derivative of chitosan. The images obtained from AFM showed a change in the membrane integrity of the treated cells compared to spherical and clustered of control cells. Thus, the antibacterial properties of native chitosan improved by physical and chemical modification.
Volume 13, Issue 1 (1-2024)
Abstract
The present study was aimed to investigate the physicomechanical properties of biodegradable ternary films based on chitosan (CH) and starch (ST) at different ratios (100ST/0CH, 75ST/25CH, 50ST/50CH, 25ST/75CH and 0ST/100CH) via a simple casting method.The results showed that adding different ratios of chitosan (25-75%) to the control film (100ST:0CH)significantly reduced the moisture content, and elongation at break (EAB) and water vapor permeability (WVP) of the films, as the 75ST:25CH ratio has the lowest values; also, the solubility, tensile strength, contact angle and whiteness index of the films showed a significant increase compared to the control (p <0.05). FT-IR spectra of different films showed interactions through hydrogen bonding between the hydroxyl moieties of ST and amino moieties of CH in the blends, which enhanced the compatibility between the two polymers. On the other hand, the indicators related to the DSC test indicated that the thermal stability of composite films reduced after the addition of ST. SEM microstructural observations clearly demonstrated a re-organization of the surface of the two-phase films due to the presence of ST.The obtained results suggested the effectiveness of blending approach in improving the compatibility of polymers and overall functionality of films.
Volume 13, Issue 2 (6-2024)
Abstract
Aims: The purpose of this research was to evaluate the consumer’s behavior of farmed carp in the north of Iran (Golestan, Mazandaran and Gilan province). Method: After defining the assumptions and designing the analytical-conceptual model based on the theory of planned behavior, a suitable questionnaire was developed and completed by the statistical community. In order to evaluate the intensity of the relationship between the research variables and the model elements, as well as to check the acceptance or non-acceptance of the assumptions, the structural equation modeling method (SEM) was used. Findings: Per capita fish consumption of farmed carp consumers is 5.3 kg. Of this amount, 400 grams are canned, 600 grams are consumed in restaurants and outside the home, and 2.5 kg are consumed at home. Per capita consumption of their farmed carp is 1.4 kg, so half of their consumption is from other fish.In this research, all hypotheses were confirmed, In this way, the effect of perceived usefulness, perceived risk and quality on attitude, the effect of normative beliefs, moral obligation and household income on subjective norms, the effect of control power, control belief, experimental records, advertising and education on the perceived behavior control, the effect of attitude, subjective norms and perceived behavior control on the decision to buy farmed carp and the effect of the decision to buy and perceived behavior control on the final behavior were reported to be significant (p<0.05). The values of the effect coefficients showed that the most effective variable on the attitude, subjective norms and perceived behavior control, is quality (with an effect coefficient of 0.46), income (with an effect coefficient of 0.44) and experience records (with an effect coefficient of 0.37), respectively. Also, among the three main elements of the model, the attitude had the greatest effect on the decision to buy and consume farmed carp (with an effect coefficient of 0.48).
Volume 14, Issue 7 (10-2014)
Abstract
In this paper, control and guidance system of a spinning flight vehicle with a single plane of dithering canard control fins are investigated. Decreasing the number of actuators, lowering the vehicle weight, and reducing the final cost are outcomes of applying two canard controls; however, the control system will become complicated due to guidance system interaction. Producing asymmetric force and torque in yaw direction is the result of this interaction. Dithering canard is proposed for proper control of this spinning vehicle. Dithering canard adjusts its deflection with respect to the roll attitude of the flight vehicle. In this paper, a method is proposed for control and guidance of this spinning vehicle with dithering canard. This method is investigated in a six DOF flight simulation in presence of IR seeker, autopilot, gyro, actuators. Appropriate simulation results in various flight situations verify the proper performance of this new control method.
Volume 15, Issue 13 (Special Issue 2016)
Abstract
Volume 15, Issue 13 (Special Issue 2016)
Abstract
Volume 16, Issue 88 (6-2019)
Abstract
In this study, gelatin from common carp scales (Cyprinus carpio) was produced using alkaline, acidic and thermal methods. Then, the physical factors, barrier properties and its appearance characteristics were optimized by changing effective factors in the initial gelatin extraction process. In order to optimize the film, the response surface methodology included a central composite design for extraction process, a series of effective factors in extraction including sodium hydroxide concentration, alkaline pre-treatment, hydrochloric acid concentration and extraction temperature as independent variables were investigated. The dependent variables including tensile properties, water solubility and water vapor permeability were investigated. The results of screening based on mechanical strength and solubility resulted in the selection of 4 factors of 9 factors. In the screening stage, four variables including two factor of the pH of extraction and the duration of the alkaline treatment that had the greatest effect on the tensile strength, and two factor including concentrations of acid treatments and the extraction temperature that had the most effect on the solubility of the films were selected for the the main experiments with gelatin extraction. Other variables that did not have a significant impact on the mechanical properties and film solubility were in their most common form. The main experiments of gelatin extraction included 30 treatments. Solubility showed significant changes (p <0.05). The lowest solubility was 25.08% for treatment No. 9 with alkaline treatment for 195 minutes, acid treatment with 0.3 molar concentration and extraction at 63 ° C. The lowest permeability was for treatment No. 15 with alkaline treatment for 140 minutes, acidic treatment with a concentration of 0.18 molar and extraction at 76 ° C (p <0.05). Finally, it was determined that by changing some of the extraction factors, the properties of gelatin film obtained from common carp scales could be optimized.
Volume 16, Issue 90 (August 2019)
Abstract
Despite the high nutritional value of shrimp, its per capita consumption in the country is low. Therefore, it is necessary to investigate the reasons for this shortage and to propose ways to increase per capita consumption in order to maintain the health of the population. To this purpose, the behavior of shrimp consumers must first be evaluated. This study was conducted to evaluate the behavior of shrimp consumers in the country by using the general framework of the theory of planned behavior. The statistical population of the study was the whole country which selected 10 cities (Mashhad, Tehran, Gorgan, Bandar Abbas, Yazd, Shiraz, Kermanshah, Ilam, Birjand and Tabriz) by randomized sampling and completed 1000 questionnaires by citizens. Statistical analysis were performed using the Structural Equation Model and Liserl software. The results showed that attitude, subjective norm and perceived behavior control had a positive and significant effect on the intention to shrimp consumption. In addition, the perceived behavior control was also effective on increasing of shrimp consumption. It was found that only two assumptions about the significant effect of convenience of cooking on the attitude and the significant effect of income on the subjective norm were rejected and other assumptions (significant effect of quality, packaging and type of supply and processing on attitude, significant effect of price and positive and negative beliefs on subjective norm, significant effect of consumption time, availability and experimental records on perceived behavior control and significant effect of intention to consumption on increasing of shrimp consumption) were confirmed.
Volume 16, Issue 91 (September 2019)
Abstract
Celiac disease is an autoimmune disorder in which the patient is permanently exposed to gluten intolerance during their life. The only effective method for celiac disease is strict adherence to a gluten-free diet. So, attention to the high quality food production without gluten is important. The aim of this study is to produce gluten-free bread toast using Nigella sativa Linnconcentrate as an alternative to gluten and potato fiber. The Response Surface Method was used with two variables of potato fiber (2 to 6 %) and Nigella sativa Linnconcentrate (5 to 15 %). With increasing potato fiber and Nigella sativa Linnconcentrate, bread density increased significantly (p˂0.05). Potato fiber resulted in a significant decrease in porosity, but Nigella sativa Linnconcentrate was ineffective (0.01%). Potato fiber and Nigella sativa Linnconcentrate showed a linear effect alone at the level of 0.05. Moisture content decreased with increasing fiber and Nigella sativa Linnconcentrate, but the effect of protein concentrate was not significant (p˃0.05). In addition, moisture content of bread decreased during storage. Potato fiber and protein concentrate had a significant effect on the hardness of bread texture and the texture increased during the four days storage period. The non-fit index for all models was not significant (0.05%). The optimization of bread formulation showed that the toast containing 7.5% of Nigella sativa Linnconcentrate and 2.5% potato fiber had the best quality and is recommended for production.
Volume 16, Issue 93 (November 2019)
Abstract
In order to increase the per capita consumption of shrimp in Tehran and its proper placement in the household food basket, it is necessary to study the factors affecting the attitude of citizens towards shrimp consumption as well as the factors affecting on decision to purchase. The purpose of this applied-research study also is to investigate and evaluate these factors. For this purpose, by studying internal and external sources, a number of factors affecting consumers' attitudes and their decision to purchase were identified and then tested in the form of assumptions in the target population. The statistical population of the study is the whole city of Tehran which randomly were selected 12 municipal districts for field study with sample size of 500 people. To collect data, a questionnaire was designed according to the assumptions and completed by the consumption society. In order to test the assumptions and investigate the severity and direction of the relationship between their items, a conceptual model was designed and evaluated by structural equation modeling (Lisrel software). In testing hypothetical factors affecting citizens' attitudes were found quality, type of supply and processing, packaging and different beliefs have positive and significant effects on people's attitudes. But the convenience of cooking of shrimp as well as the time and place of consumption had no significant effect on the attitude of citizens. In the following, the results showed that experimental records of consumption, income and price of shrimp are effective on the intention to purchase but the access factor does not have a significant effect on the intention to buy shrimp. Values of effect coefficients showed that among the effective factors on attitude of citizens and the decision to buy, quality and experimental records of consumption are the most effective factors, respectively.
Volume 17, Issue 12 (2-2018)
Abstract
The intermetallic compound of gamma titanium aluminide is a kind of recently developed material which has outstanding potential for utilization in high temperature structural applications due to higher ratios of strength to density and also elasticity modulus to density. In this study with considering two dielectric fluids of kerosene and de-ionized water, the effects of the most important input parameters of electrical discharge machining including pulse current and pulse on time on the output characteristics of material removal rate, tool wear ratio, some surface integrity criteria such as surface roughness and cracks, are investigated. The results indicate that, rough machining of titanium aluminide in contrary to finishing of this material, is performed efficiently. As the result of more thermal conductivity coefficient of water comparing with kerosene, the energy dissipation or loss and also plasma channel radius expansion in water is noticeably more than kerosene. This issue leads to more concentration and higher rates of thermal energy on the machined surface in the case of kerosene. Consequently, the density of surface cracks, surface roughness and intensity of surface topography alterations for the machined surface in kerosene is more than the samples which are machined in de-ionized water, but in contrary, the material removal rate with kerosene is much more than MRR in de-ionized water and also the tool wear ratio during machining process by means of kerosene is significantly less than the de-ionized water.
Volume 20, Issue 7 (Supplementury Issue 2018)
Abstract
Starch and Soy Protein Isolate (SPI) have numerous applications in food products mostly as gelling and texturizing agents. The main purpose of this research was to investigate the pasting and gelling properties of the mixtures of starch and various levels of SPI (0, 5, 10, 15, 20 and 25%). To determine the effects of starch sources on the results, wheat and corn starches were tested in this study. It was found that with increasing the quantity of SPI, the viscosities obtained from Rapid Visco Analyser (RVA) including final, holding, and setback decreased while pasting temperature remained unchanged. Increasing the SPI concentrations enhanced the peak viscosity of the wheat starch-SPI samples, while it had opposite effects on corn starch-SPI samples. The colour of both starch-SPI gels became darker and more yellowish with increasing the SPI concentration. Although gel hardness increased during storage for 1 and 3 days at 4˚C, the addition of SPI reduced the hardness of the gels. The residual modulus of the Maxwell model from stress relaxation data showed that gels became softer and less elastic with increasing the SPI concentration. The corn starch-SPI gels exhibited darker color, higher firmness, cohesiveness, springiness, gumminess and chewiness compared to the wheat starch-SPI gels. The results may be useful to obtain the desired quality in food products containing starch and SPI.