جستجوی مقالات مرتبط با کلیدواژه "protein" در نشریات گروه "فنی و مهندسی"

Seed aging is a process that can lead to a complete loss of seed viability. This process occurs when seeds are exposed to long-term storage or controlled deterioration treatments such as excessive dryness, lack of oxygen, and temperature fluctuations on Earth or in outer space. Proteomic changes can occur in the dry state of seeds. Extreme temperature fluctuations in outer space, especially on the moon and Mars, are one of the most important challenges for space scientists to transfer plant seeds and grow them in outer space outside the atmosphere. The present study studied the effects of simulated space temperature fluctuations on the quantitative and qualitative content of dry tomato seed proteins. The results showed 13 protein bands in the molecular weight range of 8.89 to 91.82 kilodaltons. A double or more significant decrease in the intensity of protein bands with high molecular weight was also observed in the treated group compared to the control. Finally, the two-dimensional electrophoresis technique followed by mass spectrometry is suggested for better resolution of tomato seed proteins and their better separation, as well as identification of unknown protein bands in future studies.

Silk is a natural fiber composed of proteins produced by some insects. Spiders produce protein macromolecules with different molecular structures for different applications. Spider web or other large protein structures are produced by the release of protein fibers from the spinning glands inside the spider's body, which act as a spinning instrument. Spider natural silk has received a lot of attention, due to its unique mechanical and physical properties, thermal resistance, biocompatibility, and biodegradability. These exceptional properties have led to the potential applications of spider silk fibers in production of bulletproof vest, artificial vessels, sensors, and etc. This interesting mechanical and physicochemical properties are due to the macromolecular structure of protein molecules as well as physical interactions between protein chains. derived from protein macromolecule’s structure, including the large protein sequences of the repeating units as well as physical interactions between protein chains and specific mechanisms such as tension, pH adjusting, and ion exchange in spinnerets of spider. Due to the remarkable difficulties in natural production of spider silk, other advanced techniques like inserting spider DNA in animals or bacteria is employed, but fibers produced by these methods do not have mechanical and physicochemical properties of natural spider silk lower molecular weight of the protein chains. Spider silk fibers have potential applications in pharmaceutical and military industries and this study can open a new window to the future of these fibers.

Since reducing or increasing proteins could be the signs of diseases in the body, they could be used as biomarkers for diagnosing some diseases. This study investigated small protein strings by computing the magnetic resonance spectrum of the nucleus. Amino acids are the building blocks of protein in the body, and the body does not produce the essential amino acids. They must reach the body through the food chain. Because essential amino acids are required for vital processes such as protein production and hormone synthesis, they are of great importance and are studied in this study. First, strings of two to six amino chains with the same monomers were modeled using Gauss View software, and their magnetic resonance spectrum was calculated using Gaussian09w software. These structures are modeled to investigate factors such as the type and length of the amino acid chain on the amplitude and location of the maximum peak in the magnetic resonance spectrum of the nucleus. The results show each amino acid has a unique own magnetic resonance spectrum and these amino acids in a polypeptide chain affect magnetic resonance spectrum. The ability of the nuclear magnetic resonance method to diagnose and identify a variety of diseases, its non-invasive nature, as well as the possibility of repeatability of experiments, in addition to reducing the cost of experiments, make this method as one of the novel and advanced diagnosis.

Evolution has been optimizing proteins for light reception and energy conversion for more than 3.5 billion years. The use of genetic engineering and bio-dyes has provided an array of new materials that have enhanced properties. Dye-sensitized solar cells based on bio-photosensitizers (bio-sensitized DSSCs) are promising bio-photoelectronic devices for electrical energy preparation. In this paper, a comprehensive study was presented on the mechanisms involved in the utilization of bio-dyes for an improved bio-sensitized DSSCs performance. Protein complexes, and chlorophyll a and carotenoids are among many bio-photosensitizers demonstrating high incident photon-to-current efficiency (IPCE). Like other sensitizers, the band- gap is an important factor in final performance of the optical component. Theoretical-average HOMO-to-LUMO band-gaps of 2.46, 5.22, 4.13, 1.13, 3.15, and 2.22 eV were calculated for anthocyanin, carotenoid, chlorophyll, cyanine, xanthene, and coumarin, respectively. It is more probable that low dye band-gaps result in enhanced HOMO-electron excitation and e-h pair generation. The highest conversion efficiency for bio-DSSCs based on PPB+Spx is about 4%. 

Albumin is a protein macromolecule that it has been attractive since the early 20th century and has several therapeutic applications. Albumin is an aboundant serum with good biocompatibility, hematopoiesis and biodegradability in blood. The existence of multiple functional groups makes it possible to carry significant amounts of therapeutic and diagnostic factors, as well as targeting factors. This protein, on the one hand, has therapeutic uses and, on the other hand, is used in various formulations to carry pharmaceutical and diagnostic agents. There are many benefits to albumin-based nanocomposites in facilitating their clinical applications in a variety fields, including drug release, imaging, teranostic, tissue engineering, and coatings.

Microalgae are promising sources of protein due to their high nutritional value, rapid growth rate and ability to survive in harsh conditions. In this study, first, different and indeterminate species of microalgae were cultured in flat plate photobioreactors and for the first time, the process of protein extraction from mixed microalgae biomass using various pretreatment methods such as autolysis, hydrolysis with acidic and alkaline methods, ultrasound and their composition was investigated. In acidic and alkaline pretreatment using solutions with different concentrations and at different times, the highest percentage of protein extraction (at 121 temperature and duration of 30 minutes) was 83% and 93%, respectively, which showed that the use of alkali was more efficient in protein extraction. Also, using autolysis and ultrasound methods, the highest extraction efficiencies were 60% and 39% of total protein, respectively. In this study, an autolysis with freezing method was used for the first time and based on the results, the efficiency of the autolysis process increased by 3 to 10%.

Because of the importance of biomolecule extraction and its genetic investigations in the medical and forensic field with all the limitations such as sensitivity, nature of work, high cost, the need for highly skilled technicians, automation and portability of the system in terms of detection with existing technologies, several need not fulfilled. There is a need to integrate sample preparation and detection methods. To overcome these limitations,
nowadays most studies have focused on improving detection technologies, and accordingly, advances in detection technologies microfluidics is one of the best systems with convincing feautures. Other advantages of this technology including the extraction of DNA and protein which is involved automation in a sample preparation, the ability to operate in small sample sizes as well as minimizing the consumption, cost, and processing time of solvents.

Today, due to the use of eggs as a complete food package, directly and indirectly, it is important to maintain quality. In this study, fresh eggs purchased and after placing the samples under UV rays with different levels of parameters, they were divided into two groups of impregnated and not impregnated sunflower oil. The samples were then stored for two days and then, the biochemical properties were determined for them including the percentage of fat and crude protein, pH and total ash. In the statistical analysis, the results for pure fat were the highest and the lowest was 48.3333 (20 lamps- 3 hours irradiation time) and 33.3333 (60 lamps- 1 hour irradiation time). In the study of the effects of the number of lamps and UV irradiation time on total ash, no significant changes were made at different levels of the parameters. There were also significant changes in the number of LED lamps and irradiation times in the raw protein review so that the highest level of protein in the parameters studied in this section was 40 lamps and 1 hour of irradiation and the lowest level The protein was about 20 lamps and 2 hours of ultraviolet radiation. In the pH check, the increase in the number of ultraviolet lamps and irradiation time reduced the amount of pH; As a result of the inverse relationship between the increase in the number of LED lamps and the irradiation time with the pH value. Also performing impregnated eggshell sunflower oil was a decrease in pH value.

The aim of this study was to evaluate the toxicity effect of Cadmium heavy metal on some serological parameters of Silver carp which have been in the vicinity of cadmium for a short term. In this study a total of 135 fish with mean weight of 50±10grand mean length of 13±1cm were placed in 9 aquariums of 90-liter capacity, in contact with 0.5 and 10 mg/L of CdCl2.Sampling of fishwas done randomly every 12 hours until 96 hours from caudal vein. The results showed that, the level of triglyceride in 24 and 48 hours decreased significantly, but showed no significant increase in 72 hours. The level of cholesterol increased significantly at 72 and 96 hours with increasing the concentration of cadmium (P<0/05). Glucose level increased significantly in 72 hours, but significantly decreased with increasing the concentration of cadmium in 72 and 96 hours (P<0/05). The level of total protein decreased significantly in 24 and 96 hours with increasing the concentration of cadmium, and in 72 hours increased significantly (P<0/05). The level of albumin increased significantly in 96 hours. Based on these results, biochemical parameters are useful for monitoring of cadmium acute toxicity in Silver Carp.

The aim of this study was to evaluate the toxicity effect of lead heavy metal on some serological parameters on Silver Carp in the vicinity with lead for a short term. In order to do this study a total of 135 fish with mean weight of 50±10 gand mean length of 13±1 cm were placed in adjacent to 0, 5 and 10 mg/l of Pb (NO3 )2 in 9 aquariums of 90 liter capacity.Sampling was done randomly each 12 hours for 96 hours from caudal vein of the fishes. The results showed that there was a significant difference in the amount of hemoglobin in 24 hours, between the control and treatments. The level of glucose was increased significantly by increasing the concentration of lead and passing of the time. The levels of triglyceride and albumin did not change significantly (P>0/05). The level of cholesterol increased significantly until 72 hours and after that decreased significantly. Amount of total protein increased significantly by increasing the concentration of lead and time. Based on the results, biochemical parameters are useful for monitoring of lead acute toxicity in Silver Carp.

The aim of this study was to assess protein, lipid, carbohydrate, fiber, ash, and moisture in two species of fishes, Aspius vorax and Carasobarbus luteus, in 2011. Fifteen samples of Carasobarbus luteus and 12 samples of Aspius vorax were collected from the Karkheh River. Mean levels of protein, lipid, ash, moisture in Carasobarbus luteus were 17.19±0.36, 3.23±0.15, 1.28±0.07 and %74.03±0.32, respectively. Similarly, the same chemical contents in Aspius vorax were 18.10±0.36, 2.60±0.20, 1.18±0.09 and %72.10±0.40, respectively. Level of moisture in muscle of two species of Aspius vorax and Carasobarbus luteus were significancantly different (P<0.05), but no significant difference was noticed for protein, ash and lipid (P>0.05). However, Protein in muscle tissue of Aspius vorax was more than Carasobarbus luteus, but lipid, moisture and ash in muscle tissue of Carasobarbus luteus was more than Aspius vorax. Therefore, the results showed that, in terms of animal protein, Aspius vorax is more appropriate compared to Carasobarbus luteus.

The aim of this study was to evaluate the toxicity effect of zinc heavy metal on some serological parameters on Silver carp in the vicinity with zinc in short term. In order to do this study a total of 135 fish with mean weight 50±10gr and mean length 13±1cm were located to adjacent to 0.5 and 10 mg/L of Zn (NO3)2 in 9 Aquarium with 90 liter of capacity.Sampling of fish was done randomly each 12 hours until 96 hours from caudal vein. The result showed that the level of cholesterol in 10 mg/L treatments in 96 hours were significant difference with 5 mg/ L and control treatments (p<0/05). The results showed that the minimum amount of cholesterol in 10 mg/L treatment in 96 hours was (10.83±0.2 mg/ dL) and the maximum amount was found in 5 ppm treatment in 48 hours was (102.7±22.7 mg/dL). Mean triglyceride fluctuated, so that the maximum amount of triglyceride was found in 10 mg/L treatment in 12 hours (93±14) mg/dL) and the minimum in 96 hours in 5 mg/L treatment was (24.4±2 mg dl). By increasing the concentration of zinc. albumin level were increased significantly. The minimum amount was found in control treatment which was (0.73±0.14 g/dL) and the maximum level in 5 m/g/L treatment at 96 hours was (9.03±0.6 g/dL). Total protein levels were decreased significantly (p<0.05). The minimum amount of total proteins in 5 mg/L treatment at 96 hours was (0/043±0/003) g/dL, and the maximum amount was at 12 hours in 10 mg/L treatment at (3/53±0/3)g/dL. Based on results, Hematological and biochemical parameters are useful for monitoring of Zinc acute toxicity in Silver carp.