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21.
Mana Mashkour Yahya Maghsoudlou Mahdi Kashaninejad Mehran Aalami 《Potato Research》2018,61(4):375-389
In this study, the effect of a vacuum impregnation (VI) process with pulsed electric field (PEF) pretreatment on fortification of whole potato with ferric pyrophosphate was investigated. The VI process and PEF pretreatment were optimized with respect to physicochemical attributes of PEF-VI-processed samples using response surface methodology (RSM). The results indicated that the iron content of VI-processed and PEF-VI-processed potatoes was increased about 126 and 457%, respectively, compared to unprocessed potatoes. A more intensive PEF pretreatment led to a higher cell disintegration, decrease in colour and textural parameters and also increase in components leakage from treated potato. Our study suggests that whole 180-g potatoes should be pretreated at 394 V/cm with 36 pulses and then treated at 3.5 kPa for 37 min in vacuum stage and 39 min restoration time in atmospheric stage to achieve the highest iron fortification and the lowest physicochemical changes during PEF-VI processing. 相似文献
22.
Majid Salehi Ahmad Vaez Mahdi Naseri-Nosar Saeed Farzamfar Arman Ai Jafar Ai Shima Tavakol Mehrdad Khakbiz Somayeh Ebrahimi-Barough 《Fibers and Polymers》2018,19(1):125-134
In the present study, naringin, a flavonoid isolated from the grape and citrus fruit species, was incorporated with poly(ε-caprolactone)/gelatin composite mats in order to develop a potential wound dressing. The composite mats were prepared by electrospinning of poly(ε-caprolactone)/gelatin (1:1 (w/w)) solution incorporated with 1.50 %, 3 % and 6 % (w/w) of naringin. The electrospun mats were evaluated regarding their morphology, contact angle, water-uptake capacity, water vapor transmission rate, tensile properties, drug release, cellular response and in vivo wound healing activity. The study showed that after 2 weeks, the full-thickness excisional wounds of Wistar rats treated with the naringin-loaded dressings achieved a wound closure of higher than 94 % and the dressing containing 6 % (w/w) naringin had almost 100 % wound closure. The sterile gauze, as the control group, showed nearly 86 % of wound closure after this period of time. Our results provided evidence that supports the possible applicability of naringin-loaded wound dressing for successful wound treatment. 相似文献
23.
Lactococcosis, a significant emerging disease of fish caused by Lactococcus garvieae, has become one of the devastating problems due to its serious economic damage in aquaculture. The aim of this study was to isolate and characterize a lytic phage infecting L. garvieae as a potential bioagent for the treatment of lactococcosis. In this regard, one strain of L. garvieae was isolated from diseased rainbow trout, and then, following biochemical and molecular identifications, its specific phage, WWP-1, which was able to destroy L. garvieae cells through the lytic cycle, was isolated from a municipal wastewater sample. Transmission electron microscope revealed that the isolated phage possesses an icosahedral head and a non-contractile short tail, resembled to members of the family Podoviridae. Moreover, phage WWP-1 represented optimal antibacterial activity at temperatures ranging from 15 to 30 °C, suggesting that it could be very effective at rainbow trout rearing temperature. Restriction profile analysis revealed that NdeI can digest WWP-1 genome while EcoRI, EcoRV, and BamHI were incapable of cutting its DNA. According to the in vivo experiment result, WWP-1 could decrease mortality rate of infected rainbow trout in aquaculture. The results suggest that this naturally occurring bacteriophage could be considered as a promising agent to control the disease caused by L. garvieae strains in rainbow trout rearing. 相似文献
24.
Parastoo Pourashouri Bahareh Shabanpour Seyed Hadi Razavi Seid Mahdi Jafari Ali Shabani Santiago P. Aubourg 《Journal Of Aquatic Food Product Technology》2013,22(6):567-578
Multilayer microencapsulation of fish oil was evaluated by using fish gelatin (treated with or without microbial transglutaminase [MTGase]), chitosan, and maltodextrin for its ability to control lipid oxidation. This study showed that a mixture containing gelatin and maltodextrin obtained the highest percentage of core release. The oxidative stability of the formulated mixtures and the bulk oils was investigated during a period of 60 days. The peroxide value (PV) was assessed as a parameter for primary oxidation products, and p-anisidine (p-AV) and thiobarbituric acid reactive sub-stances (TBARS) was used to analyze secondary oxidation compounds. Observation of oxidation products showed that combinations of gelatin and maltodextrin made by adding MTGase and a mixture of gelatin and chitosan were able to increase the oxidative stability, and increases in PV and p-AV and TBARS were found for all oils. 相似文献
25.
Cotton fabrics were dyed with three commercial vat dyes in order to provide camouflage in Vis-NIR regions and imitate reflectance profile of greenish leaves. To investigate the effect of nano particles on camouflage properties of dyed fabric, nano particles of TiO2 were applied on dyed fabrics using pad-dry-cure method. The nano TiO2 padded dyed fabrics were investigated using scanning electron microscopy (SEM). Reflectance curves of coated dyed samples with different concentrations of nano TiO2 were measured. Results showed that in both of the standard shades, nano TiO2 increases the reflectance value in NIR region and with increasing the concentration of nano TiO2, the reflectance curves of samples tend to show the maximum reflection of greenish leaves (deciduous leaves) in NIR region. Chromatic values (CIE1976 L*, a*, and b*) and color difference (according to CIECMC color difference ΔE*cmc (2:1)) of each of the coated samples were measured using the reflection spectrophotometer. By considering the influence of white color of nano TiO2 on green shade of dyed cotton fabrics and increasing the color difference (between coated samples and the standard shades of the 1948 U.S army pattern) in visible range, optimum concentrations of nano TiO2 for development of camouflage properties on cotton fabrics in both NIR and visible region were determined. These values for NATO and forest green shades were 0.75 % and 0.5 %, respectively. Fastness results showed that both of the samples have acceptable color fastness. The effect of washing and exposure to light on camouflage properties of coated dyed fabrics in visible (in term of chromatic values) and NIR region (in term of spectral reflectance) was investigated when those were coated in optimum concentrations of nano TiO2. The results showed that the effect of after treatments (washing and exposure to light) on surface color spectral characteristics and camouflage properties was inconsiderable. 相似文献
26.
The aim of this work was to evaluate the effective parameters for prediction of the electrospun gelatin nanofibers diameter using artificial neural network (ANN) technique. The various sets of electrospinning process including temperature, applied voltage and polymer and solvent concentrations were designed to produce pure gelatin nanofibers. The obtained results by analyzing Scanning Electron Microscopy (SEM) images indicated that the produced nanofibers diameter was in the range of 85 to 750 nm. Due to the volume of the data, k fold cross-validation method was used for data setting. Data were divided into the five categories and trained and tested using ANN technique. The results indicated that the network including 4 input variables, 3 hidden layers with 10, 18 and 9 nodes in each layers, respectively, and one output layer had the best performance in the testing sets. The mean squared error (MSE) and linear regression (R) between observed and predicted nanofibers diameter were 0.1531 and 0.9424, respectively. The obtained results demonstrated that the selected neural network model had acceptable performance for evaluating involved parameters and prediction of nanofibers diameter. 相似文献
27.
Issa Mohammadpourfard Mir Mohammad Shamloo Anbardan Navid Eshghi Mahdi Jahanbakhsh Arash Akbarzadeh Saeed Ghorbani Bejandi 《Journal Of Aquatic Food Product Technology》2017,26(6):756-768
Today, due to the rapid spoilage of fish, the use of natural preservatives is a priority over those of synthetic varieties. Also, the natural antimicrobial effects of essential oils can help to increase shelf life. There are very few studies concerning the use of essential oils in this regard. In the present study, the antibacterial effect of chitosan coated with Heracleum persicum oil was investigated on the quality of rainbow trout. The control and the coated fish samples were analyzed periodically by generalized estimating equation (GEE) for total viable count (TVC), psychrophilic bacteria, total volatile base nitrogen (TVB-N), polyunsaturated fatty acids (PUFA), texture, taste, odor, and overall acceptance parameters. The results showed that by increasing the amount of chitosan, TVC, psychrophilic bacteria, and TVB-N decreased while PUFA, texture, taste, odor, and overall acceptance parameters increased. 相似文献
28.
Comparative effects of Shirazi thyme and vitamin E on some growth and plasma biochemical changes in common carp (Cyprinus carpio) during cadmium exposure 下载免费PDF全文
Mohammad Mohiseni Maryam Sepidnameh Dara Bagheri Mahdi Banaee Behzad Nematdust Haghi 《Aquaculture Research》2017,48(9):4811-4821
Phytobiotics include a large number of active components which potentially have a growth‐promoting effects and antioxidant properties. This study was conducted to investigate the protective effects of Shirazi thyme and vitamin E on growth and plasma biochemical parameters of common carp exposed to cadmium. Fish (34 ± 3 g) were divided into four groups and fed four distinct diets including commercial diet without any additive (for control and metal only group) and supplemented with either 1% ground Shirazi thyme or 100 mg kg?1 vitamin E for 45 days. At the end of the feeding trial, all treatments except control group were exposed to sub‐lethal concentration of waterborne cadmium for 15 days and sampling was done on days 0, 7 and 15 after the metal exposure. According to the results, dietary inclusion of thyme prevented the harmful effects of cadmium and also improved fish growth and nutritional indices including weight gain, feed conversion ratio, specific growth rate and condition factor. Results also revealed that Shirazi thyme was more effective than vitamin E. Similarly, no changes in the hepatosomatic, viscerosomatic and bile somatic indices were observed. Plasma enzymes (AST, ALT, ALP and LDH) and metabolites were not altered due to thyme supplementation compared to the control. In conclusion, dietary supplementation of 1% ground Shiraz thyme improved the growth and health status of fish and showed better hepatorenoprotective properties than vitamin E during waterborne cadmium exposure in common carp juveniles. It might be conceivable to consider Shirazi thyme as a potential phytobiotic for incorporation in fish diet. 相似文献
29.
Mahdi Naderi Saeed Keyvanshokooh Amir Parviz Salati Alireza Ghaedi 《Fish physiology and biochemistry》2017,43(5):1373-1385
The main aim of the present study was to assess the effects of chronic high stocking density on liver proteome of rainbow trout. Rainbow trout juveniles (42.6 ± 2.3 g average body weight) were randomly distributed into six tanks at two stocking densities (low stocking density (LD) = 20 kg m?3 and high stocking density (HD) = 80 kg m?3). Both treatments were performed in triplicate tanks for a period of 60 days. High stocking density caused a reduction in the growth performance compared with LD fish. Lysozyme activity increased with stocking density, while serum complement activity presented the opposite pattern. Serum cortisol and total protein levels did not show significant differences (P > 0.05) between experimental groups. The fish reared at high stocking density showed significantly lower osmolality and globulin values but higher albumin level. The HD group had significantly higher activities of catalase, glutathione peroxidase and superoxide dismutase, and malondialdehyde content in the liver when compared to the LD group. Comparative proteomics was used to determine the proteomic responses in livers of rainbow trout reared at high stocking density for 60 days. Out of nine protein spots showing altered abundance (>1.5-folds, P < 0.05), eight spots were successfully identified. Two proteins including apolipoprotein A-I-2 precursor and mitochondrial stress-70 protein were found to increase in HD group. The spots found to decrease in the HD group were identified as follows: 2-peptidylprolyl isomerase A, two isoforms of glyceraldehydes-3-phosphate dehydrogenase, an unnamed protein product similar to fructose-bisphosphate aldolase, 78 kDa glucose-regulated protein, and serum albumin 1 protein. 相似文献
30.
Mahdi Ghorbanalizadgan Bita Bakhshi Anoshirvan Kazemnejad Lili Shahin Najar-Peerayeh Bahram Nikmanesh 《Iranian Biomedical Journal》2014,18(3):158-164
Background: The aim of this study was to determine the prevalence of virulence-associated genes and enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) analysis of Campylobacter spp. isolated from children with diarrhea in Iran. Methods: A total of 200 stool specimens were obtained from children under 5 years during July 2012 to July 2013. Detection of C. jejuni and C. coli was performed by standard biochemical and molecular methods. The presence of virulence-associated genes and genetic diversity of isolates was examined using PCR and ERIC-PCR analyses. Results: A total of 12 (6%) Campylobacter spp. were isolated from patients including 10 (4.5%) C. jejuni and 2 (1.5%) C.coli. The flaA, cadF and ciaB genes were present in 100% of isolates, while no plasmid of virB11 gene was present in their genome. The prevalence of invasion-associated marker was 100% among C. coli and was not detected in C. jejuni isolates. The distribution of both pldA and the genes associated with cytolethal distending toxin (CDT) was 58.3% in C. jejuni isolates. Seven distinct ERIC-PCR profiles were distinguished in three clusters using ERIC-PCR analysis. Genotyping analysis showed a relative correlation with geographic location of patients and virulence gene content of isolates. Conclusion: To our knowledge, this is the first molecular survey of Campylobacter spp. in Iran concerning genotyping and virulence gene content of both C. jejuni and C. coli. ERIC-PCR revealed appropriate discriminatory power for clustering C. jejuni isolates with identical virulence gene content. However, more studies are needed to clearly understand the pathogenesis properties of specific genotypes. Key Words: Campylobacter jejuni, Campylobacter coli, Ddiarrhea, Virulence factors 相似文献