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Purification and immobilization of Lactoperoxidase extracted from camel milk using sodium alginate
2016
Zibaei, Saeed | Barazandeh, Reza | Eshaghi, Zarrina | Jafari, Seyed Mehdi
BACKGROUND: Lactoperoxidase is an enzyme of the oxidoreductase family. Lactoperoxidase is an important antimicrobial agent. Applications of lactoperoxidase are being found as a preservative in food and cosmetics. Immobilized LPO provides several significant benefits such as: easily separated from the reaction products, reducing production costs by efficient recycling and control of the process. Objectives: Purification and immobilization of lactoperoxidase extracted from camel milk using sodium alginate polymer. Methods: The lactoperoxidase was purified from camel milk by using sephadex G-100 gel filtration CM and sephadex C-50 ion-exchange chromatography. Encapsulation was carried out by using LPO, sodium alginate, glycerol and Tween 80. Afterward, the microcapsules were stablized by calcium ion (1%). Efficiency of encapsulation was calculated. The particle size and distribution were measured with particle size analyzer. Morphology and formation of the particles were studied using Scanning Electron Microscope (SEM). Stability of encapsulated and uncapsulated LPO was studied at 4 °C during 70 days. Results: After purification and purity measurement by SD-SPAGE, concentration of 0/28 micrograms per liter for each of the fractions was obtained. Microencapsulation efficiency was 84% and microcapsules less than 200 nm were formed. Observation by SEM confirmed the formation of microparticles. Microcapsules have a relatively smooth surface, spherical with low tenacity as well. Stability of encapsulated enzyme at 70 days was obtained 81%. Conclusions: Immobilization of Lactoperoxidase extracted from camel milk using sodium alginate is a good method to increase performance of the enzyme.
Show more [+] Less [-]Comparison of prevalence of cna (collagen binding) and fnb (fibronectin binding) adhesion genes among Staphylococcus aureus isolates from clinical specimens and food origin
2016
Ghorbanpoor, Masood | Sheikhi Alizadeh, Khadijeh | Fazlara, Ali | Goraninejad, Saad | Seyfi Abad Shapouri, Masoud Reza | Gharibi, Darush
BACKGROUND: Staphylococcus aureus (S. aureus) possess a variety of virulence genes that are involved in the pathogenesis of infections caused by this agent. OBJECTIVES: The aim of this study was to evaluate the prevalence of the genes encoding collagen binding (cna) and fibronectin binding (fnb) adhesion factors in Staphylococcus aureus isolates from food and clinical specimens. METHODS: During the time period 2010-2013, a total of 38 isolates of Staphylococcus aureus from clinical specimens and 32 isolates from food samples were collected. All isolates were identified biochemically and subjected to DNA extraction. The accuracy of DNA extraction from each isolate was confirmed by PCR amplification of aroA gene and then the presence of cna and fnb genes in the extracted DNAs was assessed by PCR, using the specific primers. RESULTS: The results showed that among 38 isolates from clinical specimens, 15 (39.5%) & 32 (84.2%) and among 32 isolates of food origin 10 (31/2%) and 16 (50%) isolates had cna and fnb genes respectively. Thirteen clinical (34.21%) and 6 food isolates (18.7%) were positive for both fnb and cna genes and 4 clinical (10.5%) and 12 food isolates (37.5%) were lacking both genes. CONCLUSIONS: According to the results, it is concluded that, although these adhesion genes are not present in all Staphylococcus aureus clinical isolates, but their prevalence is high and using the products of these genes in vaccines may be effective in protecting against infections caused by this bacterium.
Show more [+] Less [-]Study of BuLA-DRB3 polymorphism in Khuzestan river buffaloes
2016
Ranjbar, Mohammad Mehdi | Nikbakhat Brujeni, Gholamraza | Ghadrdan Mashhadi, Alireza | Dabbaghyan, Mehran
BACKGROUND: Major histocompatibility complex (MHC) comprises a group of genes, which plays a central role in immune response. The exon 2 of BuLA-DRB3 is part of the MHC class II in buffalo that highly polymorphic, found to be associated with resistance/susceptibility to infections and also with production parameters. OBJECTIVES: The purpose of the present study is to identify BuLA-DRB3 polymorphism in Khuzestan buffaloes and compare this population with other Iranian and world buffalo populations. METHODS: Blood samples were taken from 136 unrelated Khuzestan river buffaloes. After DNA extraction, second exon of BuLA-DRB3 was amplified by the seminested PCR method. Then, the fragments produced by amplifying second exon were cut by RsaI restriction enzyme according to van Eijik method. In the following, allelic frequencies, genotype frequencies, expected and observed homozygosty and heterozygosity were calculated. RESULTS: In restriction fragment analysis 13 and 24 different allelic and genotype patterns were identified for RsaI restriction enzyme, respectively. 10 out of 13 alleles were previously reported. The most frequent genotype was oo)0.1691) and then followed by hh (0.1544) ,ll(0.1103), lw (0.0955), lh (0,0808), ha (0.0661) and lo (0.0514). Also four most frequent alleles were o (0.2721), h (0.2316),l (0.2316)and w (0.1176), respectively. These seven genotypes and four alleles form 72.76% and74.29% overall genotype and allele frequency of population. In addition, estimation of heterozygosity/homozygosty and deviation from Hardy-Weinberg equilibriumofcorresponding population revealed observed homozygosty is more than heterozygosity and departure of population from Hardy-Weinberg equilibrium. CONCLUSIONS: The results indicated that exon 2 of the BuLA-DRB3 gene is highly polymorphic among Khuzestan buffaloes and although, there is differences between buffalo’s genetic polymorphism of distinct world regions, Khuzestan buffaloes’ population is similar to Egyptian buffaloes’ population.
Show more [+] Less [-]Isolation, purification and anti-bacterial property of calprotectin from bovine neutrophil
2016
Imani, Mahdi | Tukmechi, Amir
BACKGROUND: It is believed that bovine neutrophils contain several peptides and protein which exhibit antimicrobial activity against microorganisms such as fungi and bacteria. Objectives: The purpose of this study was to isolate and purify a potential antibacterial protein from bovine neutrophil and test its anti bacterial activity. Methods: Neutrophils were isolated from bovine blood using dextran sedimentation and centrifugation on Ficoll-Hypaqe. Cell viability is examined by trypan blue dye exclusion method. Protein extract was then dialyzed and applied onto ion exchange chromatography for further purification, and its potential cytostatic activity was examined against Staphylococcus aureus, Aeromonas hydrophila and Yersinia ruckeri. Results: Viability of isolated neutrophil was over 95%, chromatographic results and SDS-PAGE analysis exhibited that neutrophil cytosolic proteins were fractionated so that the purification of P7/P23 was almost 60% in the first step and purification was completed in the second phase. Using calibration curve according to molecular mass markers, the relative molecular mass of P7 and P23 determined as 7 kDa and 23 kDa, respectively. Also, results showed that this protein has antibacterial activity and has higher bactericidal activity against Y. ruckeri. Conclusions: It could be concluded that purification of P7/P23 sustains its biological activity and has wide range antibacterial activity. Moreover, taking all data into account may suggest that the cytostatic activity of neutrophil, to some extent, results from P7/P23 protein which is abundant in the cytosole.
Show more [+] Less [-]Analysis of residual genomic DNA in crude and refined soybean oil using three different DNA extraction methods
2016
Nemati, Ghazal | Kamkar, Aboulfazl | Eckert, Brigit | Akhondzadeh Basti, Afshin | Noori, Negin | Ashrafi, Iraj | Shayan, Parviz
BACKGROUND: Soybean oil is one of the highly consumed vegetable oil worldwide. Nowadays, usage of genetically modified (GM) soybean seeds for soybean oil production is constantly increasing. The recommended methods for GMO detection are based on analysis of residual DNA in vegetable oil and highly processed food. However, the successful amplification of isolated DNA depends on the efficiency of DNA extraction method. Objectives: The purpose of this study was to apply three different DNA extraction methods for analysis of residual genomic DNA in crude and refined soybean oil to obtain high pure of DNA suitable for DNA amplification. Methods: Extraction methods were developed based on the specific binding of DNA molecules to the silica membrane (column) or resin. The isolated DNA was then analyzed by PCR technique using primer pairs, derived from 18S rRNA and 5.8S rRNA gene and soybean lectin gene. Results: The results showed that amplifiable DNA could not be extracted from crude/refined soybean oil in method 1. In method 2, by pre-treating of oil with PBS and subsequent precipitation with Isopropanol, the amplification was not observed but OD260 was decreased. In method 1 and 2 the DNA was not pure enough to be amplifiable. To remove more effectively contaminant, method 2 was combined with chloroform extraction as method 3. The extracted DNA from all examined oil samples could be amplified. ConclusionS: We believe that the purity of DNA in samples is decisive for amplification and not necessarily the low amount of DNA in samples. Method 3 can be determined as a suitable method for the isolation of the pure DNA.
Show more [+] Less [-]The effect of rosemary oil extract (Rosmarinus officinalis) on growth parameters and gut morphology of beluga juveniles (Huso huso)
2016
Haghjou Jahromi, Mojtaba | Ebrahimi, Isa | Nematollahi, Amin
BACKGROUND: In recent years, use of herbs as dietary irritant growth factors and replacing it with artificial materials in aquaculture is discussed. Rosemary (Rosmarinus officinalis) oil is one of herbal medicines which its antioxidant and antibacterial properties have been proved in humans and animals. So it can be an alternative option in order to achieve artificial growth stimulants properties. OBJECTIVES: The purpose of this study was to investigate the effect of different levels of rosemary oil as a medicinal herb on growth parameters and gut morphology of beluga juveniles (Huso huso). METHODS: Six groups (three replicate/group) of 126 fish with initial mean body weight of 130.94 ± 5.28g were fed with diets containing 0 (control), 0/01, 0/1, 1 and 2 % of rosemary oil and a group of oxytetracyclin (30mg/kg) for 8 week. At the end of the trial, the growth parameters (final weight, specific growth rate and feed conversion ratio) were calculated. Then, beluga intestinal biopsy was performed and the mean villi length, width and surface were measured in the treatments. RESULTS: Significant increase were observed in villi length (2/25±0/11mm), width (0/52±0/01mm) and surface (1/17±0/07mm) in fish fed with diets containing 1ml/kg rosemary oil (p<0/05). There were no significant differences in growth parameters between treatments. CONCLUSIONS: According to the significant increase of beluga intestinal absorption area and slight improvement of growth parameters in fish fed with diets containing rosemary extract compared to the control group, it seems that rosemary oil can act as a growth stimulant. So it can be considered as an alternative to artificial growth stimulants in aquaculture industry.
Show more [+] Less [-]The effect of anise seed powder (Pimpinella anisum) on performance, nutrient digestibility and infectious microbes of suckling calf intestine
2016
Asemi Esfahani, Mahdi | Chaji, Morteza | Eslami, Moosa | Mohammadabadi, Tahereh | Babai, Mehdi
BACKGROUND: Excessive use of antibiotic growth promoters leaded in the creation of antibiotic-resistant bacteria and by consuming animal products, humans are at risk of receiving their residual. Therefore, instead of using antibiotics as growth promoters, some alternatives must be identified and introduced to animal breeders. Objectives: The purpose of this research was to study the effect of anise seed on performance, digestibility, and infectious microbes in the intestine of suckling calves. Methods: Twenty four female Holstein calves with average weight of39.8±3.8kg from the fourth day after birth to two weeks after weaning were examined in a completely randomized design to evaluate the effects of anise powder on dry matter intake, weight gain, age and weight of weaning, feed conversion ratio, apparent digestibility of dry matter, NDF and ADF, and intestinal infectious and harmful bacteria. The diets were: 1- Control, 2- 0.25% and 3- 0.5% anise/DM of diets. Results: Dry matter intake of calves did not affected by diets (p>0.05). At 70 days old the final weight of calves that consumed diets containing 0.25% and 0.5% of anise was significantly more than control diets. There was no significant difference between diets for the mean of total weight gain in whole period of experiment. The digestibility of NDF and ADF after weaning for diets contain anise was significantly more than control diet (p<0.05). Feed conversion ratio did not affected before weaning, but after weaning significantly improved compared with the control group for diet contain 0.25% and 0.5% anise (p<0.05). The age and weight of weaning were not affected by treatments. The Ammonia and pH of rumen fluid showed increase for anise diets compared with the control group (p>0.05). The adding of anise to the diets resulted in significantly decrease of E.coli of intestine of calves. Conclusions: Therefore, use of anise seed as a medicinal herb additive improved the performance of calves. Also, with the decline of E.coli population had beneficial effect on animal health and the environment. So it may be taking into account as good alternative for antibiotics.
Show more [+] Less [-]Effects of plant-based diets on the bacterial counts and bacterial community composition of beluga sturgeon (Huso huso)
2016
Roohi, Maryam | Agh, Naser | Rezazadbari, Mahmood
BACKGROUND: In recent years, many studies have been conducted on finding a suitable replacement for fish meal to supply the needs of aquaculture feed industry. Objectives: The present study was performed to examine the effect of replacing fish meal and fish oil with plant sources on bacterial counts in intestinal contents and mucus and bacterial composition in Beluga sturgeon. Methods: Beluga sturgeons with a mean initial weight of 133±5 g were distributed into 18 (300 L) tanks (30fish/tank) and were fed experimental diets for 60 days. The control diet contained only fish meal and fish oil as the primary source of protein and lipid, while the experimental diets contained 0, 40, 60, 80 and 100 percent plant protein sources (wheat gluten, corn gluten and soybean meal) and 20% vegetable oil blend (canola, sunflower, cotton and safflower oils) respectively. Results: Results showed that replacement of 80% fish meal and fish oil with plant sources didn’t have significant effect on final weight (235 ± 17 g) compared to control group (256.1 ± 10 g) in a 60 days trial. Replacement of fish meal with 100% plant proteins in combination with 80% vegetable oils resulted in significantly lower final weight (225.7 ± 11 g), compared to other treatments including control group (p<0.05). Replacing 80% fish oil with vegetable oils resulted in a significant reduction of bacterial count in intestinal contents and a significant increase in percentage of Entrobacteriacea sp. However, no significant differences were detected in bacterial counts of mucus in experimental treatments compared to control (p>0.05). Replacement of 60, 80 and 100% fish meal and 80% fish oil with plant sources significantly decreased bacterial counts in intestinal contents and intestinal mucosa compared to control group (p<0.05). Also this replacement cause significant change in bacterial composition of intestine. Conclusions: The results suggested that using plant sources in juvenile Beluga sturgeon diet decreases the bacterial count in the intestinal contents and mucus and changes the composition of intestinal micro flora.
Show more [+] Less [-]The effect of nanocopper and mannan oligosaccharide supplementation on nutrient digestibility and performance in broiler chickens
2016
Sabet Sarvestany, Shahin | Resvani, Mohammad | Zamiri, Mohammad Javad | Shekarforoush, Shahram | Atashi, Hadi | Mosleh, Najmeh
BACKGROUND: Following the ban on the use of growth stimulant antibiotics in many countries, interest has arisen in finding a suitable alternative for antibiotics in poultry production. OBJECTIVES: The aim of this study was to investigate the effect of supplementation of two levels of nano-copper (0 and 100 mg/kg) and two levels of mannan oligosaccharide (0 or 1 g/kg) as natural growth stimulants on digestibility of nutrients and performance in broiler chicks. METHODS: At the end of the second week of breeding, 160 Cobb-500 broiler chicks were assigned in four treatment groups. For each treatment, four replicates (10 chicks per replicate) were considered. Experiment was conducted as a 2×2 factorial model in a completely randomized design. Results: No significant differences in digestibility of nutrients and growth performance between birds that ate the supplements with control group were observed (p>0.05). CONCLUSIONS: Mannan oligosaccharides and nano-copper on growth performance and nutrient digestibility in broiler chicks had no significant effect. At the doses used, concomitant supplementation of copper and mannan oligosaccharide did not have a positive effect on traits that were studied in broilers.
Show more [+] Less [-]Comparison of the effects of selected cyclooxygenase enzyme inhibitors on airway responsiveness to histamine and acetyl choline in an experimental model of allergic asthma in guinea pig
2016
Keshavarz, Hossein | Rassouli, Ali | Sadeghi Hashjin, Goudarz | Sassani, Farhang | Moein, Mostafa | Tabarraei, Hadi | Ghaffari, Sepideh
BACKGROUND: Aspirin-induced asthma (AIA) with symptoms such as acute bronchoconstriction occurs in about 10% of asthmatic individuals following ingestion of aspirin or other aspirin-like drugs. The mechanisms involved in AIA are not fully understood but it seems that inhibition of cyclooxygenase (COX) can play a role in such attacks. Objectives: This study aimed to compare the effects of aspirin-like drugs on airway responsiveness in an animal model of allergic asthma. Methods: 42 male guinea pigs (250-300 g) were randomly divided into seven groups: control, allergic, ketoprofen, indomethacin, celecoxib, and aspirin (high and low doses). All animals except control group were sensitized by i.p. injections of ovalbumin and Al (OH)3 suspensions and then challenged by inhalation of ovalbumin solution on day 18. The animals received three oral doses of the aforementioned drugs or normal saline in control and allergic groups with 12 hr intervals within 24 hr before ovalbumin challenge. On day 19, animals were euthanized and the responsiveness of isolated tracheas was studied using cumulative doses of histamine and acetyl choline in an organ bath. Results: Indomethacin and ketoprofen significantly increased the trachea responsiveness to acetyl choline and histamine at all concentrations. Emax values for acetyl choline and histamine in indomethacin were respectively (3.5±0.1, 3.5±0.1 g) and ketoprofen (5.1±0.2, 4.3±0.1) groups were greater than those of control (1.5±0.1, 1.5±0.1), allergic, celecoxib, high dose aspirin and low dose aspirin groups (p<0.05). Conclusions: It was concluded that indomethacin and ketoprofen (but not aspirin and celecoxib) can exacerbate the asthmatic conditions in this animal model.
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