خيارات البحث
النتائج 51 - 60 من 190
INFLUENCE OF YEAST EXTRACT ON GENE EXPRESSION OF CRWRKY1 AS A REGULATORY GENE IN ALKALOIDS PATHWAY IN CATHARANTHUS ROSEUS (L.) G. DON
2018
Mona Moghazee | Fatma Badway | Rania Younis | S. Hassanein
Catharanthus roseus (L.) G. Don is a medicinal plant rich in many alkaloids that are used in treatment of many diseases. It is unique in the production of vinblastine and vincristine compounds, which are used in treatment of several cancers. There are many genes in the biosynthesis pathway that produce these anti-cancer compounds, including the gene Crwrky1 which is a regulatory gene that codes for the transcription factor in the monoterpene indole alkaloid (MIA) pathway. In this study, the effect of yeast extract on crwrky1 gene expression levels from treated calli was studied. Quantitative RT-PCR (QRT-PCR) using SYBR Green I/ROX was used to analyze the changes in the expression level of this gene in response to different treatments of yeast extract. Crwrky1 expression increased to 3.6 folds in treated callus obtained under 0.4 mg/l yeast elicitor for 4 hours (YE2) treatment to compare with the control (untreated) callus.
اظهر المزيد [+] اقل [-]APPLICATION OF SALMONELLA PHAGE COCKTAIL TO CONTROL SALMONELLA TYPHIMURIUM IN VITRO
2018
Yasmer Hussein | Kh. El-Dougdoug | B. Othman
Members of the genus Salmonella are among the microbial pathogens associated with dangerous infection. The increased of Salmonella spp. antibiotic resistance has propelled the need of alternate therapeutic methods or strategies. Bacteriophage forms one of these alternate strategies. Six lytic bacteriophages infecting Salmonella Typhimurium were isolated from sewage drain water. Phages were purified biologically by single plaque assay and concentrated using the ultracentrifugation. The phage isolates were named Ø SM, Ø SF, Ø SG, Ø SP, Ø SA and Ø SD. Morphological characters of Salmonella phages showed that all the phage isolates belong to family Myoviridae. All phage isolates were highly stable at room temperature, storage at refrigerator temperature and had thermal inactivation point ranged from 90 to 98 °C. Phages were stable at pH conditions ranging from pH 4 to 12. Phages did not lose their infectivity after exposure to UV for 90 min. at 35 cm and 53 cm distance. The host range of the isolated phages was found that the phages had narrow host range. Phage cocktail with different MOI was used to control Salmonella Typhimurium in vitro. Data revealed that addition of phage cocktail at MOI 10 reduced the Salmonella cells with rate 98.2 % after 4 hrs. from addition. introduction Salmonella spp. belong to family Enterobacteriaceae and widely distributed in nature and often found in the intestinal tract of warm-blooded animals and humans,where they asymptomatically colonize and multiply (Newell & Fearnley, 2003 and Doyle & Erickson, 2006). More than 2,500 serotypes of Salmonella exist and the most prevalent and important Salmonella enterica serotypes reported worldwide are Enteritidis and Typhimurium. These are responsible for 99 % of Salmonellosis in humans and warm-blooded animals. The most common symptoms of Salmonella infection is non-bloody diarrhea and abdominal cramps (Bell and Kyriakides, 2002). Due to foodborne infections by Salmonella are obtained through ingesting contaminated food or water, (Abd El-Aziz, 2013 ) detected high incidence of Salmonella Typhimurium , one of the most frequently isolated serovars from food borne outbreaks throughout the world, in retail raw chicken meat and giblets in Egypt. Bacteriophages are considered an effective weapon against pathogenic bacteria. As a result of development resistant bacteria against antibiotics because of their repeated usage, bacteriophages are used as a safe alternative to control pathogenic bacteria (Abramia et al 2016). In addition, offer a great advantage over antibiotics. First, bacteriophages are specific and target only the pathogens of interest, so the normal gut microflora are not affected. Second, bacteriophages are self-replicating in the bacterial host and lyse bacteria. (Connerton and Connerton, 2005). This paper aims to investigate the incidence of lytic bacteriophages specific for Salmonella in sewage water and study the posibility of their application for controling the Salmonella in vitro.
اظهر المزيد [+] اقل [-]EFFECT OF SEASON ON GROWTH PERFORMANCE AND IMMUNITY TRAITS IN RABBITS
2018
Yasmein Abdel-Ghafar | I. El-Wardany | Marwa Abdo | Samah Darwish | E. Abd El-Kafy
The present study was carried out to investigate the effect of season on growth performance traits, leptin hormone concentration and gene expression for innate immunity in response to vaccination against pasteurellosis. A Total of 384 weaned rabbits were used in this study. They were from females of APRI line, a local population. Rabbits weaned at 33-35 days and introduced in the experiment at weaning. Arbitrarily, weight at beginning was considered as the "5 weeks" weight. All rabbits were weighed every 7 days and the feed consumption measured at the same weekly interval until all rabbits were 12 weeks old. Leptin hormone level in serum was assayed. Vaccination with Pasteurella multocida was studied in a challenge experiment. Gene expressions for interleukin-6 (IL-6) and toll-like receptor-4 (TR4) were assayed by Real Time-PCR. Parameters of the antioxidant status were included reactive oxygen species, (ROS) expressed as H2O2, Lipid Peroxide, expressed as malondialdehyde and glutathione peroxidase. Blood samples were taken at 8, 10 and 12 weeks of age, respectively. The body weights in winter at W5, W8and W12 of age were higher than those in others seasons. Season had a significant (P≤0.05) influence on daily gain and feed intake. Season had no significant influence on Leptin hormone level in growing rabbits. Vaccination with Pasteurellamultocida led to an increase in gene expression for IL-6 in autumn and winter. Expression for IL-6 in spring has the lowest values. Gene expression of TR4 in rabbits under different seasons was not significantly different. It is can cluded that vaccination by Pasteurellamultocida needs some additives to enhance immunity especially during summer and spring seasons.
اظهر المزيد [+] اقل [-]APPLIED STUDY OF MICROBIOLOGICAL HAZARDS IN RAW MILK SOFT WHITE CHEESE IN EGYPT
2018
Maha Lotfy | O. Aita | Enas Hassan | Azhar Elsayed
Raw milk Domiati cheese is the main soft white pickled cheese produced in Egypt. The objective of this study was to assess the microbiological hazards, physiochemical quality and safety of some raw Domiati cheese subtypes including Double Cream, Tallaga, Baramely and Istanbully. The cheese samples were randomly collected from different cheese retailers in Cairo. The results indicated that the protein content and fat content were high in Double cream cheese. The pH value was low in Baramely cheese. Total solid, ash, and EC were high in Istanbully cheese because it is high salt level. Also, results indicated high microbiological hazards. the cheese samples were highly contaminated, having microbial load exceeding the acceptable limits such as: Total bacterial count, Total coliform, Fecal E. coli and yeast & molds. Pathogenic bacteria (Staphylococcus aureus, E. coli O157:H7, Salmonella sp., Shigella sp., Listeria monocytogenes, Bacillus cereus and Campylobacter jejuni) were detected in three cheese samples. Except Istanbully cheese sample were found free of most pathogenic bacteria. A high microbial load of the cheese samples present a public health hazard to the consumers and emphasize the need for improving hygienic standard. Microbiological hazards must be limited to the stander limit of food safety. Raw milk soft white cheese must be manufactured according to hygienic standard.
اظهر المزيد [+] اقل [-]GENOTYPIC VARIATIONS IN SALT TOLERANCE OF SOME EGYPTIAN WILD BEET ACCESSIONS
2018
S. Hussin
This study reports for the first time the eco-physiological responses of some Egyptian wild beet accessions (WB1013, WB1021 and WB1026) under saline irrigation. The plants were exposed to five seawater salinities (0, 20, 30, 40 and 60% sws) for 6 weeks in a sandy culture in the greenhouse. Low salinity (20% sws) slightly enhanced the plant fresh weight of both WB1013 and WB1021 genotypes by 5% and 3% respectively, but significantly reduced that of WB1026 genotype by about 10%. Higher seawater salinities, however, caused progressive growth reductions in all accessions, with maximum growth inhibition, being 59% in WB1026 at 60% sws. Tolerance threshold was lowest (being at 20% sws) for WB1026, but highest (reached 40% sws) for both genotypes WB1013 and WB1021. EC50 was at salinity level of 40 – 60% sws for WB1026 genotype, but higher than 60% sws for genotypes WB1013 and WB1021. These indicate that both accessions WB1013 and WB1021 are more salt-tolerant when compared with WB1026. The higher salt tolerance of WB1013 and WB1021 accessions is largely conferred by higher leaf K+/Na+ ratio, due to low Na+ and Cl- accumulation under saline conditions compared to WB1026. This was associated with lower dry weights and ion leakage, and with higher leaf area, chlorophyll readings, total soluble carbohydrates and Ca2+ concentrations when compared with WB1026. Both WB1013 and WB1021 accessions do not only offer the possibility of being an alternative promising cash crops under seawater irrigation, but also, through an understanding of its physiology, may provide possible routes to enhance salt tolerance in other beet crops.
اظهر المزيد [+] اقل [-]ASSESSMENT OF WATER QUALITY IN QARUN LAKE
2018
M. Abu-Ghamja | Y. Zakarya | M. Elbordiny
To assess water quality of Qarun lake, forty-six of lake water samples were collected during the period from 2014 to 2015. Value of pH of Qarun lake ranged from 8.22 to 8.32. Value of alkalinity ranged from 9.8 to 33.4 ppm. ECw values ranged from 26.5 to 40.99 dS.m-1. Qarun lake contained the soluble cations in the following order: Na+> Ca2+> Mg2+> K+. The SAR of the studied water in Qarun lake ranged from 274 to 400with a mean value of 337. The highest value of SAR occurred in season 2015 while the lowest one was in 2014. The hardiness value of Qarun lake ranged from 602 to 1567ppm. The COD values were higher than that of ECP501,2015. they ranged from 1168 to 1293 ppm. Different macro and micronutrients were more than the permissible limits. Water Quality Index (WQI) was applied using ten parameters of water quality (pH, Chloride, Chemical oxygen demand (COD), Iron (Fe), Phosphate (PO4-3), Chromium (Cr), Boron (B), Hardiness, Ammonium and Nitrate ). The results indicated that water quality of Qarun lake decayed from the year 2014 to 2015 and could be categorized into Unsuitable class. The effect of anthropogenic activities was obvious on some parameters such as nitrate and ammonium. Monitoring the water quality of Qaroun lake is necessary for proper management.
اظهر المزيد [+] اقل [-]PRODUCTION OF L-TRYPTOPHAN BY MUTANTS OF CORYNEBACTERIUM GLUTAMICUM
2018
Hamies Mohamed | Ghada El Nady | A. Ali | A. Abdel-Razik | S. Ibrahim
L-Tryptophan, is one of the amino acids, also is one of the 9 essential amino acids of human which cannot be synthesized internally by him, microbial production is the main method for obtaining tryptophan for commercial uses. Typical microorganisms used for tryptophan production are E. coli and C. glutamicum. In this study, random mutations is performed on two strains of C. glutamicum to increase tryptophan production, the produced tryptophan measured by bioassay using tryptophan auxotroph E. coli (JW1254-2) strain, the mutations are performed using UV radiation. To detect and compare the difference between the parent strains and the muted strains genetically two molecular markers were used start codon targeted polymorphism (SCoT) and Inter-simple sequence repeats (ISSR). Tryptophan remarkably increased after C. glutamicum mutation to reach 278.4 µg/ml (1257.4% increment) from one mutated strain. Molecular genetics methods showed an ability to distinguish between the two original strains and their mutants and it showed the importance of the mutation by UV radiation for increasing the productivity of the bacteria to tryptophan.
اظهر المزيد [+] اقل [-]EFFECT OF SPROUTING USING SALINE WATER ON CHEMICAL COMPOSITION AND PROTEIN QUALITY AND FRACTIONATIONS OF EGYPTIAN CLOVER SPROUTS
2018
A. El-Gebaly | Y. El-Gabry | Sanaa Mahfouz | M. Abdallah
The effect of salt stress on growth proximate analysis, amino acid profile, protein quality and fractionations in 3 days etiolated clover sprout samples was investigated. Sterilized and non-sterilized clover seeds were sprouting using tap water 1000 ppm and 2000 ppm NaCl solution. The results showed reduction effect of clover sprout characters with higher NaCl concentration. Clover seed sprouting increased the crude protein content using tap water or saline water for sprouting as compared with dry seeds. However using non-sterilized clover seeds for sprouting recorded the higher values of protein (44.73%), lipids (6.21%) and energy (318.51 kcal/g) in etiolated sprouts, while using sterilized seeds recorded higher carbohydrate (21.28%), fiber (14.57%) and ash (4.46%). For amino acids, aspartic acid followed by glutamic acid were the most abundant, while Cysteine and methionine were the least in clover etiolated sprouts. Using saline water for clover seed sprouting caused increases in all amino acid compared with tap water except Methionine, aspartic acid and cysteine. For protein efficiency ratio (PER), essential amino acid index (EAAI%) and biological value (BV), from using saline water for sprouting had the higher values than sprouts from using tap water, but the values are less than dry seeds. On the other hand nutritional index (NI) recorded the higher values in salt stress compared with both using tap water and dry clover seeds. For protein fraction in etiolated clover sprouts albumin was the major protein fraction extracted from NaCl 2000ppm sprout fallowed by prolamin from tap water sprouts, glutelin from NaCl 1000 ppm sprout and globulin from tap water sprout. The clover sprout protein isolated and its fractions could have excellent applications for future product development by virtue of their nutritional and functional properties.
اظهر المزيد [+] اقل [-]ANALYTICAL STUDY OF SOME ECONOMIC ASPECTS OF WHEAT CROP IN EGYPT
2018
Shereen Abd El-Azem | M. Salem | W. Mojahid | A. Abdel Maqsoud
Wheat crop is considered to be one of the most important grain crops and a major source of food for the Egyptian people. The production and economic indicators of wheat yield were studied in Egypt. It is clear that the total area and production of wheat increased by 71 thousand feddans annually and, 199 thousand tons annually, respectively, at a significant level of 0.01. The coefficient of general trend of area and production were (R2) 0.80 respectively, which means that 87%, 80% of the changes in the total area and production of wheat are due to factors whose effect reflects the time variable. However, the food security factor should be increased to 0.50, as the minimum level of strategic stock security is achieved when the stock meets the needs of the population for at least 6 months. Which is estimate at 6.850 million tons during the period 2000-2015, which is edmivelent storage capacity of wheat, which estimated the average national consumption of wheat during about 13.579 million tons, it is noticed the food security coefficient is low than.
اظهر المزيد [+] اقل [-]AN ECONOMIC EVALUATION OF THE EFFICIENCY OF OPERATING AGRICULTURAL MACHINES IN PRODUCTION OF WHEAT
2018
Aziza Hussein | S. Meqled | Eman Amin | M. Desouqy
Agricultural sector is considered to be one of the most important sectors in the Egyptian economy that contributes greatly in the national income. Therefore, the state pays great intention to the agricultural sector concerning all developmental aspects either vertical or horizontal. That is achieved through developing used and already existing agricultural resources which is called vertical agricultural development, or through adding new agricultural materials which is called horizontal agricultural development. In all of the abovementioned fields, agricultural machines play an important and direct role in achieving both vertical and horizontal agricultural development, as it is well- known that vertical and horizontal agricultural expand depends totally on agricultural machines in general and the developed modern machines in particular. As for vertical agricultural expand, agricultural machines play vital and effective role in increasing production, lowering production costs and the possibility of making use of the advantages and jumps of expansion through expanding in use and application of modern technical methods in agriculture as laser leveling, planting by seed drill, automatic seedling and automatic harvest. In addition to the abovementioned, there is the gab in the cereals, decrease of the net profit of farmers as well as their use of farming traditional methods that do not coop the agricultural development. Considering the importance of the technical standard as an important factor of agricultural production, the use of modern technology comes among the most important methods that may increase the production of Feddans by the optimal economic use of limited resources. The thesis aimed to introduce the best technical standards in agricultural machines applied in the farming rice, wheat and maize in order to yield the highest production with lowest costs and to gain the highest amount of net profit of Feddan. Moreover, the thesis aimed to study the production and economic indicators of the crops studied by the thesis and their development nationwide as well as comparing the effect of the technical processes on the productivity of the Feddan of the crops studied by the thesis and their effect from the economic feasibility point of view. This part of the thesis deals with the economic evaluation of using agricultural machines in order to farm to wheat in Egypt., as it was shown that the average Feddan productivity of wheat was estimated of about 3.7 ton/ Feddan as a result of using technical methods, whereas productivity by using traditional systems was about 2.8 ton/Feddan. This shows that as a result of using technological systems, Feddan productivity overcomes using the traditional systems as that increase was estimated to be about 0.9 ton/ Feddan with a percentage of about 32% from traditional systems. This increase in the average Feddan productivity for land unit reflects to new items, laser leveling, deep ploughing and adding land plaster with the relatively stability of varied production costs and the extent of technical and economic efficiency on favor of using technological systems. The thesis showed that the total proceeds of wheat farmed by using technological systems reached in average about 12440 pound/ Feddan, against 9560 pound/ Feddan for wheat farmed by using traditional systems. It was shown that the total proceeds of wheat farmed by using technological systems increase with a percentage of 30% from the same crop farmed by traditional systems. The study shows that the total varied costs of wheat for technological systems distributed on the production elements is estimated in average of about 3915 pound/ Feddan against 6390 pound/ Feddan for transitional methods with an increase of 39% when using agricultural machines. Moreover, the study pointed out that the total costs were estimated in average of about 5915 pound/ Feddan of wheat farmed by using technological systems against 8390 pound/ Feddan for traditional systems with an increase of about 29%. This illustrates the efficiency of suing technological systems. The study considered the net Feddan proceeds of wheat farmed by technological systems. It was estimated of about 6525 pound/Feddan against 1170 pound/ Feddan for traditional systems. This means that technological systems' net profit exceeds the same profits of traditional systems with an increase of about 5355 pounds. The study showed that the proceeds above the varied costs of wheat farmed by technological systems are estimated with about 8525 pound/ Feddan in average against 3170 pound/ Feddan for traditional systems. This means that technological systems are superior with about 169%. This increase is attributed to the increase in the total proceeds of technological systems comparing to traditional systems. The study shows that the cost of ton of wheat farmed by technological systems is estimated of about 3362 pound/ Feddan in average against 3414 pound/ Feddan for traditional systems. This means that technological systems exceed traditional systems with about 2%. This decrease is attributed to the increase of the Feddan productivity using technological system comparing to traditional systems. Considering the profit on the invested pound, it reached about 1.10 pounds for the use of technological systems against 0.14 pounds for the use of traditional systems. This shows that the technological systems used in farming wheat is better from both technical and economic point of view which means that the new technological systems used in production covers the total costs and realizing a surpass. This shows the efficiency of resource usage in producing wheat farmed by technological systems. Every pound being spent or invested in farming using technological systems achieves an income of about 10 pounds against one pound for traditional system.
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