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REUSE OF WASTE DRAINAGE WATER AFTER ITS TREATMENT USING PGPRS TO IRRIGATE SOME HORTICULTURAL CROPS
2018
Marwa Kahlil | Wedad Eweda | M. Omar | Mona Orabi | K. Imam
Natural sources of water are limited in Egypt. The rapidly growing populations necessitate continuous expansion of the cultivated area. This means an increase of the gap between the demands of water for irrigation and the limited water supply. Looking for other sources such as low quality water like (industrial effluent, drainage and sewage) must be used in irrigation of some garden and wood plants. This investigation was conducted on agricultural drainage wastewater from El Mohete drain (Marioteya Canal) west of Cairo; the samples were collected from different places during (Summer and Winter seasons). The wastewater contaminated with pathogenic microorganisms, the excess of fertilizers (inorganic & organic), heavy metals, and the residuals of pesticides. Plant Growth Promoting Rhizobacteria (PGPR) could remediate the wastewater as biological bioremediation to remove some pollutants such as pathogenic microorganisms, heavy metals and pesticides. Chemical remediation was used as nitrification inhibitor to stop transformation of ammonia to nitrate. This work was conducted to study the ability of PGPR strains e.g. Bacillus megaterium, Bacillus subtillis, Bacillus circulans, Paenibacillus polymyxa, Pseudomonas floresense, Serratia sp. and Azotobacter chroococcum 5, 9 and 23 to treat the drainage water for irrigation the Mentha viridis cv. and Gladiolas grandiflorus cv. plants. Two pot experiments were conducted in greenhouse. The treatments were applied as follows; Natural water, treated water and drainage water to irrigate the plant. Use the PGPR as inoculants and thiourea as nitrification inhibitor, Heavy metal treated was (Copper, Cobalt, Zinc, Cadmium and Mercury) the result showed us heavy metals removal by PGPR from drainage water. The characterizations of PGPRs as shown in the obtained results are they could enhance plant growth by using their own metabolism (solublizing phosphate, producing hormones or fixing nitrogen) as well as correlation of them with the potenit of effects on the growth of plants in unfavorable conditions in order to improve the efficiency of phytoremdiation of contarinated soils. The removal of heavy metals and the elimination of pesticides residues were markedly noticed in this investigation. Results also confirmed the ability of PGPRs in suppressing the effect of pathogenic bacteria like Salmonellasp and E.coli. These abilities are of great importance in terms of plant and soil health. Consequently, the role of PGPRs bacteria associated with plant rhizosphere in remediation of water and soil contaminations due to its biochemical activity and thus, stimulate plant growth is a great important subject in phytoremediation process nowadays.
显示更多 [+] 显示较少 [-]BIOLOGICAL ACTIVITY AND DISINFECTION OF ANOSAN SOLUTION WITH INHERENT APPLICABILITY 1- INACTIVATION OF PATHOGENIC MICROORGANISMS
2018
Issa Lootah | A. Abdelhamid | S. Galal | Lamis Harib | M. Hoehn | A. Langner | K. El Dougdoug
The pathogenic and spoilage microorganisms affect human health directly or indirectly and become increasingly important in most countries. Novel antimicrobial agents and disinfectants have become necessary due to the rise of antibiotic resistance phenomena. The current study investigate the inhibitory infect of ANOSAN on pathogenic bacteria and toxigenic fungi. Chemical analysis was performed for ANOSAN. The antimicrobial activity of ANOSAN was carried out using agar well diffusion assay and mean growth inhibition percentage and Minimum Inhibitory Concentration (MIC). The antibiofilm activity was conducted using Biofilm formation assay and the impact of the disinfectant on the preformed biofilm was visualized by Scanning Electron Microscope (SEM). The chemical composition of ANOSAN comprised very low amount of Sodium (0.034%), Chloride (0.01%), Hypochlorite (0.014%) and Organic matter (0.0062%). ANOSAN low concentration showed a broad spectrum of antibacterial activities against Gram positive, Gram negative bacteria and fungi. The MIC (0.781 mg/ml) was observed for Vibrio cholerae, Pseudomonas aeruginosa and Staphylococcus aureus. Sub-inhibitory concentrations of ANOSAN have successfully inhibited biofilm formation of the above mentioned bacterial patho gens. The ANOSAN appeared to be effective as bactericidal against Ps. aeruginosa and Staph. aureus. The time kill assay was observed between (0-6h) and between (0-3h) of exposure for both pathogens, respectively, and the viable bacterial counts remained undetectable after the previous time in a confirmatory experiment. Scanning Electron Microscopy (SEM) was conducted to confirm the antimicrobial activity of ANOSAN against Staph. aureus and Ps. aeruginosa. These data directly illustrate the destructive effects of the ANOSAN on the pathogenic bacteria. This work clarified that ANOSAN water had bactericidal and fungicidal activity along with inhibiting the ability of pathogenic bacteria to form biofilms, thus providing a good alternative to the use of traditional antimicrobials in food industry, pharmaceutical and medical applications.
显示更多 [+] 显示较少 [-]SCREENING OF SOME EGYPTIAN PLANT EXTRACTS FOR BIOLOGICAL ACTIVITY AGAINST SOME PATHOGENIC BACTERIA
2017
Nermin Abdel-Hamid | Hanan Abdel-Khalek | Z. Mattar | Khadiga Abou-Taleb | El. Ramadan
Plants and plant by-products are now gaining attractiveness in treatment of bacterial infections and food preservation. The objective of this study was to assess antibacterial activity of some Egyptian plant and plant by-products against the locally pathogenic isolates from patients having infectious diseases in our country. Screening of antibacterial activity of ethanol, methanol and hexane extracts of some plants: grape leaves (Vitis vinifera), mulberry leaves (Morus alba), mallow leaves (Corchorus olitorius) and lemon leaves (Citrus limon) toward Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella sp., were investigated. Antibacterial activity was performed by the agar disc diffusion method. The ethanol and methanol extract of tested plant leaves showed promising antibacterial activities against both Gram-positive and Gram-negative tested bacterial isolates due to its great ability to extract those polyphenolic and biological active compounds from natural sources which effectively act against broad spectrum bacteria. Ethanol followed by methanol were found to be the best solvents of choice to extract natural products to get maximum health and medicinal benefits. The results revealed that the extraction efficiency increase with polarity increasing of the solvents, hence the highest extraction done with ethanol and methanol and the lowest extraction with nonpolar solvent n-hexanedid not exhibit any activity against all the tested bacteria. Irradiation at 5 and 10 kGy did not significantly affect the antibacterial activity of all tested plant leaves. Results indicate the potential of these plants for further work on isolation and characterization of the active compounds responsible for antibacterial activity and its exploitation as therapeutic agents
显示更多 [+] 显示较少 [-]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.
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