Papers by Ahmed Abdel-Megeed
Agriculture
Around the world, salinity a critical limiting factor in agricultural productivity. Plant growth ... more Around the world, salinity a critical limiting factor in agricultural productivity. Plant growth is affected by salt stress at all stages of development. The contemporary investigation focused on Chaetomorpha antennina aqueous extracts (SWEs) to decrease the effects of salt strain on rice germination, growth, yield, and the production of key biological and biochemical characters of the rice, Oryza sativa L. (Poaceae). SWE improved the germination capacities of rice seedlings by promoting their emergence 36.27 h prior to those that had been exposed to saline stress. The creation of 79.647% longer radicles by SWE treatment on salt-stressed seeds which boosted the establishment effectiveness of seeds produced under salt stress longer radicles resulted in plants that were 64.8% taller. SWE treatment was effective in revoking the levels of protein (26.9%), phenol (35.54%), and SOD (41.3%) enzyme levels that were previously constrained by salinity stress. Additionally, SWE were also effic...
хирургическое лечение обширных врожденных кавернозных гемангиом у новорожденных детей
Общероссийская общественная организация «Российская ассоциация детских хирургов», 2011
Scientific Reports, 2022
The purpose of this study was to test the nematicidal activity of extracts of two marine algae (C... more The purpose of this study was to test the nematicidal activity of extracts of two marine algae (Colpomenia sinuosa and Corallina mediterranea) and their synthesized silver nanoparticles against root-knot nematodes (Meloidogyne incognita) that infest tomato plants. Scanning electron microscopy (SEM) revealed that nanoparticles had aggregated into anisotropic Ag particles, and transmission electron microscopy (TEM) revealed that the particle sizes were less than 40 nm. Fourier Transform Infrared Spectroscopy (FT-IR) analysis revealed that the obtained nanoparticles had a sharp absorbance between 440 and 4000 cm−1, with 13 distinct peaks ranging from 474 to 3915 cm−1. Methylene chloride extracts and nanoparticles synthesized from both algae species were used to treat M. incognita. C. sinuosa nanoparticles had the highest nematicidal activity of any treatment. Furthermore, and in contrast to other treatments, C. sinuosa nanoparticles reduced the number of nematode galls, egg-masses per ...
Escherichia coli and entomopathogenic bacteria (G +) Bacillus thuringeinsis on the mulberry silkw... more Escherichia coli and entomopathogenic bacteria (G +) Bacillus thuringeinsis on the mulberry silkworm, Bombyx mori (Lepidoptera: Bombycidae). We used bioassay and molecular markers linked to 5 th instar larvae to inject bacterial and analyze the response of B. mori. Also, the effect of both bacteria on the total and differential haemocytes count of the 5 th instar larvae of B. mori was evaluated. Results revealed that injection with E. coli increased the total haemocytes counts (THCs) to about 59.09% of the control at 24 h post-infection. In this respect, B. thuringeinsis decreased the THCs by about 45.9, 58.39 and 69.4%, respectively, than control after 48 h post-infection at concentrations of 0.5, 1 and 1.5 ppm. Injection with E. coli increased the number of Pr, Pl, Gr and Oe. On the contrary, injection with B. thuringeinsis significantly decreased the number of Pr, Pl and Gr and Oe. The mutagenic effect of the bacterial injection produced and/or affected several proteins that kill...
Asian Journal of Chemistry, 2014
Starting from 4-substituted-phthalazin-1(2H)-one (1), A series of new 2- (5,6-dihydro-4H-1,2,4-tr... more Starting from 4-substituted-phthalazin-1(2H)-one (1), A series of new 2- (5,6-dihydro-4H-1,2,4-triazolo[4,3-a]benz[f]azepin-1-yl)methyl)-4-substituted phthalazin-1(2H)-ones derivatives ( ) have been synthesized. The structure of synthesized new compounds was established by spectral data and screened for their antimicrobial activities against various bacteria and fungi strains.
Abstract: A study was undertaken to detect and monitor the degradation of two organophosphorous p... more Abstract: A study was undertaken to detect and monitor the degradation of two organophosphorous pesticide residues (dimethoate and malathion) by four plants namely Amaranth, Amaranthus caudate, Lettuce, Lactuca sativa, Water cress, Nasturtium officinale and Kidney bean, Phaseolus vulgaris and microbial degradation based on the recommended rates for insects control in Kingdom of Saudi Arabia. Pesticides residues were quantified by gas chromatography mass spectrometry (GC-MS) analysis. The ability of these biological agents to detoxify and clean up these pesticide residues in both soil and plants was studied. In soil samples, the highest percentages of malathion-degradation were ≥60 and ≥90 % after 28 and 42 days, respectively. The half-life times of malathion were accounted by 24, 23, 25 and 25 days for Amaranth, Kidney bean, Lettuce and Watercress, respectively. For dimethoate, results of time course studies in soil degradation revealed that Amaranth and Kidney bean were the most ef...
Development and evaluation of castor oil nanoemulsion on the cotton leaf worm Spodoptera littoralis (Boisd.) and its adverse effects on the reproductive system of albino rats
Biomass Conversion and Biorefinery, 2022
African Journal of Microbiology Research, 2012
significantly increased shoot length and leaf area of maize either alone or in combination with N... more significantly increased shoot length and leaf area of maize either alone or in combination with N-fertilizer at 50 and 100 kg N/ha. Combination of biofertilization and N-fertilization, especially at 100 kg N/ha had more effect on the growth of maize compared to the biofertilization alone, as well as nitrogenase activity. Key words:
A unique approach of the degradation of organophosphorus pesticide dimethoate in aqueous media wi... more A unique approach of the degradation of organophosphorus pesticide dimethoate in aqueous media with Effective Microorganisms was investigated. These microbial consortia could tolerate to about 120 mg mL -1 of dimethoate technical grade. Several factors influencing dimethoate degradation were investigated. The growth rate µ (h -1 ) of these effective microorganisms was ca. 0.925. The acetonitrile extracts of the Effective Microorganisms cultures were subjected to gas liquid chromatography (GLC) using two different solvent systems: hexane-chloroform methanol and cyclohexane-acetone-chloroform. GLC analyses revealed the complete degradation and disappearance of dimethoate after 3 days. However, the precise conditions for this pesticide degradation were not fully understood. Change in pH of culture medium to acidic range supported the biological transformation of the compound. Optimal growth conditions were 8.5 and 27°C for pH and temperature, respectively. Two isolates from these microbial consortia lost their ability to utilize the dimethoate. The intermediate compounds were also metabolized, further resulting in complete mineralization of dimethoate. These Thus, the present study establishes the EM degradation of dimethoate and also suggests their role in the bioremediation of other pesticides contaminated water.
Fresenius Environmental Bulletin, 2016
This study aims to examine the influence of the work environment on employee performance mediated... more This study aims to examine the influence of the work environment on employee performance mediated by work discipline. It is quantitative research with questionnaires as the data collection method. Data were analyzed by using Path Analysis. The populations are all of the full-time employees, and seventyeight respondents of them were selected by saturated sampling method. The study shows that the work environment affects employee performance, and work discipline mediates the effect of the work environment on employee performance.
Biodegradation of polluted temperate and cold temperature environments may require the activity o... more Biodegradation of polluted temperate and cold temperature environments may require the activity of psychrophilic and psychotrophic bacteria, because their low temperature growth range parallels the ambient temperatures encountered in these environments. In this present study a mixed population of microorganisms from an ice sample from Spitzbergen was cultivated by enrichment culture technique which exhibited high efficiency to assimilate and mineralize C10 to C22 n-alkanes as the sole source of carbon and energy at both 4 and 20°C. Pseudomonas frederiksbergensis was isolated from this mixed culture, characterized and identified according to the cell wall fatty acids analysis and 16S rDNA sequence. The isolate was psychrophilic, with a growth temperature ranging from 4 to 20°C, an optimum growth temperature of 15°C and an optimal pH of 7. _____________________________________________________________________________________________________________
Genotoxicity assessment of amino zinc nanoparticles in wheat (Triticum aestivum L.) as cytogenetical perspective
Saudi Journal of Biological Sciences, 2021
Orofaziale Schmerzen. Ein Fallbeispiel zur Behandling temporomandibulärer Funktionsstörungen in der Praxis
Quintessence International, 2000
Orofaziale Schmerzen. Ein Fallbeispiel zur Behandling temporomandibularer Funktionsstorungen in d... more Orofaziale Schmerzen. Ein Fallbeispiel zur Behandling temporomandibularer Funktionsstorungen in der Praxis
The potential for two overlapping fragments of DNA from a clone of newly isolated alkanes degradi... more The potential for two overlapping fragments of DNA from a clone of newly isolated alkanes degrading bacterium Pseudomonas frederiksbergensis encoding sequences with similar homology to two parts of functional proteins is described. One strand contains a sequence with high homology to alkanes monooxygenase (alkB), a member of the alkanes hydroxylase family, and the other strand contains a sequence with some homology to alcohol dehydrogenase gene (alkJ). Overlapping of the genes on opposite strands has been reported in eukaryotic species, and is now reported in a bacterial species. The sequence comparisons and ORFS results revealed that the regulation and the genes organization involved in alkane oxidation represented in Pseudomonas frederiksberghensis varies among the different known alkane degrading bacteria. The alk gene cluster containing homologues to the known alkane monooxygenase (alkB), and rubredoxin (alkG) are oriented in the same direction, whereas alcohol dehydrogenase (al...
RNA Interference Suppression of v-ATPase B and Juvenile Hormone Binding Protein Genes Through Topically Applied dsRNA on Tomato Leaves: Developing Biopesticides to Control the South American Pinworm, Tuta absoluta (Lepidoptera: Gelechiidae)
Frontiers in Physiology, 2021
The South American pinworm Tuta absoluta (Meyrick) (Family: Gelechiidae) is one of the most devas... more The South American pinworm Tuta absoluta (Meyrick) (Family: Gelechiidae) is one of the most devastating lepidopteran pests in the developing countries of South America, Africa, and Asia. This pest is classified as the most serious threat for tomato production worldwide. In the present study, we analyzed RNAi-mediated control through exogenously applied dsRNA delivery on tomato. The dsRNA treatments were made to target the juvenile hormone binding protein and the v-ATPase B. Both mRNA targets were cloned, validated by sequencing, and used to produce each dsRNA. After treatments the relative transcript expression was analyzed using qRTPCR to assess to efficacy of RNAi. A leaf-dip assay was used to provide late 2nd instar larvae three feeding access periods: 24, 48, and 72 h, to evaluate the effect of gene silencing of each target. Larvae were fed tomato leaves coated with five different RNAi concentrations (10, 20, 30, 40, and 50 micrograms/centimeter-squared), that suppressed two gen...
Alexandria Science Exchange Journal, 2018
Water is the most basic element for the life on earth. Reliable access to cleanly and affordable ... more Water is the most basic element for the life on earth. Reliable access to cleanly and affordable water is considered main challenge for the total world. Along with waste water progress, environmental pollutants like toxic heavy metals are widely spreading throughout the world. The presence of heavy metal in aqueous environment poses a dangerous environmental risk.The utilization of heavy metal resistance bacteria might avail a cost-efficient tool for bioremediations of contaminated water bodies. During our screening program for heavy metal resistant bacteria isolated from agriculture wastewater sample collected from mainsheet El Awqaf near kafr el-Dewar), EL-Bahaira Egypt was able to grow on (LB) medium supplemented with Cadmium (50 to 500 mg/l),six isolates were chosen (4(DB-3), 5(DB-3), 6CB-3), 7(CB-7), J (CB-5), and M (CB-3) based on the metal tolerance concentration (MIC) values these isolates were gram negative rod shaped bacteria.
Molecules, 2021
Spodoptera litura Fab. is a polyphagous pest causing damage to many agriculture crops leading to ... more Spodoptera litura Fab. is a polyphagous pest causing damage to many agriculture crops leading to yield loss. Recurrent usage of synthetic pesticides to control this pest has resulted in resistance development. Plant-derived diterpenoid compound andrographolide was isolated from the leaves of Andrographis paniculata. It was analysed by gas chromatography-mass spectroscopy and quantified by HPLC. Nutritional indices and digestive enzymatic profile were evaluated. Third, fourth and fifth instar larvae were treated with different concentrations of andrographolide. At 3, 6 and 9 ppm-treated concentrations the larvae showed decreased RGR, RCR, ECI, ECD values with adverse increase in AD. The digestive enzymes were significantly inhibited when compared with control. Conspicuously, andrographolide showed pronounced mortality of S. litura by inhibition of enzyme secretion and intake of food. The binding ability of andrographolide with CYTP450 showed high affinity with low binding energy. And...
Volatile toxin of Limonia acidissima (L.) produced larvicidal, developmental, repellent, and adulticidal toxicity effects on Aedes aegypti (L.)
Toxin Reviews, 2020
This study aimed to evaluate the nematicidal activity of two marine algae (Colpomenia sinuosa and... more This study aimed to evaluate the nematicidal activity of two marine algae (Colpomenia sinuosa and Corallina mediterranea) extracts and their synthesized silver nanoparticles against the root-knot nematode (Meloidogyne incognita) infecting tomato plant. Scanning Electron Microscope (SEM) showed that the obtained nanoparticles were aggregated in anisotropic Ag particles. Transmission Electron Microscope (TEM), results showed the particles size was less than 40 nm. Whenever, FT-IR analysis spectrum presented sharp absorbance between 440 and 4000 cm-1 for the obtained nanoparticles, with 13 distinct peaks ranged from 3915 − 474.Both of methylene chloride extract and its synthesized green silver nanoparticles were applied against the M. incognita. The results indicated that the synthesized silver nanoparticles of C. sinuosa exhibited the highest nematicidal activity. Besides, they reduced number of nematode galls, number of egg-masses per root and eggs/egg mass, as well as growth paramet...
Plants-derived bioactives: Novel utilization as antimicrobial, antioxidant and phytoreducing agents for the biosynthesis of metallic nanoparticles
Microbial Pathogenesis, 2021
Medicinal and aromatic higher plants are sustainable resources for natural product compounds, inc... more Medicinal and aromatic higher plants are sustainable resources for natural product compounds, including essential oils, phenolics, flavonoids, alkaloids, glycosides, and saponins. Extractives and essential oils as well as their bioactive compounds have many uses due to their antimicrobial, anticancer, and antioxidant properties as well as application in food preservation. These natural compounds have been reported in many works, for instance biofungicide with phenolic and flavonoid compounds being effective against mold that causes discoloration of wood. Additionally, the natural extracts from higher plants can be used to mediate the synthesis of nanoparticle materials. Therefore, in this review, we aim to promote and declare the use of natural products as environmentally eco-friendly bio-agents against certain pathogenic microbes and make recommendations to overcome the extensive uses of conventional pesticides and other preservatives.
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Papers by Ahmed Abdel-Megeed