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Isolation, distribution and evaluation of cytotoxic and antioxidant activity of cultivable actinobacteria from the Oman Sea sediments

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Acta Oceanologica Sinica 2019年第12期38卷 84-90页

作者： Mohsen Gozari Nima Bahador Amir Reza Jassbi Mohammad Seddiq Mortazavi samad Hamzehei Ebrahim Eftekhar Department of Microbiology College of ScienceAgriculture and Modern TechnologyShiraz BranchIslamic Azad UniversityShiraz 71331Iran Persian Gulf and Oman Sea Ecological Research Center Iranian Fisheries Science Research Institute(IFSRI)Agricultural ResearchEducation and Extension Organization(AREEO)Bandar Abbas 79131Iran Medicinal and Natural Products Chemistry Research Center Shiraz University of Medical SciencesShiraz 71331Iran Iranian National Institute of Oceanography and Atmospheric Science Tehran 1414Iran Molecular Medicine Research Center Hormozgan Health InstituteHormozgan University of Medical SciencesBandar Abbas 79131Iran

Screening bioactive natural products from bacteria is a determinative step in the drug discovery programs. The present study aim to isolate actinobacteria from the Oman Sea sediments for determining the effects of different culture media and treatments on the yield of the isolation process, and measure the DPPH radical scavenging and Artemia cytotoxic activity of culture extracts of the actinobacterial isolates. A total of 290 actinobacterial isolates were collected from 14 sediment samples. Heat treatment(40.68%) and M4 medium(29.31%) exhibited the maximum isolation rates of actinobacteria. Streptomyces isolates were dominantly distributed in all of the investigated stations according to 16 S rRNA gene sequencing. The distribution pattern of Streptomyces followed a depth-dependent frequency trend, whereas the members of rare genera including Micromonospora, Nocardia Actinoplanes, Nocardiopsis, Saccharopolyspora and Crossiella were distributed in deeper stations. Approximately,25% of the examined isolates could scavenge 90% of 10^–4 mol/l DPPH solutions at 1 250 μg/ml final concentration of their ethyl acetate culture extracts. Furthermore, the most potent extracts could scavenge DPPH radicals with IC50 ranges from 356.8 to 566.4 μg/ml. Brine shrimp cytotoxicity tests showed that 38.88% of the examined culture extracts exhibited lC50 lower than 1 000 μg/ml against the Artemia cells. Moreover, the most potent culture extracts exhibited lC50 range from 335.4 to 534.4 μg/ml. Phylogenetic analysis by 16 S rRNA gene sequence revealed that the OS 005, OS 263 and OS 157 closely related to Streptomyces djakartensis, Streptomyces olivaceus and Nocardiopsis dassonvillei respectively. These results suggested the widespread distribution of the antioxidant and cytotoxic producing actinobacteria in the Oman Sea sediments, which could be considered as promising candidates for the discovery of microbial bioactive compounds.

关键词： antioxidant activity cytotoxic activity marine actinobacteria Oman Sea phylogenetic analysis

Existence of Approximate Solutions to Nonlinear lorenz System under Caputo-Fabrizio Derivative

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Computer Modeling in Engineering & Sciences 2023年第5期135卷 1669-1684页

作者： Khursheed J.ansari Mustafa Inc K.H.Mahmoud Eiman Department of Mathematics College of ScienceKing Khalid UniversityAbha61413Saudi Arabia Department of Computer Engineering Biruni UniversityIstanbul34010Turkey Department of Mathematics Science FacultyFirat UniversityElazig23119Turkey Department of Medical Research China Medical UniversityTaichung40402Taiwan Department of Physics College of Khurma University CollegeTaif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of Mathematics University of MalakandChakdara Dir(L)Khyber Pakhtunkhwa18000Pakistan

In this article,we developed sufficient conditions for the existence and uniqueness of an approximate solution to a nonlinear system of lorenz equations under Caputo-Fabrizio fractional order derivative(CFFD).The required results about the existence and uniqueness of a solution are derived via the fixed point approach due to Banach and ***,we enriched our work by establishing a stable result based on the Ulam-Hyers(U-H)***,the approximate solution is computed by using a hybrid method due to the laplace transform and the Adomian decomposition *** computed a few terms of the required solution through the mentioned method and presented some graphical presentation of the considered problem corresponding to various fractional *** results of the existence and uniqueness tests for the lorenz system under CFFD have not been studied ***,the suggested method results for the proposed system under the mentioned derivative are ***,the adopted technique has some useful features,such as the lack of prior discrimination required by wavelet *** proposed method does not depend on auxiliary parameters like the homotopy method,which controls the *** proposed method is rapidly convergent and,in most cases,it has been used as a powerful technique to compute approximate solutions for various nonlinear problems.

关键词： lorenz system CFFD fixed point approach approximate solution

Interactive Effects of Drought Stress and Phytohormones or Polyamines on Growth and Yield of Two M(<i>Zea maize</i>l) Genotypes

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American Journal of Plant Sciences 2011年第6期2卷 790-807页

作者： M. A. K. Shaddad M. Hamdia abd El-samad H. T. Mohammed 不详

Two maize genotypes (Nefertiti and Bashaier) were picked up from nine maize genotypes during the early vegetative growth (25 days) to be cultivated in open field upon the crop yield under the different drought stress levels (90,70,50,30) or under the interaction effect of drought stress and phytohormones or polyamines. According to the data of growth criteria, the maize genotype Nefertiti was found to be the most drought sensitive genotype, while the genotype Bashaier was found to be the most drought resistant genotype. Additionally while the photosynthetic pigments remained more or less unchanged in genotype Bashaier, their biosynthesis destroyed earlier in the drought sensitive genotype (Nefertiti). Also while the genotype Bashaier absorbed and accumulated a sufficient amount of mono and divalent cations (K+, Ca++ and Mg++), the genotype Nefertiti did not. Accordingly while the genotype Bashaier gave a crop yield up to 50% field capacity, the genotype Nefertiti gave a crop yield only up to 70% field capacity and failed to give a crop yield beyond this level. The interaction effect of drought stress and phytohormones and polyamines improved the all above characteristics. Interestingly each of these activators considerably improved the production of crop yield only in genotype Bashaier specially polyamines they produced more than 60% field capacity and at the level of 30% field capacity (the level which did not give crop yield in this genotype). However, phytohormones in generally did not make an important effect on the crop yield in genotype Nefertiti although they improved the dry matter production during the vegetative stages. Such situation seemed to be complicated and borne many questions to be studied in the future.

关键词： Drought Maize (Zea maize l.) Phytohormones Polyamines leaf Area Dry Weight Yield

Transpressive Structures in the Ghadir Shear Belt, Eastern Desert, Egypt: Evidence for Partitioning of Oblique Convergence in the Arabian-Nubian Shield during Gondwana Agglutination

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Acta Geologica Sinica(English Edition) 2019年第6期93卷 1614-1646页

作者： Mohamed abd El-WAHED Samir KAMH Mahmoud ASHMAWY Aly SHEBl Geology Department Faculty of Science Tanta University

Transpressional deformation has played an important role in the late Neoproterozoic evolution of the ArabianNubian Shield including the Central Eastern Desert of *** Ghadir Shear Belt is a 35 km-long,NW-oriented brittleductile shear zone that underwent overall sinistral transpression during the late *** this shear belt,strain is highly partitioned into shortening,oblique,extensional and strike-slip structures at multiple ***,strain partitioning is heterogeneous along-strike giving rise to three distinct structural *** the East Ghadir and Ambaut shear belts,the strain is pure-shear dominated whereas the narrow sectors parallel to the shear walls in the West Ghadir Shear Zone are simple-shear *** domains are comparable to splay-dominated and thrust-dominated strike-slip shear *** kinematic transition along the Ghadir shear belt is consistent with separate strike-slip and thrustsense shear *** earlier fabric(S1),is locally recognized in low strain areas and SW-ward thrusts.S2 is associated with a shallowly plunging stretching lineation(l2),and defines^NW-SE major upright macroscopic folds in the East Ghadir shear belt.F2 folds are superimposed by^NNW–SSE tight-minor and major F3 folds that are kinematically compatible with sinistral transpressional deformation along the West Ghadir Shear Zone and may represent strain partitioning during deformation.F2 and F3 folds are superimposed by ENE–WSW gentle F4 folds in the Ambaut shear *** sub-parallelism of F3 and F4 fold axes with the shear zones may have resulted from strain partitioning associated with simple shear deformation along narrow mylonite zones and pure shear-dominant deformation in fold *** ENEstriking shear zones were subsequently active at ca.595 Ma,coeval with sinistral shearing along NW-to NNW-striking shear *** occurrence of upright folds and folds with vertical axes suggests that transpression plays a significant role in

关键词： Arabian-Nubian Shield Ghadir shear belt transpression splay-dominated and thrust-dominated strike-slip shear zones Egypt

Dissolved gas analysis and dissipation factor measurement of mineral oil-based nanofluids under thermal and electrical faults

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High Voltage 2023年第3期8卷 455-465页

作者： Ahmed Maher Diaa-Eldin A.Mansour Khaled Helal Ramadan A.A.abd El Aal Department of Electrical Engineering Faculty of EngineeringPort-Said UniversityPort-SaidEgypt Department of Electrical Power Engineering Faculty of EngineeringEgypt-Japan University of Science and Technology(E-JUST)New Borg El-Arab CityAlexandriaEgypt Department of Electrical Power and Machines Engineering Faculty of EngineeringTanta UniversityTantaEgypt

Mineral oil is the most frequent insulating liquid used in oil-immersed transformers for electrical insulation and heat ***,oil-based nanofluids are becoming more popular in scientific research as they have proved to have better dielectric and thermal *** applying these nanofluids into actual transformers,they would be exposed to thermal and electrical ***,The aim of the authors is to investigate the generation pattern of dissolved gases in nanofluids under thermal and electrical faults and to assess the applicability of traditional Dissolved Gas Analysis(DGA)techniques if oil-based nanofluids are used in ***-based nanofluid samples were prepared using a magnetic stirrer and an ultrasonic homogeniser and then subjected to simulated thermal and electrical faults in the laboratory using properly sealed test *** types of metal oxides,Silicon dioxide,Titanium dioxide,and Aluminium oxide nanoparticles,have been used to prepare nanofluids with 0.02 g/l and 0.04 g/l *** gases released and dissolved into oil due to the simulated faults were analysed and compared to traditional mineral oil as a *** dielectric dissipation factor was obtained and analysed for all *** to the findings,the presence and concentration of nanoparticles were shown to influence the amount of gases *** a result,this research is crucial in guaranteeing that traditional DGA techniques can be employed in transformers that use oil-based nanofluids.

关键词： electrical thermal dioxide

Demography of the threatened endemic shrub, Arbutus pavarii,in the Al-Akhdar mountainous landscape of libya

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Journal of Forestry Research 2016年第6期27卷 1295-1303页

作者： Hanan F.Kabiel Ahmad K.Hegazy lesley lovett-Doust Saud l.Al-Rowaily abd EI-Nasser El Borki Department of Botany and Microbiology Faculty of ScienceCairo University Giza 12613 Egypt Department of Biology and Chemistry Nipissing UniversityNorth Bay ON Canada Department of Plant Production College of Food and Agricultural Sciences King Saud University Riyadh SaudiArabia Department of Botany Faculty of Science University of Benghazi Benghazi Libya

We sampled twenty populations of the vulnera- ble endemic shrub or tree, Arbutus pavarii Pampan., at different elevations and aspects within the A1-Akhdar mountainous region of libya. Our sampling sites were at elevations ranging from 285 to 738 m above sea level, and several different habitats： vallies （locally known as wadis）, north- and south-facing slopes, and mountaintops. All individuals within each quadrat were studied. Population size and structure, and plant functional traits were assessed. None of the populations had a stable distribution of size classes. Some consisted mostly of small plants, with little or no fruit production; others consisted only of mid-sized and large plants, with high fruit production, but no juvenile recruitment. There was a significant increase in percent cover with increasing elevation; reproductive output （the number of fruits per branch and total number of fruits per individual） also generally increased with elevation. In some of these populations the lack of recruitment, and in others the failure to produce fruit, together constituted serious demographic threats. In light of these results, recommen- dations are made for conservation of this vulnerable endemic species.

关键词： Al-Akhdar mountains Conservation Demography Elevation Functional traits Vulnerable species

Assessment of Kl-6 as a tumor marker in patients with hepatocellular carcinoma

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World Journal of Gastroenterology 2005年第42期11卷 6607-6612页

作者： Amal Gad Eiji Tanaka Akihiro Matsumoto Moushira abd-el Wahab abd el-Hamid Serwah Fawzy Attia Khalil Ali Howayda Hassouba abd el-Raoof el-Deeb Tetsuya Ichijyo Takeji Umemura Hidetomo Muto Kaname Yoshizawa Kendo Kiyosawa Second Department of Internal Medicine Shinshu University School of Medicine Matsumoto Japan Howayda Hassouba Abd el-Raoof el-Deeb Suez Canal University School of Medicine Ismailia Egypt Second Department of Internal Medicine Shinshu University School of Medicine Matsumoto Japan Howayda Hassouba abd el-Raoof el-Deeb Suez Canal University School of Medicine Ismailia Egypt Shinshu University Graduate School of Medicine Institutes of Organ Transplants Reconstructive Medicine and Tissue Engineering Matsumoto Japan

AIM： To investigate the clinical significance of Kl-6 as a tumor marker of HCC in two different ethnic groups with chronic liver disease consecutively encountered at outpatient clinics. METHODS： Serum Kl-6 was measured by the sandwich enzyme immunoassay method using the Kl-6 antibody （Ab） as both the capture and tracer Ab according to the manufacturer＇s instructions （Eisai, Tokyo, Japan）. Assessment of alpha fetoprotein （AFP） and protein induced vitamin K deficiency or absence （PIVKA-II） was performed in both groups using commercially available kits. RESUlTS： A significantly higher mean serum Kl-6 （556±467 U/l） was found in HCC in comparison with non-HCC groups either with （391±176 U/l; P〈0.001） or without （361±161 U/l; P〈0.001） liver cirrhosis （lC）. Serum Kl-6 level did not correlate with either AFP or PIVKA-II serU/levels. Using rec：eiver operating curve analysis for Kl-6 as a predictor for HCC showed that the area under the curve was 0.574 （95%CI = 0.50-0.64） and the Kl-6 level that gave the best sensitivity （61%） was found to be 334 U/l but according to the manufacturer＇s instructions; a cut-off point of 500 U/l was used that showed the highest specificity （80%） in comparison with AFP and PIVKA-II （78% vs 72% respectively）. Combining the values of the three markersimproved specificity of AFP for HCC diagnosis from 78% for AFP alone; 93% for AFP plus PIVKA-II to 99% for both plus Kl-6 value （P〈0.001）. Mean serum alkaline phosphatase level was significantly higher in Kl-6 positive （564＋475） in comparison with Kl-6 negative （505＋469） HCC patients （P = 0.021）, but such a difference was not found among non-HCC corresponding groups. CONClUSION： Kl-6 is suggested as a tumor for HCC. Its positivity may reflect HCC-associated cholestasis and/ or local tumor invasion.

关键词： Tumor markers liver disease Hepatocellularcarcinoma

lanthanide amino acid Schiff base complexes:synthesis,spectroscopic characterization,physical properties and in vitro antimicrobial studies

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Journal of Rare Earths 2013年第7期31卷 715-721页

作者： Samir Alghool M.Sh.Zoromba Hanan F.abd El-Halim Department of Chemistry Faculty of SciencePort Said UniversityPort Said 42521Egypt Department of Chemistry Faculty of PharmacyMisr International UniversityIsmailia RoadKm 28 CairoEgypt

Complexes of la （III）, Nd（III）, Gd（III）, Sm（III）, and Ce（IV） were synthesized with Schiff base [（3,5-di-tert-butyl-2-hy- droxybenzyl） amino] acetic acid （H3l）. The ligand and its complexes were synthesized and characterized based on the following analysis： elemental analyses, FAB-mass, molar conductance measurements, magnetic measurement, UV-visible, IR, and NMR spectral studies. The spectral data revealed that the ligand acted as a neutral tridentate coordinating to metal ion through ONO donor sequence. Thermal degradation studies of the ligand and its complexes showed that the previous lanthanide complexes were more thermally stable than the ligand itself. The Schiff base and its complexes were screened for their antibacterial （Escherichia coli, Staphylococcus aureus） and antifungal （Aspergillus flavus and Candida Albicans）.

关键词： lanthanide Schiffbase complexes physical properties biological activity rare earths

Synthesis of an eco-friendly nanocomposite fertilizer for common bean based on carbon nanoparticles from agricultural waste biochar

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Pedosphere 2021年第6期31卷 923-933页

作者： Dina M.SAlAMA Mahmoud E.abd El-AZIZ Mehrez E.El-NAGGAR Essam A.SHAABAN Mohamed S.abd El-WAHED Vegetable Research Department National Research Centre33 El Bohouth StreetDokkiGiza 12622(Egypt) Polymers&Pigments Department National Research Centre33 El Bohouth StreetDokkiGiza 12622(Egypt) Textile Research Division National Research Centre33 El Bohouth StreetDokkiGiza 12622(Egypt) Pomology Department National Research Centre33 El Bohouth StreetDokkiGiza 12622(Egypt) Botany Department National Research Centre33 El Bohouth StreetDokkiGiza 12622(Egypt)

The burning of agricultural waste is a major cause of environmental *** this study,we sought to prepare biochar from agricultural waste as a source material for the preparation of carbon nanoparticles(CNPs).Surface morphology,hydrodynamic particle size,and purity and crystallinity of CNPs were extensively investigated using transmission electron microscopy(TEM),zeta sizing,and X-ray diffraction(XRD)spectroscopy,*** CNPs were subsequently immersed in a solution of potassium nitrate(KNO_(3))to prepare a CNPs/NK nanocomposite(CNPs loaded with nitrogen(N)and potassium(K))as a nanocomposite fertilizer for common bean(Phaseolus vulgaris l.).The CNPs/NK nanocomposite was sprayed as a foliar fertilizer at 0,10,20,30,and 40 mg l^(-1) on common bean plants 25 d after sowing on a farm in Shebin El-Kom,El-Monifia,*** growth,yield,and quality of common bean were investigated during two successive growing seasons(2017 and 2018).The highest seed yields of 2.04 and 2.01 t ha^(-1) and the highest values of growth parameters including plant height of 61.5 and 59.2 cm,number of leaves per plant of 35 and 35,number of flowers per plant of 83.3 and 82.7,and plant fresh weight of 148.7 and 152.8 g plant^(-1) were obtained when using the CNPs/NK nanocomposite at a concentration of 20 mg l^(-1) during the 2017 and 2018 growing seasons,respectively.

关键词： foliar fertilizer N and K-loaded nanosized carbon particles Phaseolus vulgaris l. plant growth yield