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61.
Souad El Hafidi Khadija Bakhy Mohammed Ouhssine Abderrahim Benzakour Hamid Khamar Joseph Casanova Mathieu Paoli Félix Tomi 《化学与生物多样性》2023,20(1):e202201022
Cladanthus scariosus (Ball) Oberpr. & Vogt is endemic to Moroccan High Atlas. It is known under the vernacular names Irezghi or Irezgui. Three essential oil samples have been isolated from aerial parts and analyzed by combination of chromatographic and spectroscopic techniques [gas chromatography (GC) in combination with retention indices (RI), gas chromatography-mass spectrometry (GC/MS) and 13C-NMR spectroscopy]. The compositions of oil samples were dominated by monoterpenes: α-pinene sabinene, and terpinen-4-ol. Chamazulene and dihydrochamazulene isomers as well as various hemiterpene esters and analogs have been identified. To evidence a chemical variability, statistical analysis performed on 13 oil sample compositions allowed partitioning into three groups, mainly differentiated by their contents of sabinene, camphor, borneol, terpinen-4-ol, and germacrene D. 相似文献
62.
Samet Evyapan Emine Elçin Oruç-Emre Yusuf Sıcak Ayşegül Karaküçük-İyidoğan Gizem Tatar Yılmaz Mehmet Öztürk 《化学与生物多样性》2023,20(8):e202300626
In this study, new chiral thiourea and 1,3-thiazolidine-4,5-dione derivatives were synthesized, it was aimed to evaluate the various biological activities and molecular docking of these compounds. Firstly, the new thioureas ( 1 – 16 ) were obtained by reacting 1-naphthylisothiocyanate with different chiral amines. Then, the chiral thioureas were cyclized with oxalyl chloride to obtain 1,3-thiazolidine-4,5-dione derivatives ( 17 – 32 ). All compounds were evaluated with several in vitro antioxidant and enzyme inhibition activities. Compound 30 was the most active compound against AChE, with a value of IC50=8.09±0.58 μM. On the other hand, all compounds were tested in silico absorption, distribution, metabolism, and excretion (ADME) assays to better understand their bioavailability. These physicochemical properties, pharmacokinetics, and drug-likeness of all compounds were calculated using SwissADME. Furthermore, according to molecular docking analyses compound 30 exhibited significant binding affinities for all enzymes. Based on our overall observations, compound 30 could be recommended as a potential lead for the therapuetic of Alzheimer's. 相似文献
63.
Amir Hamza Khan Dr. Said Hassan Muhammad Aamir Dr. Muhammad Waseem Khan Dr. Fazal Haq Junaid Hayat Dr. Muhammad Rizwan Dr. Amin Ullah Izzat Ullah Dr. Gokhan Zengin Dr. Arshad Farid 《化学与生物多样性》2023,20(10):e202301068
The current study was designed to evaluate the antioxidant, anticancer and antimicrobial activities of silver nanoparticles (AgNPs) biosynthesized by Spirulina platensis extract. The biosynthesized silver nanoparticles were characterized using Fourier transform infrared (FT-IR) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) analysis. The antioxidant activity of the biosynthesized AgNPs were determined via DPPH radical scavenging assay while its anticancer activity was determined using the MTT assay. The antimicrobial activity of the biosynthesized AgNPs were analyzed by disc diffusion method. Spirulina platensis acts as a reducing and capping agent. The efficacy of silver nanoparticles (AgNPs) in inhibiting the growth of Gram-negative bacteria, specifically Acetobacter, Klebsiella, Proteus vulgaris, and Pseudomonas aeruginosa, was assessed by the utilisation of the diffusion method. The study aimed to evaluate the efficacy of biosynthesized silver nanoparticles (AgNPs) against many strains of Pseudomonas aeruginosa bacteria. The findings of the study revealed that when administered in doses of 50 μl, 75 μl, and 100 μl, the largest observed zone of inhibition corresponded to measurements of 10.5 mm, 14 mm, and 16 mm, respectively. A zone of inhibition with dimensions of 8 mm, 10.5 mm, and 12 mm was detected during testing against Acetobacter at concentrations of 50 μl, 75 μl, and 100 μl, respectively. The findings also indicate that there is a positive correlation between the concentration of AgNP and the DPPH scavenging ability of silver nanoparticles. The percentage of inhibition observed at concentrations of 500 μg/ml, 400 μg/ml, 300 μg/ml, 200 μg/ml, and 100 μg/ml were recorded as 80±1.98, 61±1.98, 52±1.5, 42±1.99, and 36±1.97, respectively. In addition, it was observed that the silver nanoparticles exhibited the greatest antioxidant activity at a concentration of 500 g/ml, with a measured value of 80.89±1.99. The IC-50 values, representing the inhibitory concentration required to achieve 50 % inhibition, were found to be 8.16, 19.15, 30.14, 41.13, and 63.11 at inhibition levels of 36±1.97, 42±1.99, 52±1.5, 61±1.98, and 80±1.98, respectively. 相似文献
64.
Ayoub Kdimy Dr. Seong Jong Kim Dr. Zulfiqar Ali Dr. Md Imdadul H. Khan Dr. Siddharth K. Tripathi Prof. Souad El Hajjaji Prof. Hoang V. Le 《化学与生物多样性》2023,20(9):e202300903
Many plants have been known to be contaminated and accumulate plasticizers from the environment, including water sources, soil, and atmosphere. Plasticizers are used to confer elasticity and flexibility to various fiber and plastic products. Consumption of plasticizers can lead to many adverse effects on human health, including reproductive and developmental toxicity, endocrine disruption, and cancer. Herein, we report for the first time that two plasticizers, bis(2-ethylhexyl) terephthalate (DEHT) and bis(2-ethylhexyl) phthalate (DEHP), have been isolated from the leaves of Capparis spinosa L. (the caper bush), a plant that is widely used in food seasonings and traditional medicine. 297 mg/kg of DEHT and 48 mg/kg of DEHP were isolated from dried and grounded C. spinosa L. leaves using column chromatography and semi-preparative high-performance liquid chromatography. Our study adds to the increase in the detection of plasticizers in our food and medicinal plants and to the alarming concern about their potential adverse effects on human health. 相似文献
65.
Sarrah M'Barek Ziad Fajloun Sandrine Cestle Christiane Devaux Pascal Mansuelle Amor Mosbah Besma Jouirou Massimo Mantegazza Jurphaas van Rietschoten Mohamed El Ayeb Herv Rochat Jean‐Marc Sabatier Francois Sampieri 《Journal of peptide science》2004,10(11):666-677
Aah I is a 63-residue alpha-toxin isolated from the venom of the Buthidae scorpion Androctonus australis hector, which is considered to be the most dangerous species. We report here the first chemical synthesis of Aah I by the solid-phase method, using a Fmoc strategy. The synthetic toxin I (sAah I) was renatured in DMSO-Tris buffer, purified and subjected to thorough analysis and comparison with the natural toxin. The sAah I showed physico-chemical (CD spectrum, molecular mass, HPLC elution), biochemical (amino-acid composition, sequence), immunochemical and pharmacological properties similar to those of the natural toxin. The synthetic toxin was recognized by a conformation-dependent monoclonal anti-Aah I antibody, with an IC50 value close to that for the natural toxin. Following intracerebroventricular injection, the synthetic and the natural toxins were similarly lethal to mice. In voltage-clamp experiments, Na(v) 1.2 sodium channel inactivation was inhibited by the application of sAah I or of the natural toxin in a similar way. This work describes a simple protocol for the chemical synthesis of a scorpion alpha-toxin, making it possible to produce structural analogues in time. 相似文献
66.
Developmental and reproductive rates ofAdonia variegataGoeze,Coccinella novemnotataHerbst,C. septempunctataL., andC. undecimpunctataL. were studied in wheat and barley in Central Saudi Arabia. Beetles were reared in the laboratory at 25 ± 2°C onBrevicoryne brassicae(L.) andRhopalosiphum padiL.A. variegataandC. undecimpunctatahad significantly higher egg hatching (X = 81.8 and 74.5%), adult longevity (X = 71.8 and 70.0 days), and survival (X = 61.8 and 61.5%), respectively.Coccinella undecimpunctatahad the highest fecundity (X = 370.5 eggs/female) and longest oviposition period (X = 29.8 days).C. septempunctataexhibited the lowest values for these biological parameters. No differences were evident in the total developmental time or egg and pupal duration, although species differences occurred in the larval duration. Larvae ofA. variegatadeveloped faster (X = 11.8 days) than Larvae ofC. septempunctata(X = 12.0 days),C. undecimpunctata(X = 12.2 days), orC. novemnotata(X = 13.1 days). The intrinsic rate of increase (rm) and predicted population density were higher forC. undecimpunctata(X = 0.093 and 98553) after 60 days than forC. novemnotata(X = 0.088 and 59405),C. septempunctata(X = 0.086 and 35033), orA. variegata(X = 0.082 and 37991), respectively. 相似文献
67.
Immunocytochemical identification and localization of lipase in cells of the mycelium of Penicillium cyclopium variety 总被引:1,自引:0,他引:1
The localization of lipase in cells of the fungus Penicillium cyclopium was investigated. It was shown by differential centrifugation of a homogenate of mycelial cells that the activity of the enzyme is associated with the cell wall. A study of ultrathin sections of mycelium fixed using the method of Zvyagintseva in an electron microscope showed that the final products of lipolytic activity of the enzyme is localized on the cell wall. Antibodies were raised against the purified A and B lipases from P. cyclopium and their specificity was assessed by enzyme-linked immunosorbent assay. The antibody preparation was used in cytochemical investigation by immunogold labelling. This study permits the localization of cell-bound lipase mainly in the cell wall and in the periplasmic space. The identity of the cell-bound lipase with one of the two extracellular lipases is also demonstrated. 相似文献
68.
Mona El Agoze Marylène Poirié Georges Périquet 《Entomologia Experimentalis et Applicata》1995,75(3):251-255
In most insect species where double matings occur, sperm from the second male preferentially fertilize subsequent eggs. However,
we demonstrate here that, as already shown for some other hymenopteran species, this is not the case in the ichneumonid waspDiadromus pulchellus (Wesmeal): sperm from the first male usually father all the female progeny. This precedence of the first male sperm is also
observed in double matings involving an haploid male and a diploid sterile male, whichever is the first mating male. We discuss
the consequences of this phenomenon from an evolutionary point of view. 相似文献
69.
70.
To determine some physiological parameters implicated in somatic embryogenesis in date palm (Phoenix dactylifera L.), peroxidases have been studied. Activated charcoal commonly used in date palm tissue culture as an essential antibrowning factor decreased cellular protein contents and peroxidase activities. During the first months of culture, the conventionally used medium (100 mg dm?3 of 2,4-dichlorophenoxyacetic acid, 3 g dm?3 charcoal) reduces 2 to 3 and 4 to 6 times protein contents and peroxidase activities, respectively, in comparison with the same one containing only 5 mg dm?3 of 2,4-D and with or without 150 mg dm?3 charcoal. In addition, the standard procedure decreased the embryogenic potential which is positively related to the intra- and extracellular (excreted into culture medium) peroxidase activities. In medium with embryogenic calli, extracellular peroxidase activity was three times as high as the activity determined in the same medium with non-embryogenic calli. There were two basic isoforms and four to five acidic bands characterizing the embryogenic calli. It can be suggested that peroxidases play a key role in somatic embryogenesis of date palm and the charcoal used at 3 g dm?3 constitute a perturbating factor for this process. 相似文献