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Synthesis, Characterization and Biological Activities of Binuclear Metal Complexes of 2-Benzoylpyridine and Phenyl(Pyridin-2-yl) Methanediol Derived from 1-Phenyl-1-(Pyridin-2-yl)-N-(Pyrimidin-2-yl) Methanimine Dihydrate Schiff Base 认领
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作者 Francis A. Ngounoue Kamga Evans Ngandung Mainsah +1 位作者 Maurice Kuate Peter T. Ndifon 《无机化学期刊(英文)》 2021年第1期20-42,共23页
The Schiff base, 1-phenyl-1-(pyridin-2-yl)-N-(pyrimidin-2-yl)methanimine dihydrate (L<sub>1</sub>) has been synthesized by the condensation reaction between 2-aminopyrimidine and 2-benzoylpyridine and char... The Schiff base, 1-phenyl-1-(pyridin-2-yl)-N-(pyrimidin-2-yl)methanimine dihydrate (L<sub>1</sub>) has been synthesized by the condensation reaction between 2-aminopyrimidine and 2-benzoylpyridine and characterized using <sup>13</sup>C-NMR, <sup>1</sup>H-NMR, microanalysis, FT-IR, DEPT-135, HSQC, HMBC, COZY, NOESY. The reaction of 1-phenyl-1-(pyridin-2-yl)-N-(pyrimidin-2-yl)methanimine dihydrate (L<sub>1</sub>) with salts of V(IV), Co(II) and Cu(II), however, resulted in the hydrolysis of L<sub>1</sub> to give binuclear metal complexes of 2-benzoylpyridine (L<sub>2</sub>) and phenyl(pyridin-2-yl)methanediol (L<sub>3</sub>) which were characterized using UV-visible spectroscopy, and TGA. The single crystal x-ray structure determined for the Copper(II) complex revealed that we obtained a compound previously obtained using a different method of synthesis. The Schiff base ligand (L<sub>1</sub>) is soluble in methanol, ethanol, DMSO, acetone and DMF. Microanalysis and Spectroscopic studies indicated that binuclear metal complexes were obtained by the coordination of metal ion to 2-benzoylpyridine (L<sub>2</sub>) and phenyl(pyridin-2-yl)methanediol (L<sub>3</sub>) from the hydrolysis of L<sub>1</sub>. Spectroscopic and elemental analysis reveal the formation of square pyramidal complexes of Co(II) and Cu(II) and a square planar complex of V(IV). <i>In vitro</i> antibacterial and antifungal activity against three bacterial strains (<i>Escherichia coli, Klebsiella pneumoniae</i> and <i>Staphylococcus aureus</i>) and three fungal stains (<i>Candida albicans, Candida glabrata and Candida parapsilosis</i>) showed moderate biological activity. Antioxidant studies reveal that only the binuclear Co(II) and oxovanadium(II) complexes are potent to eliminate free radicals. 展开更多
关键词 Binuclear Complexes Schiff Base 2-Benzoylpyridine Crystal Structure Antimicrobial Activity Antioxidant Activity
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文章速递中药抗卵巢癌作用及机制研究新进展 认领
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作者 文敏 周欣 +1 位作者 赵超 龚小见 《天然产物研究与开发》 CAS CSCD 北大核心 2021年第3期521-533,共13页
卵巢癌是女性常见的生殖器官恶性肿瘤之一,严重威胁着女性的生殖健康。中药治疗卵巢癌具有多靶点、多途径、毒副作用小等特点,近年来已成为国内外学者的研究热点。本文系统总结了中药复方药、植物药(多糖、黄酮类、生物碱、酚类、萜类... 卵巢癌是女性常见的生殖器官恶性肿瘤之一,严重威胁着女性的生殖健康。中药治疗卵巢癌具有多靶点、多途径、毒副作用小等特点,近年来已成为国内外学者的研究热点。本文系统总结了中药复方药、植物药(多糖、黄酮类、生物碱、酚类、萜类、醌类、皂苷、酯类、挥发油、醚类)、动物药及矿物药抗卵巢癌的活性及作用机制,并初步分析了中药有效成分抗卵巢癌的构效关系,以期为抗卵巢癌药物的深入研究与应用提供参考。 展开更多
关键词 卵巢癌 中药 活性 作用机制 构效关系
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Preparation of Anatase Titanium Dioxide Nanoparticle Powders Submitting Reactive Oxygen Species (ROS) under Dark Conditions 认领
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作者 Thi Minh Phuong Nguyen Perrine Lemaitre +6 位作者 Masaki Kato Ken Hirota Kazuhiko Tsukagoshi Hirohisa Yamada Atsuki Terabe Hideto Mizutani Shingo Kanehira 《材料科学与应用期刊(英文)》 2021年第2期89-110,共22页
Recently, under the circumstances of pandemic of COVID-19 much attention has been paid to titanium dioxide TiO<sub>2</sub> as bactericidal agent;however, conventional TiO<sub>2</sub> requires u... Recently, under the circumstances of pandemic of COVID-19 much attention has been paid to titanium dioxide TiO<sub>2</sub> as bactericidal agent;however, conventional TiO<sub>2</sub> requires ultraviolet radiation or visible light to exercise its photocatalytic properties and its induced antimicrobial activity. In order to expand its applications directed at wide civil life, antibacterial TiO<sub>2</sub> being usable under dark conditions has been demanded. The present paper describes the powder characterization of newly developed potassium K and phosphorous P co-doped nanometer-size anatase TiO<sub>2</sub> powders using X-ray diffraction (XRD), scanning and transmission electron microscopies (SEM & TEM), Brunauer-Emmett-Teller method (BET), fourier-transform infrared spectroscopy (FT-IR), X-ray absorption fine structure (XAFS), electron spin resonance (ESR) and chemiluminescence (CL). It was found for the first time that thus prepared anatase TiO<sub>2</sub> could submit much reactive oxygen species (ROS) even in the dark, which has close relation with bactericidal activity in light interception. 展开更多
关键词 ANATASE Microbial Activity under Dark Conditions Potassium K Phosphorous P
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Antioxidant Activity Evaluation in a Series of Heterocyclic Compounds Derived from 1,8-Diaminonaphthalene 认领
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作者 Tuo Nanou Tiéba Kangah Niameke Jean Baptiste +4 位作者 Ballo Daouda Kablan Ahmont Landry Claude Kodjo Charles Guillaume Yapo Ossey Bernard Ziao Nahossé 《生物物理化学(英文)》 2021年第1期1-9,共9页
From (2,3-dihydro-1<i>H</i>-perimidin-2-yl)-phenyl, the substitution of OH group in <i>ortho</i> or <i>para</i> position on the phenyl ring, allows us to synthesize the studied comp... From (2,3-dihydro-1<i>H</i>-perimidin-2-yl)-phenyl, the substitution of OH group in <i>ortho</i> or <i>para</i> position on the phenyl ring, allows us to synthesize the studied compounds. These three compounds have been characterized by conventional spectroscopic methods (NMR and MS). The interest of this work is to review the antioxidant activity of our compounds. The antioxidant activity screening carried out according to FRAP and DPPH methods revealed significant anti-free radical properties for compounds 1 and 2 even at low concentrations. In contrast to the compound 2, compound 3 for which the OH group is substituted in <i>para</i> position has the lowest activity in both cases. Therefore the <i>para</i> position seems to be the least sensitive position to increase the antioxidant activity of this pharmacophore. 展开更多
关键词 PERIMIDINE Spectrometry Antioxidant Activity 2 2-Diphenyl-1-Picrylhydrazyl Method and Ferric Reducing Antioxidant Power Method
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Virucidal Activity of Chlorine Dioxide Gas for Reduction of Coronavirus on Surfaces and PPE 认领
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作者 Jeffrey Driver George Lukasik +2 位作者 Marie Bourgeois Patricia Tam Raymond Harbison 《职业病与环境医学(英文)》 2021年第1期13-19,共7页
A coronavirus (SARS-CoV-2) has caused a global pandemic and associated morbidity and mortality resultant from COVID-19. As a result of efforts to control direct (person to person) and indirect (contaminated objects, s... A coronavirus (SARS-CoV-2) has caused a global pandemic and associated morbidity and mortality resultant from COVID-19. As a result of efforts to control direct (person to person) and indirect (contaminated objects, surfaces, indoor air) transmission of the virus, various interventions have been evaluated. Studies were conducted to evaluate the efficacy of commercially available chlorine dioxide (CD) products to reduce viral loads on PPE (face masks) and surfaces using a novel dry gas release intervention. The efficacy of CD slow release 30-day sachets was tested on N95 face masks inoculated with human coronavirus OC43 in suspension. One sachet was placed with an inoculated mask in plastic resealable bags. Three trials were completed using the original sachet where a mask and sachet were placed into a plastic bag for 13 hours per sachet age of 1 day, 14 days, and 30 days. The amount of CD generated during a 13-hour treatment period was 0.30 mg. The nominal concentration of CD was estimated to be 317 mg/m<sup>3</sup>. All three tests demonstrated at least a 99.91% reduction of viral loading in the mask versus a non-treated control. Efficacy of CD dry gas fast releasing pods (Ultrashok) for fumigation was also tested in a 1344 ft<sup>3</sup> closed room. Two pods were placed in the space and CD surface virucidal efficacy was tested in three locations of the room after 1 hour and 2 hours of dwell time. The estimated nominal peak concentration was 15 ppmv in the room. The one-hour exposure saw a >99.91% OC43 reduction on surfaces and the two-hour exposure resulted in a >99.997% OC43 reduction on surfaces versus a non-treated control. These results indicate dry CD is highly effective against human coronavirus. CD was 99.91% effective for eliminating human coronavirus OC43 in both sachet and capsule fumigant form using both fast and slow release mechanisms. Rapid fumigant application is suitable for contaminated rooms, ambulances, emergency vehicles, and many types of PPE, most particularly porous PPE materials. The ga 展开更多
关键词 Chlorine Dioxide Gas CORONAVIRUS Virucidal Activity
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Assessment of Nutrient Composition and Antioxidant Activity of Some Popular Underutilized Edible Crops of Nagaland, India 认领
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作者 Chitta Ranjan Deb Neilazonuo Khruomo 《自然资源(英文)》 2021年第2期44-58,共15页
<span style="font-family:""><span style="font-family:Verdana;">In Nagaland ~70% of population lives in rural areas and depends on forest products for livelihood. Being part of the ... <span style="font-family:""><span style="font-family:Verdana;">In Nagaland ~70% of population lives in rural areas and depends on forest products for livelihood. Being part of the biodiversity hotspot, state is rich in biodiversity. The present study was an attempt made to understand the nutritional properties of 22 popular underutilized edible plants (UEP) Kohima, Phek, Tuensang districts. Results revealed moisture content of 22 studied plants ranged between 4.8 to 88.15 g/100g, while protein content varied be</span><span style="font-family:Verdana;">tween 0.00269</span></span><span style="font-family:Verdana;"> - </span><span style="font-family:""><span style="font-family:Verdana;">0.773 g/100g with highest in </span><i><span style="font-family:Verdana;">Terminalia chebula</span></i><span style="font-family:Verdana;"> (0.773</span></span><span style="font-family:""><span style="font-family:Verdana;"> g/100g) fruit while lowest protein content was in </span><i><span style="font-family:Verdana;">Setaria italica</span></i><span style="font-family:Verdana;"> (0.00269 g/100g). To</span><span style="font-family:Verdana;">tal carbohydrate content was between 0.198</span></span><span style="font-family:Verdana;"> - </span><span style="font-family:Verdana;">5.212 g/100g with highest in</span><span style="font-family:""> <i><span style="font-family:Verdana;">Setaria italica</span></i><span style="font-family:Verdana;"> (5.212 g/100g) and lowest in </span><i><span style="font-family:Verdana;">Juglans regia</span></i><span style="font-family:Verdana;"> (0.198 g/100g). Of </span><span><span style="font-family:Verdana;">the 22 samples, maximum antioxidant activity was in </span><i><span style="font-family:Verdana;">Terminalia chebula</span></i></span><span style="font-family:Verdana;"> fruits (37.49 μg/ml) followed by </span><i><span style="font-family:Verdana;">Clerodendrum glandulosum</span></i><span style="font-family:Verdana;"> (65.29 μg/ml) leaves, </span><i><span style="font-family:Verdana;">Phyllanthus emblica </spa 展开更多
关键词 Antioxidant Activity Food Security Nagaland NUTRIENT Rural Health Underutilized Edible Plants
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Synthesis and Insecticidal Evaluation of Novel Anthranilic Diamides Derivatives Containing 4-Chlorine Substituted N-Pyridylpyrazole 认领
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作者 Huangong Li Yangyang Zhao +6 位作者 Pengwei Sun Li Gao Yuxin Li Lixia Xiong Na Yang Sha Zhou Zhengming Li 《中国化学:英文版》 SCIE CAS 2021年第1期75-80,共6页
To search for potent insecticides targeting at ryanodine receptors(RyRs),a series of novel anthranilic diamides analogs containing 4-chlorine N-pyridylpyrazole were designed and synthesized.Their insecticidal activiti... To search for potent insecticides targeting at ryanodine receptors(RyRs),a series of novel anthranilic diamides analogs containing 4-chlorine N-pyridylpyrazole were designed and synthesized.Their insecticidal activities were evaluated and the preliminary struc ture-activity relationships(SARs)were discussed.The insecticidal results showed that some of the compounds(8a-8h,8m,8n)exhibited good larvicidal activities against oriental armyworm at 2.5 mg·L^(-1),and compound 8m possessed 60%insecticidal activityat 0.5 mg·L^(-1).For diamondback moth,8m exhibited better activity than Chlorantraniliprole at a hundred fold preference. 展开更多
关键词 Synthesis design Anthranilic diamides Insecticidal activity RyRs Structure-activity relationships
Anti-senescence and anti-wrinkle activities of 3-bromo-4,5-dihydroxybenzaldehyde from Polysiphonia morrowii Harvey in human dermal fibroblasts 认领
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作者 Su-Hyeon Cho Eun-Yi Ko +3 位作者 Soo-Jin Heo Seo-Young Kim Juhee Ahn Kil-Nam Kim 《亚太热带生物医学杂志:英文版》 SCIE CAS 2021年第2期74-80,共7页
Objective:To investigate the anti-senescence effect of 3-bromo-4,5-dihydroxybenzaldehyde(BDB)from Polysiphonia morrowii Harvey in human dermal fibroblasts(HDF).Methods:HDF were subjected to treatment of BDB and then t... Objective:To investigate the anti-senescence effect of 3-bromo-4,5-dihydroxybenzaldehyde(BDB)from Polysiphonia morrowii Harvey in human dermal fibroblasts(HDF).Methods:HDF were subjected to treatment of BDB and then treated with hydrogen peroxide(H2O2)to induce premature senescence.Senescence-associatedβ-galactosidase(SA-β-gal)activity in HDF was determined using the SA-β-gal staining method.Intracellular reactive oxygen species(ROS)production was measured using the 2’,7’-dichlorodihydrofluorescein diacetate assay.Western blotting assay was performed to assess the level of antioxidant enzyme glutathione peroxidase 1(GPX1).In addition,intracellular collagen and collagenase contents were analyzed using the respective ELISA kits.Elastase activity in HDF supernatants was measured from p-nitroaniline release and normalized using total protein content.Results:Treatment of HDF with H2O2 increased the activity of SA-β-gal,but BDB pre-treatment resulted in the reduction of SA-β-gal activity.Moreover,BDB significantly reduced H2O2-induced intracellular ROS production.BDB also markedly increased the level of GPX1,which was inhibited by 400μM of H2O2.Furthermore,in in vitro study,BDB significantly increased intracellular collagen content and decreased matrix metalloproteinase-1 and elastase activities in HDF.Conclusions:Our results demonstrate that BDB shows antisenescence and anti-wrinkle activities in vitro. 展开更多
关键词 Polysiphonia morrowii Harvey 3-bromo-4 5-dihydroxybenzaldehyde Oxidative stress Human dermal fibroblast Anti-senescence activity Anti-wrinkle activity
The Planet’s Response to Human Activity. Thermodynamic Approach 认领
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作者 Vladimir Kh. Dobruskin 《生态学期刊(英文)》 2021年第2期126-135,共10页
The applicability of the laws of thermodynamics to processes on Earth is discussed and it is shown that the chemical thermodynamics provides the reasonable basis for predicting probable changes. The historical evoluti... The applicability of the laws of thermodynamics to processes on Earth is discussed and it is shown that the chemical thermodynamics provides the reasonable basis for predicting probable changes. The historical evolution of the planet is considered in the framework of the Harari approach;a civilization’s level is estimated by the Kardashev scale based on the amount of energy it is able to use. During a short historical interval (≈500 years), when the effect of biological evolution is imperceptible and the main changes on the planet are caused by human activity, two systems are considered: 1) a nonequilibrium inhabited planet and 2) a quasi-equilibrium hypothetical planet without people, which is accepted as a comparison system. It is shown that in response to the energy impact, the equilibrium of the hypothetical system with the primordial nature is disturbed and processes are initiated aimed to prevent further growth of energy production. In the case of a real planet, this implements changes preventing the uncontrolled activities of humans—the energy producers. Climate change, an increase in the number of natural disasters and epidemics can be recognized as a direct response of the planet, while changes in socio-economic relations, morality, demographic situation, new threats etc. can be considered as an indirect reaction to changing conditions of human beings. The latter results from the mutual correlation between the progress of society, on the one hand, and humanitarian and political processes, on the other. The role of renewable and non-renewable energy sources in evolution is taken into account. Obviously, it is better to take meaningful measures to achieve an acceptable balance now than to wait for the blind and extremely painful action of the laws of nature, which would lead to a reduction in the population. 展开更多
关键词 Planet’s Response Human Activity EVOLUTION
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Evaluation of the Antimicrobial Activity of Endophytic Fungus Isolated from <i>Cocos nucifera</i>(L.) Cotyledon against Medically-Important Pathogens 认领
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作者 Byran N. Fuego Kyla G. Romano +1 位作者 Charlmaine D. Pinlac Gary Antonio C. Lirio 《生物科学与医学(英文)》 2021年第1期86-97,共12页
The study aimed to evaluate the endophytic fungi isolated from <em>Cocos nucifera</em> (L.) cotyledon for their possible antimicrobial activity. A total of twelve endophytic fungal species were successfull... The study aimed to evaluate the endophytic fungi isolated from <em>Cocos nucifera</em> (L.) cotyledon for their possible antimicrobial activity. A total of twelve endophytic fungal species were successfully isolated, from which five were selected and presumptively identified, including <em>Aspergillus niger</em>, <em>Raffaelea sp.</em>, <em>Aspergillus flavus</em>, <em>Cladosporium sp.</em> and <em>Pseudallescheria spp.</em> based on their macro and microscopic characters. The agar blocks of actively growing pure culture were assessed for antibacterial activity against five human pathogenic bacterial and fungal strains: <em>Escherichia coli</em> (BIOTECH 1634), <em>Bacillus subtilis</em> (BIOTECH 1697), <em>Staphylococcus aureus</em> (BIOTECH 1592), <em>Serratia marcescens</em> (BIOTECH 1748), and <em>Candida tropicalis</em> (BIOTECH 2085). Among the selected five endophytic used for antimicrobial activity screening, the <em>Raffaelea sp.</em> (CN-EF 2) has shown a high zone of inhibition of 11 mm against <em>Bacillus subtilis</em>, 18 mm against <em>Escherichia coli</em>, 15 mm against <em>Staphylococcus aureus</em>, and 11 mm against <em>Candida tropicalis</em>. Correspondingly, <em>Aspergillus niger</em> (CN-EF 1) has shown a zone of inhibition of 16 mm against <em>C. tropicalis</em>. The endophytic fungus <em>Raffaelea sp.</em> was effective against all test organisms except for <em>Serratia marcescens</em>, while <em>Aspergillus niger</em> was only effective for pathogenic fungi <em>C. albicans</em>. Hence, further in-depth studies of the isolated endophytic fungi are needed to determine the mechanisms behind the endophytes’ inhibitory effects. 展开更多
关键词 Endophytic Fungi Antimicrobial Activity Cocos nucifera L. Natural Product Agar Plug Diffusion Medically-Important Pathogens
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Effects of Pre-Schooler Lifestyle on the Circadian Rhythm of Secretory Immunoglobulin A 认领
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作者 Takaaki Miyake Yoshiharu Tanaka +2 位作者 Haruka Kawabata Shinya Saito Megumi Oda 《健康(英文)》 2021年第2期178-187,共10页
Assuming that secretory immunoglobulin A (s-IgA) in pre-schoolers is influenced by wake-up time, bedtime, sleeping duration and activity, the current study examined the influence of basic pre-schooler lifestyle on the... Assuming that secretory immunoglobulin A (s-IgA) in pre-schoolers is influenced by wake-up time, bedtime, sleeping duration and activity, the current study examined the influence of basic pre-schooler lifestyle on the circadian rhythm of s-IgA. We conducted a questionnaire survey on lifestyle and measured steps, heart rate and salivary s-IgA in 44 pre-schoolers aged 4 or 5 years old. Saliva was collected over 2 days at six time points: bedtime, upon waking up, upon arriving at nursery school, before lunch, after lunch and upon going home. To obtain relatively reliable s-IgA values, the s-IgA concentration/total protein concentration ratio (referred to as s-IgA/T.P.) was calculated. Relationship between the s-IgA/T.P. and heart rate, steps, wake-up time, bedtime and sleeping duration was then examined using Pearson’s correlation coefficient. Accordingly, pre-schooler lifestyle had the following effect on circadian rhythm of s-IgA: 1) s-IgA/T.P. values were higher upon waking up than at other measurement time points;2) pre-schoolers with considerable physical activity had high s-IgA/T.P. at bedtime and upon waking up;and 3) pre-schoolers with long sleeping durations and early bedtime had high s-IgA/T.P. upon waking up. Thus, our results confirmed that pre-schoolers’ lifestyle habits, such as bedtime, sleeping duration, physical activity, had an effect on the circadian rhythm of s-IgA. 展开更多
关键词 Pre-Schooler S-IGA LIFESTYLE ACTIVITY SLEEP
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DFT Study of Dimerization Sites in Imidazo[1,2-a]pyridinyl-chalcone Series 认领
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作者 Bibata Konate Sopi Thomas Affi Nahossé Ziao 《计算化学(英文)》 2021年第1期1-17,共17页
Quantum chemistry methods were performed in order to characterize the chemical reactivity on series of imidazo[1,2-a]pyridinyl-chalcone (IPC). In particular, the B3LYP/6-311G(d) theory level has been used to determine... Quantum chemistry methods were performed in order to characterize the chemical reactivity on series of imidazo[1,2-a]pyridinyl-chalcone (IPC). In particular, the B3LYP/6-311G(d) theory level has been used to determine parameters which characterize the global and local reactivity on five molecules of the series. These compounds differ from one to another with the aryl groups. There are: 1-(2-methylimidazo[1,2-a]pyridin-3-yl)-3-phenylprop-2-en-1-one, 3-(4-fluorophenyl)-1-(2-methylimidazo [1,2-a]pyridin-3-yl)prop-2-en-1-one, 3-[4-(dimethylamino)phenyl]-1-(2-methylimidazo [1,2-a]pyridin- 3-yl)prop-2-en-1-one, 3-(2,4-dichlorophenyl)-1-(2-methylimidazo [1,2-a]pyridin-3-yl)prop-2-en-1-one, 3-(2,4-dichlorophenyl)-1-(2-methylimidazo [1,2-a]pyridin-3-yl)prop-2-en-1-one. All results lead to finding out that local nucleophilicity and electrophilicity of compounds are not substituent-dependant contrarily to their global nucleophilicity which prove to be more sensitive to the electron-donating character of the substituents. 3-[4-(Dimethylamino) phenyl]-1-(2-methylimidazo[1,2-a]pyridin-3-yl)prop-2-en-1-one was identified as the unique nucleophile compound by global reactivity. Respectively, the carbon atoms C5 and C14 are the prediction sites of electrophilic and nucleophilic attacks in the molecular skeleton of both molecules. Identification of interactions centres on IPC series is of great importance for organic synthesis and medicinal chemistry where the molecular hybridization strategy is very often used to improve biological activities of interesting therapeutic systems. 展开更多
关键词 Chemical Reactivity Conceptual DFT Imidazopyridinyl-Chalcone Nematicidal Activity Quantum Chemistry
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Metal Complexes with 8-Hydroxyquinoline: Synthesis and <i>In Vitro</i>Antimicrobial Activity 认领
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作者 Amira Cipurković Emir Horozić +3 位作者 Snjež ana Marić Lejla Mekić Halid Junuzović 《应用科学(英文)》 2021年第1期1-10,共10页
In this paper, three complexes with 8-hydroxyquinoline (8-HQ) were synthesized, their spectral analysis was performed and the antimicrobial effect was examined <em>in vitro</em>. The stoichiometric ratio o... In this paper, three complexes with 8-hydroxyquinoline (8-HQ) were synthesized, their spectral analysis was performed and the antimicrobial effect was examined <em>in vitro</em>. The stoichiometric ratio of the complex was determined conductometrically and spectrophotometrically. FTIR and UV/VIS spectroscopy were used for structural characterization. Antimicrobial activity was examined by diffusion technique on selected gram-positive and gram-negative bacteria, and<em> C. albicans</em>. Square planar and octahedral geometry complexes were synthesized by mixing in a molar ratio of 1:2 (M:L). Based on the spectral data, it is concluded that both oxygen and nitrogen atoms from 8-HQ are involved in the formation of the complex. The antimicrobial activity of the complexes is high, with zones of inhibition in the range of 15 - 28 mm. 8-HQ was shown to have a significantly higher ability to inhibit the growth of the tested microorganisms. 展开更多
关键词 8-HQ Metal Complex Antimicrobial Activity In Vitro Study
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HPTLC Phytochemical Screening and Hydrophilic Antioxidant Activities of <i>Apium graveolens</i>L., <i>Cleome gynandra</i>L., and <i>Hibiscus sabdariffa</i>L. Used for Diabetes Management 认领
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作者 Moumouni Koala Alphonsine Ramde-Tiendrebeogo +4 位作者 Noufou Ouedraogo Sylvain Ilboudo Boukaré Kaboré Félix B. Kini Sylvin Ouedraogo 《美国分析化学(英文)》 2021年第1期15-28,共14页
Diabetes mellitus is a socially significant disease characterized by chronic hyperglycemia and metabolic disorders of proteins, carbohydrates, and lipids due to reduced function of insulin. Medicinal plants, rich in b... Diabetes mellitus is a socially significant disease characterized by chronic hyperglycemia and metabolic disorders of proteins, carbohydrates, and lipids due to reduced function of insulin. Medicinal plants, rich in bioactive components that promote prevention and treatment, are inexpensive and no side effects. <i>Apium graveolens</i>, <i>Cleome gynandra</i>, and <i>Hibiscus sabdariffa</i> from Burkina Faso were investigated for their phytochemical profile and antioxidant activities. The high-performance thin-layer chromatography profile revealed flavonoids, tannins, and sterols in these herbaceous. The <i>Hibiscus sabdariffa</i> methanolic extract exhibited the highest total phenolic (138.4 ± 0.5 mg GAE/g DW) and flavonoid (52.8 ± 0.6 mg RuE/g DW) contents comparatively to <i>Cleome gynandra</i> and <i>Apium graveolens</i>. <i>Hibiscus sabdariffa</i> methanolic extract also presented the highest antioxidant activity (IC<sub>50</sub> = 0.31 ± 0.002 mg/mL) using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity assay. A high correlation between flavonoid contents and hydrophilic antioxidant activities (r = 0.99) was observed, indicating that flavonoids contribute significatively to these herbaceous antioxidant properties. <i>Apium graveolens</i>, <i>Cleome gynandra, and <i>Hibiscus sabdariffa</i> constitute a natural source of phenolic compounds that could be exploited in diabetes mellitus management.</i> 展开更多
关键词 Diabetes Mellitus Medicinal Plants Flavonoids Contents Hydrophilic Antioxidant Activity HPTLC Screening
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Plant Growth Promoting Rhizobacteria as Biological Control Agent in Rice 认领
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作者 Duangkhaetita Kanjanasopa Wanthakarn Aiedhet +1 位作者 Suraphon Thitithanakul Chanyarat Paungfoo-Lonhienne 《农业科学(英文)》 2021年第1期1-8,共8页
The use of agrochemical products to combat diseases in crops has adverse effects on the environment and human health. Plant growth promoting rhizobacterium (PGPR) has been increasingly proposed as an eco-friendly alte... The use of agrochemical products to combat diseases in crops has adverse effects on the environment and human health. Plant growth promoting rhizobacterium (PGPR) has been increasingly proposed as an eco-friendly alternative in agriculture. PGPRs have beneficial effects not only in promoting plant growth but also have shown their potential as biological control agent, being able to inhibit plant pathogens. Here, we investigated the use of PGPR <em>Paraburkholderia</em> sp. strain SOS3 to provide disease protection in rice (<em>Oryza sativa</em> L.). The antagonistic activity of SOS3 against five fungal pathogens of rice was assessed by dual culture on plates and on rice seedlings. The results showed that on plate assay, SOS3 inhibits the growth of <em>Curvularia lunata</em>, <em>Rhizoctonia solani</em>, <em>Pyricularia oryzae</em>, <em>Helminthosporium oryzae</em>, and <em>Fusarium moniliforme</em> by 17.2%, 1.1%, 8.3%, 32.5%, and 35.4%, respectively. When inoculated on rice seeds, SOS3 promotes seed germination and significantly reduces disease symptoms in plants infected with <em>R. solani</em>. These results suggest that SOS3 has a great potential to be used in rice agriculture to combat the “Sheath Blight” disease. 展开更多
关键词 Antifungal Activity BIOCONTROL RICE Fungal Pathogen Sustainable Agriculture Plant Growth-Promoting Rhizobacteria
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Determination of Fatty Acid Composition by GC-MS and Potential Antioxidant and Antibacterial Properties of Rumex hastatus and Cytisus scoparius Seeds Grown in Kashmir 认领
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作者 Zubair Rehman Nengroo Abdul Rauf +1 位作者 Shayeeb Ahmad Bhat Muzammil Sharief Dar 《药剂与药理学:英文版》 2021年第2期64-78,共15页
Rumex hastatus D. Don and Cytisus scoparius Linn. are medicinally important plants used in Ayurveda and food, areenriched with remarkable nervine, diuretic, sedative and various other therapeutic properties. In this s... Rumex hastatus D. Don and Cytisus scoparius Linn. are medicinally important plants used in Ayurveda and food, areenriched with remarkable nervine, diuretic, sedative and various other therapeutic properties. In this study Soxhlet extractionproduces higher yield of seed extracts. Gas chromatography-mass spectrometry was used to determine fatty acid composition ofpetroleum ether extracts (PE). The major fatty acids were Linolenic acid 53.53% in R. hastatus and linoleic acid 59.42% in C.scoparius. Palmitic acid was also found in significant amount (16.58% and 19.33%) in R. hastatus and C. scoparius respectively. Thechloroform (RCF, CCF), ethyl acetate (REA, CEA), acetone (RAT, CAT) and methanol (RMT, CMT) extracts of R. hastaus and C.scoparius respectively, were examined for their antioxidant activity using 2,2-di-phenyl-1-picrylhydrazyl (DPPH), nitrobluetetrazolium (NBT), hydrogen peroxide (H2O2), 2,2ˈ-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavengingassay and antibacterial activity against Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus by Agar disc diffusionmethod. All the extracts showed good radical scavenging and antibacterial activities compared to butylated hydroxyltoluene andstreptomycin respectively. However, dominant radical scavenging effect was observed at 100 μg/mL and 200 μg/mL concentrationsof extracts and dominant zone of inhibition was shown by CAT, CMT, RAT and REA extracts. This study exhibited beneficialproperties of these plants as an ingredient (unsaturated fatty acids) for the formulation of various functional foods and a source ofnatural antioxidant and antibacterial agents for drug, design and development. 展开更多
关键词 Soxhlet extraction Linoleic acid Linolenic acid Antibacterial activity Antioxidant activity
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关于建立铁路运输成本标准的思考 认领
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作者 赵晨 宋雨玲 +1 位作者 吕成文 唐恩斌 《铁道经济研究》 2021年第1期1-5,47,共6页
在分析铁路运输成本标准特点及应用目标的基础上,提出了构建铁路运输成本标准的原则和总体框架,按照不同作业活动的特点和成本变化规律的差异性将作业成本定额分为三类,分别探讨了三类作业成本定额的测定及差异处理问题。从数据和标准... 在分析铁路运输成本标准特点及应用目标的基础上,提出了构建铁路运输成本标准的原则和总体框架,按照不同作业活动的特点和成本变化规律的差异性将作业成本定额分为三类,分别探讨了三类作业成本定额的测定及差异处理问题。从数据和标准化、配套制度、信息技术应用等方面提出了构建成本标准体系的相关建议。 展开更多
关键词 成本标准 铁路运输成本标准 定额 作业 作业成本
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The Physiological Effects of a Walking to Music Intervention in Adults with Intermediate Hyperglycemia 认领
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作者 Maria Faulkner Marie Murphy +6 位作者 Gareth Davison David Rowe Allan Hewitt Alan Nevill Ellie Duly Tom Trinick Andrea M. McNeilly 《内分泌与新陈代谢疾病期刊(英文)》 2021年第1期43-61,共19页
<p align="justify"> <span style="font-family:Verdana;"><strong>Purpose:</strong> Overweight individuals are at risk of intermediate hyperglycemia (IHG) [<a href="#re... <p align="justify"> <span style="font-family:Verdana;"><strong>Purpose:</strong> Overweight individuals are at risk of intermediate hyperglycemia (IHG) [<a href="#ref1">1</a>]. Increasing physical activity (PA) in IHG is one method to reduce the risk of glucometabolic and cardiovascular (CV) complications [<a href="#ref2">2</a>]. This study investigates walking to music as a modality to increase moderate intensity PA and regulate glucometabolic disturbances. <strong>Patients and Methods: </strong>Participants were randomized to usual care (UC) or intervention group (IG) who completed a 6 month walking to music program. Physiological assessments for a range of variables (DEXA, flow mediated dilatation (FMD) and glucometabolic biomarkers) were completed at baseline, 4, 6 and 9 months (follow-up). <strong>Results:</strong> For IG group, walking compliance decreased with time however 71.4%, 79.5% and 73% of walking completed was moderate intensity at 4, 6 and 9 months. At 6 months IG FMD was significantly lower than UC and HbA1Cwas 5% lower. Other physiological markers were not altered. <strong>Conclusion:</strong> Walking to music may be a novel method to encourage moderate intensity PA. However, the majority of results demonstrate that this intervention was not more effective than UC in managing glucometabolic and CV biomarkers in IHG. Future interventions should include additional support for the entire study duration however this has cost implications.</span> </p> 展开更多
关键词 Physical Activity CADENCE Diabetic Health
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文章速递卵磷脂及复合物的功能活性研究进展 认领
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作者 宫璇 齐筱莹 +6 位作者 赵志康 逄昕雨 郭梦雪 叶张靖 王友军 李欣玉 卢航 《食品与发酵工业》 CAS CSCD 北大核心 2021年第6期295-299,共5页
卵磷脂即磷酸基团的磷脂酰胆碱,是生物膜的基本成分。卵磷脂复合物指磷脂分子和活性成分通过电荷迁移作用形成的较为稳定的化合物或络合物,它可使活性分子的理化性质发生改变,提高其生物利用度。卵磷脂来源广泛,卵磷脂复合物制备方法简... 卵磷脂即磷酸基团的磷脂酰胆碱,是生物膜的基本成分。卵磷脂复合物指磷脂分子和活性成分通过电荷迁移作用形成的较为稳定的化合物或络合物,它可使活性分子的理化性质发生改变,提高其生物利用度。卵磷脂来源广泛,卵磷脂复合物制备方法简单,近年来在药物制剂方面特别是在中西药卵磷脂复合物应用研究逐渐增多,并取得了较大的成果。该文对卵磷脂与活性成分的复合机理及卵磷脂复合物的种类和功能活性进行概述。 展开更多
关键词 磷脂 卵磷脂复合物 活性
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文章速递Paleoenvironment and organic matter enrichment of the Carboniferous volcanic-related source rocks in the Malang Sag,Santanghu Basin,NW China 认领
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作者 Tian-Jun Li Zhi-Long Huang +2 位作者 Xuan Chen Xin-Ning Li Jun-Tian Liu 《石油科学:英文版》 SCIE CAS CSCD 2021年第1期29-53,共25页
Volcanic activity was quite frequent during the deposition of the Late Carboniferous Ha’erjiawu Formation in the Santanghu Basin.The petrology and organic and inorganic geochemical indicators were used to investigate... Volcanic activity was quite frequent during the deposition of the Late Carboniferous Ha’erjiawu Formation in the Santanghu Basin.The petrology and organic and inorganic geochemical indicators were used to investigate hydrocarbon potential,paleoenvironmental conditions and organic matter enrichment of the mudstones.The results show that the oil generation capacity of the Ha’erjiawu Formation mudstones,which has abundant oil-prone organic matter(TypeⅡkerogen with hydrogen index values mainly ranging from 250 to 550 mg HC/g TOC)in mature stage(Tmax values mainly ranging from 435 to 450℃),is considerable.The Ha’erjiawu Formation was deposited in a dysoxic,freshwater-mildly brackish,and warm-humid environment.During its deposition,the Ha’erjiawu Formation received hydrothermal inputs.The volcanic hydrothermal activities played an important role in the organic matter enrichment.In addition,the total organic carbon(TOC)is significantly positively correlated with the felsic mineral content,but it is negatively correlated with the carbonate mineral content and C27/C29 ratios,indicating that terrigenous organic matter input also contributed to the primary productivity in the surface water.Therefore,the formation of the high-quality source rocks in the Ha’erjiawu Formation was jointly affected by the hydrothermal activity and the terrigenous organic matter input. 展开更多
关键词 Organic-rich rocks Paleoenvironment Organic matter enrichment Hydrothermal activity Ha’erjiawu Formation Santanghu Basin
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