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Igor Pereira da Silva Elson Brissow Luis Claudio Kellner Filho Jaqueline Senabio Kátia Aparecida de Siqueira Samuel Vandresen Filho Jaqueline Lopes Damasceno Suzana Amorim Mendes Denise Crispim Tavares Lizandra Guidi Magalhães Policarpo Ademar Sales Junior Ana Helena Januário Marcos Antônio Soares 《World journal of microbiology & biotechnology》2017,33(3):62
The compounds terrein (1), butyrolactone I (2), and butyrolactone V (3) were isolated from the ethyl acetate extract (EtOAc) of the endophytic fungus Aspergillus terreus—F7 obtained from Hyptis suaveolens (L.) Poit. The extract and the compounds presented schistosomicidal activity against Schistosoma mansoni; at 100 µg/mL for EtOAc extract, 1297.3 µM for compound 1, 235.6 µM for compound 2, and 454.1 µM for compound 3, they killed 100% of the parasites after 72 h of treatment. Compounds 1, 2, and 3 exerted moderate leishmanicidal activity against Leishmania amazonensis (IC50 ranged from 23.7 to 78.6 µM). At 235.6 and 227.0 µM, compounds 2 and 3, respectively, scavenged 95.92 and 95.12% of the DPPH radical (2,2-diphenyl-1-picryl-hydrazyl), respectively. Regarding the cytotoxicity against the breast tumor cell lines MDA-MB-231 and MCF-7, compound 2 gave IC50 of 34.4 and 17.4 µM, respectively, while compound 3 afforded IC50 of 22.2 and 31.9 µM, respectively. At 117.6 µM, compound 2 inhibited the growth of and killed the pathogen Escherichia coli (ATCC 25922). Compounds 1, 2, and 3 displayed low toxicity against the normal line of human lung fibroblasts (GM07492A cells), with IC50 of 15.3?×?103, 3.4?×?103, and 5.8?×?103 µM, respectively. This is the first report on (i) the in vitro schistosomicidal and leishmanicidal activities of the EtOAc extract of A. terreus—F7 and compounds 1, 2, and 3; and (ii) the antitumor activity of compounds 2 and 3 against MDA-MB-231 and MCF-7 cells. 相似文献
3.
Franziska Wendt Christian Näther Felix Tuczek 《Journal of biological inorganic chemistry》2016,21(5-6):777-792
Four new imidazole-based ligands, 4-((1H-imidazol-4-yl)methyl)-2-phenyl-4,5-dihydrooxyzole (L OL 1), 4-((1H-imidazol-4-yl)methyl)-2-(tert-butyl)-4,5-dihydrooxyzole (L OL 2), 4-((1H-imidazol-4-yl)methyl)-2-methyl-4,5-dihydrooxyzole (L OL 3), and N-(2,2-dimethylpropylidene)-2-(1-trityl-1H-imidazol-4-yl-)ethyl amine (L imz 1), have been synthesized. The corresponding copper(I) complexes [Cu(I)(L OL 1)(CH3CN)]PF6 (CuL OL 1), [Cu(I)(L OL 2)(CH3CN)]PF6 (CuL OL 2), [Cu(I)(L OL 3)(CH3CN)]PF6 (CuL OL 3), [Cu(I)(L imz 1)(CH3CN)2]PF6 (CuL imz 1) as well as the Cu(I) complex derived from the known ligand bis(1-methylimidazol-2-yl)methane (BIMZ), [Cu(I)(BIMZ)(CH3CN)]PF6 (CuBIMZ), are screened as catalysts for the oxidation of 3,5-di-tert-butylcatechol (3,5-DTBC-H2) to 3,5-di-tert-butylquinone (3,5-DTBQ). The primary reaction product of these oxidations is 3,5-di-tert-butylsemiquinone (3,5-DTBSQ) which slowly converts to 3,5-DTBQ. Saturation kinetic studies reveal a trend of catalytic activity in the order CuL OL 3 ≈ CuL OL 1 > CuBIMZ > CuL OL 2 > CuL imz 1. Additionally, the catalytic activity of the copper(I) complexes towards the oxygenation of monophenols is investigated. As substrates 2,4-di-tert-butylphenol (2,4-DTBP-H), 3-tert-butylphenol (3-TBP-H), 4-methoxyphenol (4-MeOP-H), N-acetyl-l-tyrosine ethyl ester monohydrate (NATEE) and 8-hydroxyquinoline are employed. The oxygenation products are identified and characterized with the help of UV/Vis and NMR spectroscopy, mass spectrometry, and fluorescence measurements. Whereas the copper complexes with ligands containing combinations of imidazole and imine functions or two imidazole units (CuL imz 1 and CuBIMZ) are found to exhibit catalytic tyrosinase activity, the systems with ligands containing oxazoline just mediate a stoichiometric conversion. Correlations between the structures of the complexes and their reactivities are discussed. 相似文献
4.
Ntombenhle H. Gama Afag Y. F. Elkhadir Bhavna G. Gordhan Bavesh D. Kana James Darkwa Debra Meyer 《Biometals》2016,29(4):637-650
Treatment of human immunodeficiency virus (HIV) is currently complicated by increased prevalence of co-infection with Mycobacterium tuberculosis. The development of drug candidates that offer the simultaneous management of HIV and tuberculosis (TB) would be of great benefit in the holistic treatment of HIV/AIDS, especially in sub-Saharan Africa which has the highest global prevalence of HIV-TB coinfection. Bis(diphenylphosphino)-2-pyridylpalladium(II) chloride (1), bis(diphenylphosphino)-2-pyridylplatinum(II) chloride (2), bis(diphenylphosphino)-2-ethylpyridylpalladium(II) chloride (3) and bis(diphenylphosphino)-2-ethylpyridylplatinum(II) (4) were investigated for the inhibition of HIV-1 through interactions with the viral protease. The complexes were subsequently assessed for biological potency against Mycobacterium tuberculosis H37Rv by determining the minimal inhibitory concentration (MIC) using broth microdilution. Complex (3) showed the most significant and competitive inhibition of HIV-1 protease (p = 0.014 at 100 µM). Further studies on its in vitro effects on whole virus showed reduced viral infectivity by over 80 % at 63 µM (p < 0.05). In addition, the complex inhibited the growth of Mycobacterium tuberculosis at an MIC of 5 µM and was non-toxic to host cells at all active concentrations (assessed by tetrazolium dye and real time cell electronic sensing). In vitro evidence is provided here for the possibility of utilizing a single metal-based compound for the treatment of HIV/AIDS and TB. 相似文献
5.
Abhishek K. Singh Suchita Prasad Bipul Kumar Shiv Kumar Amitesh Anand Shashank S. Kamble Sunil K. Sharma Hemant K. Gautam 《Indian journal of microbiology》2017,57(4):499-502
Four (1, 2, 4 and 6) synthetic quaternary ammonium derivatives of pyranochromenones and (coumarinyloxy)acetamides were synthesized and investigated for their antimicrobial efficacy on MRSA (Methicillin-resistant Staphylococcus aureus), and multi-drug resistant Pseudomonas aeruginosa, Salmonella enteritidis and Mycobacterium tuberculosis H37Rv strain. One of the four compounds screened i.e. N,N,N-triethyl-10-((4,8,8-trimethyl-2-oxo-2,6,7,8-tetrahydropyrano[3,2-g]chromen-10-yl)oxy)decan-1-aminium bromide (1), demonstrated significant activity against S. aureus, P. aeruginosa and M. tuberculosis with MIC value of 16, 35, and 15.62 µg/ml respectively. The cytotoxicity evaluation of compound 1 on A549 cell lines showed it to be a safe antimicrobial molecule, TEM study suggested that the compound led to the rupture of the bacterial cell walls. 相似文献
6.
Mariem Wali Benet Gunsè Mercè Llugany Isabel Corrales Chedly Abdelly Charlotte Poschenrieder Tahar Ghnaya 《Planta》2016,244(2):333-346
Main conclusion
NaCl alleviates Cd toxicity in Sesvium portulacastrum by maintaining plant water status and redox balance, protecting chloroplasts structure and inducing some potential Cd 2+ chelators as GSH and proline. It has been demonstrated that NaCl alleviates Cd-induced growth inhibition in the halophyte Sesuvium portulacastrum. However, the processes that mediate this effect are still unclear. In this work we combined physiological, biochemical and ultrastructural studies to highlight the effects of salt on the redox balance and photosynthesis in Cd-stressed plants. Seedlings were exposed to different Cd concentrations (0, 25 and 50 µM Cd) combined with low (0.09 mM) (LS), or high (200 mM) NaCl (HS) in hydroponic culture. Plant–water relations, photosynthesis rate, leaf gas exchange, chlorophyll fluorescence, chloroplast ultrastructure, and proline and glutathione concentrations were analyzed after 1 month of treatment. In addition, the endogenous levels of stress-related hormones were determined in plants subjected to 25 µM Cd combined with both NaCl concentrations. In plants with low salt supply (LS), Cd reduced growth, induced plant dehydration, disrupted chloroplast structure and functioning, decreased net CO2 assimilation rate (A) and transpiration rate (E), inhibited the maximum potential quantum efficiency (Fv/Fm) and the quantum yield efficiency (Φ PSII) of PSII, and enhanced the non-photochemical quenching (NPQ). The addition of 200 mM NaCl (HS) to the Cd-containing medium culture significantly mitigated Cd phytotoxicity. Hence, even at similar internal Cd concentrations, HS-Cd plants were less affected by Cd than LS-Cd ones. Hence, 200 mM NaCl significantly alleviates Cd-induced toxicity symptoms, growth inhibition, and photosynthesis disturbances. The cell ultrastructure was better preserved in HS-Cd plants but affected in LS-Cd plants. The HS-Cd plants showed also higher concentrations of reduced glutathione (GSH), proline and jasmonic acid (JA) than the LS-Cd plants. However, under LS-Cd conditions, plants maintained higher concentration of salicylic acid (SA) and abscisic acid (ABA) than the HS-Cd ones. We conclude that in S. portulacastrum alleviation of Cd toxicity by NaCl is related to the modification of GSH and proline contents as well as stress hormone levels thus protecting redox balance and photosynthesis.7.
Xinjun Zhang Hongtao He Rong Ma Zengchun Ji Qi Wei Huanqin Dai Lixin Zhang Fuhang Song 《Journal of industrial microbiology & biotechnology》2017,44(4-5):589-594
Since the discovery of the first antibiotic, natural products have played an important role in chemistry, biology and medicine. To explore the potential of bioactive compounds from microbes isolated from the southeast of Tibet, China, a crude extract library was constructed and screened against Staphylococcus aureus. The strain Nocardiopsis sp. LS150010 was scaled up and subjected to further chemical studies, resulting in the identification of N-salicyloyl-2-aminopropan-1,3-diol (2) and its rare aziridine derivative, madurastatin B3 (1). Their structures were determined by detailed analysis of 1D, 2D NMR and HRMS data. Compounds 1 and 2 displayed significant inhibitory activity against S. aureus and methicillin resistant S. aureus, with MIC values of 6.25 µg/mL. Compound 1 also showed potent inhibitory activity against Bacillus subtilis and Escherichia coli, as well as activity in a Mycobacterium tuberculosis Bacillus Calmette-Guérin infected THP-1 cell model. 相似文献
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Marcio Paulo Pereira Luiz Carlos de Almeida Rodrigues Felipe Fogaroli Corrêa Evaristo Mauro de Castro Vinícius Erlo Ribeiro Fabricio José Pereira 《Trees - Structure and Function》2016,30(3):807-814
Key message
Low concentrations of cadmium cause anatomical responses in leaf chlorenchyma enhancing Schinus molle photosynthesis and tolerance.Abstract
This work is aimed to evaluate the effects of cadmium (Cd) on leaf anatomy and photosynthesis in Schinus molle, a species that can cope with harsh environments. Seven-month-old S. molle plants were exposed over 90 days to varying Cd concentrations (0, 10, 20, 50, 125 or 250 µM using Cd(NO3)2 as the Cd source). The plants were placed in vases containing washed sand and vermiculite as the substrate and nutrient solution. Throughout the experiment, the substrate was maintained at field capacity, and the nutrient solution was replaced at 15-day intervals. After 90 days, leaves were collected and processed for anatomical analysis using typical plant microtechniques. In addition, plant growth, photosynthesis, chlorophyll content and A/Ci curve were evaluated using an infrared gas analyzer. S. molle growth was not affected by Cd. Lower Cd concentrations (10 and 20 µM) resulted in greater net photosynthesis, stomatal conductance and density, Vcmax, Jmax and mesophyll thickness. However, Cd concentrations of 50 µM or greater resulted in a reduction of most of the evaluated characteristics to levels close to control. All of the tested Cd concentrations resulted in reduced chlorophyll content and stomatal size. Therefore, the effect of Cd in a tolerant species such as S. molle is concentration dependent, and at low Cd concentrations, these plants can cope with the toxicity by adjusting leaf structure and function.9.
Yike Han Fengyue Zhao Shang Gao Xianyun Wang Aimin Wei Zhengwu Chen Nan Liu Xueqiang Tong Xinmeng Fu Changlong Wen Zhenxian Zhang Ningning Wang Shengli Du 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(2):449-460
Key message
The cucumber male sterility gene ms - 3 was fine mapped in a 76 kb region harboring an MMD1 -like gene Csa3M006660 that may be responsible for the male sterile in cucumber.Abstract
A cucumber (Cucumis sativus L.) male sterile mutant (ms-3) in an advanced-generation inbred line was identified, and genetic analysis revealed that the male sterility trait was controlled by a recessive nuclear gene, ms-3, which was stably inherited. Histological studies suggested that the main cause of the male sterility was defective microsporogenesis, resulting in no tetrad or microspores being formed. Bulked segregant analysis (BSA) and genotyping of an F2 population of 2553 individuals were employed used to fine map ms-3, which was delimited to a 76 Kb region. In this region, a single non-synonymous SNP was found in the Csa3M006660 gene locus, which was predicted to result in an amino acid change. Quantitative RT-PCR analysis of Csa3M006660 was consistent with the fact that it plays a role in the early development of cucumber pollen. The protein encoded by Csa3M006660 is predicted to be homeodomain (PHD) finger protein, and the high degree of sequence conservation with homologs from a range of plant species further suggested the importance of the ms-3 non-synonymous mutation. The data presented here provide support for Csa3M006660 as the most likely candidate gene for Ms-3.10.
Mahmood Hossain Chameli Saha S. M. Rubaiot Abdullah Sanjoy Saha Mohammad Raqibul Hasan Siddique 《Trees - Structure and Function》2016,30(3):709-717
Key message
Present study recommends DBH as independent variable of the derived allometric models and Biomass = a + b DBH 2 has been selected for total above-ground biomass, nutrients and carbon stock.Abstract
Kandelia candel (L.) Druce is a shrub to small tree of the Sundarbans mangrove forest of Bangladesh. The aim of the study was to derive the allometric models for estimating above-ground biomass, nutrient and carbon stock in K. candel. A total of eight linear models with 64 regression equations were tested to derive the allometric models for biomass of each part of plant; and nutrients and carbon stock in total above-ground biomass. The best fitted allometric models were selected by considering the values of R 2, CV, R mse, MSerror, S a, S b, F value, AICc and Furnival Index. The selected allometric models were Biomass = 0.014 DBH2 + 0.03; √Biomass = 0.29 DBH ? 0.21; √Biomass = 0.66 √DBH ? 0.57; √Biomass = 1.19 √DBH ? 1.02; Biomass = 0.21 DBH2 + 0.12 for leaves, branches, bark, stem without bark and total above-ground biomass, respectively. The selected allometric models for Nitrogen, Phosphorous, Potassium and Carbon stock in total above-ground biomass were N = 0.39 DBH2 + 0.49, P = 0.77 DBH2 + 0.14, K = 0.87 DBH2 + 0.07 and C = 0.09 DBH2 + 0.05, respectively. The derived allometric models have included DBH as a single independent variable, which may give quick and accurate estimation of the above-ground biomass, nutrient and carbon stock in this species. This information may also contribute to a broader study of nutrient cycling, nutrient budgeting and carbon sequestration of the studied forest.11.
Chengqian Pan Yutong Shi Bibi Nazia Auckloo Syed Shams ul Hassan Najeeb Akhter Kuiwu Wang Ying Ye Chen-Tung Arthur Chen Xinyi Tao Bin Wu 《Marine biotechnology (New York, N.Y.)》2017,19(5):469-479
Five new compounds were isolated from Penicillium sp. Y-5-2 including an austin derivative 4, four isocoumarins 9, 11, 12, and 13, together with two known isocoumarins 8 and 10, and six known austin derivatives 1, 2, 3, 5, 6, and 7 and one phenol 14. Their structures and relative configurations were established by spectroscopic means. The absolute configurations of 4, 11, and 13 were defined mainly by comparison of quantum chemical TDDFT calculated and experimental ECD spectra. The cyclization of the pentan-2-ol pendant at C-3 in compound 13 allowed the assignment of a new 2,3,4,4a,6,10b-hexahydro-1H-benzo[c]chromene isocoumarin skeleton. New compounds 9, 11, and 13 revealed inhibitory activities against E. coli at MIC values around 32 μg/mL. The known compound 14 showed potent antibiotic activity against Staphylococcus aureus and Bacillus subtilis with MIC values 8 and 2 μg/mL, respectively, with no cytotoxicity when tested in vitro. A rapid and efficient technique for selecting antibiotic fungal strain among eight marine-derived fungi was also described. 相似文献
12.
Plantago ovata Forsk is an annual herb with immense medicinal importance, the seed and husk of which is used in the treatment of chronic constipation, irritable bowel syndrome, diarrhea since ancient times. Zinc, an essential metal, is required by plants as they form important components of zinc finger proteins and also aid in synthesis of photosynthetic pigments such as chlorophyll. However, in excess amount Zn causes chlorosis of leaf and shoot tissues and generate reactive oxygen species. The present study is aimed at investigating the changes in expression levels of MT2 gene in Plantago ovata under zinc stress. Data show up to 1.66 fold increase in expression of PoMT2 in 1000 µM ZnSO4·7H2O treated sample. Our study also describes alteration of MT2 gene expressions in Plantago ovata as observed through Real time PCR (qPCR) done by \(2^{{ - \Delta \Delta}} C_T\) method. In this study we have observed an upregulation (or induction) in the PoMT2 gene expression level in 500 and 800 µM ZnSO4·7H2O treated samples but found saturation on further increasing the dose to 1000 µM of ZnSO4·7H2O. Determination of the phenotypic and biochemical changes in Plantago ovata due to exposure to zinc stress of concentrations 500, 800 and 1000 µM revealed oxidative stress. The enhanced expression of MT2 gene in Plantago ovata has a correlation with the increased total antioxidant activity and increased DPPH radical scavenging activity. 相似文献
13.
Key message
We investigated a Frankia – Alnus sieboldiana symbiosis, including the minimum inoculum dose for constant nodulation, the period of time to nodulation after inoculation, and the effects of N on nodulation.Abstract
Frankia is a nitrogen-fixing actinomycete that forms root nodules in some dicotyledonous plants, which are called actinorhizal. We studied nodule formation in Alnus sieboldiana, an actinorhizal plant, after inoculation with a Frankia isolate to establish techniques for Frankia inoculation and the cultivation of inoculated plants. Root nodules formed on seedlings of A. sieboldiana by 2 weeks after inoculation, and N2 fixation measured by acetylene reduction activity started 3 weeks after inoculation. Nodulation was observed after inoculation with a Frankia isolate at 0.001 μL packed cell volume (pcv). The number of nodules formed on the seedlings inoculated with Frankia at more than 0.05 μL pcv was not significantly different. Nodule development and N2 fixation were reduced when inoculated seedlings were treated weekly with 15 mM NH4NO3-N. In contrast, treatment with 3.75 or 0.9375 mM NH4NO3-N did not inhibit nodule development or N2 fixation of inoculated seedlings by 15 weeks of N treatment.14.
Ya-Jun Wang Bin-Bin Ying Min Chen Wei Shen Zhi-Qiang Liu Yu-Guo Zheng 《World journal of microbiology & biotechnology》2017,33(7):144
A new anti-Prelog short-chain dehydrogenase/reductase (SDR) encoding gene lcsdr was cloned from Lactobacillus composti DSM 18527, and heterologously expressed in Escherichia coli. LcSDR is nicotinamide adenine dinucleotide phosphate (NADPH)-dependent and has a molecular weight of approximately 30 kDa. The optimal pH and temperature were 6.5 and 30?°C, respectively. The maximal reaction rate Vmax was 133.9 U mg?1; the Michaelis–Menten constant K m of LcSDR were 0.345 mM for acetophenone (1a), and 0.085 mM for NADPH. Through introducing an EsGDH-catalyzed NADPH regeneration system, a biocatalytic process for (R)-1-phenylethanol ((R)-1b) was developed with outstanding time–space yield. Under the optimized conditions, 50 g l?1 1a was converted to (R)-1b in 2 h with a yield of 93.8%, enantiomeric excess of product (e.e.p) above 99% and space–time yield of 562.8 g l?1 d?1. 相似文献
15.
Vijay Kumar Simranjeet Singh Rohit Singh Niraj Upadhyay Joginder Singh 《Journal of chemical biology》2017,10(4):179-190
The present study was designed to synthesize the bioactive molecule 2,2-bis(2,4-dinitrophenyl)-2-(phosphonatomethylamino)acetate (1), having excellent applications in the field of plant protection as a herbicide. Structure of newly synthesized molecule 1 was confirmed by using the elemental analysis, mass spectrometric, NMR, UV-visible, and FTIR spectroscopic techniques. To obtain better structural insights of molecule 1, 3D molecular modeling was performed using the GAMESS programme. Microbial activities of 1 were checked against the pathogenic strains Aspergillus fumigatus (NCIM 902) and Salmonella typhimurium (NCIM 2501). Molecule 1 has shown excellent activities against fungal strain A. fumigates (35 μg/l) and bacterial strain S. typhimurium (25 μg/l). To check the medicinal significance of molecule 1, interactions with bovine serum albumin (BSA) protein were checked. The calculated value of binding constant of molecule 1–BSA complex was 1.4 × 106 M?1, which were similar to most effective drugs like salicylic acid. More significantly, as compared to herbicide glyphosate, molecule 1 has exhibited excellent herbicidal activities, in pre- and post-experiments on three weeds; barnyard grass (Echinochloa Crus), red spranglitop (Leptochloa filiformis), and yellow nuts (Cyperus Esculenfus). Further, effects of molecule 1 on plant growth-promoting rhizobacterial (PGPR) strains were checked. More interestingly, as compared to glyphosate, molecule 1 has shown least adverse effects on soil PGPR strains including the Rhizobium leguminosarum (NCIM 2749), Pseudomonas fluorescens (NCIM 5096), and Pseudomonas putida (NCIM 2847). 相似文献
16.
Chen Tan Cheng Cui Yi Xiang Xianhong Ge Zaiyun Li 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2017,130(12):2491-2504
Key message
We report the development and characterization of Brassica oleracea - nigra monosomic alien addition lines (MAALs) to dissect the Brassica B genome.Abstract
Brassica nigra (2n = 16, BB) represents the diploid Brassica B genome which carries many useful genes and traits for breeding but received limited studies. To dissect the B genome from B. nigra, the triploid F1 hybrid (2n = 26, CCB) obtained previously from the cross B. oleracea var. alboglabra (2n = 18, CC) × B. nigra was used as the maternal parent and backcrossed successively to parental B. oleracea. The progenies in BC1 to BC3 generations were analyzed by the methods of FISH and SSR markers to screen the monosomic alien addition lines (MAALs) with each of eight different B-genome chromosomes added to C genome (2n = 19, CC + 1B1?8), and seven different MAALs were established, except for the one with chromosome B2 which existed in one triple addition. Most of these MAALs were distinguishable morphologically from each other, as they expressed the characters from B. nigra differently and at variable extents. The alien chromosome remained unpaired as a univalent in 86.24% pollen mother cells at diakinesis or metaphase I, and formed a trivalent with two C-genome chromosomes in 13.76% cells. Transmission frequency of all the added chromosomes was far higher through the ovules (averagely 14.40%) than the pollen (2.64%). The B1, B4 and B5 chromosomes were transmitted by female at much higher rates (22.38–30.00%) than the other four (B3, B6, B7, B8) (5.04–8.42%). The MAALs should be valuable for exploiting the genome structure and evolution of B. nigra.17.
Four new platinum(II) complexes: PtII L1·H2O (C1, H2 L1 = C20H16N2O2), PtII L2Cl2 (C2, L2 = C22H16N2O2), PtII L3Cl2·H2O (C3, L3 = C20H16N2), PtII L4Cl2·0.4H2O (C4, L4 = C18H14N4) have been synthesized and characterized by using various physico-chemical techniques. The binding interaction of the four platinum(II) complexes C1–C4 with calf thymus (CT)-DNA has been investigated by UV–Vis and fluorescence emission spectrometry. The apparent binding constant (K app) values follow the order: C3 > C1 > C2 > C4. In addition, fluorescence spectrometry of bovine serum albumin (BSA) with the four platinum(II) complexes C1–C4 showed that the quenching mechanism might be a static quenching procedure. For C1–C4, the number of binding sites was about one for BSA and the binding constants follow the order: C3 (7.08 × 105M?1) > C1 (2.82 × 105M?1) > C2 (0.85 × 105M?1) > C4 (0.15 × 105M?1). With the single condition change such as absence of an external agent, the DNA cleavage abilities of C3 exhibit remarkable changes. In addition, the cytotoxicity of C3 in vitro on tumor cells lines (MCF-7, HepG2 and HT29) were examined by MTT and showed better antitumor effects on the tested cells. 相似文献
18.
Gabriela?R.?Luna-Palencia Ariana?A.?Huerta-Heredia Carlos?M.?Cerda-García-Rojas Ana?C.?Ramos-Valdivia
The alkaloids of Uncaria tomentosa micropropagated plantlets and root cultures were isolated and identified by NMR and mass spectrometry. Plantlets yielded pteropodine (1), isopteropodine (2), mitraphylline (3), isomitraphylline (4), uncarine F (5), speciophylline (6), rhynchophylline (7) and isorhynchophylline (8). In plantlets growing under continuous light, tetracyclic alkaloids 7 and 8 decreased from 20 ± 1.8 at 2 months to 2.2 ± 0.33 mg/g dry wt at 6 months, while the pentacyclic alkaloids 1–4 increased from 7.7 ± 1.4 to 15 ± 0.05 mg/g dry wt, supporting their biogenetic conversion. Micropropagated plantlets produced four times more alkaloids (27.6 ± 3.1 mg/g dry wt) than greenhouse plants. Plantlet roots yielded 3, 4, 8 and the glucoindole alkaloids 3α-dihydrocadambine (9) and dolichantoside (10), the last one not previously found in Uncaria. 相似文献
19.
Yanchan Wei Shiwen Xia Conglin He Wenjuan Xiong Hongmei Xu 《Biotechnology letters》2016,38(5):841-846
Objective
To produce (S)-3-hydroxy-1-(3-(trifluoromethyl)-5,6-dihydro[1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl]-4-(2,4,5-trifluorophenyl)butan-1-one (S)-1 from 4-oxo-4-[3-(trifluoromethyl)-5,6-dihydro [1,2,4]triazolo[4,3-a]pyrazin-7(8H)-yl)-1-(2,4,5-trifluorophenyl)butan-2-one (2) by microbial bioreduction.Results
A new isolate of Pseudomonas pseudoalcaligenes reduced enantioselectively prochiral ketone 2 to chiral alcohol (S)-1. Whole cells of the bacterium were tolerant towards 20 % (v/v) DMSO and 10 g 2/l. Under the optimal conditions, the preparative-scale bioreduction yielded (S)-1 at 90 % yield and >99 % ee. Cells could be re-used with the yield and ee of product being 45 % and >99 %, respectively, after five cycles.Conclusion
Bioreduction using whole cells of P. pseudoalcaligenes is an attractive approach to produce (S)-1, as a chiral intermediate of the anti-diabetic drug, sitagliptin.20.
Shweta Sharma Vishal Sharma Gurpreet Singh Harpreet Kaur Shubham Srivastava Mohan Paul S. Ishar 《Journal of chemical biology》2017,10(1):35-44
A series of novel 2-(chromon-3-yl)-4,5-diphenyl-1H-imidazoles (4a-h) were synthesized by one pot condensation of substituted 3-formylchromones (1a-h), benzil (2) and ammonium acetate (3) in refluxing acetic acid at 110 °C under N2 atmosphere. Allylation of compounds 4a-h with allyl bromide in the presence of fused K2CO3 furnished N-allyl-2-(chromon-3-yl)-4,5-diphenyl-1H-imidazoles (6a-h). The synthesized compounds were characterized spectroscopically and evaluated for in vitro antimicrobial activity against various pathogenic bacterial and fungal strains by disc diffusion method. Compounds bearing electron withdrawing substituents such as bromo (4f) showed significant inhibitory activity against S. cerevisiae (MIC 1.4 μg/ml) and 4g containing chloro substituent, displayed more inhibitory potential against C. albicans (MIC 1.5), as compared to the standard drugs. Compounds 6a and 4c exhibit remarkable inhibitory potential against B. subtilis with MIC 0.98 and 1.23, respectively. The time kill assay for active compound 6a was performed by viable cell count (VCC) method to elucidate the microbicidal nature of 2-(chromon-3-yl)imidazoles. A molecular docking study of most active compounds with target ‘lanosterol 14α-demethylase’ (CYP51) was performed to unravel the mode of antifungal action. 相似文献