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In vitro multiple shoots, root, callus and cell suspension cultures of Withania somnifera exhibited the potentiality to produce pharmacologically active withanolides. Multiple shoots cultures exhibited an increase in withanolide A accumulation compared to shoots of the mother plant. In vitro generated root cultures as well as callus and suspension cultures also produced withanolides albeit at lower levels.  相似文献   
23.
Circular dichroism, topological studies, molecular docking, absorbance, and fluorescence spectral titrations were employed to study the interaction of 4-morpholinopyrimido [4′,5′:4,5] selenolo (2,3-b) quinoline (MPSQ) with DNA. The association constants of MPSQ–DNA interactions were of the order of 104 M?1. Melting temperature, topological, and docking studies confirmed that the mode of interaction was by intercalation with preference to d(GpC)–d(CpG) site of DNA. Cytotoxicity studies showed the MPSQ-induced dose-dependent inhibitory effect on the proliferation of different cancer cells. Colon adenocarcinoma (COLO 205) cells are more sensitive among the cell lines tested, with an IC50 value of 15 μM. Flow cytometry revealed that MPSQ affects the cell cycle progression by arresting at G2M phase. Further, Annexin V staining, mitochondrial membrane potential assay, and caspase-3 activity assay confirmed that MPSQ leads to mitochondria-mediated apoptotic cell death in COLO 205 cells.  相似文献   
24.
This work investigates the potential of metabolic stimulators, firstly to enhance the production of beta-carotene, and later use of inhibitors of lycopene cyclase so as to accumulate lycopene in the fermentation medium. Various non-ionic surfactants, natural oils, stimulators such as amino-acids, tricarboxylic acid cycle (TCA) intermediates, vitamin A and antibiotics were investigated for improved production of beta-carotene using the zygomycete fungus Blakeslea trispora. Span 20 at 0.2% increased the beta-carotene production from 139 mg/l to 318 mg/l. Examination of the mycelial morphology of the B. trispora with span 20 showed a shorter mycelial length, which allowed a well-dispersed growth of B. trispora. Supplementation of the medium with 1000 ppm vitamin A acetate gave highest concentration of beta-carotene (830+/-6 mg/l). Several chemical inhibitors such as imidazole, pyridine, triethylamine, piperidine, and nicotinic acid were then evaluated to block the biosynthesis at lycopene. Piperidine at 500 ppm gave a 7.76-fold improvement, and produced high titers of lycopene (775+/-5 mg/l) in a medium supplemented with vitamin A acetate.  相似文献   
25.
The investigation of three South African Vernonia species afforded minute amounts of five new glaucolides, two monoepoxides and three diepoxides. The structures were elucidated by 1H NMR spectroscopy. The roots of Vernonia sutherlandii contain, in addition to vernonataloide, bergamotene and santalene, minute amounts of the corresponding acetoxy derivatives.  相似文献   
26.
A phosphoramidite chemical synthesis of oligodeoxynucleotides containing a diastereoisomer of (E)-alpha-(N(2)-deoxyguanosinyl)-N-desmethyltamoxifen, a major tamoxifen (TAM)-derived DNA adduct in animal and women treated with TAM, was described. The site-specifically modified oligodeoxynucleotide can be used for mutagenesis, DNA repair, and 3D structural studies and also as standard for quantitative analysis of TAM-DNA adducts in animal and human.  相似文献   
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Accurate prediction of complex traits based on whole-genome data is a computational problem of paramount importance, particularly to plant and animal breeders. However, the number of genetic markers is typically orders of magnitude larger than the number of samples (p >> n), amongst other challenges. We assessed the effectiveness of a diverse set of state-of-the-art methods on publicly accessible real data. The most surprising finding was that approaches with feature selection performed better than others on average, in contrast to the expectation in the community that variable selection is mostly ineffective, i.e. that it does not improve accuracy of prediction, in spite of p >> n. We observed superior performance despite a somewhat simplistic approach to variable selection, possibly suggesting an inherent robustness. This bodes well in general since the variable selection methods usually improve interpretability without loss of prediction power. Apart from identifying a set of benchmark data sets (including one simulated data), we also discuss the performance analysis for each data set in terms of the input characteristics.  相似文献   
29.
The antipsychotic drug prochlorperazine was screened in vitro for possible antimicrobial property against 157 strains of bacteria, belonging to gram positive and gram negative genera. The minimum inhibitory concentration (MIC) of prochlorperazine was determined by agar dilution method, which ranged from 25 to 200 microg/ml with respect to most of the strains. Based on such findings, a further study was undertaken to determine whether the efficacy of this drug could be enhanced in the presence of an antihistaminic agent methdilazine, reported to have remarkable antimicrobial action. Four bacterial strains, sensitive to prochlorperazine as well as to three antibacterial chemotherapeutics, viz., methdilazine, fluphenazine and thioridazine were chosen. Disc diffusion tests with prochlorperazine and methdilazine revealed marked synergism between the combination, compared to their individual effects. The synergism was found to be statistically significant (p<0.01). To assess the degree of synergism, the checkerboard analysis was performed. The FIC index of this combination turned out to be 0.37, which confirmed synergism. Therefore, this synergistic drug combination might open a new therapeutic approach to combat drug-resistance in bacterial infections.  相似文献   
30.
Russian Journal of Bioorganic Chemistry - Discovery towards the potent antimicrobial agents is indispensable for the treatment of infections caused by resistant microbes. Thus, we prepared a novel...  相似文献   
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