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This study was undertaken to analyze the phenolic profiles of 19 propolis samples from Turkey by using a high‐performance thin‐layer chromatographic (HPTLC) method in order to identify their plant origins. Furthermore, their antioxidant and antimicrobial activity profiles were comparatively evaluated. For the appraisal of antioxidant potential, total phenolic (TPC) and total flavonoid contents (TFC) of propolis samples were firstly determined and then their effects on free radicals were evaluated by FRAP, ABTS.+, CUPRAC, DPPH. and HPTLC‐DPPH. methods. Antimicrobial activity of propolis samples against Staphylococcus aureus (ATCC 6538), Pseudomonas aeruginosa (ATCC 15442), Escherichia coli (ATCC 11229) and Candida albicans ATCC 10231 were determined by disc diffusion and broth dilution methods. HPTLC fingerprinting analyses revealed that O‐type (botanical origin from Populus nigra L.) was the primarily available propolis type in Turkey. Moreover, 3‐O‐methylquercetin (3MQ) rich propolis was identified as a new propolis type for the first time. Principal component analysis (PCA) indicated that 3MQ‐type propolis differs from the O‐type. Antioxidant activity studies showed that O‐type of propolis possesses higher antioxidant effect than the other tested propolis types. Quercetin, caffeic acid, caffeic acid phenethyl ester (CAPE) and galangin were determined to contribute significantly to the antioxidant potential of O‐type propolis among others. Propolis extracts exerted moderate antimicrobial activity against the tested microorganisms with MIC values between the ranges of 128–512 μg/mL.  相似文献   
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Abstract

Several protein expression systems can be used to get enzymes in required quantities and study their functions. Incorporating a polyhistidine tag is a beneficial way of getting various enzymes such as FDHs for industrial applications. The NAD+ dependent formate dehydrogenase from Chaetomium thermophilum (CtFDH) can be utilized for interconversion of formate to carbon dioxide coupled with the conversion of NAD+ to NADH. In this study, N-terminal His tagged CtFDH (N-CtFDH) and C-terminal His tagged CtFDH (C-CtFDH) was constructed to learn the effect of His tag location on the activity and kinetic parameters of the enzyme. The solubility of proteins was not affected by tag position, however, an interference on the N-terminal region caused a deterioration in specific activity and the kinetic ability of enzyme. The obtained results indicated that the C-terminus of the enzyme is an appropriate region for tag engineering. The C-CtFDH has an approximately three-fold larger specific activity and two-fold higher catalytic efficiency than N-CtFDH. The results suggest that insertion of a His-tag at the N-terminal or C-terminal end of CtFDH has different effects on the protein and the N-terminal fragment of the protein is crucial for the function of CtFDH.  相似文献   
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In this study rock surfaces of archaeological sites in Antalya were investigated with a focus on black fungi for the first time. Black, meristematic fungi were isolated from surfaces of antique marble monuments in Antalya (Side, Perge, Termessos). Their morphology was characterized, their diversity was documented and the taxonomy and phylogeny of new isolates was clarified based on molecular methods, that is, by sequencing parts of the small ribosomal subunit (18S) and internal transcribed spacer (ITS) regions. From a total of around 250 samples 99 different fungal strains were isolated. In most of 99 strains the rDNA sequencing data and the lack of homologies in “Genbank” gave strong evidence that these strains have to be described as new species/subspecies and/or genera. All of them, however, clustered within the ascomycete orders of Dothideales, Chaetothyriales, and Pleosporales. Field studies show that these organisms cause color changes, black spots, crater shaped lesions as well as chipping and exfoliation of the rock surfaces in Antalya and thus they have to be regarded as a serious threat to the antique cultural heritage in Turkey.  相似文献   
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Capnobotryella is a monotypic genus of melanized fungi based on C. renispora. The purpose of this investigation was to use morphological and molecular genetic techniques to characterize strains of newly discovered species isolated in Turkey on historical marble monuments.  相似文献   
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To date, research has led to the invention of multiple genes and their single nucleotide polymorphisms (SNPs) and environmental factors that influence the prostate cancer (PCa) pathogenesis. Therefore, the genes involved in these pathways are candidates for PCa predisposition. It is thought that polymorphisms of 5alpha-reductase II (SRD5A2) and 17 hydroxylase (CYP17) genes are likely to increase susceptibility. The aim of this study was to investigate the risk association of SRD5A2 and CYP17 gene polymorphisms in the development and progression of PCa in the Turkish population. In this study, 100 PCa patients and 105 healthy controls were studied. SRD5A2 and CYP17 gene polymorphisms were determined by real-time PCR and polymerase chain reaction-restriction length polymorphisms (PCR-RFLP) techniques. First, the AT and TT genotypes of SRD5A2 gene at codon 49 were not observed. Second, there was no significant association between the polymorphisms at codon 89 and the risk of PCa. Third, in the CYP17 gene, the A1A1 genotype is more common (46%) in cases than controls (32.4%). The odds ratios (ORs) of the A1A1 genotype was found at 1.69 (95% confidence interval [CI], 0.77-3.74) compare with the A2A2 genotype. Genotyping results of the SRD5A2 and CYP17 genes were also analyzed in relation to prostate-specific antigen (PSA) levels, Gleason score (GS), and tumor stage, but no statistically significant difference was observed (P > 0.05). Finally, we conclude that there was no evidence of an association between CYP17 (P = 0.134) and SRD5A2 (P = 0.784) polymorphism and PCa risk in the Turkish population.  相似文献   
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D-glycero-D-manno-Heptopyranose 7-phosphate-an intermediate in the biosynthesis of nucleotide-activated heptoses-has been prepared in good overall yield from benzyl 5,6-dideoxy-2,3-O-isopropylidene-alpha-D-lyxo-(Z)-hept-5-enofuranoside by a short-step synthesis. Phosphitylation using the phosphoramidite procedure followed by in situ oxidation afforded the corresponding 7-O-phosphotriester derivative in high yield. Subsequent osmylation proceeded in good diastereoselectivity (4:1) to furnish the D-glycero-D-manno-configured derivative, which was separated from the L-glycero-L-gulo-isomer by chromatography. Hydrogenolysis led to simultaneous removal of the benzyl and isopropylidene groups and afforded the target compound in high yield, which serves as a substrate of bacterial heptose 7-phosphate kinases.  相似文献   
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