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1.
Akira Fujinami Nobumasa Tottori Toshiro Kato Nobuyuki Kameda 《Bioscience, biotechnology, and biochemistry》2013,77(9):1623-1630
The structure-activity relationships of 3-(3′,5′-dichlorophenyl)imidazolidine-2,4-dione derivatives were investigated by the agar dilution method using Sclerotinia sclerotiorum as a test microbe. Several compounds were tested for antimicrobial spectrum in vitro with other pathogenic microbes and for foliage protective activity in green house tests with rice sheath blight, rice brown spot, damping-off of cucumber and kidney bean stem rot. It was found that the antimicrobial activity was enhanced when the 1-position of imidazolidine ring was substituted by an alkyl group but was reduced when the 5-position was substituted by alkyl groups. Generally, 3-(3′,5′-dichlorophenyl)imidazolidine-2,4-dione derivatives were active against Scierotiniaceae, Corticiaceae, Dematiaceae, Polystigmataceae or Pleosporaceae. In green house tests, some of these compounds showed high protective activity against rice sheath blight, rice brown spot, damping-off of cucumber and kidney bean stem rot. Results of the green house tests on the above mentioned diseases correlate well with those of in vitro tests except in the case of kidney bean stem rot. 相似文献
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Ethylene-bis-nitrouretharie (EBNU), NN'-dinitroethylene urea,and ethylene dinitramine were found to increase the growth ofsome broad-leaved plants (peas, broad beans, and tomatoes),grasses and cereals. Other plants were unaffected, and furthermoreexperiments with peas showed pronounced differences betweenthe responses of several varieties of one species. Treatmentof dicotyle dons increased the growth of the stem by promotionof internode extension possibly based on enhanced cell growth.Leaf areas and dry weights were less affected. The leaf lengthof cereals was increased, and small improvements in the dry-matteryield of grass were obtained in field experiments. Stimulatedplants remained relatively normal in appearance, and in somecases the effect of a single treatment with EBNU persisted throughoutthe entire vegetative development. In some respects the effectsof EBNU resembled those of gibberellic acid, but important differenceswere found when the two chemicals were applied to a number ofpea varieties, and when internode growth-rates were measured.EBNU and related chemicals stimulated the later stages of internodegrowth, high rates prolonging the period over which the internodesextended. It is suggested that they may antagonize processesleading to the cessation of cell growth. Pot and field trials suggest that the activity of EBNU is notsufficiently great to make it useful in agricultural practice.It is also known to be dermatitic, and its relatives are explosive. 相似文献
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?. Drobnica M. Zemanová P. Nemec K. Anto? P. Kristián A. ?tullerová V. Knoppová P. Nemec Jr. 《Applied and environmental microbiology》1967,15(4):701-709
Data are presented concerning the antifungal activity of 11 natural isothiocyanates and 27 synthetized analogues in Aspergillus niger, Penicillium cyclopium, and Rhizopus oryzae, as well as in 13 additional saprophytic and parasitic fungi. A remarkable antifungal activity was observed in some analogues of benzylisothiocyanate and β-phenylethylisothiocyanate. The latter-mentioned compounds have not been described previously. In the group of benzylisothiocyanates, a correlation, which was inversely proportional, was detected between ed100 values for A. niger and R. oryzae and the corresponding molar solubilities of compounds in water. In contradistinction, no relationship was observed between antifungal activity and chemical reactivity of investigated derivatives. 相似文献
5.
V. A. Efimov A. A. Buryakova M. V. Choob O. G. Chakhmakhcheva 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1393-1396
Abstract The synthesis of a set of novel chimeric oligomers representing PNA and phosphono-PNA analogues has been accomplished, and their binding affinity to complementary DNA and RNA strands was evaluated. 相似文献
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N. V. Amirkhanov N. V. Tikunova D. V. Pyshnyi 《Russian Journal of Bioorganic Chemistry》2018,44(5):492-503
Comparative antimicrobial properties of three artificial cationic synthetic antimicrobial peptides (SAMP): (RAhaR)4AhaβA (where R is Arg, Aha is 6-aminohexanoic acid, βA is beta-alanine), (KFF)3K and R9F2 with various amphiphilic properties have been studied relative to pathogenic strains of microorganisms: Gram-negative bacteria Pseudomonas aeruginosa, Escherichia coli, Proteus mirabilis, and Salmonella enterica, Gram-positive bacteria Staphylococcus aureus, and pathogenic yeast fungus Candida albicans. The selectivity index (SI) values of the peptide preparations were calculated as the ratio of the 50% cytotoxic concentration (TC50) towards eukaryotic host cells to the MIC50 values of the testing antimicrobial peptides. The studied SAMPs appeared to be the most active against the pathogenic yeast fungus C. albicans and the bacterial strains St. aureus and P. aeruginosa. The SI values in these cases exceed 40. Some assumed molecular interactions of the studied SAMPs on the microbial cells have been considered, and possible pathways to increase their antimicrobial activity have been suggested. The proposed SAMPs can serve as a basis for the design and synthesis of new promising synthetic antimicrobial agents. 相似文献
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天然酚类色素的研究与应用进展 总被引:1,自引:0,他引:1
植物花色素的研究已经非常广泛和深入,多酚类化合物作为重要的天然食用色素越来越受到人们的重视.本文结合近年来的最新研究成果,从酚类色素的种类与结构、理化性质、提纯与鉴定、稳定性及影响因素、生物功能和应用价值等方面进行了综述,并对酚类的研究热点进行了展望,对人们全面认识和开发利用酚类色素具有一定的参考文献:价值. 相似文献
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J. H. Arango A. Geer J. Rodriguez P. E. Young P. Scheiner 《Nucleosides, nucleotides & nucleic acids》2013,32(7):773-784
Abstract Cis and trans-1-(4-hydroxy-2-cyclohexenyl)- and 1-(2-hydroxy-5-cyclohexenyl) thymines were obtained by stereospecific routes. Oxidation of the 1, 4-products afforded 1-(4-oxo-2-cyclohexenyl)thymine, the carbocyclic analog of a reportedly antiviral ketopyranosyl nucleoside. Exclusive 1, 6-conjugate addition occurred with heterocyclic bases and methyl 1, 3-cyclohexadiene-1-carboxylate. Reduction of the thymine adduct gave 1-(4-hydroxymethyl1-3-cyclohexenyl)thymine. Michael-type addition provided a direct route to 3-oxocycloalkyl nucleosides, and lactone nucleosides resulted from addition of bases to α-methylene-γ-butyrolactone. Anti-HIV screening revealed no activity for the new compounds. 相似文献
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Antifungal Activity of Isothiocyanates and Related Compounds: II. Mononuclear Aromatic Isothiocyanates 下载免费PDF全文
Antifungal activity on Aspergillus niger, Penicillium cyclopium, and Rhizopus oryzae, as well as on additional saprophytic and parasitic fungi, was determined in 57 substituted derivatives of phenylisothiocyanate. Most of the investigated compounds displayed rather equal activity against the three mentioned fungi, in contradistinction to the analogues of natural benzyl- and beta-phenylethylisothiocyanate with their characteristic low activity against R. oryzae. Differences occurred in the type of activity of compounds in which the -NCS group is directly bound on the aromatic moiety, as compared with those compounds in which this group is bound to the aliphatic radical or to the aromatic moiety indirectly by means of the methyl group or by a longer aliphatic chain. The results obtained confirm the negative influence of ionized substituents on the aromatic moiety, i.e., of -COOH, -CH(2)- COOH, and -SO(3)H groups, as well as of substituents which cause an extreme increase in reactivity of the -NCS group resulting in a high instability of the entire isothiocyanate molecule. 相似文献
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Takayuki Okabe Kazuyuki Maekawa Eiji Taniguchi 《Bioscience, biotechnology, and biochemistry》2013,77(5):1197-1201
A homologous transformation system was developed using the endogenous ATP-sulfurylase gene, AasC, as a selectable marker in Aspergillus aculeatus. Spontaneous mutation was proved to be beneficial in isolating AasC-deficient mutants. Molecular analysis of sC + transformants revealed that the frequency of single copy integration at ATP-sulfurylase locus was more than 40%. 相似文献
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Eggshell Bacterial Load Is Related to Antimicrobial Properties of Feathers Lining Barn Swallow Nests
Juan Manuel Peralta-Sánchez Juan José Soler Antonio Manuel Martín-Platero Rob Knight Manuel Martínez-Bueno Anders Pape Møller 《Microbial ecology》2014,67(2):480-487
The use of feathers to line bird’s nests has traditionally been interpreted as having a thermoregulatory function. Feather-degrading bacteria growing on feathers lining nests may have antimicrobial properties, which may provide an additional benefit to lining nests with feathers. We test the hypothesis that the production of antimicrobial substances by feather bacteria affects the microbiological environment of the nest, and therefore the bacterial density on eggshells and, indirectly, hatching success. These effects would be expected to differ between nests lined with pigmented and white feathers, because bacteria grow differently on feathers of different colors. We experimentally manipulated the composition of pigmented and unpigmented feathers in nests of the barn swallow (Hirundo rustica) and studied the antimicrobial properties against the keratin-degrading bacterium Bacillus licheniformis of bacteria isolated from feathers of each color. Analyzed feathers were collected at the end of the incubation period, and antimicrobial activity was defined as the proportion of bacteria from the feathers that produce antibacterial substances effective against B. licheniformis. Our experimental manipulation affected antimicrobial activity, which was higher in nests with only white feathers at the beginning of incubation. Moreover, white feathers showed higher antimicrobial activity than black ones. Interestingly, antimicrobial activity in feathers of one of the colors correlated negatively with bacterial density on feather of the opposite color. Finally, antimicrobial activity of white feathers was negatively related to eggshell bacterial load. These results suggest that antimicrobial properties of feathers in general and of white feathers in particular affect the bacterial environment in nests. This environment in turn affects the bacterial load on eggshells, which may affect hatching success. 相似文献
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Abstract Acyclic nucleotide analogues bearing amino- and N-substituted amino groups in the side chain were prepared by alkylation of the bases with corresponding oxiranes and subsequent introduction of phosphonomethyl ether function. Novel enantiomeric synthons for the preparation of HPMP-compounds were prepared from a common intermediate and applied to syntheses of novel compounds (e.g. 8-azaguanine derivatives). 相似文献
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Satoru Oka 《Bioscience, biotechnology, and biochemistry》2013,77(8):500-514
It has been observed that, in the culture medium, the toxicity of p-benzoquinone on bakers’ yeast decreases with time, and the decreasing process was examined from the view point of chemical reaction of quinone with the component of the medium.As a result, it was shown that quinone concentration decreases by its 1,4-addition reaction with amino radicals of the component of the medium, and it was concluded that the inhibiting effect of quinone on the yeast growth is determined by the velocity of death of the yeast by the toxicity of quinone and that of inactivation of the toxicity by the addition reaction. 相似文献
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Variation in Polyphenolic Profiles,Antioxidant and Antimicrobial Activity of Different Achillea Species as Natural Sources of Antiglycative Compounds 下载免费PDF全文
A comparative study was carried out on the methanolic extracts from six Achillea species and the examined polyphenols from these plants on the formation of advanced glycation end‐products (AGE) in vitro. A. pachycephala which was richer in flavonoids (15 mg quercetin/g W) and phenolics (111.10 mg tannic acid/g DW) with substantial antioxidant activity (IC50 = 365.5 μg/ml) presented strong anti‐AGE properties. Chlorogenic acid, luteolin, quercetin and caffeic acid were identified as the major polyphenols in the extracts by HPLC. In general, polyphenolic content follows the order of A. pachycephalla > A. nobilis > A. filipendulina > A. santolina > A. aucheri > A. millefolium. Most extracts exhibited marked anti‐AGE ability in the bovine serum albumin (BSA)/methylglyoxal (MG) system, though A. pachycephala showed the highest potential. The formation of AGEs was assessed by monitoring the production of fluorescent products and circular dichroism (CD) spectroscopy. Diminution in free radical production (assessed by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) assays) is discussed as potential mechanism for delay or reduced AGE. The results demonstrate the antiglycative, antioxidant and antimicrobial potential of Achillea species which can be attributed to polyphenols content and the effectiveness on generation of AGEs, thus Achillea species can be considered as natural sources for slowing down glycation related diseases. 相似文献
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《Bioscience, biotechnology, and biochemistry》2013,77(6):1444-1446
Bisphenol A was oxidized to monoquinone and bisquinone derivatives by Fremy’s salt, a radical oxidant, though salcomine and alkali did not catalyze the oxidation by molecular oxygen. Bisphenol A, bisphenol B, and 3,4'-(1-methylethylidene)bisphenol were converted to their monoquinone derivatives in the presence of tyrosinase at 25°C at pH 6.5, but not to the bisquinone derivatives under these conditions. 相似文献
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Akira Hasegawa Daikichi Nishimura Takashi Kurokawa Minoru Nakajima 《Bioscience, biotechnology, and biochemistry》2013,77(10):1773-1776
Paromamine and its related compounds were synthesized by a modified Königs-Knorr reaction of 3,4,6-tri-O-acetyl-2-(2′,4′-dinitroanilno)-α-d-glucopyranosyl bromide with isopropylidene derivatives of 2-deoxystreptamine, streptamine and dihydroconduramine F–4. The condensed products were isolated as their poly N-acetyl derivatives and proved to have α-configuration by PMR spectroscopy in D2O. 相似文献
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Biocidal Activities of Glutaraldehyde and Related Compounds 总被引:10,自引:10,他引:0
S ummary . Glutaraldehyde in 2% aqueous alkaline solution is rapidly bactericidal and sporicidal, killing 99.99% of the spores of Bacillus anthracis and Clostridium tetani in 15 and 30 min, respectively. It exhibits some degree of tuberculocidal activity, but it appears to be inferior to several other disinfectants when challenged with a large inoculum. Fungicidal action has been demonstrated but not assessed quantitatively. Evidence is presented to show that biocidal activity depends on the availability of two free aldehyde groups in the molecule. 相似文献
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M. N. Galbraith D. H. S. Horn Shô Itô M. Kodama J. M. Sasse 《Bioscience, biotechnology, and biochemistry》2013,77(13):2393-2396
The plant-growth inhibitory activities of a number of compounds related to the podolactones were determined using a pea-stem growth system. Some conclusions regarding the effects of structure on activity are presented. 相似文献
20.
Satoru Oka 《Bioscience, biotechnology, and biochemistry》2013,77(6):387-398
The qualitative change and quantitative change of p-benzoquinone were followed in yeast suspension to obtain the information on the mechanism of the antimicrobial effect of quinone compounds. When the quinone concentration was below 0.16 mM, the quinone was found to be continuously reduced to hydroquinone by the yeast in the presence of energy substrate, whereas the concentration exceeded 0.16 mM, the reduction ability was rapidly destroyed even in the presence of energy substrate.The critical concentration for destruction of the reduction ability was considered to be related to the toxic effect of the quinone on the yeast. 相似文献