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Betulinic and oleanolic acids isolated from Forsythia suspensa
Vahl inhibit urease activity of Helicobacter pylori 总被引:1,自引:0,他引:1
Seung-Jung Shin Chan-El Park Nam-In Baek In Sik Chung Chang-Ho Park 《Biotechnology and Bioprocess Engineering》2009,14(2):140-145
Sixteen medicinal herbs were selected from a database on traditional herbal materials as well as literature on Korean plant
resources. Then ethanol (70%, v/v) extracts of these herbs were tested for inhibition of the urease activity of Helicobacter pylori. The urease activity of H. pylori was strongly (82%) inhibited by extract of Forsythia suspensa
Vahl. Active compounds in extract of Forsythia suspensa
Vahl were first separated by batch mode solvent extraction, followed by purification by silica gel and octadecyl silica gel column
chromatography using solvents of different polarity. According to NMR analysis of the last chromatographic fraction, we identified
the presence of betulinic acid and oleanolic acid, which are known to have anti-inflammatory, anti-cancer, and anti-HIV viral
activities. 相似文献
4.
Inorganic cofactors (Mn, Ca2+ and Cl-) are essential for oxidation of H2O to O2 by Photosystem II. The Mn reductants NH2OH and its N-methyl derivatives have been employed as probes to further examine the interactions between these species and Mn at the active site of H2O oxidation. Results of these studies show that the size of a hydroxylamine derivative regulates its ability to inactivate O2 evolution activity, and that this size-dependent inhibition behavior arises from the protein structure of Photosystem II. A set of anions (Cl-, F- and SO4
2-) is able to slow NH2OH and CH3NHOH inactivation of intact Photosystem II membranes by exerting a stabilizing influence on the extrinsic 23 and 17 kDa polypeptides. In contrast to this non-specific anion effect, only Cl- is capable of attenuating CH3NHOH and (CH3)2NOH inhibition in salt-washed preparations lacking the 23 and 17 kDa polypeptides. However, Cl- fails to protect against NH2OH inhibition in salt-washed membranes. These results indicate that the attack by NH2OH and its N-methyl derivatives on Mn occurs at different sites in the O2-evolving complex. The small reductant NH2OH acts at a Cl--insensitive site whereas the inhibitions by CH3NHOH and (CH3)2NOH involve a site that is Cl- sensitive. These findings are consistent with earlier studies showing that the size of primary amines controls the Cl- sensitivity of their binding to Mn in the O2-evolving complex.Abbreviation MES
4-morpholinoethanesulfonic acid
- PS II
Photosystem II 相似文献
5.
To better understand the patterns of variability and distributions ofHemerocallis in Korea, 53 locations were visited and measurements of 19 morphological and phenological characters were taken on plants
directly from their natural habitats. For morphometric analysis, 10 plants from each of 34 populations and five herbarium
specimens ofH. middendorffii were used and the data from 12 quantitative characters was analyzed using univariate analysis. Except the littoral populations
of Cheju, Hong, Taehuksan, and Sohuksan Islands (H. hongdoensis M. Chung & S. Kang), three peninsular KoreanHemerocallis species can be recognized mainly in South Korea:H. hakuunensis Nakai (=H. micrantha Nakai, growing on southern, central, and northwestern Korea);H. thunbergii Baker (=H. coreana Nakai, found on southeastern and central Korea); andH. middendorffii Tr. et Mey. (central and northeastern Korea). Morphological and phenological features contributing to recognition of the
three groups were; color of perianth, shape of roots, shape of inflorescence, flowering time, odor, length of inflorescence,
width of the lowest bracts, length of perianth tube enclosing a ovary, width of the inner perianth lobes. Natural hybridization
seems to be rare in KoreanHemerocallis. It appears that the KoreanHemerocallis species are relatively well characterized by their distribution patterns, phenology, and habitats compared with the JapaneseHemerocallis species. 相似文献
6.
Hyuk-Sung Kwon Eunyong Chung Junse Oh Chang-Ha Lee Ik-Sung Ahn 《Biotechnology and Bioprocess Engineering》2008,13(1):108-114
Manganese peroxidase (MnP) is a key enzyme involved in the lignolysis of white-rot fungi. The purpose of this study is to
investigate the effect of immobilization and culture conditions on MnP production in cultures of Phanerochaete chrysosporium grown on polyurethane foam. Higher concentrations of foam and lower levels of spore inoculums resulted in the formation of
scattered mycelial pellets, increased autolysis of chlamydospore-like cells (a reservoir of MnP), and a higher activity of
MnP. Even though MnP was a secondary metabolite, the addition of 5 times more glucose and diammonium tartrate, as carbon and
nitrogen sources, resulted in a 4 fold increase in the dry cell mass. However, MnP activity decreased under these conditions
to less than half, due to the formation of increasingly dense pellets and the inhibited lysis of chlamydospore-like cells. 相似文献
7.
Sung H Chul Han K Chul Kim J Wan Oh K Su Yoo H Tae Hong J Bok Chung Y Lee CK Lee KS Song S 《FEMS yeast research》2005,5(10):943-950
Functional analysis of genes from Saccharomyces cerevisiae has been the major goal after determination of genome sequences. Even though several tools for molecular-genetic analyses have been developed, only a limited number of reliable genetic tools are available to support functional assay at protein level. Epitope tagging is a powerful tool for detecting, purifying, and functional studying of proteins. But systematic tagging systems developed with integration vectors are not available. Here, we have constructed a set of integration vectors allowing a translational fusion of interested proteins to the four different epitope tags (HA, Myc, Flag, and GFP). To confirm function and expression of C-terminal-tagged proteins, we used Cdc11, a component of the septin filament that encircles the mother bud neck and consists of five major proteins: Cdc3, Cdc10, Cdc11, Cdc12, and Sep7. The tagged version of Cdc11 expressed under its endogenous promoter was found to be physiologically functional, as evidenced by localization at the neck and suppression of the growth defect associated with the temperature-sensitive mutation of cdc11-6. The expressed proteins were efficiently detected with antibodies against Cdc11 or the epitopes. When immunoprecipitated with anti-Myc antibody, each septin protein tagged with Myc was effectively copurified with other septin components, indicating formation of a stable septin complex. Because the modules of the tags were located under the same array of eighteen restriction sites on integration vectors containing four different markers (HIS3, TRP1, LEU2, or URA3), this tagging system provides efficient multiple tagging and stable expression of a gene of interest. 相似文献
8.
9.
Chul-Hong Park Byung Yeoup Chung Seung Sik Lee Hyoung-Woo Bai Jae Young Cho Cheorun Jo Tae Hoon Kim 《Bioorganic & medicinal chemistry letters》2013,23(4):1099-1103
Radiolytic transformation of the isoflavonoid rotenone (1) with γ-irradiation afforded two new degraded products, rotenoisins A (2) and (3). The structures of the two new rotenone derivatives were elucidated on the basis of spectroscopic methods. The new products 2 and 3 exhibited significantly enhanced inhibitory activities against pancreatic lipase and adipocyte differentiation in 3T3-L1 cells when compared to parent rotenone. 相似文献
10.
Y. Chu E. Yang J. M. Schinaman J. S. Chahda R. Sousa‐Neves 《Evolution; international journal of organic evolution》2013,67(8):2335-2347
Courtship is an elaborate behavior that conveys information about the identity of animal species and suitability of individual males as mates. In Drosophila, there is extensive evidence that females are capable of evaluating and comparing male courtships, and accepting or rejecting males as mates. These relatively simple responses minimize random sexual encounters involving subpar conspecific males and heterospecific males, and over generations can potentially select novel physical and behavioral traits. Despite its evolutionary and behavioral significance, little is still known about the genes involved in mating choice and how choices for novel males and females arise during evolution. Drosophila simulans and Drosophila sechellia are two recently diverged species of Drosophila in which females have a preference for conspecific males. Here we analyzed a total of 1748 F2 hybrid females between these two species and found a small number of dominant genes controlling the preference for D. simulans males. We also mapped two redundant X‐linked loci of mating choice, Macho‐XA and Macho‐XB, and show that neither one is required for female attractiveness. Together, our results reveal part of the genetic architecture that allows D. simulans females to recognize, mate, and successfully generate progenies with D. simulans males. 相似文献