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1.
Mannitol dehydrogenase (mannitol: NADP+ 2-oxidoreductase: EC 1.1.1.138) was isolated from Agaricus bisporus by fractionation with protamine sulphate and (NH4)2SO4, followed by chromatography on DEAE-Sephadex, then by affinity and gel chromatography. The products of enzyme reaction were identified by GLC and TLC. Km, optimum pH, MW and pI of the enzyme as well as the influence of temperature, ions and inhibitors on enzymic activity were determined. In the sugar reducing reaction, the enzyme was specific for fructose but, in the reverse direction, some structurally related polyols could substitute for mannitol. The enzyme was very sensitive to alterations in the NADP+/NADPH ratio. The results are discussed in relation to the possible role of mannitol dehydrogenase in fungal metabolism. 相似文献
2.
Seulah Lee Dahae Lee Joo Chan Lee Ki Sung Kang Rhim Ryoo Hyun‐Ju Park Ki Hyun Kim 《化学与生物多样性》2018,15(9)
Calvatia species, generally known as puffball mushrooms, are used both as sources of food and as traditional medicine. Among the Calvatia genus, Calvatia nipponica (Agaricaceae) is one of the rarest species. Using bioassay‐guided fractionation based on anti‐inflammatory effects, five alkaloids ( 1 – 5 ), two phenolics ( 6 and 7 ), and a fatty acid methyl ester ( 8 ) were isolated from the fruiting bodies of C. nipponica. Compound 8 was identified from C. nipponica for the first time, and all isolates ( 1 – 8 ) were tested for inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)‐stimulated RAW264.7 macrophages. Compound 7 showed mild inhibition while compound 8 significantly inhibited NO production with an IC50 value of 27.50 ± 0.08 μm . The mechanism of NO inhibition of compound 7 was simulated by molecular docking analysis against nitric oxide synthase (iNOS), which revealed the interactions of 7 with the key amino acid residue and the heme in the active site. With the most potent inhibition against LPS‐induced inflammation, compound 8 was further investigated with respect to its mechanism of action, and the activity was found to be mediated through the inhibition of iNOS and COX‐2 expression. 相似文献
3.
Two blazeispirane derivatives including blazeispirols G and I were isolated from the cultured mycelia of the fungus Agaricus blazei Murill and were established to be (20S, 22S, 23R, 24S)-14 beta,22: 22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9-triene-11 alpha,23-diol and (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9,11-tetraene-23,28-diol by comparison of extensive 1D and 2D NMR spectral data with that of blazeispirol A. Furthermore, four blazeispirol derivatives blazeispirols, U, V, V(1) and Z(1) were isolated form the same source described above. Their structures were determined to be (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-23-hydroxyergosta-4,6,8,11-tetraen-3-one, (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-6 alpha,7 alpha,23-trihydroxyergosta-4,8,11-trien-3-one, (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-6 beta,7 alpha,23-trihydroxyergosta-4,8,11-trien-3-one and (20S, 22S, 23R, 24S)-14 beta,22:22,25-diepoxy-23-hydroxy-4,5-seco-ergosta-6,8-diene-3,5-dione by extensive 1 D and 2D NMR spectral data. 相似文献
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5.
Four new des-A-ergostane derivatives including blazeispirols B, C, E and F were isolated from the cultured mycelia of fungus Agaricus blazei Murill and were established to be (20S, 22R, 23R, 24S)-14beta,22: 22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9,11-tetraen-23-ol; (20S, 22S, 23R, 24S)-14beta,22: 22,25-diepoxy-5-methoxy-des-A-ergosta-5,7,9-trien-23-ol; (20S, 22S, 23R, 24S)-14beta, 22: 22, 25-diepoxy-5-methoxy-des-A-ergosta-5,7,9,11-tetraene-19,23-diol and (20S, 22S, 23R, 24S)-14beta,22: 22,25-diepoxy-des-A-ergosta-5,7,9-triene-5,23-diol by comparison of extensive 1D and 2D NMR spectral data with that of blazeispirol A. 相似文献
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7.
Seulah Lee Jun Yeon Park Dahae Lee Soonja Seok Yeon Jung Kwon Tae Su Jang Ki Sung Kang Ki Hyun Kim 《Bioorganic & medicinal chemistry letters》2017,27(17):4122-4127
Calvatia species, also known as puffball mushrooms, are common sources of food worldwide. Calvatia nipponica (Agaricaceae) is one of the most rare species in the Calvatia genus. It was first validated in 2008. Due to its scarcity, C. nipponica has never been chemically investigated. Its recent discovery in Korea allowed to conduct this study, and using bioactivity-guided fractionation for antiangiogenic activity, chemical investigation of the MeOH extract of the fruiting bodies of C. nipponica led to the isolation of five alkaloids (1–5) and two phenolic compounds (6–7). This is the first study to report the chemical investigation of C. nipponica, and compound 1 was previously reported as chemically synthesized only until our report of its isolation and identification from natural sources. The structure of 1 was determined by spectroscopic analysis by 1D and 2D NMR spectra and HR-MS. All compounds (1–7) were tested for inhibition of angiogenesis using human umbilical vein endothelial cells (HUVECs). Compounds 2, 4 and 5 significantly inhibited the promotion of angiogenesis in HUVECs. Compound 5 showed the most potent inhibition via downregulation of VEGF, p38 and ERK signaling pathways. These results suggested that the rare mushroom C. nipponica might be beneficial in antiangiogenesis therapy for cancer treatment. 相似文献
8.
The following sterols have been isolated from the fungi, Phycomyces blakesleeanus and Agaricus campestris: ergosterol, lanosterol, 24-methylene-24,25-dihydrolanosterol and episterol. 4,4-Dimethyl-5α-ergosta-8.24(28)-dien-3β-ol and 4α-methyl-5α-ergosta-8,24(28)-dien-3β-ol have been tentatively identified. Evidence for the incorporation of label from l-methionine-[methyl-14C] into some of these sterols in P. blakesleeanus has been obtained. The significance of these sterols in ergosterol biosynthesis is discussed. 相似文献
9.
Hydrogen peroxide (H2O2) inactivates mushroom tyrosinase in a biphasic manner, with the rate being faster in the first phase than in the second one. The inactivation of the enzyme is dependent on H2O2 concentration (in the range of 0.05–5.0 mM), but independent of the pH (in the range of 4.5–8.0). The rate of inactivation of mushroom tyrosinase by H2O2 is faster under anaerobic conditions (nitrogen) than under aerobic ones (air). Substrate analogues such as L-mimosine, L-phenylalanine, p-fluorophenylalanine and sodium benzoate protect the enzyme against inactivation by H2O2. Copper chelators such as tropolone and sodium azide also protect the enzyme. Under identical conditions, apotyrosinase is not inactivated by H2O2, unlike holotyrosinase. The inactivation of mushroom tyrosinase is not accelerated by an OH?dot generating system (Fe2+-EDTA-H2O2) nor is it protected by OHdot scavengers such as mannitol, urate, sodium formate and histidine. Exhaustive dialysis or incubation with catalase does not restore the activity of H2O2-inactivated enzyme. The data suggest that Cu2+ at the active site of mushroom tyrosinase is essential for the inactivation by H2O2. The inactivation does not occur via the OHdot radical in the bulk phase but probably via an enzyme-bound OHdot. 相似文献
10.
1-Formyl-4-methyl-7-isopropyl azulene (11,12-dihydro-lactaroviolin) was characterized from Lactarius deterrimus together with other known compounds. 相似文献