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1.
A New Bibenzyl Glycoside from Dendrobium moniliforme   总被引:1,自引:0,他引:1  
A new bibenzyl glycoside has been isolated from the stems of Dendrobium moniliforme (L.) Sw.(Orchidaceas).Its structure has been identified on the basis of spectroscopic and chemical methods.  相似文献   
2.
A new Dendrobine-Type Alkaloid from Dendrobium nobile   总被引:1,自引:0,他引:1  
A new dendrobine-type alkaloid has been isolated from stems of Dendrobium nobile lindl.Its structure has been identified on the basis of spectroscopic method.  相似文献   
3.
Dendrobium officinale is an important medicinal plant in traditional Chinese medicine. The consumption of D. officinale has increased rapidly in recent years due to the health awareness among Chinese people. The present study aimed to determine trace elements levels in 42 D. officinale samples and to utilize the elemental data for identifying the cultivation technique. Eighteen trace elements (B, V, Cr, As, Mn, Fe, Mo, Cu, Zn, Se, Sr, Sn, Ti, Al, Co, As Pb, Cd, and Bi) were determined by inductively coupled plasma–mass spectrometry. Of the 11 essential elements, the mean concentrations ranged from 30.6?µg?kg?1 (Mo) in D. officinale with greenhouse cultivation to 161?mg?kg?1 (Fe) in D. officinale with rock cultivation, and the contributions of Mn may exceed the dietary reference intake value by the uptake of 20?g of D. officinale. Of the seven toxic elements, the mean concentrations ranged from 3.29?µg?kg?1 (Bi) in the D. officinale with greenhouse cultivation to 342?mg?kg?1 (Al) in the D. officinale with rock cultivation, and the contributions of Al may exceed the provisional tolerable daily intake value by the uptake of 20?g of D. officinale. The concentrations of seven metals (Bi, Pb, Fe, Al, Cr, As, and Mo) were utilized to identify the cultivation technique of the analyzed D. officinale samples through linear discriminant analysis.  相似文献   
4.
A new method of extracting essential oils from dried plant materials has been studied. By adding a microwave-absorption medium (MAM) to a reactor, solvent-free microwave extraction (SFME) was improved and can be used to extract essential oils from dried plant material without pretreatment. With a microwave irradiation power of 85 W it took only approximately 30 min to extract the essential oils completely. The whole extraction process is simple, rapid, and economical. Three types of MAM, iron carbonyl powder (ICP), graphite powder (GP), and activated carbon powder (ACP), and two types of dried plant material, Illicium verum Hook. f. and Zingiber officinale Rosc., were studied. The results were compared with those obtained by use of conventional SFME, microwave-assisted hydrodistillation (MAHD), and conventional hydrodistillation (HD), and the conclusion drawn was that improved SFME was a feasible means of extracting essential oils from dried plant materials, because there were few differences between the composition of the essential oils extracted by improved SFME and by the other methods.  相似文献   
5.
6.
A water-soluble polysaccharide TC-DHPA4 with a molecular weight of 8.0 × 105 Da was isolated from tissue-cultured Dendrobium huoshanense by anion exchange and gel permeation chromatography. Monosaccharide analysis revealed that the homogeneous polysaccharide was made up of rhamnose, arabinose, mannose, glucose, galactose and glucuronic acid with a molar ratio of 1.28:1:1.67:4.71:10.43:1.42. The sugar residue sequence analysis based on the GC-MS files and NMR spectra indicated that the backbone of TC-DHPA4 consisted of the repeated units:→6)-β-Galp-(1→6)-β-Galp-(1→4)-β-GlcpA-(1→6)-β-Glcp-(1→6)-β-Glcp-(→. The sugar residue sequences β-Glcp-(1→)-α-Rhap-(1→3)-β-Galp-(1→, β-Glcp-(1→4)-α-Rhap-(1→3)-β-Galp-(1→, β-Galp-(1→6)-β-Manp-(1→3)-β-Galp-(1→, and α-l-Araf-(1→2)-β-Manp-(1→3)-β-Galp-(1→ were identified as the branches attached to the C-3 position of (1→6)-linked galactose in the backbone.  相似文献   
7.
Two new compounds from Zingiber officinale   总被引:1,自引:0,他引:1  
A new cyclic diarylheptanoid,1,5-epoxy-3-hydroxy-1-(3-methoxy-4,5-dihydroxyphenyl)-7-(4-hydroxyphenyl)-heptane (1),as well as a new monoterpene,10-O-β-D-glucopyranosyl-hydroxy cineole (2) were isolated from the rhizomes of Zingiber officinale. The structures of compounds 1 and 2 were established based on their spectral data.In addition,the antioxidant activities of these compounds were also measured.  相似文献   
8.
It is generally believed that fresh Dendrobium officinale (FDO) has more significant pharmacological activity than dried Dendrobium officinale (DDO); however, the difference has not been clearly shown. Our study compared their antioxidant properties both in vitro and in vivo, and the molecular weight arrangement and monosaccharide composition of the fresh Dendrobium officinale polysaccharides (FDOPs) and the dried Dendrobium officinale polysaccharides (DDOPs) were analyzed by HPLC-GPC and GC-MS. The results showed that the FDO and its polysaccharides had more significant effects on scavenging DPPH, ABTS, and hydroxyl radicals than the DDO. In addition, both the FDO and DDO significantly reduced lipid peroxidation levels and increased the SOD, T-AOC, CAT, and GSH levels in mice with acute liver damage caused by CCl4, while the FDO and its polysaccharides were more effective. Histopathological analysis further verified the protective effect of the Dendrobium polysaccharides on CCl4-induced liver injury. The determination of the polysaccharides revealed that the polysaccharide and mannose contents of the FDO were significantly higher than their dried counterparts, and the homogeneous arrangement of the polysaccharides in the FDO was degraded into three polysaccharide fragments of different molecular weights in the DDO. Overall, our data identified differences in the antioxidant activities of the FDO and DDO, as well as the reasons for these differences.  相似文献   
9.
Mycotoxigenic fungi have attracted special attention due to their threat to food security and toxicity to human health. Aqueous extract of Zingiber officinale Roscoe was used as reducing and capping agent for the synthesis of silver (AgNPs), copper (CuNPs), and zinc oxide (ZnONPs) nanoparticles. UV-Visible spectra of the AgNPs, CuNPs, and ZnONPs showed absorption peaks at λmax 416 nm, 472 nm, and 372 nm, respectively. Zeta potential of AgNPs, CuNPs, and ZnONPs were −30.9, −30.4 and −18.4 mV, respectively. ZnONPs showed the highest activity against Aspergillus awamori ZUJQ 965830.1 (ZOI 20.9 mm and MIC 24.7 µg/mL). TEM micrographs of ZnONPs-treated A. awamori showed cracks and pits in the cell wall, liquefaction of the cytoplasmic content, making it less electron-dense. The sporulation and ochratoxin A production of A. awamori was inhibited by ZnONPs in a concentration-dependent pattern. The inhibition percentage of OTA were 45.6, 84.78 and 95.65% for 10, 15, 20 of ZnONPs/mL, respectively.  相似文献   
10.
Abstract

The stems of Dendrobium huoshanense have long been used to prevent various diseases, including inflammatory diseases. This study was aimed to explain the anti-inflammatory effect of D. huoshanense stems in LPS-induced RAW 264.7 macrophages and to discover potential anti-inflammatory compounds. Results exhibited that D. huoshanense stems ethanol extract could significantly inhibit LPS-induced production of NO, TNF-α and IL-1β. Based on bioassay guided strategy, four bibenzyls (14) were isolated from D. huoshanense stems for the first time. Anti-inflammatory assay showed 14 could remarkably inhibit the production of NO in LPS-induced macrophages. Moreover, quantitative RT-PCR analysis displayed that the mRNA levels of iNOs, TNF-α and IL-1β could also be significantly reduced by 14. These results suggested that D. huoshanense stems ethanol extract and bibenzyls 14 might be well developed as therapeutic agent to prevent inflammatory diseases.  相似文献   
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