细茎石斛多糖的降血糖活性作用

观察细茎石斛 ( Dendrobium moniliforme ( L .) Sw .)多糖对多种模型小鼠血糖水平的影响 ,探讨其降血糖作 用机理 .采用昆明种小鼠分组 ,分别以细茎石斛多糖 (100 mg· kg - 1 、200 mg· kg - 1 )、格列苯脲片 (50 mg· kg - 1 )、盐 酸苯乙双胍 (50 mg· kg - 1 )或生理盐水灌胃 ,测定各正常小鼠、肾上腺素性糖尿病和四氧嘧啶性糖尿病小鼠的血糖 水平 .结果 100 mg · kg - 1 、200 mg · kg - 1 两个剂量的细茎石斛多糖均能显著降低肾上腺素、四氧嘧啶引起的糖尿病 小鼠的血糖水平 (p < 0. 01) ,提高四氧嘧啶性糖尿病小鼠的葡萄糖耐量 (p < 0. 01),但对正常小鼠的血糖水平无影 响 .细茎石斛多糖具有明显的降血糖作用 ,是一种值得开发利用的降糖植物多糖.     

A new (propylphenyl)bibenzyl derivative from Dendrobium williamsonii

A new (propylphenyl)bibenzyl derivative, dendrowillol A (1), along with 22 known compounds were isolated from the whole plants of Dendrobium williamsonii. Their structures were elucidated by means of extensive spectroscopic analysis. Cytotoxicity evaluation against five human tumour lines showed that all the compounds tested displayed very weak cytotoxicity when compared with the positive control taxol, but selective inhibitory effects on HL-60 for several compounds tested were observed, with IC₅₀ values ranging from 4.48 to 11.04 μM.     

超声搅拌悬浮液进样FAAS法测定铁皮石斛(枫斗)中的铜

研究了铁皮石斛 (枫斗 )中铜的分析方法。样品在 80± 2℃烘干 4h ,研磨过 2 0 0目筛 ,然后加入 5mL 0 1 5 %琼脂悬浮液 ,用超声搅拌混匀后直接上机测定。测定结果与传统湿法一致 ,t检验表明两者无显著性差异 ,相对误差小于 0 96%。该法简便、快速、准确。     

Benzopyran derivatives from endophytic Daldinia eschscholzii JC-15 in Dendrobium chrysotoxum and their bioactivities

Five new benzopyran derivatives (2–6) and a new natural product (1) were isolated from endophytic Daldinia eschscholzii in Dendrobium chrysotoxum and determined as (R)-2,3-dihydro-2,5-dihydroxy-2-methylchromen-4-one (1), (2R, 4S)-2,3-dihydro-2-methyl-benzopyran-4,5-diol (2), (R)-3-methoxyl-1-(2,6-dihydroxy phenyl)-butan-1-one (3), 7-O-α-d-ribosyl-5-hydroxy-2-methyl-4H-chromen-4-one (4), 7-O-α-d-ribosyl-2,3-dihydro-5-hydroxy-2-methyl-chromen-4-one (5), daldinium A (6). These compounds were evaluated for their antimicrobial activity, anti-acetylcholinesterase, nitric oxide inhibition, anticoagulant, photodynamic antimicrobial activities and glucose uptake of adipocytes. Some compounds showed photoactive antimicrobial activities and glucose uptake stimulating activities.     

Ultrasound/microwave‐assisted solid–liquid–solid dispersive extraction with high‐performance liquid chromatography coupled to tandem mass spectrometry for the determination of neonicotinoid insecticides in Dendrobium officinale

A one‐step ultrasound/microwave‐assisted solid–liquid–solid dispersive extraction procedure was used for the simultaneous determination of eight neonicotinoids (dinotefuran, nitenpyram, thiamethoxam, clothianidin, imidacloprid, acetamiprid, thiacloprid, imidaclothiz) in dried Dendrobium officinale by liquid chromatography combined with electrospray ionization triple quadrupole tandem mass spectrometry in multiple reaction monitoring mode. The samples were quickly extracted by acetonitrile and cleaned up by the mixed dispersing sorbents including primary secondary amine, C₁₈, and carbon‐GCB. Parameters that could influence the ultrasound/microwave‐assisted extraction efficiency such as microwave irradiation power, ultrasound irradiation power, temperature, and solvent were investigated. Recovery studies were performing well (70.4–113.7%) at three examined spiking levels (10, 50, and 100 μg/kg). Meanwhile, the limits of quantification for the neonicotinoids ranged from 0.87 to 1.92 μg/kg. The method showed good linearity in the concentration range of 1–100 μg/L with correlation coefficients >0.99. This quick and useful analytical method could provide a basis for monitoring neonicotinoid insecticide residues in herbs.     

New bisbibenzyl and phenanthrene derivatives from Dendrobium scabrilingue and their α-glucosidase inhibitory activity

Abstract

Phytochemical investigation of the whole plant of Dendrobium scabrilingue resulted in the isolation of two new compounds namely dendroscabrols A (1) and B (2), along with eight known compounds (3–10). The structures of these compounds were determined by NMR and HR-ESI-MS experiments. All of the isolates were evaluated for their α-glucosidase inhibitory effect. Dendroscabrol B (2) and RF-3192C (10) showed the most potent α-glucosidase inhibitory activity. Dendroscabrol A (1), gigantol (5), coelonin (7) and lusianthridin (9) also exhibited strong activity as compared with the positive control acarbose.     

铁皮石斛的裂解气相色谱指纹图谱及其系统聚类分析

采用裂解气相色谱/质谱法(Py-GC/MS)测定了10种不同产地的铁皮石斛并结合系统聚类分析法比较了这些铁皮石斛的指纹图谱,采用释放气体分析法考察了裂解温度对指纹图谱的影响。结果表明,0.4 mg样品在450 ℃下可瞬间裂解,10种样品的指纹图谱具有相似性,且重现性好;采用系统聚类分析能区别不同产地的样品。本法快速、简便、准确,不失为药材质量控制的良好方法。     

铁皮石斛原球茎多糖DCPP3c-1的分离纯化及结构初步分析

铁皮石斛原球茎粗多糖(DCPP)经阴离子交换纤维素柱(DEAE-2)和凝胶柱(Sephadex G-200)依次层析,分离纯化得灰色多糖DCPP3c-1.其纯度经比旋光度法、柱层析、紫外扫描检测,组分和结构经薄层层析、高效液相色谱、红外光谱及高碘酸钠氧化等试验分析.结果显示DCPP3c-1为均一组分,相对分子质量为72.4 ku.由甘露糖、鼠李糖、半乳糖醛酸、葡萄糖、半乳糖和阿拉伯糖组成,其分子物质的量之比为1.120 4:1:1.046:23.354:3.828:1.046.分子中1→6残基占14%,1→2或1→4残基占40.7%,1→3键占45.3%.红外光谱显示其具有多糖特征吸收峰,并存在吡喃糖苷键.DCPP3c-1是首次从液体悬浮培养的原球茎中分离得到的新型酸性杂多糖组分.     

Application of two‐dimensional near‐infrared (2D‐NIR) correlation spectroscopy to the discrimination of three species of Dendrobium

The objective of this paper was to apply two‐dimensional (2D) near‐infrared (NIR) correlation spectroscopy to the discrimination of three species of Dendrobium. Generalized 2D‐NIR correlation spectroscopy was able to enhance spectral resolution, simplify the spectrum with overlapped bands and provide information about temperature‐induced spectral intensity variations that was hard to obtain from one‐dimensional NIR spectroscopy. The FT‐NIR spectra were measured over a temperature range of 30–140°C. The 2D synchronous and asynchronous spectra showed remarkable differences within the range of 5600–4750 cm⁻¹ between different species of Dendrobium. Copyright © 2009 John Wiley & Sons, Ltd.     

春石斛组织培养技术研究

以春石斛Dendrobium nobile white Christmas“seagull”品种的不同生理年龄的不同组织为外植体，研究了灭菌方式对成活率的影响；BA与NAA不同浓度组合对诱导不定芽及不定芽增殖的影响；GA3和亚精胺对壮苗的作用．结果表明：0．1％HgCl26min组合嫩茎成活率最高；0．1％HgCl28min老茎成活率最高；0．5mg／L NAA和1．0mg／L BA组合最利于诱导不定芽；GA3和亚精胺对不定芽的增殖和生长有促进作用．