HPLC柱切换技术用于同时分析鱼腥草中3种黄酮类成分

利用柱切换技术解决了鱼腥草中难分离组分的分离和低含量组分的定量问题。以Synergi Fusion-RP柱(250 mm×4.6 mm i.d.,4μm)作为预柱,甲醇-0.05%磷酸溶液作流动相,以Acclaim120 C18柱(250mm×4.6 mm i.d.,5μm)作为分析柱,乙腈-0.05%磷酸溶液作流动相,对鱼腥草中的3种黄酮类成分进行分析。该方法在10.0～1 000.0 mg.L-1范围内线性关系良好,相关系数(r)不低于0.998,回收率为95%～99%,RSD值均小于3%。该方法操作简便、快速,可作为分析鱼腥草中黄酮类组分的有效手段。     

Extraction and Crystal Structure of Pedunculoside

The title compound of pedunculoside (C36H58O10), a main active triterpenoid saponin of Ilicis Rotundae Cortex, was isolated from the dried bark of Ilex rotunda Thunb., and characterized by X-ray diffraction analysis. It crystallizes in the orthorhombic system, space group P212121 with C36H58O10, a=13.046(3), b=21.038(4), c=28.413(6) , V=7798.28(3) ·3, Z=8, Dc=1.109 g/cm3, Mr=650.82, F(000)=2832, and μ=0.080 mm-1. The final R=0.0765 and wR=0.1736 for 15117 observed reflections (I > 2σ(I)). The molecular crystal structure of pedunculoside shows relative stereochemistry of 3β,19α,23-trihydroxy-urs-12-en-28-oic acid-28-O-β-D-glucopy- ranosyl ester. The molecule is composed of one glucopyranosyl ring and five six-membered rings with ring junctures of A/B trans, B/C trans, and D/E cis. There are two C36H58O10 molecules in an asymmetric unit, and the title compound is stacked into a 2D layer structure through hydrogen bonds.     

何首乌及其提取物的漫反射和衰减全反射红外光谱研究

采用漫反射和衰减全反射两种红外光谱分析何首乌及其提取物。结果表明,以丙酮为提取剂时,何首乌其提取物中,韧皮部的有效成分含量最高,木质部的有效成分含量最低;通过两种方式的比较,发现何首乌及提取物的红外谱图存在一定的差异,何首乌在3 576和3 147cm-1有两个平缓的吸收峰,而提取物则在3 351cm-1有一强吸收峰,表明提取物中的OH…活性成分较多;同时,何首乌在931,859,766和709cm-1处有明显的吸收,而其提取物则没有,这也表明提取的是活性成分。     

不同产地三叶木通中总黄酮含量的测定

考察了超声波提取法对三叶木通总黄酮提取的影响条件,其最优条件为:提取次数3次,料液比1:30(g/mL),提取时间30min,乙醇浓度60%。用超微量微孔板分光光度法对不同产地,不同部位三叶木通总黄酮含量进行测定,结果表明,不同产地三叶木通之间总黄酮含量差异显著,不同部位之间差异也显著,可见不同产地因不同的生长环境、温度、湿度等因素对三叶木通总黄酮含量影响较大。本实验为以后更好的开发利用三叶木通资源提供一定的理论依据和指导意义。     

鱼腥草多糖提取工艺及成分分析研究

 研究了鱼腥草多糖的提取工艺.结果表明,鱼腥草多糖的最佳提取工艺为:液固比(V/m,mL/g,下同)30:1,80℃水浴提取3次,每次2 h,多糖提取率达3.5%.除蛋白、上凝胶层析分离柱得多糖纯品,用WatersSep-pak C₁₈固相萃取小柱预分离,以Waters carbohydrate高效糖柱为固定相,V(乙腈):V(水)=70:30为流动相分离,蒸发光散射仪为检测器检测,得到鱼腥草多糖组成m(木糖):m(果糖):m(阿拉伯糖):m(半乳糖)=2.209:1.587:1.000:2.092.     

HPLC法同时测定忍冬的花、叶中木犀草苷和绿原酸含量

建立了HPLC法测定忍冬的花、叶中木犀草苷和绿原酸含量的方法。应用Shim-pack ODS色谱柱 (4.6×250 mm, 5 μm),乙腈/0.2 %甲酸水梯度洗脱,流速为1.0 mL/min,检测波长为350 nm。在此色谱条件下,各组分在30 min内均得到良好分离。用该方法测定了3个品种忍冬的花、叶中木犀草苷和绿原酸的含量,结果表明亚特、意大利和九丰一号忍冬叶中木犀草苷含量分别为5.856、2.454和4.633 mg·g^-1,明显高于花。     

火焰原子吸收法测定白英中的微量元素

为分析白英药效与微量元素的关系,样品经微波消解,采用火焰原子吸收法测定了白英中Fe、Cu、Zn、Mn、Mg、Ca的含量。结果表明,该法快速、简便、准确,6种元素的回收率为98．00％～103．60％,RSD为0．326％-1．216％。白英中Ca、Fe元素含量较高。     

Complete assignments of 1H and 13C NMR spectral data for three new triterpenoid saponins from Ilex hainanensis Merr

Three new oleanane-type triterpenoid saponins, ilexhainanoside C, D and E, all with 24, 28-dioic acid groups, were isolated from the leaves of Ilex hainanensis. They were 3beta-hydroxyolean-12-ene-24, 28-dioic acid-28-O-beta-D-glucopyranoside(1), 3beta, 19alpha-dihydroxyolean-12-ene-24, 28-dioic acid-28-O-beta-D-glucopyranoside(2) and 3beta, 29-dihydroxyolean-12-ene-24, 28-dioic acid-28-O-beta-D-glucopyranoside(3). The structures of these three new compounds were elucidated and complete assignments of the (1)H and (13)C NMR spectroscopic data were achieved by 1D and 2D NMR experiments [heteronuclear single quantum coherence (HSQC), HMBC and rotational nuclear Overhauser effect spectroscopy (ROESY)].     

MALDI‐ and LDI‐MS saponin fingerprint of leaves and stick components of commercial yerba mate (Ilex paraguariensis)

Yerba mate (YM) is massively produced and consumed as an infusion in South America and spreading all over the world. This product is obtained from dried leaves of Ilex paraguariensis Saint Hilaire, mixed with fragments of dried branches (sticks). For its commercialization, YM must have a minimum percentage of leaves because its presence determines YM quality and price. Till today, a mechanical methodology to determine the relative amount of components (sticks, leaves, and powder) is used. There is not any modern analytical method that provides information for quick characterization of the YM components. Typical saponin fingerprints for leaves and sticks were found by using ultraviolet matrix‐assisted laser desorption ionization and ultraviolet laser desorption ionization mass spectrometry. Then, their possible application as useful tools for quick characterization of components of commercial YM (leaves and sticks) is presented. Furthermore, fingerprints obtained from authentic samples of Ilex paraguariensis and Ilex dumosa are also included and discussed. Each Ilex show typical saponin fingerprints for leaves and sticks.     

A new benzofuran from the heartwood of Dalbergia latifolia

A new benzofuran compound, named 2-[5-hydroxy-4-methoxy-2-(3-p-henyl-trans-allyloxy)benzyl]-5-hydroxy-6-methoxy-3-phenylbenzofuran (1), together with (+)-obtusafuran (2) and isoparvifuran (3), was isolated from the heartwood of Dalbergia latifolia. Their structures were elucidated by a combination of spectroscopic methods and comparison with the literature. Compounds 2 and 3 were obtained from this plant for the first time. Compound 1 exhibited moderated antioxidant effect for scavenging 1,1-diphenyl-2-picryhydrazyl (DPPH) free radical (IC₅₀ = 96.7 ± 8.9 μM).