A new bidesmoside triterpenoid saponin from Stauntonia chinensis

A new bidesmoside triterpenoid saponin,named stauntoside C1(1) has been isolated from Stauntonia chinensis.Its structure was established by means of spectral and chemical methods.     

Rapid determination and pharmacokinetics study of lignans in rat plasma after oral administration of Schisandra chinensis extract and pure deoxyschisandrin

A simple, sensitive and rapid method for analysis of six lignans in rat plasma after oral administration of Schisandra chinensis extracts, utilizing liquid chromatography tandem mass spectrometry (LC‐MS), was established and validated. Plasma samples were prepared by one‐step protein precipitation using acetonitrile and the analytes were separated on an SB‐C₁₈ column (100 mm × 3.0 mm, 3.5 µm) with the mobile phase of acetonitrile–water at a flow‐rate of 0.8 mL/min. Analytes were determined in a single‐quadrupole mass spectrometer in the selected ion monitoring (SIM) mode using electrospray source with positive mode. The method was proved to be rapid, sensitive and reproducible, and it was successfully applied to the pharmacokinetic studies of six lignans in rat plasma after oral administration of Schisandra chinensis extracts. In this research, the pharmacokinetics of deoxyschisandrin was also studied following oral administration of the pure deoxyschisandrin. It was found that most of the pharmacokinetic parameters of deoxyschisandrin in the extract were changed significantly compared with those in monomer. The content assay also revealed that the concentrations of the lignan in the extract increased in vivo compared with the pure monomer. Some ingredients in the extract may increase the dissolution of deoxyschisandrin, delay its elimination and enhance its bioavailability in rat. Copyright © 2010 John Wiley & Sons, Ltd.     

Homology Modeling and Molecular Docking Studies of (S)‐Scoulerine 9‐O‐Methyltransferase from Coptis chinensis

(S)‐Scoulerine 9‐O‐methyltransferase (SMT), belonging to the S‐adenosyl‐L‐methionine (SAM)‐dependent O‐methyltransferase family, is an essential enzyme in the berberine biosynthetic pathways. In order to study the interactions of SMT with its substrate and further to understand the catalytic mechanism and substrate specificity, a three dimensional model of SMT from Coptis chinensis was constructed by homology modeling using the crystal structure of caffeic acid/5‐hydroxyferulic acid 3/5‐O‐methyltransferase (COMT) as a template. The three dimensional structure of SMT, which was mainly composed of α‐helices and some β‐sheets, was similar to that of COMT. In contrast with COMT, the non‐conserved residues in the substrate binding pocket of SMT might be responsible for their differences in the substrate specificity. Val119 and Asp254 in SMT were the key residues for orienting substrate for methylation as both residues had H‐bonds with (S)‐scoulerine. The methylation of (S)‐scoulerine involved deprotonation of the 9‐hydroxyl group by His253 and Asp254 in SMT followed by a nucleophilic attack on the SAM‐methyl resulting in the product, (S)‐tetrahydrocolumbamine.     

柱前衍生-反相高效液相色谱法测定荔枝果蒂中的氨基酸

建立了AccQ· Tag柱前衍生-高效液相色谱法测定荔枝果蒂中氨基酸含量的方法.荔枝果蒂样品在120℃下真空水解22 h,再与AQC衍生剂进行衍生,并采用反相液相色谱法-荧光检测器进行分析,外标法计算样品中17种氨基酸的含量.17种氨基酸在35 min内可完全分离,荔枝果蒂中氨基酸的含量在2.5～25 μmol/L范围内与色谱峰面积呈良好的线性关系,相关系数不小于0.999.方法的加标回收率在71.2％～92.0％之间,测定结果的相对标准偏差为3.16％～9.94％(n=6),方法的检出限(S/N=3)在0.000 5～0.0012 mg/L之间.     

北五味子果实、茎和叶中微量元素的测定

采用硝酸和过氧化氢混合酸体系作消化液,利用电感耦合等离子质谱(ICP-MS),对延边地区不同产地五味子中微量元素的含量,进行了测定和研究。测定了不同产地五味子叶、茎、果实中Mg、Ca、Fe、Zn、Cu、Mn、Cr?Ni?Pb?Cd等19种元素的含量水平。测定结果显示五味子中K、Ca、Mg、Fe含量丰富,而Pb、Cd的含量很低。不同地区的五味子茎、叶、果实中微量元素含量存在很大差异。     

Three New Triterpenoid Saponins from the Seeds of Aesculus chinensis

Inpreviouspaperswehavereportedtheisolationandidentificationofescinsla,fo,IVa.IVbandIVel2.Nowwedescribethestructureelucidationofthreemorenewtriterpenoidsaponins.namedescinsIVc(l),IVd(2)andIVf(3).CompoundIwasisolatedaswhiteamorphouspowder.HR-SI-MSrevealedthecompositionofC,,H,,O,,bymolecularionpeakatm/z1129.5438.Comparedwiththe:3CandiHNMRspectraofescinla,compoundIisalsoaglycosideofprotoaescigeninacylatedbythetigloylandtheacetylgroup.Thesignificantdifferencesbetweenthemwerethechemicals…     

A New Bianthraqinonc Glycoside from Eremurus chinensis

Eremurus chinensis Fedtch has a wide distribution in the western part of China; it hasbeen used in Chinese folk medicine for the treatment of rheumatism and physicalweaknessl. Only few reports describe polysaccharides'-' rather than other chemicalconstituents from the genus Eremurus. We report here the isolation and structuralelucidation of a new bianthraquinone glycoside, 8-O- P -D-glucopyranosyl-2,7'-hi(l,8dihydroxy-3-methyl-9,10-anthraqu 1 from E. chinensis.The EtOAc soluble fraction ob…     

Secoiridoid Glucosides and Anti-Inflammatory Constituents from the Stem Bark of Fraxinus chinensis

Qin Pi (Fraxinus chinensis Roxb.) is commercially used in healthcare products for the improvement of intestinal function and gouty arthritis in many countries. Three new secoiridoid glucosides, (8E)-4′′-O-methylligstroside (1), (8E)-4′′-O-methyldemethylligstroside (2), and 3′′,4′′-di-O-methyl-demethyloleuropein (3), have been isolated from the stem bark of Fraxinus chinensis, together with 23 known compounds (4–26). The structures of the new compounds were established by spectroscopic analyses (1D, 2D NMR, IR, UV, and HRESIMS). Among the isolated compounds, (8E)-4′′-O-methylligstroside (1), (8E)-4′′-O-methyldemethylligstroside (2), 3′′,4′′-di-O-methyldemethyloleuropein (3), oleuropein (6), aesculetin (9), isoscopoletin (11), aesculetin dimethyl ester (12), fraxetin (14), tyrosol (21), 4-hydroxyphenethyl acetate (22), and (+)-pinoresinol (24) exhibited inhibition (IC₅₀ ≤ 7.65 μg/mL) of superoxide anion generation by human neutrophils in response to formyl-L-methionyl-L-leuckyl-L-phenylalanine/cytochalasin B (fMLP/CB). Compounds 1, 9, 11, 14, 21, and 22 inhibited fMLP/CB-induced elastase release with IC₅₀ ≤ 3.23 μg/mL. In addition, compounds 2, 9, 11, 14, and 21 showed potent inhibition with IC₅₀ values ≤ 27.11 μM, against lipopolysaccharide (LPS)-induced nitric oxide (NO) generation. The well-known proinflammatory cytokines, tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6), were also inhibited by compounds 1, 9, and 14. Compounds 1, 9, and 14 displayed an anti-inflammatory effect against NO, TNF-α, and IL-6 through the inhibition of activation of MAPKs and IκBα in LPS-activated macrophages. In addition, compounds 1, 9, and 14 stimulated anti-inflammatory M2 phenotype by elevating the expression of arginase 1 and Krüppel-like factor 4 (KLF4). The above results suggested that compounds 1, 9, and 14 could be considered as potential compounds for further development of NO production-targeted anti-inflammatory agents.     

A New Nortriterpenoid Glycoside from Sinofranchetia chinensis

Sinofranchetia chinensis is a traditional Chinese medicinal plant widely distributed in China, which has been used as an antirheumatic, antiphlogistic, analgesic and diuretic drug1. We isolated a new 30-nortriterpenoid saponin 1. This paper deals with the structural elucidation of 1.Sinofoside A (1). White powder from MeOH, mp. 225-230(C (dec.). It responded positively to the Libermann Burchard test2. Its IR absorptions((cm-1): 1730-1740 ester group, 3400-3420 hydroxyl, and 1640-1650 C=C…     

金莲花抑菌抗病毒活性成分的初步研究

用柱层析等色谱分离手段从金莲花中得到3个纯化合物,通过UV、IR、1H-NMR等现代波谱技术分别鉴定为原金莲酸、牡荆甙和荭草甙.对上述化合物和所提取的总黄酮样品进行抑菌、抗病毒活性研究.结果表明,总黄酮、牡荆甙和荭草甙对金黄色葡萄球菌和表皮葡萄球菌有很好的抑制效果,并对副流感病毒有强的抑制作用.该项研究是由本实验室首次报道.