Flavonol glycosides from the aerial parts of<Emphasis Type="Italic">Aceriphyllum rossii</Emphasis> and their antioxidant activities

The methanol extract obtained from the aerial parts ofAceriphyllum rossii (Saxifragaceae) was fractionated into ethyl acetate (EtOAc),n-BuOH and H₂O layers through solvent fractionation. Repeated silica gel column chromatography of EtOAc andn-BuOH layers afforded six flavonol glycosides. They were identified as kaempferol 3-O-β-D-glucopyranoside (astragalin,1), quercetin 3-O-β-D-glucopyranoside (isoquercitrin,2), kaempferol 3-O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside (3), quercetin 3-O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyrano-side (rutin,4), kaempferol 3-O-[α-L-rhamnopyranosyl (1→4)-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside] (5) and quercetin 3-O-[α-L-rhamnopyranosyl (1→4)-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside] (6) on the basis of several spectral data. The antioxidant activity of the six compounds was investigated using two free radicals such as the ABTS free radical and superoxide anion radical. Compound1 exhibited the highest antioxidant activity in the ABTS2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging method. 100 mg/L of compound1 was equivalent to 72.1±1.4 mg/L of vitamin C, and those of compounds3 and5 were equivalent to 62.7±0.5 mg/L and 54.3±1.3 mg/L of vitamin C, respectively. And in the superoxide anion radical scavenging method, compound5 exhibited the highest activity with an IC₅₀ value of 17.6 ± 0.3 μM. In addition, some physical and spectral data of the flavonoids were confirmed.     

东北山梅花根化学成分的研究

目的研究东北山梅花(Philadelphus schrenkii Rupr.)根的化学成分。方法利用柱色谱层析、薄层层析色谱法分离纯化化合物,光谱分析鉴定结构。结果得到化合物豆甾醇。结论该化合物为首次从东北山梅花根中分离得到。     

Antioxidant and Anti‐α‐glucosidase Compounds from the Rhizome of Peltiphyllum peltatum (Torr.) Engl

The antioxidant, anti‐α‐glucosidase and anticholinesterase effects of the alcohol extract of fresh underground rhizomes of Peltiphyllum peltatum were studied. A potent antioxidant activity accompanied by a selective α‐glucosidase effect was observed for the crude extract. Further activity‐guided fractionation (petroleum ether, chloroform, ethyl acetate, n‐butanol and water) resulted in the identification of the ethyl acetate fraction with the highest antioxidant effect. Gallic acid, methyl‐3‐O‐methyl gallate, catechin, gallocatechin, bergenin and 11‐O‐galloylbergenin were isolated from the ethyl acetate fraction. While all the isolated compounds did show a variable degree of radical scavenging effect, 11‐O‐galloylbergenin was identified as the selective α‐glucosidase inhibitor. The isolation, structural elucidation and biological effects of these compounds are discussed. Copyright © 2012 John Wiley & Sons, Ltd.     

Immunomodulatory effect of bergenin and norbergenin against adjuvant-induced arthritis--a flow cytometric study

Bergenin (1), a C-glycoside of 4-O-methyl gallic acid, isolated from rhizomes of Bergenia stracheyi (Saxifragaceae) and its O-demethylated derivative norbergenin (2), prepared from 1, are reported to show anti-arthritic activity through possible modulation of Th1/Th2 cytokine balance. Flow cytometric study showed that the oral administration of 1 and 2 at doses of 5, 10, 20, 40 and 80 mg/kg per oral dose inhibit the production of proinflammatory Th1 cytokines (IL-2, IFN-gamma and TNF-alpha) while as potentiate anti-inflammatory Th2 cytokines (IL-4 and IL-5) in the peripheral blood of adjuvant-induced arthritic balb/c mice. This shows the potential Th1/Th2 cytokine balancing activity of 1 and 2 which is strongly correlated with their anti-arthritic activity. At similar dose levels, the effect of 2 was found to be more than that of 1. The oral LD(0) for 1 and 2 was more than 2000 mg/kg body weight of the mice.     

Anticomplement activities of oleanolic acid monodesmosides and bisdesmosides isolated fromTiarella polyphylla

Seven known oleanolic acid glycosides (1-7) were isolated from the MeOH extract of Tiarella polyphylla. The structures were identified to be 3-O-(beta-D-glucopyranosyl) oleanolic acid (1), 3-O-[beta-D-glucopyranosyl-(1-->3)-beta-D-glucopyranosyl] oleanolic acid (2), 3-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl] oleanolic acid (3), 3-O-[beta-D-glucopyranosyl-(1-->3)-beta-D-glucopyranosyl] oleanolic acid 28-O-beta-D-glucopyranosyl ester (4), 3-O-[beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl] oleanolic acid 28-O-beta-D-glucopyranosyl ester (5), 3-O-[a-L-rhamnopyranosyl-(1-->3)-beta-D-glucuronopyranosyl] oleanolic acid (6), and 3-O-[alpha-L-rhamnopyranosyl-(1-->3)-beta-D-glucuronopyranosyl] oleanolic acid 28-O-beta-D-glucopyranosyl ester (7) on the basis of physicochemical and spectral data. These triterpene glycosides were tested for the anticomplement activity and hemolytic activity. Bisdesmosidic saponins, 4, 5, and 7, showed anticomplement activity; in contrast, monodesmosidic saponins, 1-3, and 6, showed direct hemolytic activity. Methyl esterified monodesmosidic saponins showed anticomplement activity at a low concentration and hemolytic activity at a high concentration.     

Structure determination of a new lupane-type triterpene, tiarellic acid, isolated fromTiarella polyphylla

A new 27-carboxylic lupane-type triterpene, tiarellic acid (1), was isolated from Tiarella polyphylla together with corosolic acid (2) and tormentic acid (3). Tiarellic acid was characterized as 3,23-dihydroxy-20(29)-lupen-27-oic acid and its NMR data were unambiguously assigned using 2-D NMR techniques.     

藏族医学药用虎耳草科植物药材品种及标准的整理分析

通过查阅藏族医药相关的文献和标准,对藏族医学药用虎耳草科植物药材的品种、基原及其标准收载、功效等情况进行了整理。结果表明,藏族医学药用的虎耳草科植物共8属75种(含变种),涉及21个药材品种。在《中国药典》《部颁药品标准·藏药》《藏药标准》及地方中药标准中共收载了9个常用品种,包括松地、色地、亚吉玛、奥叻旦赛尔宝、见司达兀、塞果、喀图儿、桑滴、毛青红等,占药材品种数的42.9%;在相关藏族药标准及文献中,各药材品种的藏文名称和藏文音译汉文名称及其基原物种存在较大的差异,"同物异名""同名异物"等现象常见。各标准中收载的绝大多数品种(如松地、色地、亚吉玛等)仅有性状、显微及理化鉴别项,其质量标准水平较低。基于分析结果,该文认为应加强对藏医学药用虎耳草科药材品种的本草考证、资源和使用现状调查,进行品种整理,建立完善的质量标准,并进行药效物质基础及生物活性等的比较研究,以促进资源的合理利用,保障临床用药准确、安全有效。     

Phytochemical, antioxidant and anti-α-glucosidase activity evaluations of Bergenia cordifolia

The antioxidant, anti-α-glucosidase and anticholinesterase activity of the leaves and rhizomatous extract of Bergenia cordifolia were investigated. The rhizomes extract that showed a higher degree of 1,1-diphenyl-2-picrylhydrazyl radical scavenging and anti-α-glucosidase activity than reference compounds (rutin and acarbose respectively) were subjected to phytochemical analysis. The study revealed that previously unknown minor constituents from the plant, (+)-catechin 3-O-gallate, (+)-catechin 3,5-di-O-gallate and 1,2,4,6-tetra-O-galloyl-β-D-glucopyranoside, were the radical scavenging and anti-α-glucosidase principles. These compounds as well as the crude extracts were weak acetylcholienesterase inhibitors, suggesting a higher degree of selectivity against α-glucosidase enzyme. In comparison with the minor constituents, the previously known major constituents of the plant, bergenin and arbutin, were poor radical scavengers and enzyme inhibitors.     

常山叶中一种新的喹唑酮生物碱

从常山中分离得到一种新的生物碱，命名为新常山碱，还分离得到已知的常山碱、异常山碱、香豆素，双氢黄酮和香草醛。新生物碱的结构通过波谱解析和与自常山碱的半合成产品对照来确定。     

Effect of the rhizomes of Astilbe chinensis on UVB-induced inflammatory response

The EtOH extract from the rhizomes of Astilbe chinensis (Saxifragaceae) exhibited potent antioxidant activity in preliminary screening. Since oxidative stress is known to be involved in the inflammatory response after UVB exposure, the ability of an A. chinensis extract to inhibit UVB-induced PGE2 and NO production was examined. UVB irradiation (35 mJ/cm2) increased PGE2 and NO production, which were significantly decreased by pre-administration of the extract in a dose-dependent manner. The A. chinensis extract also preserved the cellular antioxidant capacity after UVB irradiation, which was determined by the GSH content. UVB irradiation enhanced the formation of ROS in the keratinocytes, which was determined using DCFH-DA, a redox sensitive dye. The levels of intracellular ROS were also significantly reduced by pre-treatment of the extract in a dose-dependent manner measured 9 h after UVB irradiation. The results suggest that the A. chinensis extract may have a protective effect on the UVB-injured keratinocytes by inhibiting PGE2 and NO production, possibly through the inhibition of intracellular ROS accumulation.