石斛属菲类成分及其药理作用研究进展

菲类化合物是石斛属植物的特征成分之一,可分为简单菲、二氢菲、双菲及菲醌（酮）等菲衍生物4种类型。综述了金钗石斛、铁皮石斛、束花石斛、细茎石斛、流苏石斛、密花石斛、鼓槌石斛、曲轴石斛、石斛兰和绒毛石斛10种石斛属植物中毛兰菲、鼓槌菲、杓兰素等20个菲类活性成分,并介绍其抗肝纤维化、抗肿瘤、抗炎、抗氧化、降血糖等药理活性,希望为该属植物的新药研发和临床应用提供参考。     

祖师麻中的木脂素类成分

目的 研究祖师麻的化学成分。方法 采用硅胶柱色谱,Pre-TLC,Pre-HPLC等方法进行分离纯化,并通过理化常数和波谱数据分析进行结构鉴定。结果 分离得到6个已知的木脂素类化合物,分别鉴定为(-)-松脂酚 （(-)-pinoresinol,1）、(+)-丁香树脂酚（(+)-syringaresinol,2）、(+)-里立脂素B二甲醚（(+)-liriorosinol-B-dimethyl ether,3）、(+)-丁香树脂酚双葡萄糖苷（(+)-syringaresinol-di-O-β-D-glucoside,4）、罗汉松脂醇（matairesinol,5）、woonenoside Ⅺ（6）。结论 化合物3、6为从瑞香属植物中首次分离得到,4、5为从祖师麻中首次分离得到。     

五味子木脂素类成分提取分离及抗肝炎作用

五味子别名山花椒、味子,为木兰科五味子属藤本植物,其脂素类化合物是母核为1,2,3,4-联苯-1,3-环辛二烯的一种常见木脂素,为五味子在肝炎治疗中的主要药理活性成分,本次研究就其成分提取分离方法及抗肝炎作用展开探讨,现综述如下。     

望春花中的一个苯并呋喃类木脂素

目的研究望春花Magnolia biondii Pamp 花蕾中的化学成分.方法采用色谱技术进行分离纯化,根据理化性质和现代波谱技术进行结构鉴定.结果从望春花的花蕾乙醇提取物中分离鉴定出1个苯并呋喃类新木脂素和2个已知木脂素, 分别鉴定为利卡灵B (licarin B) 1; 木兰脂素(magnolin) 2; 辛夷脂素(fargesin) 3.结论木兰属植物中木脂素多为双环氧型,苯并呋喃类新木脂素licarin B是首次从木兰科植物中分得.     

南天竹种子中木脂素类成分研究

目的研究南天竹种子的化学成分。方法采用正相硅胶、凝胶、微孔树脂、半制备高效液相柱色谱等手段分离,波谱法进行结构鉴定。结果从南天竹种子中分离得到7个木脂类化合物:丁香脂素(1)、松脂素(2)、杜仲树脂酚(3)、1-羟基松脂素(4)、gentioluteol(5)、berchemol(6)、berchemol-4’-O-β-D-吡喃葡萄糖苷(7)。结论化合物1~7均为首次从该植物中分离得到。     

叶下珠属植物中的木脂素类成分

本文概述了叶下珠属植物中木脂素的药理作用、结构类型、提取分离和光谱鉴别特征，为研究叶下珠属植物的化学及其新用途的开发提供参考。     

香榧假种皮中的木脂素成分

目的研究香榧假种皮中的化学成分。方法采用色谱技术分离纯化,自85%乙醇提取物中分得3个木脂素化合物,应用光谱技术(IR,EI-MS,¹HNMR,¹³CNMR,DEPT,2D-NMR),确定了它们的化学结构。结果3个化合物分别为松脂素(I),二氢脱水二聚松柏醇(II),(7,8-cis-8,8′-trans)-2′,4′-二羟基-3,5-二甲氧基-落叶松脂素(III)。结论 以上化合物均为首次从该植物中分得,其中III为一新化合物。     

黄酮木脂素水飞蓟宾类似物的合成及抗氧化活性

介绍第一个黄酮木脂素类化合物——水飞蓟宾类似物的主要成分、合成及抗氧化活性。大量研究结果表明,水飞蓟素具有保肝作用,还具有抗炎、抗肿瘤等活性。     

海风藤新木脂素类成分对缺血再灌注鼠脑损伤的保护作用

目的　探讨血小板活化因子 (PAF)受体拮抗剂海风藤新木脂素类成分对鼠脑梗死面积、局部脑血流量 (rCBF)及神经功能缺失征象的影响 ,并与传统的PAF受体拮抗剂银杏苦内酯相比较。方法　利用TTC染色结合球积仪、氢清除法组织血流计和临床神经功能评分标准等方法 ,分别对缺血、缺血再灌注及海风藤新木脂素类成分、银杏苦内酯治疗组鼠脑梗死面积、rCBF、神经功能缺失征象进行观察和比较。结果　海风藤新木脂素类成分、银杏苦内酯药物治疗组脑梗死面积较缺血再灌组明显减小 ,同时药物能改善缺血侧皮质rCBF的下降 ,并显著减轻脑缺血后的神经功能缺损。结论　海风藤新木脂素类成分与传统的PAF受体拮抗剂银杏苦内酯均具有显著的脑保护作用     

Three new bibenzyl derivatives from Dendrobium nobile

Three new bibenzyl derivatives have been isolated from the stems of Dendrobium nobile Lindl. (Orchidaceae). Their structures were established as 4,5-dihydroxy-3,3′,α-trimethoxybibenzyl (1), 4,4′-dihydroxy-3,3′,5,α-tetramethoxybibenzyl (2) and 4-hydroxy-3,3′,4′,5,α-pentamethoxybibenzyl (3) on the basis of spectroscopic analysis.     

A new phenanthrenequinone from Dendrobium draconis

A number of Dendrobium species (Orchidaceae) have been used as health foods. In Thailand, the tea prepared from the stems of Dendrobium draconis Rchb.f. (Orchidaceae) has been used as a blood tonic. Our phytochemical investigation of this plant led to the isolation of a new compound namely 5-methoxy-7-hydroxy-9,10-dihydro-1,4-phenanthrenequinone (1), along with four known stilbenoids including hircinol (2), gigantol (3), batatasin III (4), and 7-methoxy-9,10-dihydrophenanthrene-2,4,5-triol (5). The structures of these compounds were determined through extensive spectroscopic studies, including ¹H and ¹³C NMR, DEPT, COSY, NOESY, HMQC, HMBC, ESI-MS, and HR-ESI-MS experiments. In the DPPH-free radical assay, these stilbene derivatives showed appreciable antioxidant activity.     

Antioxidant compounds from the stem bark of Garcinia atroviridis

A new xanthone, namely garcinexanthone G (1), along with eight known compounds, stigmasta-5,22-dien-3β-ol (2), stigmasta-5,22-dien-3-O-β-glucopyranoside (3), 3β-acetoxy-11α,12α-epoxyoleanan-28,13β-olide (4), 2,6-dimethoxy-p-benzoquinone (5), 1,3,5-trihydroxy-2-methoxyxanthone (6), 1,3,7-trihydroxyxanthone (7), kaempferol (8) and quercetin (9), were isolated from the stem bark of Garcinia atroviridis. Their structures were elucidated based on spectroscopic methods including nuclear magnetic resonance (NMR-1D and 2D), UV, IR, and mass spectrometry. All the isolated compounds were evaluated for their antioxidant properties based on the DPPH radical scavenging activities. Results showed that 1,3,7-trihydroxyxanthone and quercetin showed significant antioxidant activities with EC₅₀ values of 16.20 and 12.68 μg/ml, respectively, as compared to the control, ascorbic acid (7.4 μg/ml).     

川、黔地区金钗石斛多糖的含量测定

目的:比较川、黔金钗石斛中有效成分多糖的含量,建立金钗石斛中多糖的含量测定方法。方法:采用水提醇沉法提取金钗石斛多糖,以葡萄糖为对照品,在紫外检测波长490nm处用苯酚-硫酸法测定不同产地金钗石斛中多糖的含量。结果:金钗石斛多糖的检测浓度在1.25～8.75μg·mL-1范围内与吸光度呈良好线性关系(r=0.9994)。贵州赤水金钗石斛的平均回收率为101.6%,RSD=1.9%(n=6),多糖含量为11.456%;四川合江金钗石斛的多糖含量为9.226%。结论:苯酚-硫酸法操作简便、可靠、准确、灵敏、稳定性好,适用于金钗石斛中多糖的含量测定。在川、黔地区金钗石斛多糖提取生产过程中,可优先选用贵州赤水金钗石斛。     

Antioxidant constituents from the stem ofSorghum bicolor

The EtOAc soluble fraction from the stem of Sorghum bicolor showed a strong free radical scavenging activity. Five major compounds were isolated from this fraction. They were identified by spectral data as methyl ferulate (1), methyl p-hydroxycinnamate (2), p-hydroxybenzaldehyde (3), tricin (4), and quercetin 3,4'-dimethyl ether (5). Among these compounds, 1 exhibited a strong, free radical scavenging activity on 1,1-diphenyl-2-picrylhydrazyl (DPPH) with an IC50 value of 0.7 microM. We further studied the effects of these isolated compounds on the lipid peroxidation in rat liver microsomes induced by non-enzymatic method. All five compounds showed anti-lipid peroxidation activity (IC50 values of 0.5, 0.4, 0.3 and 0.3 microM, respectively).     

Free Radical Scavenging Activity of Extracts from Thai Plants in Guttiferae and Schisandraceae Families

ABSTRACT

Five Thai plants from the Guttiferae (Hypericum hookerianum. Wight & Arn, Garcinia speciosa. Wall, Garcinia xanthochymus. Hook f. ex. T. Anderson, Cratoxylum formosum. ssp. pruniflorum. (Kurz) Gogel, and Calophyllum polyanthum. Wall ex Choisy) and one from the Schisandraceae (Schisandra verruculosa.) were extracted by methanol and chloroform. The extracts were screened for free radical scavenging activity using the DPPH assay. All extracts showed a dose-dependent antioxidant activity. The most potent with the lowest IC₅₀ values were observed in the methanol extracts from the wood of G. speciosa., which were 2.5- and 5.3-fold more potent than the two standard antioxidants, ascorbic acid and α.-tocopherol, respectively. Free radical scavenging activities ranging from moderate to high were observed in both methanol and chloroform extracts from H. hookerianum., C. formosum. ssp. pruniflorum., G. xanthochymus., S. verruculosa. and C. polyanthum.. The information from this study can explain the traditional use and the further development of these extracts into new pharmaceuticals.     

Antinociceptive and antioxidant potential of the crude ethanol extract of the leaves of Ageratum conyzoides grown in Bangladesh

Abstract

Context: Ageratum conyzoides Linn. (Asteraceae) is an annual herbaceous plant with a long history of traditional medicinal and agricultural uses; it is usually grown in the northeast part of Bangladesh.

Objective: The ethanol extract of the plant leaves was evaluated for preliminary phytochemical screening with its antinociceptive and antioxidant activities.

Materials and methods: The preliminary phytochemical analysis was performed on the basis of standard procedures. The analgesic activity of the extract was investigated using the acetic acid-induced writhing method in mice. Five complementary tests such as DPPH free radical scavenging, nitric oxide (NO) scavenging, reducing power, Fe⁺⁺ ion chelating ability and total phenolic content were used for determining antioxidant activities.

Results: The results of preliminary phytochemical analysis showed the presence of alkaloids, reducing sugars, saponins, gums, steroids, tannins and flavonoids. The extract possessed a significant dose-dependent DPPH free radical scavenging activity with an IC₅₀ value of 18.91?μg/ml compared to ascorbic acid (IC₅₀: 2.937?μg/ml) and butylated hydroxyanisole (IC₅₀: 5.10?μg/ml). The IC₅₀ value of the extract for NO scavenging (41.81?μg/ml) was also found to be significant compared to the IC₅₀ value of ascorbic acid (37.93?μg/ml). Moreover, the extract showed reducing power activity and Fe⁺⁺ ion chelating ability. The total phenolic amount was also calculated as quite high (378.37?mg/g of gallic acid equivalents) in the crude ethanol extract.

Discussion and conclusion: Therefore, the obtained results tend to suggest the antinociceptive and antioxidant activities of the ethanol extract of the plant leaves and justify its use in folkloric remedies.     

Synthesis and In Vitro Antioxidant Activity of New 3-Substituted-2-Oxindole Derivatives

A series of new 1,3-dihydro-3-hydroxy-3-(2-phenyl-2-oxoethyl)-2H-indol-2-ones (1a-g) and 1,3-dihydro-3-(2-phenyl-2-oxoethylidene)-2H-indol-2-ones (2a-g) were synthesised by Knoevenagel condensation of substituted indole-2,3-diones (isatins) with various acetophenones. The synthesised compounds were characterised by their physical data, elemental, IR, ¹H NMR, ¹³C NMR and mass spectral analyses and their in vitro antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl free radical scavenging assay. These compounds showed moderate to good antioxidant activities as compared with the standard, ascorbic acid. The antioxidant potential of 3-hydroxy-3-substituted oxindoles (1a-g) increased in a concentration-dependent manner from 10 to 500 μg/ml with 5-fluoro and 5-methyl analogues showing maximum activity. Of 3-aroyl methylene indol-2-ones (2a-g), majority of compounds with halogen substitution at position 5 of isatin ring exhibited good antioxidant activity within a concentration range of 5-100 μg/ml and the maximum activity was observed at 20 and 25 μg/ml concentrations. Thus, our study provides evidence that some newly synthesised isatin derivatives exhibit substantial antioxidant activity at low concentrations.     

何首乌及首乌藤抗氧化活性研究

目的评价何首乌和首乌藤体外总抗氧化活性。方法采用清除二苯代苦味酰基（DPPH）自由基、清除〔2,2′-连氨-（3-乙基苯并噻唑啉-6-磺酸）二氨盐〕（ABTS）自由基和铁离子还原/抗氧化能力（FRAP）测定法。结果将测定结果与水溶性维生素E（6-羟基-2,5,7,8-四甲基苯并二氢吡喃-2-羧酸,Trolox）及阳性对照二丁基羟基甲苯（BHT）进行比较,发现何首乌的乙酸乙酯和甲醇提取物具有较强的清除DPPH自由基、清除ABTS自由基及还原Fe3＋的能力。结论何首乌的总的抗氧化活性好于首乌藤。在6种提取物中,何首乌的乙酸乙酯提取物抗氧化能力最强。同一药用部位,甲醇和乙酸乙酯提取物的抗氧化活性好于石油醚提取物。3种方法之间有很好的相关性,以DPPH法与ABTS法相关性最好（R=0.996）。     

石斛多糖抗氧化活性研究

目的研究石斛多糖的体内、体外抗氧化活性。方法①体外抗氧化实验：用化学反应法检测石斛多糖对邻苯三酚自氧化反应产生的超氧阴离子和Fenton反应产生的羟自由基的清除作用;②体内抗氧化实验：昆明种小鼠随机分为空白对照组、小剂量组、中剂量组和大剂量组,每组10只。研究石斛多糖对小鼠血清及肝组织中SOD、GSH-Px、MDA的影响。结果石斛多糖具有清除羟基自由基和超氧阴离子自由基的作用,可显著提高小鼠血清和肝组织中超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GSH-Px）活力,降低丙二醛（MDA）含量。结论石斛多糖具有明显的抗氧化活性,为进一步开发石斛药材提供依据。