粗叶悬钩子叶中多酚类与三萜类化合物的研究

采用高效液相色谱-串联质谱（HPLC-MS/MS）联用技术,对中国南方民间用于治疗肝损伤和癌症的药材粗叶悬钩子（Rubus aleaefolius Poir.）叶中的多酚类和三萜类成分进行了分析。通过与文献数据和部分对照品的紫外光谱、负离子模式下的一级和二级质谱信息进行比较,从粗叶悬钩子叶中共分析了18个化合物,鉴定了其中2个多酚类化合物,推测了9个多酚类和7个三萜类化合物的可能结构,并对三萜类化合物的质谱裂解途径进行了解析。基于对三萜类化合物裂解规律的研究,推测了1个三萜,即3-对香豆酰氧基-19α-羟基熊果酸。芦丁、绿原酸和3-对香豆酰氧基-19α-羟基熊果酸在本植物中属首次报道。     

Secondary metabolites from the leaves of Feijoa sellowiana Berg

The investigation of the lipid extract of leaves of Feijoa sellowiana cultivated along the east coast of Sicily has yielded in addition to the widespread secondary metabolites: alpha-tocopherol, flavone, stigmasterol and beta-carotene, an inseparable mixture of tyrosol esters of lignoceric (1a), cerotic (1b) and montanic (1c) acids, and a novel galactolipid identified as (2S)-1,2,6'-tri-O-[(9Z,12Z,15Z)-octadeca-9,12,15-trienoyl]-3-O-beta-D-galactopyranosyl glycerol (2).     

Triterpenoids from Viburnum suspensum

Three triterpenoids, 3-oxo-11,13(18)-oleanadien-28-oic acid, 24-hydroxy-3-oxo-11,13(18)-oleanadien-28-oic acid, 6β-hydroxy-3-oxo-11,13(18)-oleanadien-28-oic acid have been isolated together with the previously known virgatic acid, vibsanin B and 3-hydroxyvibsanin E from the leaves of Viburnum suspensum. Their structures were determined by spectroscopic methods and by comparison of their NMR spectral data with those of the previously known 11,13(18)-oleanadien-3β-ol.     

Clerodane and labdane diterpene glycosides from a Malagasy endemic plant,Cussonia racemosa

Four clerodane glycosides, cussosides A-D, and one labdane glycoside, cussoside E were isolated from the dried leaves of Cussonia racemosa, along with two known flavonol glycosides identified as rutin and kaempferol rutinoside. The structures of the compounds were deduced on the basis of their physical and spectral data.     

Spermine alkaloids from Albizia adinocephala with activity against Plasmodium falciparum plasmepsin II

Crude MeOH extracts from the stem bark and leaves of a Panamanian specimen of Albizia adinocephala (Leguminosae) were found to inhibit the malarial enzyme plasmepsin II. Bioassay guided fractionation led to the isolation of two new bioactive spermine alkaloids, budmunchiamines L4 and L5.     

Triflavonoids of Ochna calodendron

Phytochemical investigation of the dichloromethane extract of Ochna calodendron leaves resulted in the isolation and identification of three known isoflavones, irilone, 3'-methoxyirilone and prunetin, one cyanoglucoside, menisdaurin, in addition to two new triflavonoid constituents, namely caloflavans A and B. The structures of the new compounds were established by spectroscopic methods (EI-MS, FAB-MS, 1H NMR, 13C NMR, HMBC and HMQC).     

Acylated anthocyanins from leaves of Oxalis triangularis

The novel anthocyanins, malvidin 3-O-(6-O-(4-O-malonyl-alpha-rhamnopyranosyl)-beta-glucopyranoside)-5-O-beta-glucopyranoside (2), malvidin 3-O-(6-O-alpha-rhamnopyranosyl-beta-glucopyranoside)-5-O-(6-O-malonyl-beta-glucopyranoside) (3), malvidin 3-O-(6-O-(4-O-malonyl-alpha-rhamnopyranosyl)-beta-glucopyranoside)-5-O-(6-O-malonyl-beta-glucopyranoside) (4), malvidin 3-O-(6-O-(4-O-malonyl-alpha-rhamnopyranosyl)-beta-glucopyranoside) (5) and malvidin 3-O-(6-O-(Z)-p-coumaroyl-beta-glucopyranoside)-5-O-beta-glucopyranoside (6), in addition to the 3-O-(6-O-alpha-rhamnopyranosyl-beta-glucopyranoside)-5-O-beta-glucopyranoside (1) and the 3-O-(6-O-(E)-p-coumaroyl-beta-glucopyranoside)-5-O-beta-glucopyranoside (7) of malvidin have been isolated from purple leaves of Oxalis triangularis A. St.-Hil. In pigments 2, 4 and 5 a malonyl unit is linked to the rhamnose 4-position, which has not been reported previously for any anthocyanin before. The identifications were mainly based on 2D NMR spectroscopy and electrospray MS.     

射干叶中异黄酮类化学成分的研究

从海南产射干叶中分得8个异黄酮类化合物,通过理化常数测定和光谱分析其化学结构分别鉴定为鸢尾黄酮新苷A(iristectorin A,1)、野鸢尾苷(iridin,2)、鸢尾苷(tectoridin,3)、鸢尾苷元(tectorigenin,4)、次野鸢尾黄素(irisflorentin,5)、染料木素(genistein,6)、染料木苷(genistin,7)、樱黄素(Prunetin,8)。所有化合物均为首次从射干叶中分离得到,其中化合物7和8为首次从鸢尾科植物中分离。     

Sea fennel (<Emphasis Type="Italic">Crithmum maritimum</Emphasis> L.) under salinity conditions: a comparison of leaf and root antioxidant responses

The present study was carried out to compare the effect of NaCl on growth, cell membrane damage, and antioxidant defences in the halophyte Crithmum maritimum L. (sea fennel). Physiological and biochemical changes were investigated under control (0 mM NaCl) and saline conditions (100 and 300 mM NaCl). Biomass and growth of roots were more sensitive to NaCl than leaves. Roots were distinguished from leaves by increased electrolyte leakage and high malondialdehyde (MDA) concentration. Superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activities, ascorbic acid (AA) and glutathione (GSH) concentrations were lower in the roots than in the leaves of control plants. The different activity patterns of antioxidant enzymes in response to 100 and 300 mM NaCl indicated that leaves and roots reacted differently to salt stress. Leaf CAT, APX and glutathione reductase (GR) activities were lowest at 300 mM NaCl, but they were unaffected by 100 mM NaCl. Only SOD activity was reduced in the latter treatment. Root SOD activity was significantly decreased in response to 300 mM NaCl and root APX activity was significantly higher in plants treated with 100 and 300 mM compared to the controls. The other activities in roots were insensitive to salt. The concentration of AA decreased in leaves at 100 and 300 mM NaCl, and in roots at 300 mM NaCl, when compared to control plants. The concentrations of GSH in NaCl-treated leaves and roots were not significantly different from the controls. In both organs, AA and GSH were predominating in the total pool in ascorbic acid and glutathione, under control or saline conditions.     

不同季节水杉叶总黄酮含量变化的研究

水杉含有丰富的黄酮成分。用超声提取法制备同一来源、不同季节水杉叶总黄酮样品,以芦丁作标准品,用分光光度法进行了含量测定。结果显示,含量范围为0．970～1．556％,其中以6月份样本的含量最高。初步揭示了水杉叶总黄酮含量随季节变化的规律。