Negatively charged flavones and tricin as chemosystematic markers in the palmae

A survey of 125 species of the Palmae revealed a complex pattern of flavonoids in the leaf. C-Glycosylflavones, leucoanthocyanins and tricin, luteolin and quercetin glycosides were common, being present in 84, 66, 51, 30 and 24% of the species respectively. Apigenin and kaempferol were recorded in only a few species and isorhamnetin only once. Eighteen flavonoids were identified: the 7-glucoside, 7-diglucoside and 7-rutinoside of both luteolin and tricin, tricin 5-glucoside, apigenin 7-rutinoside, quercetin 3-rutinoside-7-galactoside, isorhamnetin 7-rutinoside, orientin, iso-orientin, vitexin, isovitexin and vitexin 7-O-glucoside. Many of the C- and O-flavonoid glycosides were present as the potassium bisulphate salts and negatively charged compounds were detected in 50% of the species. The distribution patterns are correlated with the taxonomy of the family in several ways. Thus, the Phoenicoideae and Caryotoideae have distinctive flavonoid patterns, there is evidence to support the separation of the subfamilies Phytelephantoideae and Nypoideae, and tricin is a useful marker at tribal level. At the generic level, Cocos is clearly separated from Butia, and other Cocoseae and Mascarena and Chamaedorea form well defined groups within the Arecoideae. A numerical analysis of these biochemical data, together with morphological characters, produces a new classification which suggests that the flavonoid data may have more systematic value than is indicated when they are applied to the traditional classification.     

Species-specific kaempferol derivatives in ferns of the appalachian Asplenium complex

A series of kaempferol derivatives have been identified in fronds of three parental species of the Appalachian Asplenium complex. Asplenium platyneuron is characterised by the presence of the 7-glucoside of kaempferol 3,4′-dimethyl ether and also contains kaempferol 3,7-diglucoside, free and with an aliphatic acyl attachment. By contrast, A. rhizophyllum contains a remarkable caffeoyl complex of kaempferol glycosides, which appears to be chromatographically homogenous. However, on deacylation, the complex yields caffeic acid and the 7-glucoside, 3,7-diglucoside, 3-sophoroside-7-glucoside and 7,4′-diglucoside of kaempferol. Asplenium montanum, in addition to having previously characterised glycosylxanthones, has two further kaempferol derivatives. It has been confirmed that these various species specific flavonoids are inherited in an additive fashion in three interspecific hybrids.     

Isolation and synthesis of two new flavones from Conoclinium coelestinum

Two new flavones, 3′,4′-methylenedioxy-5,6,7,8,5′-pentamethoxyflavone and 5,7,4′-trihydroxy-6,3′,5′-trimethoxyflavone, have been isolated from Conoclinium coelestinum. Final structure proof was accomplished by synthesis.     

五种丛生状棕榈植物叶热值的月变化研究

对5种丛生状棕榈植物一欧洲棕、细叶棕竹、小箬棕、玲珑椰子、缨络椰子的叶片热值和灰分含量的月变化进行了研究,结果表明,5种植物具有较高的灰分含量,但灰分含量的月变化趋势各不相同;欧洲棕、细叶棕竹、小箬棕3种植物干重热值的月变化趋势有些差异,同属的缨络椰子、玲珑椰子干重热值的月变化趋势基本相似;缨络椰子、小箬棕的干重热值与灰分含量具有显著的线性相关(P<0．05),而其余3种植物的干重热值与灰分含量相关性不显著(P>0．05);从去灰分热值的月变化来看,细叶棕竹与小箬棕,缨络椰子与玲珑椰子的月变化趋势相似。     

Distribution of flavonoids and their systematic significance in Clematis subsection Viornae

Fifteen flavonoids were identified in the eight taxa of Clematis subsection Viornae. Flavonols, flavones, and C-glycosyl flavones were present. The compounds were based primarily on luteolin, apigenin, quercetin, and kaempferol. The systematic significance of the distribution of these compounds among the taxa is discussed.     

Flavonoid chemistry of Chenopodium fremontii. Infraspecific variation and systematic implications at the interspecific level

Four flavonoid geographical races based on twenty flavonol 3-O-glycosides were found to exist in Chenopodium fremontii with those populations from the northern part of the range (northern Colorado, Wyoming. and western Nebraska) producing 7-methyl ethers and 3-O-galactosides and glucosides. Plants from Arizona. southern Colorado and New Mexico lack 7-methyl ethers and contain 3-O-rhamnogalactosides and rhamnoglucosides (rutinosides). California populations are chemically similar to those from Arizona, southern Colorado and New Mexico but contain arabinosides while lacking rutinosides. No morphological features could be correlated with the chemical races. Chenopodium fremontii can be distinguished chemically from other closely related diploid species of the western U.S., all of which exhibit simpler flavonoid patterns. It is suggested that the simpler chemical patterns for the latter species (which include C. atrovirens, C. desiccatum, C. hians. C. incanum, C. leptophyllum, and C. pratericola) are a derived condition relative to C. fremontii.     

我国的野生棕榈科园林观赏植物资源

我国原产棕榈科植物约有 18属 10 0种 ,可用于园林绿化及观赏的有 12属 4 4种 ,可作行道树、园景树、庭园树、室内观赏树和海滨、沙滩绿化树。虽然资源不太丰富、分布范围较为狭窄 ,但观赏价值较高 ,许多为国家重点保护植物。本文还重点介绍了部分种类 ,并对开发利用提出了建议     

中国分类学文献中Livistona saribus 之订正

通过调查,对Livistona speciosa的等模式、L.saribus的等新模式与中国分类学文献中（如《海南植物志》、《中国植物志》、《福建植物志》、《云南植物志》）的L.speciosa、L.saribus作比较,证实中国分类学文献将L.saribus、L.speciosa相混,中国分类学文献中的L.saribus、L.speciosa均为L.speciosa Kurz。美丽蒲葵L.spe-ciosa的叶的裂片先端浅裂、坚挺,果倒卵形、椭圆形至卵形,长度多于2.5cm,直径多于2cm;大叶蒲葵L.sari-bus（Lour.）Merr.ex A.Chev.的叶的裂片先端深裂、下垂,果球形至近球形,直径少于1.8cm。增补了L.sari-bus的等新模式。     

Occurrence of sulphated flavones and caffeic acid esters in members of the fluviales

A survey of 50 species of the Fluviales showed that over 50% have either flavone or caffeic acid sulphates present. Flavone sulphates were detected in 16% of the sample and the 7-sulphates of luteolin, apigenin, diosmetin and chrysoeriol and the 7,3′-disulphate of luteolin were identified variously in Thalassia, Zannichellia and Zostera species. Anionic caffeic esters were found in 46% of the sample; preliminary studies indicate the presence of sulphated caffeylquinic acids in these plants. In confirmation of earlier studies, glycoflavones were found to be widespread and flavonols and proanthocyanidins to be rare. The taxonomic and ecological significance of these results are discussed.     

扁蓄总黄酮提取方法的比较

The factors which effected the extraction of total flavones from Polygonum aviculare L.var.aviculore were discuseed with respects to solvent,concentration and the extracting temperature.The rutin was used as a standard compound,the total flavones extracted by the different extracting procedure were quantitated by measurement of absorbance at 510 nm.The results show that 80℃ and 35% alcohol are optimal and the extracting rate of the total flavones in as high as 4.349%.     

GC-MS identification of abscisic acid and abscisic acid metabolites in seed of Vigna unguiculata

Abscisic acid, phaseic acid and 4′-dihydrophaseic acid were identified by GC-MS of derivatized (Me, MeTMSi) extracts from immature fruits of Vigna unguiculata. The fruits also contained some other ABA-related compounds, one of which might be epi-4′-dihydrophaseic acid while another was tentatively identified as 6′-hydroxymethylabscisic acid.     

3个三角梅品种中类黄酮的毛细管电泳分析比较研究

甜菜色素和属于类黄酮的花青素在自然界排斥分布,然而我们在甜菜色素代谢类型植物三角梅中发现积累多种类黄酮。为了进一步证实这一现象,本研究对3种白花三角梅（Bougainvillea sp.,Bougainvillea glabra‘Alba’,and Bougainvillea‘White Stripe’）中的5种类黄酮（槲皮素、山奈酚、异鼠李素、杨梅素和芹菜素）采用毛细管电泳分析方法进行了调查。结果表明,只有3种类黄酮：槲皮素、山奈酚、异鼠李素被检测出。3个材料中,被探测出来的总黄酮含量最高的是Bougainvillea glabra‘Alba’,1 749 μg·g^-1,Bougainvillea‘White Stripe’ 1 241 μg·g^-1以及B.sp1 312 μg·g^-1。被探测出来的3种黄酮中,槲皮素含量最高852～1 114 μg·g^-1,异鼠李素161～628 μg·g^-1,而山奈酚之被检测出微量。本研究对于定性定量可食用的三角梅中的类黄酮组成是十分有意义的。甜菜色素和类黄酮在三角梅中的积累关系以及可能的功能本研究也做了讨论。     

The biosynthesis of abscisic acid in Cercospora rosicola

1′-Deoxyabscisic acid (1′-deoxy-ABA) has been isolated from cultures of Cercospora rosicola which are actively synthesizing abscisic acid (ABA)     

Batudioic acid and flavonoids from Baccharis tucumanensis

Batudioic acid, a new labdane type diterpene, was isolated from aerial parts of Baccharis tucumanensis. Its structure was determined by spectral analysis and some chemical transformations. Xan- thomicrol and scutellarein-7,4′-dimethyl ether were also isolated.     

杜仲雄花中次生代谢物合成积累的动态变化

对杜仲(Eucommia ulmoides Oliv.)雄株不同花期雄花中次生代谢产物含量进行分析测定,并对杜仲雄花次生代谢的生理基础及不同花期次生代谢产物含量差异进行了探讨.研究结果表明,雄花在不同花期次生代谢产物含量均有差异.总黄酮含量在花蕾期最高(4.010%),始花期最低(2.422%),从盛花期到末花期逐渐上升;桃叶珊瑚苷和绿原酸含量均在花蕾期最高(分别为2.351%和1.075%),盛花期最低(分别为1.463%和0.503%),至末花期含量上升;京尼平苷酸含量在始花期最低(0.217%),从盛花期开始逐渐升高,至末花期高达1.403%;次生代谢产物总量也以花蕾期为最高(7.420%).杜仲雄花的花蕾期和盛花期是兼顾质量和产量的最佳采摘期.     

Effect of 3,4-dihydroxyacetophenone and some related phenols on the peroxidase-catalysed oxidation of indole-3-acetic acid

3,4-Dihydroxyacetophenone, 3,4-dihydroxypropiophenone and acetovanillone differed in activity in the enzymic oxidative reaction of indole-3-acetic acid     

Distribution of aromatic l-amino acid decarboxylase in tissues of skipjack tuna using l-DOPA as the substrate

Aromatic L-amino acid decarboxylase activity was measured in brain, heart, intestine, kidney, liver, muscle, pyloric caeca, spleen and stomach of skipjack, using L-3,4–dihydroxyphenylalanine as the substrate. Aromatic L-amino acid decarboxylase activity was found to be present in all of the organs studied. The highest activity was found in the intestine (1774 μmol min ⁻¹ g⁻¹ wet wt of tissue). The liver showed the lowest activity (48.7 umol min ⁻¹ g ⁻¹).     

CV and NMR study on the reaction of Mo(VI) with 3,4-dihydroxybenzoic acid and ascorbic acid in aqueous solution

The gradual release of the ligand 3,4-dihydroxybenzoic acid (3,4-DHBA) from its molybdenum complex in the presence of ascorbic acid (AscA) in a weakly acidic aqueous solution (pH ∼ 3.5) is described. We observed that the formation of the 3,4-DHBA-semiquinone oxidation state and the semidehydroascorbate is a pre-requisite for the release of the 3,4-DHBA ligand. The interaction of these radicals leads at the same time to the further degradation of AscA resulting in, among other compounds, threonic acid which participates in the reaction with molybdenum. The comparison of the complexing ability indicated that threonic acid competes with protocatechuate, while ascorbic acid is a less good ligand for the Mo(VI). Solution studies on the reaction mechanism were performed by cyclic voltammetry, NMR spectroscopy and UV-Vis spectroscopy. Isolated precipitates were investigated by NMR spectroscopy. The antioxidant properties of 3,4-DHBA and AscA were also compared using the stable radical 2,2-diphenyl-1-picrylhydrazyl (DPPH).     

The fluorescence enhancement of quercetin–nucleic acid system and the analytical application

Nucleic acid can greatly enhance the fluorescence intensity of quercetin in HMTA‐HCl (pH 5.5) buffer. The enhanced intensity is in proportion to the concentration of nucleic acids in the range 5.0 × 10^?9 to 1.0 × 10^?6 g/mL for fsDNA, 5.0 × 10^?9 to 7.0 × 10^?7 g/mL for ctDNA and 5.0 × 10^?9 to 1.0 × 10^?6 g/mL for yRNA, and their detection limits (S/N = 3) are 3.5 × 10^?9, 7.8 × 10^?10 and 2.6 × 10^?9 g/mL, respectively. In comparison with most reported fluorescent probes for the determination of nucleic acids, the proposed probe has higher sensitivity and lower toxicity. The interaction investigation indicates that quercetin binds with double‐strand DNA in groove binding mode, resulting in fluorescence enhancement of this system. Copyright © 2009 John Wiley & Sons, Ltd.