Volatile constituents of Aristolochia argentina

The essential oils from leaves, aerial stems and underground organs of Aristolochia argentina Gris., a medicinal plant popularly known as "charrúa", were obtained by hydrodistillation and analyzed by GC and GC/MS. Forty-three components were identified in the oils. All parts of the plant afforded volatile oils characterized by high levels of argentilactone (57-89%) and the presence of undecatriene isomers (0.3-4.0%), these latter compounds providing the essential oils and extracts with an intense particular odor. Terpenes account for the remaining portion of the essential oils (5-29%). Bicyclogermacrene predominates in the aerial parts of the plant, whereas ishwarane is the main terpene of the subterranean organs. Argentilactone, a suspected carcinogenic compound, was also identified in a medicinal commercial tincture of A. argentina.     

金沙江流域4种特有植物野生资源现状及受威胁等级评估

物种受威胁状况的及时评估是调整物种濒危状态,继而实施有效保护措施的重要依据。该文以金沙江流域特有植物贯叶马兜铃(Aristolochia delavayi)、旱地木槿(Hibiscus aridicola)、云南百部(Stemona mairei)和白魔芋(Amorphophallus albus)为调查评估对象,通过多年野外调查,依据《IUCN物种红色名录等级和标准: 3.1版》和《使用指南: 15.1版》对4物种的濒危现状进行了重新分析和评估。结果表明,在现有野生种群资源下贯叶马兜铃被列为易危(VU),旱地木槿和白魔芋被列为濒危(EN),云南百部为近危(NT)。与4物种现行濒危等级的比较表明,贯叶马兜铃的濒危等级由濒危降级为易危,旱地木槿由易危上调为濒危,白魔芋由近危上调为濒危,云南百部的濒危状态则维持不变。这为4种特有植物的野生资源现状了解、濒危状态更新以及适时调整有效保护策略提供了科学参考。     

Genecological notes on Allium schoenoprasum L.

Summary

Ajuga pyramidalis is a polycarpic, perennial herb which is variable in flowering and population size. It has been recorded from over 200 sites in the Highlands and Islands of Scotland, one in the Lake District and in twelve coastal sites in Ireland. It grows mainly on circum-neutral soils (pH 4.9–6.9) in open grassland and heathland, and upland rock ledges. It does not appear to be under any particular threat in Britain.     

马兜铃不含腋芽茎段不定芽的诱导

为建立马兜铃(Aristolochia debilis Sieb.et Zucc)不含腋芽茎段的不定芽诱导体系,采用正交设计方法研究植物生长调节剂、预培养方式和AgNO3对不定芽诱导的影响。结果表明:植物生长调节物质对不定芽诱导的影响以TDZ6-BAIAA,其中TDZ的影响极显著(P0.01),6-BA的影响显著(P0.05)。不定芽诱导的最适培养基为MS+0.5 mg L–1 TDZ+0.1 mg L–1IAA+0.5 mg L–1 6-BA+2 mg L–1 AgNO3+3%蔗糖+0.6%琼脂(pH 5.8);预培养方式为在MS+0.1 mg L–1 2,4-D+3%蔗糖+0.6%琼脂培养基上暗培养2 d。马兜铃不含腋芽茎段的不定芽诱导率最高可达37.5%。     

Tetraflavonoid and biflavonoids from Aristolochia ridicula

Biflavones, a chalcone-flavone, and a tetraflavonoid with a new carbon skeleton were isolated from the leaves of Aristolochia ridicula. Their structures were determined by chemical derivatizations and spectrometric analyses.     

Micropropagation of Aristolochia rotunda L.

An original protocol of micropropagation of Aristolochia rotunda L., an important herb for the survival of an endangered butterfly was developed. The cytokinin 6-benzylaminopurine affected the production of new shoots but had no effect on shoot length. The addition of indole-3-butyric acid (IBA) had a negative effect on shoot length. Best results in terms of rooting percentage and root length were achieved with 1.5 μM IBA. The protocol can be employed to enhance the number of A. rotunda in the environment.     

II gruppo Aristolochia pallida nell'Italia nordorientale

Abstract

The Aristolochia pallida group in the north-eastern Italy. The Aristolochia pallida group includes two closely related species: A. pallida Willd. and A. lutea Desf. For each species, a biometrical-morphological analysis on selected characters and critical notes are given. The distribution of both species in the north-eastern Italy is also defined.     

Microsporogenesis and systematics of Aristolochiaceae

Within Aristolochiaceae, a secretory tapetum and orbicules are ubiquitous, but both simultaneous and successive types of microsporogenesis occur. Simultaneous cytokinesis is apparently plesiomorphic within the order Piperales, in which Aristolochiaceae are now placed. Successive microsporogenesis was found only in species of Aristolochia confined to a crown clade in the proposed phylogeny of this genus. In contrast to many other taxa, within Aristolochiaceae there is no strict relationship between microsporogenesis type and tetrad configuration, which is strongly influenced by spindle orientation, especially during meiosis II. There is also no direct correlation between microsporogenesis type and the aperture of mature pollen grains.     

变色马兜铃化学成分的研究

从变色马兜铃块根乙醇提取物的石油醚溶解部分中分得一个倍半萜内酯(B_2),分子式C_(15)H_(20)O_2,熔点94—95℃,[α]_D~(36)-49°(C=1.8,EtOH)。通过光谱分析和化学反应测定了结构,并证明它与异马兜铃内酯(isoaristolactone)为同一化合物,从而使异马兜铃内酯的结构得以明确。B_2系首次从植物中分到。另从石油醚不溶部分中分得12个成分(D_1—D_3,D_(4f),D_(4y),D,—D_(10)和 C_2)。其中7个分别鉴定为6-甲氧基去硝基马兜铃酸甲酯(D_1)、去硝基马兜铃酸(D_3)、6-甲氧基去硝基马兜铃酸(D_(4f))、6-甲氧基马兜铃酸甲酯(D_(4y))、马兜铃酸A(D_5)、β-谷甾醇-D-葡萄糖甙(D_(10))和尿囊素(C_2)。D_(4f)亦系首次从植物中分到。动物试验表明,D_1、D_3和 D,均有明显的抗生育活性。