Diallyl di-, tri- and tetrasulphide from Adenocalymma alliaceae

The essential oil from flowers and leaves of Adenocalymma alliaceae (Bignoniaceae) consists almost entirely of diallyl di-, tri-and tetra-sulphide, a mixture formerly encountered within the Allium genus but never before convincingly recognized within the class of dicotyledonous angiosperms.     

大蒜功效成分蒜氨酸的提取与生理活性研究

目的:获取高纯度蒜氨酸并研究其部分功能。方法:采用改进的方法提取蒜氨酸。用体外实验检测其抗菌和抗肿瘤活性。结果:获得了高纯度的蒜氨酸,抑菌实验表明,高纯蒜氨酸对大肠杆菌(Eschrichia coli)、枯草芽孢杆菌(Bacillus subtilis)、金黄色葡萄球菌(Staphylococcus aureus)、痢疾杆菌(Shigella dysenteriae)、幽门螺旋杆菌(Helicobacter pylori)等测试菌株有极强的杀死作用,其MIC分别为4.06×10-3mg/mL、4.06×10-3mg/mL、4.06×10-3mg/mL、8.13×10-3mg/mL、1.63×10-2mg/mL,体外细胞实验结果显示,蒜氨酸对肿瘤细胞人急性早幼粒白血病细胞(HL-60)和人肝癌细胞(H-7402)有很高的抑制和杀死作用。结论:该提取方法适合于大规模生产,蒜氨酸在食品防腐、抗肿瘤药物开发和保健品的研制上有很好的应用潜力和应用前景。     

(2R)-Catalponone,a biosynthetic intermediate for prenylnaphthoquinone congeners of the wood of Catalpa ovata

In accord with the results of experiments using callus tissues of Catalpa ovata, the simultaneous administration of (2R)- [1-¹⁴C]catalponone and (2S)- [8-³H]catalponone to the wood of the same plant demonstrated that the main pathway for the biosynthesis of naphthoquinone congeners, including catalpalactone, catalponol and 4,9-dihydroxy-α-lapachone, proceeds through the 2R-enantiomer of catalponone.     

A new taxon in the genusMoehringia (Caryophyllaceae)

The new taxonMoehringia intricata subsp.giennensis, from the calcareous mountains of the south-eastern Iberian Peninsula is described. A comparative morphological study with regard to the most closely related taxa, contributes information of leaf anatomy, seed and pollen morphology, ecology and distribution.     

角蒿属(紫葳科)的花粉形态

对角蒿属(Incarvillea Juss.)14个种(4变种,2居群)的花粉进行了扫描电镜观察。角蒿属花粉形态较为相似,为单粒花粉,花粉粒扁球形至近球形,外壁表面同时具有近刺状和穴状两种纹饰。大小在28～51μm之间,萌发孔为多沟型,6～10沟,沟长度不等,沿赤道分布,一些种类中沟多少弯曲使萌发孔成螺旋状,沟末端在极面上多少连接形成合沟。角蒿属内种间花粉形态上的相似性说明了角蒿属应为一单系类群,而对于角蒿属下单元划分及种间的系统有着有限的意义,波罗花亚属花粉明显大于其它两个属,花粉形态特征也显示了它与角蒿亚属关系较近。同时,研究结果不支持将角蒿属放在硬骨凌霄族(Tecomeae)。     

The north-east-Brazilian Liana, Adenocalymna dichilum (Bignoniaceae) pollinated by bats

BACKGROUND AND AIMS: Of the set of syndromes displayed by specialized (euphilic) flowers, adaptation to pollination by bats (chiropterophily) is the least known. Accumulated new evidence reveals that this pollination mode plays a considerable role in tropical communities, especially in the neotropics. One family in which bat-pollinated species are known in several genera is the Bignoniaceae. Here is reported, for the first time, bat pollination and floral ecology in Adenocalymna dichilum (tribe Bignonieae). METHODS: Floral features of this species growing in Bahia (north-east Brazil) indicated possible chiropterophily, which was subsequently confirmed by direct observation and from photographs of bat visits. Timing of anthesis and nectar parameters were monitored in the field, and floral morphology was investigated with fixed flowers. KEY RESULTS: One to two flowers open per night on the upright, simple racemes of A. dichilum during several weeks in a 'steady state' mode. The bilabiate, cream-coloured corollas are functional for only a single night and wilt during the following day. A stout corolla, with a musky odour, and a large nectary disc with large quantities of watery nectar also conform to the syndrome. Glossophaga soricina (Glossophaginae) visited and pollinated the flowers in a trap-lining manner. Whilst hovering, the bats put their heads into the corolla mouth for less than 1 s to feed, thereby effecting the transfer of pollen which is deposited on their backs. CONCLUSIONS: Adenocalymna, a New World genus comprising approx. 50 species, exhibits floral adaptive radiation including species pollinated by bees, birds and possibly moths. The discovery of chiropterophily in A. dichilum adds another facet to the array of floral syndromes represented in the genus.     

Pollination of Adenocalymma bracteatum (Bignoniaceae): floral biology and visitors

Adenocalymma bracteatum is a shrub of dense foliage and yellow flowers, easily found on grasslands areas in Central Brazil. The aim of this study was to determine the reproductive biology and the flower visitors of A. bracteatum in a pasture area nearby Ivinhema city, MS (Brazil). The flowering peak occurs in winter. The flower reflects ultraviolet light. Anthesis begins at 6:30h, and pollen and nectar are the resources to visitors. We captured 1,038 floral visitors. The bees Apis mellifera (L.), Trigona sp., Trigona spinipes (Fabricius), (Hymenoptera: Apoidea) and the ant Cephalotes sp. (Hymenoptera: Formicidae) were the main visitors. The reproductive tests indicate that A. bracteatum is self compatible, justifying its expansion in altered environments; however, the largest reproductive success was dependant on cross-pollination and self-pollination, evidencing the pollinators importance. Adenocalymma bracteatum presents melittophilous syndrome and bumblebees were the main pollinators in the area. The correlations observed between the climatic variables and the main pollinator species were low or medium.     

Alliin lyase localization in bundle sheaths of the garlic clove (Allium sativum)

The enzyme alliin lyase (E.C. 4.4.1.4) catalyzes formation of allicin, the parent of several sulfur-containing compounds responsible for flavor, odor, and pharmacological properties of garlic (Allium sativum). Alliin lyase is a major product of the storage bud (clove), accounting for 10% of its total protein. Accumulation of this protein was characterized by locating alliin lyase deposits within the clove. Paraffin sections stained for general protein using aniline blue-black reveal dense deposits within parenchymatous bundle sheaths. Deposits are most pronounced around phloem. Remaining storage parenchyma, not in contact with bundles, appears structurally uniform, with some protein accumulating in cells near the outer surface of the clove. In freehand sections of unfixed cloves, bundle sheath cells are the only ones to show green autofluorescence when excited by blue light. Such fluorescence is consistent with the presence of pyridoxal phosphate cofactor of alliin lyase. An alliin lyase activity stain, based on detecting aminocrotonate-generating enzymes, shows activity to be restricted to bundle sheath cells in fresh material. Finally, enrichment of alliin lyase in bundle sheaths is shown by immunocytochemical staining of these areas using a polyclonal antibody generated against purified enzyme. Aliin lyase concentrates in bundle sheaths, while little if any occurs in storage mesophyll not in contact with vascular bundles. Deposits in the cloves may reflect the enzyme's role in protecting underground storage buds from decay and predation. Positioning near the phloem suggests that alliin lyase, or compounds related to its metabolism, may be translocated to and from the clove during development.     

Development and characterization of microsatellite markers for the tropical tree species Tabebuia aurea (Bignoniaceae)

In this study, we report the development and characterization of 21 polymorphic microsatellite loci for Tabebuia aurea, using genomic library enrichment. Number of alleles per locus and expected heterozygosity ranged from nine to 26 and from 0.808 to 0.955. The high combined probability of genetic identity (1.03 × 10^?37) and probability of paternity exclusion (0.9889) showed that multilocus genotypes are likely to be unique and will allow detailed parentage studies in natural populations of T. aurea. Additionally, a high percentage of transferability was achieved for the four species of the same genus studied.     

Larvicidal activity of Pseudocalymma alliaceum and Allium sativum against Culex quinquefasciatus (Say)

The larvicidal activity of the plant extracts Pseudocalymma alliaceum and Allium sativum were determined against Culex quinquefasciatus. The hexane extract of P. alliaceum and the petroleum ether extract of A. sativum exhibited larvicidal efficacy against Cx. quinquefasciatus larvae. Extracts of P. alliaceum resulted in concentrations that produced 50% mortality LC₅₀ and LC₉₀ values of 2.49 and 15.06 ppm, respectively, after 24 h and 1.16 and 8.45 ppm after 48 h. Extracts of A. sativum resulted in LC₅₀ and LC₉₀ values of 8.38 and 29.15 ppm after 24 h and 7.28 and 44.19 ppm after 48 h of exposure, respectively. The results indicate that the plant extract component(s) present in the hexane extract of P. alliaceum leaves demonstrated greater potential as an efficient larvicide than A. sativum against Cx. quinquefasciatus.     

Phenolic acid glycosides from Parmentiera cereifera Seem. (Candle tree)

Two new phenolic acid glycosides, parmentins A (1) and B (2) were isolated from the methanolic extract of the leaves and stems of candle tree (Parmentiera cereifera Seem). These compounds were accompanied by a mixture of β-sitosterol and stigmasterol (3), β-sitosterol glucoside (4), isovanillic acid (5), vanillic acid (6), and p-hydroxybenzoic acid (7). The structures of the isolated compounds were determined on the basis of physical and spectroscopic analyses, including 1D and 2D NMR (¹H, ¹³C, COSY, HSQC and HMBC) and mass spectrometry (HR-ESI-MS).     

A naphthoquinone and a lignan from the wood of Kigelia pinnata

A new naphthoquinone, kigelinone, and a new lignan, kigeliol, together with six known constituents including lapachol and dehydro-α- lapachone, were isolated from the wood of Kigelia pinnata. On the basis of spectral data and chemical degradations, kigelinone was characterized as 2-(1-hydroxyethyl)-8-hydroxy-naphtho[2,3-b]furano-4,9-dione and kigeliol as (2S,6S)-bis(3,4-methylenedioxyphenyl)- 3,7- dioxabicyclo[3.3.0]octan-1R,5R-diol or its enantiomer.     

Bioleaching of metallic sulphides withThiobacillus ferrooxidans in the absence of iron (II)

Bioleaching of metallic sulphides withThiobacillus ferrooxidans in the absence of iron (II) was studied using pure sulphides and mixtures. The direct mode of bacterial action was analysed with respect to sulphide solubility, exposed solid surfaces and bacterial attachment to the solids. Bioleaching of mixed sulphides showed enhancement of metal extraction in comparison with pure sulphides which suggests metal extractions would be better from polymetallic sulphide ores than from similar matrices with only one sulphide.     

An extinct Eocene taxon of the daisy family (Asteraceae): evolutionary, ecological and biogeographical implications

Background and Aims

Morphological, molecular and biogeographical information bearing on early evolution of the sunflower alliance of families suggests that the clade containing the extant daisy family (Asteraceae) differentiated in South America during the Eocene, although palaeontological studies on this continent failed to reveal conclusive support for this hypothesis. Here we describe in detail Raiguenrayun cura gen. & sp. nov., an exceptionally well preserved capitulescence of Asteraceae recovered from Eocene deposits of northwestern Patagonia, Argentina.

Methods

The fossil was collected from the 47·5 million-year-old Huitrera Formation at the Estancia Don Hipólito locality, Río Negro Province, Argentina.

Key Results

The arrangement of the capitula in a cymose capitulescence, the many-flowered capitula with multiseriate–imbricate involucral bracts and the pappus-like structures indicate a close morphological relationship with Asteraceae. Raiguenrayun cura and the associated pollen Mutisiapollis telleriae do not match exactly any living member of the family, and clearly represent extinct taxa. They share a mosaic of morphological features today recognized in taxa phylogenetically close to the root of Asteraceae, such as Stifftieae, Wunderlichioideae and Gochnatieae (Mutisioideae sensu lato) and Dicomeae and Oldenburgieae (Carduoideae), today endemic to or mainly distributed in South America and Africa, respectively.

Conclusions

This is the first fossil genus of Asteraceae based on an outstandingly preserved capitulescence that might represent the ancestor of Mutisioideae–Carduoideae. It might have evolved in southern South America some time during the early Palaeogene and subsequently entered Africa, before the biogeographical isolation of these continents became much more pronounced. The new fossil represents the first reliable point for calibration, favouring an earlier date to the split between Barnadesioideae and the rest of Asteraceae than previously thought, which can be traced back at least 47·5 million years. This is the oldest well dated member of Asteraceae and perhaps the earliest indirect evidence for bird pollination in the family.     

Floral sources used by the orchid bee Euglossa cordata (Linnaeus, 1758) (Apidae: Euglossini) in an urban area of south-eastern Brazil

Although orchid bees (Apidae: Euglossini) are known as key pollinators in tropical ecosystems, knowledge of their floral sources is still scarce, especially for those species commonly found in urban environments. We aimed to identify the pollen, nectar and resin sources used by the widespread species Euglossa cordata in an urban area in south-eastern Brazil. The residual pollen from 81 brood cells of nine nests reactivated between October 2013 and December 2014 was acetolysed and analysed. A total of 50 pollen types belonging to 20 botanical families were identified in the samples. Pollen sources included species from seven families; five of them were plants with poricidal anthers (Bixaceae, Commelinaceae, Fabaceae, Melastomataceae and Solanaceae). The mass-flowering trees Handroanthus chrysotrichus and H. heptaphyllus (Bignoniaceae) are firstly reported as important pollen sources to an orchid bee species. Nectar was collected primarily from plants with long, tubular corolla as Acanthaceae, Apocynaceae, Bignoniaceae and Convolvulaceae. The vine species Dalechampia stipulacea (Euphorbiaceae) acted as a floral resin source. All pollen sources consisted of native plants whereas some exotic plant species were visited for nectar collection. Although nesting in an area encompassed by a high proportion of invasive plant species, Euglossa cordata females preferred to visit native plants to gather floral resources.     

Jacoumaric acid,a new triterpene ester from Jacaranda caucana

Jacoumaric acid isolated from Jacaranda caucana is shown to be 2α-hydroxy-3β-trans-p-coumaryloxy-urs-12-en-28-oic acid.     

蒜香藤叶挥发油的化学成分

蒜香藤（Pseudocalymma alliaceum Sandw．）又名紫铃藤,为紫葳科（Bignoniaceae）常绿藤状灌木,原产于南美洲的圭亚那和巴西。蒜香藤花、叶在搓揉之后,有浓浓的大蒜香味,其叶深绿富有光泽,花形大而优美,中国许多地方已引种栽培,一般作为篱笆、围墙美化或凉亭、棚架装饰之用。蒜香藤具有浓郁的蒜香,甚至可作为蒜的替代物用于烹饪。但有关其叶挥发性成分研究尚未见报道。本文利用气相色谱-质谱联用技术（GC—MS）分析了西双版纳植物园引种栽培的蒜香藤叶挥发油的化学成分,以期为合理开发和利用蒜香藤植物资源提供科学依据。     

Festuca rohlenae (Poaceae): A neglected taxon of the Montenegro

Abstract

Festuca porcii var. angustifolia is raised to the rank of a species under the new name F. rohlenae. It is an endemic of SE Dinarides in Montenegro, and it is most similar to the Carpathian F. porcii. Both species have the “broad‐leaved syndrome” and exhibit an intermediacy between “fine‐leaved” and “broad‐leaved” fescues. The comparative morpho‐anatomical data and the distribution map as well as basic ecological information of F. rohlenae are herewith presented.