V Attila Molnár

Diterpene Alkaloids from Aconitum anthora and Assessment of the hERG-Inhibiting Ability of Aconitum Alkaloids

A new norditerpene alkaloid, 10-hydroxy-8- O-methyltalatizamine (1), was isolated from the whole plant of ACONITUM ANTHORA L. besides the known isotalatizidine (2) and hetisinone (3). The structures were determined by means of HR-ESI-MS, 1D and 2D NMR spectroscopy, including ¹H-¹H COSY, NOESY, HSQC and HMBC experiments, resulting in complete ¹H and ¹³C chemical shift assignments for 1- 3, and revision of some earlier ¹³C-NMR data. The effects of the isolated compounds, together with twenty-one other ACONITUM alkaloids with different skeletal types and substitution patterns, on hERG channels were studied by the whole-cell patch clamp technique, using the QPatch-16 automated patch clamp system. At 10 µM, aconitine, 14-benzoylaconine 8- O-palmitate, songoramine, gigactonine and neolinine demonstrated significant hERG K+ channel inhibition; all other compounds exerted only low (6-21%) inhibitory activity.

The orchid flora of Turkish graveyards: a comprehensive field survey

Abstract Löki V., Tökölyi J., Süveges K., Lovas-Kiss Á, Hürkan K., Sramkó G. & Molnár V. A.: The orchid flora of Turkish graveyards: a comprehensive field survey. — Willdenowia 45: 231–243. 2015. — Version of record first published online on 17 July 2015 ahead of inclusion in August 2015 issue; ISSN 1868-6397;

Diterpene alkaloids from the roots of Aconitum moldavicum and assessment of Nav 1.2 sodium channel activity of aconitum alkaloids.

A new aconitane alkaloid, 1-O-demethylswatinine (1), was isolated from the root of Aconitum moldavicum together with the known compounds cammaconine (2), columbianine (3), swatinine (4), gigactonine (5), delcosine (6), lycoctonine (7), and ajacine (8). The structures were established by means of HRESIMS, 1D and 2D NMR spectroscopy, including 1H-1H COSY, NOESY, HSQC, and HMBC experiments, resulting in complete 1H-NMR chemical shift assignments for 1-4. The effects of the isolated compounds 4-8, together with eighteen other Aconitum diterpene and norditerpene alkaloids with different skeletal types and substitution patterns, were studied on Nav 1.2 channels by the whole-cell patch clamp technique, using the QPatch-16 automated patch clamp system. Pyroaconitine, ajacine, septentriodine, and delectinine demonstrated significant Nav 1.2 channel inhibition (57-42 %) at 10 µM concentration; several other compounds (acovulparine, acotoxicine, hetisinone, 14-benzoylaconine-8-O-palmitate, aconitine, and lycoctonine) exerted moderate inhibitory activity (30-22 %), while the rest of the tested alkaloids were considered to be inactive. On the basis of these results and by exhaustive comparison of data of previously published computerized QSAR studies on diterpene alkaloids, certain conclusions on the structure-activity relationships of Aconitum alkaloids concerning Nav 1.2 channel inhibitory activity are proposed.

Higher seed number compensates for lower fruit set in deceptive orchids

1.Floral deception is widespread in orchids, with more than one third of the species being pollinated this way. The evolutionary success of deceptive orchids is puzzling, as species employing this strategy are thought to have low reproductive success (less flowers yielding fruits) because of low pollination rates. However, direct measurements of total seed production in orchids – which is a better measure of reproductive success – are scarce due to the extremely small size of their seeds. 2.Here, we quantified seed numbers in 1,015 fruits belonging to 48 orchid species from the Pannonian ecoregion (central Europe) and obtained fruit-set and thousand-seed weight data for these species from the literature. We used phylogenetic comparative methods to test the hypothesis that deceptive species should compensate for their lower fruit-set by having either more flowers, larger seeds or more seeds in a fruit. 3.Similarly to previous studies, we found that deceptive orchids have substantially lower fruits-set than nectar-rewarding ones. Also, we found that deceptive species have more seeds in a fruit but not more flowers or larger seeds compared to nectar-rewarding ones. Based on our results, deceptive species compensate for their lower fruit-set by having higher seed numbers per fruit. As a consequence, their seed numbers per shoot do not differ from that of nectar-rewarding ones. 4.Together with other benefits of deceptive pollination (e.g. lower energy expenditure due to the lack of nectar production and higher genetic variability due to decreased probability of geitonogamous pollination), our results can explain why deceptive strategies are so widespread in the orchid family. 5.Synthesis. Our results indicate that deceptive orchids can compensate for their lower fruit-set by having more (but not larger) seeds in a fruit than rewarding species. These findings highlight possible ways in which plants can increase their reproductive success in face of pollinator limitation. We emphasize that fruit-set in itself is an inappropriate measure of the reproductive success of orchids – the total number of seeds per shoot is a much better approximation.

Flood induced phenotypic plasticity in amphibious genus Elatine (Elatinaceae)

Vegetative characters are widely used in the taxonomy of the amphibious genus Elatine L. However, these usually show great variation not just between species but between their aquatic and terrestrial forms. In the present study we examine the variation of seed and vegetative characters in nine Elatine species (E. brachysperma, E. californica, E. gussonei, E. hexandra, E. hungarica, E. hydropiper, E. macropoda, E. orthosperma and E. triandra) to reveal the extension of plasticity induced by the amphibious environment, and to test character reliability for species identification. Cultivated plant clones were kept under controlled conditions exposed to either aquatic or terrestrial environmental conditions. Six vegetative characters (length of stem, length of internodium, length of lamina, width of lamina, length of petioles, length of pedicel) and four seed characters (curvature, number of pits / lateral row, 1st and 2nd dimension) were measured on 50 fruiting stems of the aquatic and on 50 stems of the terrestrial form of the same clone. MDA, NPMANOVA Random Forest classification and cluster analysis were used to unravel the morphological differences between aquatic and terrestrial forms. The results of MDA cross-validated and Random Forest classification clearly indicated that only seed traits are stable within species (i.e., different forms of the same species keep similar morphology). Consequently, only seed morphology is valuable for taxonomic purposes since vegetative traits are highly influenced by environmental factors.

Typification and seed morphology of Elatine hungarica (Elatinaceae)

A lectotype of the name Elatine hungarica Moesz is designated from Kitaibel’s specimens held in the Hungarian Natural HistoryMuseum in Budapest (BP). Morphological features of seeds of E. hungarica compared with those of the other European taxa of section Elatinella with tetramerous flowers (E. hydropiper, E. gussonei, E. macropoda, E. orthosperma) are provided.

An unexpected new record of the Mediterranean orchid, Ophrys bertolonii (Orchidaceae) in Central Europe

One flowering specimen of Ophrys bertolonii (s. str.) — a plant with a Circum-Adriatic distribution and hitherto unknown in other regions — was found on 7th May 2010 in the vicinity of Kunadacs (Central Hungary; N 47°00′ E 19°17′). The nearest known populations of this Mediterranean plant inhabit the Adriatic coast (ca. 450 km away) in Croatia, therefore this new occurrence represents a significant long distance dispersal event. The circumstances of the occurrence argue against introduction, but we can not decide now whether this new appearance is temporary or permanent. The permanent establishment of this strictly entomophilous plant requires the presence of its specific pollinator in the close neighbourhood of the habitat. However, no pollination was observed on the three flowers of the plant until 9th May, and one day later the stem had disappeared most likely due to grazing. Whatever the long-term fate of the plant is, this discovery represents a significant long distance (jump) dispersal event, and testifies to the dispersal ability of Ophrys species. Additionally, the appearance of a mature Adriatic plant in Central Europe fits well into the currently observed, climate change driven northward expansion of European orchids, therefore this finding most likely reflects a growing Mediterranean-like climatic influence in the region.

Remote, Inland Occurrence of the Oceanic Anogramma leptophylla (L.) Link (Pteridaceae: Taenitidoideae) in Hungary

ABSTRACT The presence of the fern species Anogramma leptophylla was detected in the Zempléni Mountains (NE Hungary) in 1991. The species was known neither from the country nor from the whole Carpatho-Pannonian Region (also known as Carpathian Basin) previously. Its habitat is situated on a roadside bank, cut into an unstable rhyolite surface, above the valley of the Creek Kemence near the village of Pálháza. The fern is a cosmopolitan taxon restricted to humid environments and is considered to be an oceanic-suboceanic (Atlantic) element in Europe. The occurrence in Hungary is located more than 1000 km from the closest populations, thus, this is one of the most remote inland occurrences of this (sub)oceanic species. This striking presence of the fern may be due to the peculiar microclimatological conditions of the habitat, which are described here in order to give an exact explanation for this outstanding occurrence. The chromosomes were also counted in some individuals of the Hungarian population and were found to be n = 26II for each sample.

Molecular phylogenetics, seed morphometrics, chromosome number evolution and systematics of European Elatine L. (Elatinaceae) species

The genus Elatine contains ca 25 species, all of which are small, herbaceous annuals distributed in ephemeral waters on both hemispheres. However, due to a high degree of morphological variability (as a consequence of their amphibious life-style), the taxonomy of this genus remains controversial. Thus, to fill this gap in knowledge, we present a detailed molecular phylogenetic study of this genus based on nuclear (rITS) and plastid (accD-psaI, psbJ-petA, ycf6-psbM-trnD) sequences using 27 samples from 13 species. On the basis of this phylogenetic analysis, we provide a solid phylogenetic background for the modern taxonomy of the European members of the genus. Traditionally accepted sections of this tree (i.e., Crypta and Elatinella) were found to be monophyletic; only E. borchoni—found to be a basal member of the genus—has to be excluded from the latter lineage to achieve monophyly. A number of taxonomic conclusions can also be drawn: E. hexandra, a high-ploid species, is most likely a stabilised hybrid between the main sections; E. campylosperma merits full species status based on both molecular and morphological evidence; E. gussonei is a more widespread and genetically diverse species with two main lineages; and the presence of the Asian E. ambigua in the European flora is questionable. The main lineages recovered in this analysis are also supported by a number of synapomorphic morphological characters as well as uniform chromosome counts. Based on all the evidence presented here, two new subsections within Elatinella are described: subsection Hydropipera consisting of the temperate species of the section, and subsection Macropodae including the Mediterranean species of the section.

Distribution, morphology and habitats of Elatine triandra (Elatinaceae) in Europe, with particular reference to the central part of the continent

Abstract Elatine triandra Schkuhr is the most variable and widespread species within the genus Elatine L.; it has been recorded in all continents, except Antarctica, but it is mainly located in Europe. The study is based on an extensive data set of European literature, herbaria and web data that covers the period 1828–2012. The range of the species in Europe is disjunctive, covering the southern and western parts of the Central European Plain and the southern part of the Fennoscandian Shield. At a smaller scale, the species can also be found along some river valleys. In Central Europe many localities, particularly isolated ones in the northern part of the range, are now only historical. From the data set we determined that E. triandra may be best observed between May and October. We found that species records show a near-significant shift since 1828. Depending on the environmental conditions, individuals of the taxon develop as one of two morphs: terrestrial or aquatic. The aquatic morph is characterized by stems, internodes, lamina and petiole that are twice as long as those of the terrestrial form. Elatine triandra seeds show consistent characteristics, both in terms of morphs and populations. Our studies show that the best diagnostic features, in addition to the construction of flowers, are the size, shape and surface structure of seeds. In Central Europe, E. triandra occurs exclusively in communities classified as Isoëto-Nano-Juncetea.