Novel Ecdysteroids from Serratula wolffii

Two new and one known ecdysteroids were identified in the methanolic extract of the roots of Serratula wolffii. The new compounds isolated were ponasterone A-22-apioside (1) and 3-epi-shidasterone (3), together with the known 3-epi-22-deoxy-20-hydroxyecdysone (2). The structures of compounds 1–3 were determined by extensive spectroscopic techniques, including one- and two-dimensional NMR methods

Ínfű fajok és a lucerna másodlagos kémiai anyagai és hatástani vizsgálatai rovarokon = Allelochemicals from alfalfa and Ajuga plants and those of biological activity on different insect orders

Különböző Ajuga fajok teljes növényi őrleményét (Plodia interpunctella), teljes és frakcionált metanolos kivonatait (Acyrthosiphon pisum, Dysdercus cingulatus, Aedes aegypti, Daphnia magna), valamint tisztított ekdiszteroidok hatékonyságát vizsgáltuk. A Plodia-teszben az A. reptans 8 %-os dózisa azon túl, hogy kétszeresére növelte a posztembrionális kifejlődéshez szükséges időt és csökkentette a bábok súlyát - számottevő mortalitást (77 %) is okozott. Az A. aegypti esetében jelentős hatékonyságot csak az A. reptans 100%-os metanolos frakciója mutatott (0,1 %-os dózisban ~80 %-os mortalitás). A szívó szájszervű rovaroknál (A. pisum, D. cingulatus) A. chamaepitys 100%-os és az A. bracteosa 60%-os frakciói bizonyultak a leghatékonyabbak (0,1 %-os koncentrációban 100 %-os mortalitás). A tisztított ekdiszteroidok közül a 20E és a Polipodin B voltak hatékonyak a levéltetű tesztben (LC50 = 1,07 és 0,21 ppm). Az A. reptans-ból 10 különböző ekdiszteroidot (20-hidroxiekdizon, 20-hidroxiekdizon 3-acetát, ciaszteron, ciaszteron 3-acetát, 29-nor-ciaszteron, ajugaszteron B', ajugalakton, szengoszteron, 23-hidroxi-kapitaszteron, 24-etil-24,26-dihidroxi-taxiszterol 26-metilát) sikerült izolálnunk. Ezek közül két vegyület (23-hidroxi-kapitaszteron, 24-etil-24,26-dihidroxi-taxiszterol 26-metilát) új természetes ekdiszteroidnak bizonyult. Az A. reptans-ból eddig izoláltak közül a 20-hidroxiekdizon 3-acetátot és a ciaszteron 3-acetátot elsőként nyertük ki ebből az Ajuga fajból. | We studied the efficacy of whole plant grist (Plodia interpunctella), crude and fractionated methanolic extracts (Acyrthosiphon pisum, Dysdercus cingulatus, Aedes aegypti, Daphnia magna) as well as pure ecdysteroids from different Ajuga spp. In the Plodia-test the strongest effects were found at 8% concentration of A. reptans grist, which reduced the pupal weight, doubled the postembryonic developmental time, and caused 77% mortality until emergence of adults. In the Aedes-test the crude as well as the 100% methanolic fraction from A. reptans showed high efficacy (80% mortality at 0.1% concentration). In the case of sucking insect species (A. pisum, D. cingulatus) the 100% methanolic fraction of A. chamaepitys and the 60% methanolic fraction of A. bracteosa were highly effective on A. pisum (100% mortality at 0.1% concentration) Polipodine B and 20-hydroxyecdysone were the most effective pure phytoecdysteroids on aphids (LC50 = 0.21 ppm and 1.07 ppm). We have identified 10 different ecdysteroids from the Ajuga reptans var. reptans (20-hydroxyecdysone, 20-hydroxyecdysone acetate, cyasterone, cyasterone 3 acetate, 29-nor-cyasterone, ajugasterone B', ajugalactone, sengosterone, 23-hydroxi-kapitasterone, 24-ethyl-24,26-dihydroxi-taxisterol 26-metilat). Among these 23-hydroxi-capitasterone and 24-ethyl-24,26-dihydroxi-taxisterol 26-metilat are new phytoecdysteroids while, 20-hydroxyecdysone acetate and cyasterone 3 acetate were firstly isolated from A. reptans

Apró közlemények / Short communications

1. Közönséges kígyónyelv (Ophioglossum vulgatum) meglepő új előfordulása a Tiszafüred–Kunhegyesi síkon / Occurrence of Ophioglossum vulgatum in a dry loess grassland in the Tiszafüred–Kunhegyes plain (Great Hungarian Plain) 2. Útépítési nyersanyaggal behurcolt dolomitsziklagyep-fajok tömeges megjelenése Kecskeméten / Dolomite rocky grassland species introduced by raw materials of a road construction (Kecskemét, Great Hungarian Plain) 3. Geranium divaricatum a Hevesi-síkon, Füzesabony mellett / Geranium divaricatum on the Hevesi-sík, next to Füzesabony (Great Hungarian Plain) 4. A pókbangó (Ophrys sphegodes) új előfordulása a vasi flórajárás területén / Ophrys sphegodes in the Castriferreicum (W Hungary) 5. A Cephalanthera longifolia rosea első kimutatása Magyarországon / First occurrence of Cephalanthera longifolia var. rosea in Hungary 6. Spiraea crenata a Keleti-Bakonyban / Spiraea crenata in the Eastern Bakony Mts (Transdanubian Range, Hungary

Novel results of two-dimensional thin-layer chromatography

Various types of two-dimensional thin-layer chromatography are presented. Even using appropriately selective systems, multicomponent mixtures can result in spots around the main diagonal, but they can be spread all over the TLC plate simply by improvements in the mobile phase composition. The use of cyano-silica offers the change of normal-phase to reversed-phase separations in the first and second dimensional developments. Elution type developments can be combined with displacement chromatography; thereby, a unique possibility of different separation mechanisms can be utilized

Dynamic on-column eluent modification: A novel strategy for peak resolution enhancement. Application to the preparative separation of ecdysteroid isomers

A novel LC method was applied to enhance the peak resolution of two ecdysteroids: 20-hydroxyecdysone and its 3-epimer. An isocratic solvent system of methanol-water (6:4, v/v) was used on a C18 column, and 100 mu L of water was injected during the development in such a manner that the eluted solvent peak appeared exactly between the two overlapping peaks. This resulted in the increased retardation of the later-eluted peak, and in a good separation of the two compounds within 4.5 min

Phytoecdysteroids and vitamin D analogues - Similarities in structure and mode of action

Phytoecdysteroids are plant steroids with identical or analogue structures to the molting hormone in arthropods. The ecdysteroids exert several beneficial effects on mammals, from which the most cited and deeply examined one is the increase of muscle size and strength. This shows similarities with the mode of action of the androgenic steroids but the ecdysteroids do not bind to the cytoplasmic/nuclear receptor of the mammalian steroids. These findings led to the hypothesis that ecdysteroids possibly bind to membrane bound receptors and they are likely to influence signal transduction pathways. Probably because of their closely related chemical structures, ecdysteroids exert some similar effects in vertebrates to those of the hormone 1 alpha,25-dihydroxyvitamin D3 (1,25D) which is produced in the kidney from 25-hydroxyvitamin D3, after being converted in the liver from Vitamin D3. 1,25D generates biological responses via both genomic and rapid, nongenomic mechanisms. Structure-activity relationship studies with different Vitamin D analogues could open the possibility to show that the two ways of action (genomic and nongenomic) can be influenced separately. The connection between the Vitamin D status and muscle function is already well-described in clinical studies, and several efforts have been made to evaluate the effect of Vitamin D deficiency or supplementation on muscle morphological changes and the underlying molecular mechanisms. This paper aims to summarize the main structural commonalities between the ecdysteroids, 1,25D and other Vitamin D analogues. The similarities in their effects and pathways that might be involved in the mechanism of action of these compounds will also be discussed