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The gamma-amino butyric acid (GABA) type A (GABAA) receptor represents a crucial target for clinical agents in the treatment of anxiety and insomnia. Using the two-microelectrode voltage clamp technique on recombinant α1β2γ2S GABAA receptors, effusol (1) and dehydroeffusol (2) were isolated in a bioactivity-guided approach from the pith of Juncus effusus L. Both compounds concentration-dependently enhanced GABA induced chloride currents (IGABA) by a maximum 188 ± 20 (1) and 239 ± 18% (2), independent of the benzodiazepine (BZ) binding site. This activity on the GABAA receptor may explain the traditional use of J. effusus as a sedative and anxiolytic agent in Chinese medicine. [ABSTRACT FROM AUTHOR]

In some medicinal plants a specific plant-fungus association, known as arbuscular mycorrhizal (AM) symbiosis, increases the levels of secondary plant metabolites and/or plant growth. In this study, the effects of three different AMtreatments on biomass and sesquiterpenic acid concentrations in two in vitro propagated genotypes of valerian (Valeriana officinalis L., Valerianaceae) were investigated. Valerenic, acetoxyvalerenic and hydroxyvalerenic acid levels were analyzed in the rhizome and in two root fractions. Two of the AMtreatments significantly increased the levels of sesquiterpenic acids in the underground parts of valerian. These treatments, however, influenced the biomass of rhizomes and roots negatively. Therefore this observed increase was not accompanied by an increase in yield of sesquiterpenic acids per plant. Furthermore, one of the two genotypes had remarkably high hydroxyvalerenic acid contents and can be regarded as a hydroxyvalerenic acid chemotype. [ABSTRACT FROM AUTHOR]

For the first time the composition of the bufadienolide complex in URGINEA HESPERIA Webb & Berth. has been investigated. From an extract of lyophilized plants, thirteen bufadienolides were isolated. By means of FAB-MS, 1H-NMR, and 13C-NMR studies the compounds were structurally elucidated as scillarenin, scilliphaeosidin, scillarenin-3- O-?- L-rhamnoside, scilliphaeosidin-3- O-?- L-rhamnoside, gamabufotalin-3- O-?- L-rhamnoside, 11?-hydroxyscilliglaucosidin-3- O-?- L-rhamnoside, scillarenin-3- O-?- L-2',3'-diacetylrhamnosido-4'-?- D-glucoside, scillarenin-3- O-?- L-rhamnosido-4'-?- D-glucosido-3?-?- D-glucoside, scillarenin-3- O-?- L-rhamnosido-4'-?- D-glucosido-4?-?- D-glucoside, scillarenin-3- O-?- L-2',3'-diacetylrhamnosido-4'-?- D-glucosido-3?-?- D-glucoside, scillarenin-3- O-?- L-2',3'-diacetylrhamnosido-4'-?- D-glucosido-4?-?- D-glucoside, scilliphaeosidin-3- O-?- L-rhamnosido-4'-?- D-glucosido-3?-?- D-glucoside, and scilliphaeosidin-3- O-?- L-rhamnosido-4'-?- D-glucosido-4?-?- D-glucoside.

From bulbs of URGINEA PANCRATION (Steinh.) G. de Philippe (Hyacinthaceae) 5 bufadienolides were isolated by a combination of column and droplet counter-current chromatography; their structures were elucidated mainly by FAB-MS and 1H- and 13C-NMR spectroscopy. Besides the already known scilliglaucoside ( 1), scillirubroside ( 2), and scilliroside ( 3), two new bufadienolides were identified: 5?-4,5-dihydroscillirosidin- 3?- O-?- L-thevetosido-4'-?- D-glucopyranoside and arenobufagin-3?- O- L-rhamnopyranosido-4'-?- D-glucopyranoside.