Secondary metabolites from Asperula lutea subsp. rigidula.

From the aerial parts of Asperula lutea subsp. rigidula (Halacsy) Ehrend., an endemic plant of south-eastern Greece, nine known compounds, beta-sitosterol, geniposidic acid, deacetyl-asperuloside, scandoside, chlorogenic acid, quercetin, hyperin, isoquercitrin and rutin, were isolated.

Chemical composition of the essential oil of Achillea umbellata growing in Greece.

The essential oil of the aerial parts of the endemic Achillea umbellata (Compositae) was obtained by hydrodistillation and analysed by gas chromatography (GC) and gas chromatography coupled to mass spectrometry (GC-MS). Sixty-six constituents were identified. The major constituents of the oil were beta-thujone (62.

Volatile metabolites from Salvia fruticosa as antifungal agents in soilborne pathogens.

The volatile metabolites of Salvia fruticosa plants, growing wild in 15 localities scattered across Greece, were analyzed by means of GC and GC-MS. The essential oil content ranged from 0.69 to 4.

Acetylene sesquiterpenoid esters from the green alga Caulerpa prolifera.

Sixteen secondary metabolites of the green alga Caulerpa prolifera have been isolated, and their chemical structures elucidated by analysis of their spectroscopic data. Two groups of metabolites have been established, with either a 1,2-dihydro- (2a-2i) or a 1,2,3,3'-tetrahydro-2,3-didehydro (3a-3f) caulerpenyne carbon backbone. The terminal vinyl acetoxy group of caulerpenyne was substituted by various fatty acid residues.

Antioxidant activity of polyphenols from Hypericum triquetrifolium Turra.

From the aerial parts of Hypericum triquetrifolium Turra (Guttiferae) 3-8"-biapigenin, quercetin, rutin and chlorogenic acid were isolated. Their structures were elucidated by spectral techniques. Furthermore, the phenolic compounds were tested for antioxidant activity, using an in vitro method based on sodium arachidonoate, bleomycin and thiobarbituric acid with alpha-tocopherol as the reference solution.