Ultraperformance Liquid Chromatography Tandem Mass Spectrometry Determination of Cyanogenic Glucosides in <i>Trifolium</i> Species

Cyanogenic glucosides were analyzed by ultra-high-performance liquid chromatography combined with mass spectrometry in 88 <i>Trifolium</i> species grown at the same site. On the basis of the occurrence of cyanogenic glucosides and the linamarin/lotaustralin ratio species could be grouped into five clusters. Cluster C1 included 37 species, which did not contain cyanogens. Cluster C2 (22 species) included plants containing only lotaustralin. In clusters C3 (14 species), C4 (13 species), and C5 (2 species) both linamarin and lotaustralin were present but at different ratios. In C3 and C4 the linamarin/lotaustralin ratio was below 1, whereas in cluster C5 the ratio was much higher. Generally, the total content of cyanogens was below 500 μg/g dry matter. Only in <i>Trifolium repens</i> var. <i>biasoletti</i> and <i>Trifolium montanum</i> extremely high cyanogen concentrations were observed. There was no general rule of occurrence of cyanogens. Samples of the same species from different countries accumulated cyanogens or could be free of these compounds

Isolation, Chemical and Free Radical Scavenging Characterization of Phenolics from Trifolium scabrum L. Aerial Parts

For the first time Trifolium scabrum L. was researched for its phenolic profile. Sixteen phenolics (isoflavones and flavonoids) were isolated and identified in the aerial parts of <i>T. scabrum</i> L. Their structures were established by electrospray ionization–mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR) techniques. Quantitative analysis of individual phenolics performed by means of ultraperformance liquid chromatography–mass spectrometry (UPLC-MS) was based on calibration curves obtained for previously isolated standard compounds. Additionally, the free radical scavenging potential of these substances was assessed by means of a simple benchtop thin-layer chromatography–2,2-diphenyl-1-picrylhydrazyl radical (TLC-DPPH^•) bioassay. Thus, <i>T. scabrum</i> L. can be regarded as a potential source of estrogenic and antioxidant compounds, both of significance in the pharmaceutical as well as the food industry. The results show that <i>T. scabrum</i> L. can be considered as a natural and very good commercial source of phenolic compounds (mainly isoflavones)

Unusual Fernane and Gammacerane Glycosides from the Aerial Parts of <i>Spergula fallax</i>

The aerial parts of <i>Spergula fallax</i> afforded four glycosides (<b>1</b>–<b>4</b>) based on two new triterpene aglycones (<b>1a</b> and <b>2a</b>), along with the known hopane glycoside succulentoside A. Compound <b>1</b> was identified as belonging to the fernane class, unusual migrated hopane triterpenoids, mainly isolated from ferns and only rarely from higher plants. Compounds <b>2</b>–<b>4</b> were assigned as gammacerane glycosides, having as aglycone a hydroxylated derivative of tetrahymanol. The structures of the isolated compounds <b>1</b>–<b>4</b> and their aglycones <b>1a</b> and <b>2a</b> obtained by acid hydrolysis were elucidated by spectroscopic data interpretation. The growth inhibitory activity of the isolated compounds and their aglycones was evaluated against the HeLa and DLD-1 cancer cell lines