3 research outputs found
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<sup>•</sup>) 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