Quantification of cynaropicrin in artichoke leaf extracts by ¹H NMR spectroscopy.

The quantification of cynaropicrin in artichoke leaf extracts (ALE) by means of quantitative ¹H NMR was performed. The method relies on solid phase extraction for sample preparation and spectra acquisition in DMSO- D₆ containing anthracene as the internal standard. The obtained ¹H NMR spectra revealed excellent signal purity for H-13(b) of cynaropicrin, which was thus chosen for quantification.

Metabolic fingerprinting of Leontopodium species (Asteraceae) by means of ¹H NMR and HPLC-ESI-MS.

The genus Leontopodium, mainly distributed in Central and Eastern Asia, consists of ca. 34-58 different species. The European Leontopodium alpinum, commonly known as Edelweiss, has a long tradition in folk medicine.

Identification and quantification of major steviol glycosides in Stevia rebaudiana purified extracts by 1H NMR spectroscopy.

The use of (1)H NMR spectroscopy for the characterization of Stevia rebaudiana extracts is presented. The developed method allows qualitative and quantitative determination of the major steviol glycosides in purified extracts and fractions obtained from various stages of the purification process. Moreover, it proved to be a powerful tool to differentiate between glycosides which are naturally occurring in the stevia plant and artifacts formed in the course of the manufacturing process.

Analysis of iridoids, secoiridoids and xanthones in Centaurium erythraea, Frasera caroliniensis and Gentiana lutea using LC-MS and RP-HPLC.

This study presents a new and validated HPLC method for the simultaneous determination of bioactive compounds in Centaurium erythraea, Frasera caroliniensis and Gentiana lutea. The iridoid loganic acid, four secoiridoids and 29 xanthones were separated on a RP-18 column, using aqueous o-phosphoric acid (0.085%, v/v) and acetonitrile as mobile phase.

Identification and pharmacological characterization of the anti-inflammatory principal of the leaves of dwarf elder (Sambucus ebulus L.).

Aim Of The Study: The performed investigations aimed on the identification of the anti-inflammatory principal of extracts of leaves of Sambucus ebulus L. (dwarf elder) in order to rationalize the traditional use of this plant for the treatment of chronically inflammatory diseases.

Materials And Methods: Dwarf elder leaf extract was subjected to activity guided fractionation using inhibition of TNFα induced expression of vascular cell adhesion molecule 1 (VCAM-1) on the surface of human umbilical vein endothelial cells (HUVECs) as monitoring tool (positive control: parthenolide 10μM, VCAM-1 expression (% of control): 5.

Iridoid glycosides from the leaves of Sambucus ebulus.

Six new iridoid glycosides (1-6) of the "Valeriana type" were isolated from leaves of Sambucus ebulus. The structures were elucidated by 1D- and 2D-NMR spectroscopy, mass spectrometry, and chemical degradation methods as 10-O-acetylpatrinoside-aglycone-11-O-[4''-O-acetyl-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-ribohexo-3-ulopyranoside] (1), 7-O-acetylpatrinoside-aglycone-11-O-[4''-O-acetyl-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-ribohexo-3-ulopyranoside] (2), 10-O-acetylpatrinoside-aglycone-11-O-[alpha-L-rhamnopyranosyl-(1-->2)-beta-D-ribohexo-3-ulopyranoside] (3), patrinoside-aglycone-11-O-[4''-O-acetyl-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-ribohexo-3-ulopyranoside] (4), 10-O-acetylpatrinoside-aglycone-11-O-[4''-O-acetyl-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside] (5), and patrinoside-aglycone-11-O-2'-deoxy-beta-D-glucopyranoside (6). Compounds 1-4 represent the first examples of acylated iridoid diglycosides bearing the uncommon D-ribohexo-3-ulopyranosyl sugar moiety.