In the course of our research on the oligoglycosidic constituents of Turkish Astragalus species, we have isolated a number of cycloartane-type triterpene glycosides. The current study examines the immunostimulatory effects of nineteen of these cycloartane-type compounds using a transcription-based bioassay for Nuclear Factor kappa B (NF-kappaB) activation in a human macrophage/monocyte cell line, THP-1. All compounds were inactive at 100 microg/ml except astragaloside I which increased NF-kappaB directed luciferase expression to levels about 65% as compared with maximal stimulation by E. coli lipopolysaccharide (LPS) at 10 microg/ml. None of the compounds were active at low dosage levels (0.1 microg/ml) in combination with 50 ng/ml LPS. Astragaloside I also increased mRNA expression of the inflammatory cytokines interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) as measured using reverse transcriptase-polymerase chain reaction (RT)-PCR. Based on these results it is clear that certain structural features are required for immunostimulation of cycloartane-type triterpene glycosides.

BACKGROUND: The most common commercially available pine bark extract is Pycnogenol  , a standardised extract of Pinus maritima, which has been reported to have cardiovascular benefits and enhance microcirculation. The present study was conducted to determine the chemical composition of four pine bark extracts, assess their biological activities and to compare the results with Pycnogenol  .

SummaryThe main triterpene glycosides of Cimicifuga racemosa were separated by reversed phase HPLC, using a 018 column, Evaporative Light Scattering (ELS) detection and a gradient system consisting of water, acetonitrile and reagent alcohol. Within 35 min three main glycosides could be separated and quantified in the methanohc root extract, with detection limits of 10.5, 15.6 and 31.6 I~g 9 mL 1 respectively. The method was successfully used to analyze different Cimicifuga racemosa market products, as well as to distinguish bef,,veen other Cimicifuga samples from China.

From the aerial parts of the plant Verbascum salviifolium, two new iridoid glucosides, 6-O-β -Dglucopyranosylcatalpol (1) and 6-O-(6 -O-trans-p-hydroxycinnamoyl)-β -D-glucopyranosylaucubin (2) along with five known iridoid glycosides,were isolated. The structures of the new compounds were established on the basis of spectroscopic evidence.