Biological activities and 3D QSAR studies of a series of Delisea pulchra (cf. fimbriata) derived natural products.

Twenty-five natural products, mainly halogenated furanones, isolated from the temperate red algae Delisea pulchra were investigated for their cytotoxic, antimicrobial, and antiplasmodial effects, their inhibition of the activity of the enzymes HIV-1-RT (HIV-1-reverse transcriptase), PKC (protein kinase C), and TK (tyrosine kinase), and their inhibition of the biosynthesis of IL-1 (interleukin-1). All were found to mediate a positive response in one or more of these test systems. In particular, compounds 9, 11, 12, 14, 16, 17, 19, and 20 demonstrated cytotoxic activity in all of the assays they were tested in; compounds 11, 12, 17, 19, and 20 were also active in the majority of the anti-infective screens.

Evaluation of the efficiency of three different solvent systems to extract triterpene saponins from roots of Panax quinquefolius using high-performance liquid chromatography.

Despite the wide availability of liquid herbal extracts using mixtures of alcohol, glycerin, and water, or glycerin and water as solvents, no data on the chemical composition of such extracts is readily available. In this study, the amount and the stability of the major saponins in Panax quinquefolius root extracts, made either with 50% (v/v) aqueous ethanol, a mixture (v/v/v) of 20% ethanol, 40% glycerin, and 40% water, or with 65% (v/v) aqueous glycerin, were evaluated by HPLC-UV analysis. The amount of total saponins was highest in the 50% aqueous ethanol extract (61.

Analysis of Scutellaria lateriflora and its adulterants Teucrium canadense and Teucrium chamaedrys by LC-UV/MS, TLC, and digital photomicroscopy.

Methods using liquid chromatography with UV detection (LC-UV), thin-layer chromatography (TLC), and digital photomicroscopy were developed to distinguish between the different species of Scutellaria lateriflora L. and its adulterants Teucrium canadense L. and T.

Inhibition of [3H]-LSD binding to 5-HT7 receptors by flavonoids from Scutellaria lateriflora.

The hot water and 70% ethanol extracts of dried mad-dog skullcap (Scutellaria lateriflora) both bound to the 5-HT(7) receptor, with 87.2 +/- 6.2% and 56.

Stabilization of caffeic acid derivatives in Echinacea purpurea L. glycerin extract.

Recent work has shown that enzymatic degradation and oxidation of cichoric acid and other caffeic derivatives occurs in Echinacea preparations. However, very little is known as to the means of stabilizing these phytopreparations. To stabilize the glycerin extract of Echinacea purpurea, we have evaluated the effects of 3 natural antioxidants (citric acid, malic acid, and hibiscus extract) on the stability of the major caffeic acid derivatives (caftaric acid, caffeic acid, cichoric acid, and 2-O-feruloyl-tartaric acid).