Liquid chromatography/electrospray tandem mass spectrometry of terpenoid lactones in Ginkgo biloba.

Ginkgo biloba (ginkgo) is one of most frequently used botanical dietary supplements. The bioactive constituents include the terpenoid lactones consisting of bilobalide and the ginkgolides A, B, C and J. A new assay based on high-performance liquid chromatography/electrospray tandem mass spectrometry (LC/MS/MS) was developed for the measurement of the terpenoid lactones in ginkgo products such as leaf powder and extracts.

Differential enantioselectivity and product-dependent activation and inhibition in metabolism of verapamil by human CYP3As.

In vitro studies of enantioselective metabolism of R-(+)- and S-(-)verapamil (VER) were conducted using human cDNA-expressed CYP3A isoforms, CYP3A4, CYP3A5, and CYP3A7. N-dealkylated products nor-VER [2,8-bis-(3,4-dimethoxyphenyl)-2-isopropyl-6-azaoctanitrile] and D617 [2-(3,4-dimethoxyphenyl)-5-methylamino-2-isopropylvaleronitrile] were the major metabolites for all CYP3A isoforms regardless of enantiomer. Enantioselectivity of CYP3A4 and CYP3A7 was most similar among the three isoforms.

Identification of caffeic acid derivatives in Actea racemosa (Cimicifuga racemosa, black cohosh) by liquid chromatography/tandem mass spectrometry.

Caffeic acid derivatives occurring in black cohosh [Cimicifuga racemosa (L.) Nutt., Actaea racemosa (Ranunculaceae)], some of which may have pharmacological activity, were analyzed using high-performance liquid chromatography (HPLC) electrospray ionization tandem mass spectrometry (ESI-MS/MS) with the aim of developing a methodology for their rapid identification in a complex plant matrix.

p-Hydroxybenzoic acid alkyl esters in Andrographis paniculata herbs, commercial extracts, and formulated products.

Analysis of two commercial extracts of Andrographis paniculata using high-performance liquid chromatography (HPLC) with photodiode array absorbance detection showed the presence of several unexpected compounds, which were isolated and identified as methyl, ethyl, and propyl esters of p-hydroxybenzoic acid by using high-resolution mass spectrometry and nuclear magnetic resonance. Quantitative analysis using HPLC revealed the presence of 0.22% p-hydroxybenzoic acid methyl ester (methlyparaben) in one commercial extract, and both 0.

Evaluation of commercial ginkgo and echinacea dietary supplements for colchicine using liquid chromatography-tandem mass spectrometry.

In response to concerns that commercial dietary supplements containing Ginkgo biloba (ginkgo) and Echinacea purpurea, Echinacea angustifolia, or Echinacea pallida (echinacea) might be contaminated with colchicine, a highly selective and sensitive assay was developed for colchicine that is based on high-performance liquid chromatography-tandem mass spectrometry (LC-MS-MS). The method utilizes reversed-phase HPLC separation of compounds in a methanolic extract of the dietary supplement or botanical sample followed by positive ion electrospray ionization with collision-induced dissociation and multiple reaction monitoring of three characteristic fragmentation pathways of the protonated molecule of colchicine, m/z 400 --> 358, 400 --> 326, and 400 --> 310. The minimal detectable concentration of colchicine using this assay was 10 pg on-column, which is equivalent to 20 ppb colchicine in a 0.

Simultaneous determination of terpene lactones and flavonoid aglycones in Ginkgo biloba by high-performance liquid chromatography with evaporative light scattering detection.

A gradient high performance liquid chromatographic method with evaporative light scattering detection (ELSD) for the simultaneous determination of ginkgolide A, ginkgolide B, ginkgolide C, ginkgolide J, bilobalide, quercetin, kaempferol and isorhamnetin in Ginkgo biloba is described. Samples are analyzed by means of a reverse-phase column (Supelco Discovery C-18) using methanol (containing 0.05% TFA) and water (containing 5% methanol and 0.

Isolation, structure elucidation, and absolute configuration of 26-deoxyactein from Cimicifuga racemosa and clarification of nomenclature associated with 27-deoxyactein.

A new triterpene glycoside, 26-deoxyactein (1), along with two known compounds, 23-epi-26-deoxyactein (2), previously designated as "27-deoxyactein", and actein (3), were isolated from the roots/rhizomes of Cimicifuga racemosa. The structures and absolute stereochemistry of 1 and 2 were established by spectroscopic methods (FABMS, (1)H and (13)C NMR) and single-crystal X-ray data analysis.

A validated high performance liquid chromatographic method for the analysis of Goldenseal.

Goldenseal (Hydrastis canadensis L.) has emerged as one of the top ten herbal supplements on the worldwide market. A rapid, simple and validated high performance liquid chromatographic method, with photodiode array detection, has been developed for the analysis of commercial Goldenseal products.