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An HPLC method was developed for simultaneous determination of one phenylpropanoid glycoside, verbascoside (1), and nine lignans, including lantibeside (2), phillyrin (3), lantibeside B (4), lantibeside C (5), tibeticoside A (6), styraxjaponoside C (7), sylvatesmin (8), (+)-piperitol (9), and horsfieldin (10), from the Tibetan medicinal plant Lancea tibetica Hook. F. et Thoms. The analysis was performed within 45 min. The extraction method was optimized with different solvent systems. The HPLC method was validated for linearity, repeatability, accuracy, limits of detection, and limits of quantification. The limits of detection and limits of quantification of 10 analytes were found to be less than 0.1 and 0.5 µg/mL, respectively. The RSD for intra- and inter-day analyses was less than 4.2 %, and the recovery efficiency was 90-105 %. The method was used to analyze different populations of L. tibetica collected in China. HPLC profiles showed that the concentrations of analytes were different in samples collected from different areas of China. Verbascoside was the dominant component in three out of five plant samples; compounds 2, 3, 6, and 8 accounted for over 62 % yields in total lignan contents. The method is useful for identification, quality assurance, and quality control of L. tibetica and its related products., (© Georg Thieme Verlag KG Stuttgart · New York.)

A histologically validated murine model for the ovine intoxication by Stemodia kingii was used as a bioassay to guide the isolation of several groups of toxins from Stemodia kingiL Two of the toxins from one group were purified sufficiently to allow structural analysis and a determination of their median lethal doses (LD50) for oral administration to mice. A combination of acid hydrolysis, elemental analysis, HPLC-MS, 1D-NMR (1H, 13C) and 2D-NMR (1H-1H COSY, 13C-1H HSQC and HMBC, and gNOESY) was used to define stemodiosides B3 and B4 as cucurbitacin steroidal glucosides. Thus stemodioside B3 is (24Z)-3 alpha-(beta-glucopyranosyloxy)-2 beta,20,27-trihydroxy- 19-(10 -9 beta)-abeo-10alpha-lanost-5,24-diene- 11-one and stemodioside B4 is (23E)-3 alpha-(beta-glucopyranosyloxy)-20,20,22,27-tetrahydroxy- 19-( 10-9 beta)-abeo- 10 alpha-lanost-5,23-diene- 11-one. The approximate oral LD50s for stemodiosides B3 and B4 in mice were estimated to be 99 and 42 mg/kg body weight, respectively.

From the hydromethanolic extract of the aerial parts of Globularia alypum grown in Morocco, a new chlorinated iridoid glucoside, globularioside has been isolated beside 5 known iridoid glycosides, globularin, globularicisin, globularidin, globularinin and globularimin. This is the first report of a chlorinated iridoid in G. alypum and in the Globulareaceae. Unlike all other known 7-chlorinated iridoid glucosides where the chlorine atom exhibits an alpha configuration, globularioside incorporate the chlorine atom as a 7beta substituent. The structures of the isolated compounds were established on the basis of ESI-MS, MS-MS, 1D and 2D NMR spectral analysis.

Aim: To investigate the chemical constituents from Picria fel-terrae Lour., Methods: Column chromatography techniques were used to isolate the chemical constituents, physico-chemical constants and spectroscopic analysis were employed for structural elucidation. Results Two triterpenoids named picfeltarraenone I (1) and picfeltarraenin XI (2) were isolated, and their structures were established to be 3,11,22-trioxo-16alpha-hydroxy-(20S,24)-epoxy-cucurbit-5,23-diene (1) and 3,11,22-trioxo-16alpha-hydroxy-(20S,24)-epoxy-cucurbit-5, 23-diene-2beta-O-beta-D-glucopyranoside (2), respectively., Conclusion: Compound 2 is a new compound, the 13CNMR data of compound 1 is reported for the first

Two unique 2-(3,4-dihydroxyphenyl)ethyl glycosides, namely, dopaol beta-D-2-ketoglucopyranoside and dopaol beta-D-2,3-diketoglucopyranoside, were isolated from Chelone obliqua together with the iridoid glucoside catalpol, dopaol beta-D-glucopyranoside, descaffeoylverbascoside, and verbascoside. Glycosides with a diketosugar have not so far been isolated from natural sources.

LC-UV-MS analysis of the methanol extract of Jamesbrittenia fodina O. M. Hilliard (Scrophulariaceae) revealed the presence of cinnamic ester derivatives. Two isomeric pairs of these constituents were detected, but could not be isolated. In order to identify these unstable compounds, LC-1H-NMR spectra were obtained for each individual isomer and standard NMR measurements were performed in-mixture. The spectra clearly demonstrated that the fractions consisted of mixtures of cis and trans cinnamoyl catalpol glycoside esters.

A new phenylethanoid glycoside, persicoside (1) and three known phenylethanoid glycosides, acteoside (2), isoacteoside (3) and lavandulifolioside (4) were isolated from the aerial parts of Veronica persica. On the basis of spectral analyses, the structure of the new compound was elucidated to be 3,4-dihydroxy-beta-phenylethoxy-O-[beta-D-glucopyranosyl-(1-->2)]-[beta-D-glucopyranosyl-(1-->3)]-4-O-caffeoyl-beta-D-glucopyranoside. Persicoside (1) and acteoside (2) exhibited radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical. Beside phenylethanoid glycosides, a hexitol, dulcitol (5) and seven known iridoid glucosides, aucubin (6), veronicoside (7), amphicoside (8), 6-O-veratroyl-catalpol (9), catalposide (10), verproside (11) and verminoside (12) were isolated.

A protocol for de novo regeneration and rapid micropropagation of Scrophularia yoshimurae (Scrophulariaceae) has been developed. Multiple shoot development was achieved by culturing the shoot-tip, leaf-base, stem-node and stem-internode explants on Murashige and Skoog (MS) medium supplemented with 4.44 microM N6-benzyladenine (BA) and 1.07 microM alpha-naphthaleneacetic acid (NAA). Stem-node and shoot-tip explants showed the highest response (100%) followed by stem-internode (74.4%) and leaf-base (7.7%) explants. The shoots were multiplied by subculturing on the same medium used for shoot induction. Shoots were rooted on growth regulator-free MS basal medium and the plantlets were transplanted to soil and acclimatized in the growth chamber. The content of harpagoside, a quantitatively predominant iridoid glycoside, in different plant material was determined by high performance liquid chromatography (HPLC). The analysis revealed that the content of harpagoside in the aerial and underground parts of S. yoshimurae was significantly higher than the marketed crude drug (underground parts of Scrophularia ningpoensis).

A fast and easy method was sought for determination of the iridoid glycosides catalpol, ketologanin, verbenalin, loganin, 8-epi-loganic acid, geniposidic acid and 10-cinnamoyl catalpol in plant samples. The method involved micellar electrokinetic capillary chromatography (MEKC) coupled on-line to mass spectrometry. The partial filling technique and electrospray ionization were used. Seven iridoid glycosides could be separated with use of MEKC under basic conditions. However, 8-epi-loganic acid and geniposidic acid could not be detected simultaneously with the five neutral iridoid glycosides by mass spectrometry. Therefore, only the neutral iridoid glycosides were screened from plant samples. Catalpol, verbenalin, loganin and possibly 10-cinnamoyl catalpol were found in an examination of seven plant species in the genera Plantago, Veronica, Melampyrum, Succisa, and Valeriana. Aucubin, which was not included in the sample mixture used in method development because of overlapping with catalpol in MEKC, was also detected. The limits of detection for the iridoid glycosides, both at the UV and at the mass spectrometer, are given.

Aim: To investigate the antioxidative activity of the constituents of the roots of Scrophularia ningpoensis (Chinese name: Xuanshen)., Methods: The main compounds from the roots of Scrophularia ningpoensis were isolated and identified by chromatography and FABMS, NMR etc. Using the techniques of pulse radiolysis, the electron transfers from iridoid glycosides (IG) or phenylpropanoid glycosides (PG) to oxidized OH radical adducts of 2'-deoxyadenosine-5'-monophosphate acid (dAMP) or 2'-deoxyguanosine-5'-monophosphate acid (dGMP) were observed., Results: Two IG: harpagoside and harpagide, two PG: angoroside C and acteoside were obtained as the main hydrophilic constituents of the plant. At 0.1 mmol/L concentration, angoroside C and acteoside were able to repair the oxidized OH adducts dAMP and dGMP significantly. However, harpagoside and harpagide had no such effect. The electron transfer rate constants of angoroside C with dAMP and dGMP were 4.2 x 10(8) and 10.3 x 10(8) L.mol-1.s-1; the electron transfer rate constants of acteoside with dAMP and dGMP were 5.3 x 10(8) and 20.2 x 10(8) L.mol-1.s-1., Conclusion: PG from Scrophularia ningpoensis have a potent antioxidative activity for reducing of the oxidized OH adducts of dAMP and dGMP.