L.-Z. Xu

Development of an in-line HPLC fingerprint ion-trap mass spectrometric method for identification and quality control of Radix Scrophulariae

Chromatographic fingerprinting has been widely accepted as a crucial method for qualitative and quantitative analyses of bioactives within traditional Chinese medicine. A fingerprint provides detailed information, specific for any given herb, thus facilitating the quality control measures of a given traditional Chinese medicine. In this article, quality assessment of Radix Scrophulariae was achieved by using high performance liquid chromatography combining diode-array detection and electrospray ionization mass spectrometry (HPLC-DAD-ESI/MS). Eight batches of sample obtained from different origins in China were used to establish the fingerprint and quantitative analyses. By comparing the retention times, UV and MS spectral data with reference standards, four characteristic peaks in the chromatograms were confirmed as corresponding to acetoside, angoroside C, cinnamic acid, and harpagoside. In addition, other two characteristic peaks were tentatively identified, following the literature interpretation of HPLC-ESI-MS and LC-MS/MS (affording structural information) to be sibirioside A and scrophuloside B(4), respectively. The results indicated that the newly developed HPLC-DAD-MS fingerprint method would be suitable for quality control of Radix Scrophulariae.

Diarylheptanoids from Alpinia officinarum

A new diarylheptanoid, along with five known diarylheptanoids, was isolated from the rhizomes of Alpinia officinarum (Zingiberaceae). The structure of the new compound was determined to be trans,trans-1(3′-methoxy-4′-hydroxyphenyl)-7-phenyl-5-ol-4,6-dien-3-heptanone on the basis of spectral and chemical evidence.

Simultaneous Determination of Eight Anthraquinones in Semen Cassiae by HPLC-DAD

INTRODUCTION Semen Cassiae (SC), a traditional Chinese herbal medicine for the treatment of various diseases, is known to contain active anthraquinone ingredients. However, since the content of some anthraquinones is too low, previous analytical methods only allow the quantitation of a few anthraquinones or a hydrolysis step has to be included in the sample preparation. A rapid and accurate method to examine the content of as many anthraquinones as possible in SC would be desirable. OBJECTIVE To develop a rapid, sensitive and accurate high-performance liquid chromatography-diode array detection (HPLC- DAD) method to simultaneously quantify eight major anthraquinones (obtusifolin-2-glucoside, aurantio-obtusin, aloe- emodin, rhein, obtusifolin, emodin, chrysophanol and physcion) in SC. METHODOLOGY The separation of anthraquinones was achieved on a C₁₈-column with a gradient elution using acetonitrile and 0.1% phosphoric acid. The detection wavelength was 278 nm and the analysis finished within 25 min. RESULTS The limits of detection of these compounds ranged from 0.07 to 0.15 µg/mL while the limits of quantitation ranged from 0.24 to 0.51 µg/mL. All calibration curves showed good linearities (r²  > 0.999) within the test ranges. This validated method was successfully used to analyse 22 batches of SC samples collected from various geographical locations. CONCLUSION The method was validated to be simple, rapid, accurate and reliable to simultaneously determine eight major anthraquinones in SC. Meanwhile, a more specific anthraquinone, obtusifolin, was proposed to serve as a marker for SC, replacing chrysophanol.

Anti-inflammatory activities and mechanisms of action of the petroleum ether fraction of Rosa multiflora Thunb. hips.

ETHNOPHARMACOLOGICAL RELEVANCE The hip of Rosa multiflora Thunb. has been traditionally used as a dietary supplement and a herbal remedy for the treatment of various diseases including cold, flu, inflammation, osteoarthritis, rheumatoid arthritis and chronic pain in China. AIMS OF THE STUDY To explore the anti-inflammatory ingredient of the hip of R. multiflora Thunb. and its mechanism of action. MATERIALS AND METHODS The ethanol extract of the hip of R. multiflora Thunb. was fractioned with petroleum ether, ethyl acetate and water, and each fraction was screened for anti-inflammatory activity in xylene-induced mouse ear edema model. Three more models, acetic acid-induced mouse vascular permeation, cotton pellet-induced rat granuloma, and carrageenan-induced rat hind paw edema were also employed to verify the anti-inflammatory effect of the identified fraction. To explore the mechanism of action, the activity of inducible nitric oxide synthase (iNOS) and the level of nitric oxide (NO) in sera, as well as mRNA expression level of cyclo-oxygenase-2 (COX-2) in inflammatory tissues of rats with carrageenan-induced hind paw edema were measured. GC-MS technology was applied to identify the active components in the active fraction. RESULTS AND CONCLUSIONS The petroleum ether fraction (PEF) was identified to be the active fraction in inflammation animal models (i.e., oral administration of PEF (168.48, 42.12 and 10.53 mg/kg) evoked a significantly (P<0.001) dose-dependent inhibition of the xylene-induced mice ear edema). Down-regulating COX-2 expression (P<0.001) and reducing NO production (P<0.05) through inhibiting iNOS activity (P<0.001) may be the partial mechanism of action of PEF. GC-MS analysis indicated that unsaturated fatty acids are enriched in PEF and may be responsible for the anti-inflammatory activity of PEF and this herb. The results of this study provide pharmacological and chemical basis for the application of the hip of R. multiflora Thunb. in inflammatory disorders.

Xanthones from the roots of Cudrania fruticosa Wight.

Chemical investigation on the roots of Cudrania fruticosa resulted in the isolation of two new xanthones, 1,6,7-trihydroxy-2-(1,1-dimethyl-2-propenyl)-3-methoxyxanthone (1) and 3,6,7-trihydroxy-1-methoxyxanthone (2), together with three known ones, 1,3,5-trihydroxy-4-(3-hydroxy-3-methylbutyl)xanthone (3), 1,3-dihydroxy-6,7-dimethoxyxanthone (4) and 3,5,6-trihydroxy-1-methoxyxanthone (5), respectively. Their structures were elucidated on the basis of spectral and chemical techniques.

Two new cardenolides from the roots of Streptocaulon griffithii

Two new cardenolides, 3β,5β,14β-trihydroxyl-card-16,20(22)-dienolide (1) and 3-O-β-d-glucopyranosyl-5β,14β-dihydroxyl-card-16,20(22)-dienolide (2), together with seven known compounds identified as digitogenin (3), 16-O-acetylgitoxigenin (4), periplogenin (5), 16-O-acetylperiplogenin (6), periplogenin digitoxoside (7), periplogenin-3-O-β-d-glucopyranoside (8) and periplogenin-3-O-β-d-glucopyranosyl-(1 → 4)-O-β-d-digitoxopyranoside (9) were isolated from the roots of Streptocaulon griffithii. Their structures were elucidated on the basis of spectroscopic data.

Two new antioxidant diarylheptanoids from the fruits of Alpinia oxyphylla

Two new diarylheptanoids, 1-(3′,5′-dihydroxy-4′-methoxyphenyl)-7-phenyl-3-heptanone (1) and 1-(2′,4′-dihydroxy-3′-methoxyphenyl)-7-(4″-methoxyphenyl)-3-heptanone (2), along with known diarylheptanoid yakuchinone A (3), and five flavanoids, tectochrysin (4), chrysin (5), izalpinin (6), kaempferol 7, 4′-dimethyl ether (7), and kaempferide (8) were isolated from the fruits of Alpinia oxyphylla Miq. Their structures were determined by means of spectroscopic methods. Antioxidant activities of all the isolated compounds were evaluated using a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Compounds 1–3 and 6–8 exhibited potent antioxidant activities in the DPPH assay.

A new cerebroside from Uvaria tonkinensis var. subglabra

A new cerebroside, subglain A (1), together with five known compounds (2–6) have been isolated from the stems of Uvaria tonkinensis var. subglabra. The structure of 1 has been determined to be 1-O-β-D-glucopyranosyl-(2S,3S,4R,8Z,2′R)-2-[N-(2′-hydroxytetracosanyl)-N-(1″,2″-dihydroxyethyl)-amide]-8-tetradecene-1,3,4-triol by spectroscopic evidence. The known compounds were identified as schisandriside (2), erythritol (3), β-D-glucopyranose (4), kaempferol-3,7-O-α-L-dirhamnoside (5), and (+)-lyoniresinol (6).

Two new triterpene saponins from Lysimachia capillipes.

Two new saponins, capilliposide G (1) and capilliposide H (2), were isolated from the whole plants of Lysimachia capillipes. Their structures were determined by 1D and 2D NMR, MS technique and chemical methods.

Two forms of long-term potentiation induced by different compounds

The purpose of this study was to investigate different forms of long-term potentiation (LTP) induced by different compounds. As shown in results, the influx of calcium via voltage-dependent calcium channels (VDCCs) was responsible for ( − )-clausenamide-induced LTP in hippocampus, while Rg1 induced LTP is mediated by the entry of calcium via N-methyl-d-aspartate glutamate (NMDA) receptor. The findings in the present study provide pharmacological basis for the nootropic mechanisms of these two compounds.