Ke Zan

Triterpene Saponins from Clematis chinensis and Their Potential Anti-inflammatory Activity

Seven new triterpene saponins, clematochinenosides A-G (1-7), together with 17 known saponins (8-24), were isolated from the roots and rhizomes of Clematis chinensis. Their structures were elucidated on the basis of spectroscopic evidence and hydrolysis products. Compounds 1, 3-7, and 20-24 showed inhibitory activities against COX-1 and COX-2 enzymes.

Dimeric guaianolides and sesquiterpenoids from Artemisia anomala.

A new dimeric guaianolide (8) and a new glaucolide (3), a seco-guaiaretic acid (4), two guaianolides (6 and 7), and five known sesquiterpene lactones (1, 2, 5, 9, and 10) were isolated from the aerial part of Artemisia anomala. Their structures were determined on the basis of chemical and spectroscopic analysis. In addition, their cytotoxic activities against five human cancer cell lines and anti-COX-2 effects in vitro were evaluated.

Quinolone alkaloids with antibacterial and cytotoxic activities from the fruits of Evodia rutaecarpa.

Five new quinolone alkaloids, euocarpines A-E (16-20), four new natural products (1, 4, 12, and 14), and eleven known natural products were isolated from the fruits of Evodia rutaecarpa (Juss.) Benth. The structures of the new compounds were elucidated based on spectroscopic evidence. All compounds were evaluated for their antibacterial activity against three strains and for their cytotoxic activity against four human tumor cell lines. The results revealed that 5, 7-11, 13, 14, and 16-20 exhibited moderate antibacterial activities (MIC values: 4-128 μg/mL), and 9, 11, 14, and 17 exhibited moderate cytotoxic activities against HepG-2, Hela, BEL7402, and BEL7403 (IC50 values: 15.85-56.36 μM).

Three new triterpene saponins from Clematis chinensis

Three new triterpene saponins, clematochinenosides H–J (1–3), were isolated from the roots and rhizomes of Clematis chinensis. Their structures were elucidated on the basis of spectroscopic means including 1D and 2D NMR experiments and hydrolysis products.

A rapid and sensitive HPLC-MS/MS analysis and preliminary pharmacokinetic characterization of sibiricaxanthone F in rats.

A simple, rapid and sensitive liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for quantifying sibiricaxanthone F (SF) in rat plasma following oral and intravenous dosings. After addition of the internal standard (IS) kaempferol and the antioxidant, 20% ascorbic acid, plasma samples were precipitated with acetonitrile and separated on an Aglient Zorbax XDB-C(18) column (50 mm × 4.6mm I.D., 2.1 μm) with gradient acetonitrile and water (both containing 0.01% formic acid) as the mobile phase. The detection was performed on a Sciex API 4000 LC-MS/MS with electrospray ionization (ESI) inlet in the negative multiple reaction monitoring (MRM) mode. Good linearity was achieved over the concentration range of 0.5-500.0ng/mL (r>0.996). Intra- and inter-day precisions were less than 7.60%, and accuracy ranged from 97.18% to 99.84%. The lower limit of quantification for SF was 0.5 ng/mL, and analytes were stable under various conditions (during freeze-thaw, at room temperature and under deep-freeze conditions). This validated method was successfully applied to the preliminary pharmacokinetic study of SF in rats for the first time, and the absolute bioavailability of SF was found to be only 0.22 ± 0.15%.

Prostaglandin-like fatty acid derivatives from Artemisia anomala

Four prostaglandin-like fatty acid derivatives anomalone A–D (1–4) were isolated from the aerial part of Artemisia anomala S. Moore. Their structures were determined on the basis of extensive spectroscopic analyses.

Qualitative and quantitative evaluation of Microctis Folium (the leaves of Microcos paniculata L.) by high performance liquid chromatography coupled with diode array detection and electrospray ionization tandem mass spectrometry

Microctis Folium (MF), the leaves of Microcos paniculata L., which is widely used as a traditional Chinese medicine and a healthy tea, show various biological activities including antioxidant, cardiovascular risk, and so on. However, few studies on the quality control for this herbal medicine have been reported. In this paper, a reliable and sensitive online high-performance liquid chromatography coupled with diode array detection and electrospray ionization tandem ion trap mass spectrometry (HPLC-DAD-ESI-MS/MS) method for qualitative and quantitative evaluation of the characteristic chemical constituents of MF was developed. 32 compounds including 10 flavans, 16 flavonoid glycosides, 5 lignan glycosides and 1 megastigmadien glycoside were identified from MF, among which lignan glycosides and megastigmadien glycoside were first reported from the genus Microcos. Besides, based on HPLC-DAD-ESI-MS/MS data, a standardized HPLC fingerprint and a quantitative method were established by analyzing 13 batches of commercial herbal samples by HPLC with ultraviolet-visible (UV) detection method. Meanwhile, three major bioactive constituents including kaempferol-3-O-β-D-glucoside, narcissi and isorhamnetin-3-O-β-D-glucoside in MF were simultaneously determined with the same method, which could differentiate good quality batches from counterfeits. The results revealed that this HPLC-DAD-ESI-MS/MS analytical method established could be adopted as the comprehensive quality control method of MF.