Chemical characterization of a PD-1/PD-L1 inhibitory activity fraction of the ethanol extract from Gymnadenia conopsea.

Searching for PD-1/PD-L1 inhibitor from medicinal plants has become a potential method to discover small molecular cancer immunotherapy drugs. Using PD-1/PD-L1 inhibitory activity assay in vitro, a bioactive fraction was obtained from the ethanol extract of Gymnadenia conopsea. A sensitive UPLC-HRMS/MS method was established for the rapid screening and identification of compositions from bioactive fraction. Based on the characteristic fragmentation patterns of standards analysis and extracted ion chromatogram (EIC) method, 46 compounds were rapidly screened and identified (including 35 succinic acid ester glycosides and 11 other compounds), among which 17 compounds were tentatively identified as new compounds.

Rapid Characterizaiton of Chemical Constituents of the Tubers of Gymnadenia conopsea by UPLC-Orbitrap-MS/MS Analysis.

Gymnadenia conopsea R. Br. is a traditional Tibetan medicinal plant that grows at altitudes above 3000 m, which is used to treat neurasthenia, asthma, coughs, and chronic hepatitis. However, a comprehensive configuration of the chemical profile of this plant has not been reported because of the complexity of its chemical constituents. In this study, a rapid and precise method based on ultra-high performance liquid chromatography (UPLC) combined with an Orbitrap mass spectrometer (UPLC-Orbitrap-MS/MS) was established in both positive- and negative-ion modes to rapidly identify various chemical components in the tubers of G. conopsea for the first time. Finally, a total of 91 compounds, including 17 succinic acid ester glycosides, 9 stilbenes, 6 phenanthrenes, 19 alkaloids, 11 terpenoids and steroids, 20 phenolic acid derivatives, and 9 others, were identified in the tubers of G. conopsea based on the accurate mass within 3 ppm error. Furthermore, many alkaloids, phenolic acid derivates, and terpenes were reported from G. conopsea for the first time. This rapid method provides an important scientific basis for further study on the cultivation, clinical application, and functional food of G. conopsea.

New Iridoid Derivatives from the Fruits of Cornus officinalis and Their Neuroprotective Activities.

Three previously undescribed iridoids, cornusfurals A⁻C, were isolated from the ethanolic extracts of fruits of Cornus officinalis. Their structures were elucidated by spectroscopic methods, including one-dimensional and two-dimensional nuclear magnetic resonance, ultraviolet spectroscopy, infrared spectroscopy, and mass spectrometry. The neuroprotective activity was evaluated by measuring corticosterone-induced damage in PC12 cells. The results showed that cornusfural B decreased corticosterone-induced PC12 cell damage compared with that in model cells.

Three new ursane-type triterpenoids from Rosmarinus officinalis and their biological activities.

Three new ursane-type triterpenoids, 3-oxours-12-en-20, 28-olide (1), 3ß-hydroxyurs-12-en-20, 28-olide (2) and 3ß-hydroxyurs-11, 13(18)-dien-20, 28-olide (3), were isolated from a potent anti-inflammatory and antibacterial fraction of the ethanolic extract of Rosmarinus officinalis. Their structures were elucidated by a combination of extensive 1D- and 2D-NMR experiments, MS data and comparisons with literature reports. Compounds 1-3 exhibited significantly inhibitory effects on nitric oxide production in lipopolysaccharide-activated mouse RAW264.7 macrophages, but no antibacterial activity was found at a concentration of 128 µg·mL-1.

Secoiridoid glycosides from the fruits of Cornus officinalis.

Five new secoiridoid glycosides, cornusphenosides E-I (1-5), were isolated and characterized from an active fraction of ethanol extract of the fruits of Cornus officinalis. Their structures were determined by extensive spectroscopic data analysis, including 2 D NMR and HRESIMS experiments. In the preliminary assay, compound 5 (when evaluated at 10 µM) showed the neuroprotective effect against H2O2-induced SH-SY5Y cell damage.

Norursane-type triterpenoids from Rosmarinus officinalis and their anti-inflammatory activity evaluation.

Five norursane-type triterpenoids, including three novel of 3ß-28-norursa-12,17,19,21-tetraene-3-ol (1), 3ß-28-norursa-12,20(30)-dien-3-ol (2) and 3ß-28-norursa-12,16,20(30)-triene-3-ol (3), as well as two known 3ß-28-norursa-17,19,21-trien-3-ol (4) and 3ß-28-norursa-12-ene-3-ol (5) were isolated from the ethyl acetate dissolved fraction of the ethanol extract from Rosmarinus officinalis. Their structures were elucidated by HR-ESI-MS, IR, 1D- and 2D-NMR spectroscopic methods. Compounds 1-5 exhibited significant inhibitory effect on NO production in LPS-activated RAW264.7 cells, and compounds 2, 3 and 5 shown better anti-inflammatory activity.

Polyhydroxylated sterols from Monascus purpureus-fermented rice.

Using a cell-based cytotoxicity assay, two new polyhydroxylated sterols, 16(S),22(S)-epoxy-3ß,5α,6ß,20(R),23(R),25-hexahydroxy-7-ergostene and 3ß,7ß,8α,25-tetrahydroxy-5,22E-ergostadiene were isolated from the ethyl acetate portion of the ethanolic extract of Monascus purpureus. Their structures were elucidated by spectroscopic analysis and in comparison with those reported in the literature. Both compounds showed cytotoxic activity against the lung adenocarcinoma (A549) with IC50 values of 12.6 and 18.5 µM, exhibited moderate activities against human ovarian cancer (A2780), with IC50 values of 8.8 and 9.4 µM.

Taraxastane-type triterpenoids from the medicinal and edible plant Cirsium setosum.

Guided by TNF-α secretion inhibitory activity assay, four taraxastane-type triterpenoids, including two new ones, 22-oxo-20-taraxasten-3ß, 30-diol (1) and 22α-hydroxy-20-taraxasten-30ß, 30-triol (2), have been obtained from an active fraction of the petroleum ether-soluble extract of the the medicinal and edible plant Cirsium setosum. Their structures were elucidated by spectroscopic data and CD data analysis. In the TNF-α secretion inhibitory activity assay, compounds 1 and 2 were active with the IC50 of 2.6 and 3.8 µmol·L-1, respectively. In addition, compounds 1 and 2 showed moderately selective cytotoxicity against the human ovarian cancer (A2780) and colon cancer (HCT-8) cell lines.