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1.
Abstract

Two new lignans mubezhisol (1) and mubezhisal (2), together with twenty six known compounds (328) were isolated from water-soluble fraction from the semens of Momordica cochinchinensis. In the subsequent action evaluation, four saponins (4, 6, 13, 27), six lignans (1, 2, 16, 17, 22, 23), and one naphthoquinone (24) exhibited the significant cytotoxicity. The results indicated that various saponins and lignans were mainly responsible for the antitumor activities of Momordicae Semen.  相似文献   
2.
Dalbergia cochinchinensis has been widely used in traditional medicine because of its flavonoids; however, the impact of the flavonoids to modulate the inflammatory response to oral cells remains to be described. For this aim, we isolated 4,7,2′-trihydroxy-4′-methoxyisoflavanol (472T4MIF) and 6,4′-dihydroxy-7-methoxyflavane (64D7MF) from the heartwood of D. cochinchinensis and confirmed the chemical structure by nuclear magnetic resonance. We show here that both flavonoids are inhibitors of an inflammatory response of murine RAW 264.7 inflammatory macrophages stimulated by LPS. This is indicated by interleukin (IL)1, IL6, and chemokine CCL2 production besides the phosphorylation of p65. Consistently, in primary murine macrophages, both flavonoids decreased the inflammatory response by lowering LPS-induced IL1 and IL6 expression. To introduce oral cells, we have used human gingival fibroblasts and provoked the inflammatory response by exposing them to IL1β and TNFα. Under these conditions, 472T4MIF, but not 64D7MF, reduced the expression of chemokines CXCL1 and CXCL2. Taken together, we identified two flavonoids that can reduce the expression of cytokines and chemokines in macrophages and fibroblastic cells.  相似文献   
3.
A high‐performance liquid chromatographic (HPLC) method was developed for the simultaneous quantification of five major bioactive constituents in the stems of resiniferous Dracaena plants from China and Vietnam, as well as those in the related traditional Chinese medicinal preparations. A diode array detector with the wavelength of 330 nm was used to monitor resveratrol, 7,4′‐dihydroxyflavone and pterostilbene, while loureirin A and loureirin B were monitored at 280 nm. The five constituents were separated on an Agela SB C18 column by gradient elution using 0.008% (v/v) formic acid solution (A) and acetonitrile (B) as the mobile phase. The validation of the method included recovery, linearity, accuracy and precision (intra‐ and inter‐day variation). The range of recoveries of this method was 98.1–104.9%, with all the constituents showing good linearity (r2 > 0.9999). The accuracy and precision were satisfactory, with the overall intra‐ and inter‐day variation being less than 4%. The present method has been successfully applied for the determination of all five constituents in 21 related herbal samples including 10 D. cochinchinensis stem samples, seven D. cambodiana stem samples and four purchased medicinal preparations. The contents of these constituents were analyzed using principal component analysis, which can efficiently identify raw herb of Dracaena from different sources. The study may be considered helpful to the quality control of Dracena plants and its medicinal preparations. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
4.
Chemical investigation of the ethanol extract of the roots of Cudrania cochinchinensis led to the isolation of a new flavonoid, (6S,12S,13R)-1-methoxy cyanomaclurin (1), together with seven known compounds, 1,3,5-trihydroxy-4-(3′-hydroxy-3′-methylbutyl)xanthone (2), 1,3,6-trihydroxy-4-prenylxanthone (3), 1,3,6,7-tetrahydroxyxanthone (4), 1,3,5,6-tetrahydroxyxanthone (5), 1,3,6-trihydroxy-5-methoxyxanthone (6), resveratrol (7) and oxyresveratrol (8). The structure of compound 1 was elucidated on the basis of 1D and 2D NMR spectra and the HR-ESI-MS data. The absolute stereochemistry was deduced via Rh2(OCOCF3)4-induced CD and NOESY spectra.  相似文献   
5.
Three undescribed phenylpropanoid derivatives, including two new bibenzyl constituents (1–2), one new stilbene constituent (3), together with five known compounds stilbostemin F (4), dihydropinosylvin (5), 2-(4-hydroxyphenyl)ethyl benzoate (6), 1-(4-hydroxybenzoyl)ethanone (7), and 4-hydroxy-3-prenylbenzoic acid (8), were isolated from the tuber of Asparagus cochinchinensis. The structures of 1–8 were elucidated according to UV, IR, HRMS, 1D and 2D-NMR methods together with the published literature. All of the isolated compounds were assessed for anti-inflammatory activity by acting on lipopolysaccharide (LPS)-induced RAW 264.7 macrophage cells in vitro. The results showed that compounds 2 and 5 were found to inhibit the production of nitric oxide (NO) with the IC50 value of 21.7 and 35.8 µM, respectively. In addition, further studies found that compound 2 demonstrated concentration-dependent suppression of the protein expression of iNOS and exerted anti-inflammatory activity via the NF-κB signalling pathway. The present data suggest that phenylpropanoid derivatives from the tuber of A. cochinchinensis might be used as a potential source of natural anti-inflammatory agents.  相似文献   
6.
A new furost-20(22)-ene oligoglycoside named as aspacochioside C was isolated from the roots of Asparagus cochinchinensis (Lour.) Merr. Its structure was elucidated to be 26-O-β-D-glucopyranosyl-(25S)-5β- furost-20(22)-en-3β,26-diol-3-O-α-L-rhamnopyranosyl-( 1 →4)-β-D-glucopyranoside on the basis of spectroscopic techniques including 1D and 2D NMR experiments.  相似文献   
7.
Phytochemical investigation of the roots of Stemona cochinchinensis led to the isolation and structure elucidation of a new pyrido[1,2‐a]azepine‐type alkaloid, stemocochinamine ( 1 ), and of four new pyrrolo[1,2‐a]azepine‐type alkaloids, bisdehydrostemocochinine ( 2 ), isobisdehydrostemocochinine ( 3 ), neostemocochinine ( 4 ), and isoneostemocochinine ( 5 ), together with six known alkaloids. Their structures were established on the basis of extensive 1D‐ and 2D‐NMR analyses in combination with HR‐MS experiments.  相似文献   
8.
Dragon's blood is a famous traditional Chinese medicine produced from source plants under bio‐ or abio‐stress. Dracaena cochinchinensis (Lour.) S.C. Chen xylem (DX) is one of the most important sources of the medicine. In this work, a GC‐MS method was developed for analysis of the n‐hexane extracts of DX with resin (DXR) and without resin (DXW). The repeatability of the method was also investigated for a metabolite comparative study of the different xylems. About 80 components were detected, 26 of which were identified in both DXR and DXN. Three sesquiterpenes (τ‐cadinol, τ‐muurolon and α‐cadinol) were first discovered in Dracaena cochinchinensis (Lour.) S.C. Chen. The chromatographs of the two plant materials were compared and differences of compounds were found. It showed that phytosterols showed a dramatic rise in content, and sesquiterpenes were found to be synthesized in DXR. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
9.
Natural compounds have been recognized as valuable sources for anticancer drug development. In this work, different parts from Momordica cochinchinensis Spreng were selected to perform cytotoxic screening against human prostate cancer (PC-3) cells. Chromatographic separation and purification were performed for the main constituents of the most effective extract. The content of the fatty acids was determined by Gas Chromatography-Flame Ionization Detector (GC–FID). Chemical structural elucidation was performed by spectroscopic means. For the mechanism of the apoptotic induction of the most effective extract, the characteristics were evaluated by Hoechst 33342 staining, sub-G1 peak analysis, JC-1 staining, and Western blotting. As a result, extracts from different parts of M. cochinchinensis significantly inhibited cancer cell viability. The most effective stem extract induced apoptosis in PC-3 cells by causing nuclear fragmentation, increasing the sub-G1 peak, and changing the mitochondrial membrane potential. Additionally, the stem extract increased the pro-apoptotic (caspase-3 and Noxa) mediators while decreasing the anti-apoptotic (Bcl-xL and Mcl-1) mediators. The main constituents of the stem extract are α-spinasterol and ligballinol, as well as some fatty acids. Our results demonstrated that the stem extract of M. cochinchinensis has cytotoxic and apoptotic effects in PC-3 cells. These results provide basic knowledge for developing antiproliferative agents for prostate cancer in the future.  相似文献   
10.
A new compound, Cochinchin (1), together with 7,4‘-dihydroxyflavone (2), 7-hydroxy-4‘-methoxyflavane (3),7-hydroxy-3-(4-hydroxybenzyl)chroman (4), 4‘-hydroxy-2,4-dirnethoxydihydrochalcone (5) and 4‘-hydroxy-2,4,6-trimethoxydihydrochalcone (6) was isolated from the resin (trivial name, “dragon‘s blood“) of Dracaena cochinchinensis (Lour.) S. C. Chert. The structure of 1 was elucidated on the basis of spectroscopic data as (2,3-trans)-6-allyl-2-(3,5-dimethoxyphenyl)-3-(4-hydroxyphenyl)-2,3-dihydrobenzo[1,4]dioxin which is a natural product possessing a new framework.  相似文献   
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