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111.
干旱胁迫对丹参叶片气体交换和叶绿素荧光参数的影响 总被引:8,自引:2,他引:6
研究了干旱处理15d后,大叶型丹参和小叶型丹参2个品种幼苗气体交换和叶绿素荧光参数的变化.结果表明:在干旱胁迫15d后,大叶型丹参叶片净光合速率(Pn)和PSⅡ最大光化学效率(Fv/Fm)分别下降了66.42%和10.98%,而小叶型丹参的Pn和Fv/Fm分别下降了29.32%和5.47%,干旱胁迫对大叶型丹参Pn和Fv/Fm的影响明显大于小叶型丹参.小叶型丹参Pn下降主要由气孔因素造成,而大叶型则主要由非气孔因素所致.干旱胁迫使丹参叶片的气孔导度(Gs)下降,但明显诱导了水分利用效率(WUE)、非光化学猝灭系数(qN)和光呼吸速率与净光合速率比率(Pr/Pn)的增加,以提高干旱胁迫抗性.其中小叶型丹参的增幅明显大于大叶型丹参.表明小叶型丹参的抗干旱胁迫能力更强. 相似文献
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114.
Two naphthoquinone diterpenoids, 1 and 2, one tricyclic, and one tetracyclic rearranged abietane ('4,5-seco-10,5-friedo-abietane') diterpenoids, 3 and 4, respectively, together with horminone (5) have been isolated from the roots of Salvia sahendica. Compounds 2 and 3 are new, and the 13C-NMR assignment for compound 4 was modified using ' Heteronuclear Multiple-Bond Correlation' (HMBC) spectroscopic data. The structures of the compounds have been established by using different spectral data including 1D- and 2D-NMR, IR, UV, and MS. The elemental composition for the major peaks of 3 and 4 were determined by ' High-Resolution Electron Impact Mass Spectrometry' (HR-EI-MS). The relative configurations of the new compounds were determined by 1H-NMR and 'Rotating-Frame NOES' (ROESY) spectroscopy. Compounds 1, 2, and 5 showed antifungal activities when tested on Blakeslea trispora. Lapachol, a prelynated naphthoquinone, was used as a positive control. The biological activities of the related naphthoquinones and abietane diterpenoids were discussed. 相似文献
115.
When Ti transformed Salvia miltiorrhiza cells werecultured in a MS-NH4 medium (MS without ammonium nitrate, containing30 g/L sucrose) at 25 °C in darkness for 18d, the total tanshinone (cryptotanshinone and tashinone IIA)contents in cultures were 12.23 mg/L and 15.07 mg/Lfor yeast elicitor (4 g/L), and yeast elicitor plus 200mol/L salicylic acid (SA) treated cultures, respectively,whereas only trace amounts of tanshinone were detected in the control or SAtreated cells. To explore the hormonal background concerning these phenomena,endogenous phytohormones were determined using ELISA kits. We found that ABA andiPAs contents in yeast elicitor plus SA treated cell cultures were increased 2.8to 9.8-fold and 3.6 to 5.8-fold respectively, while contents of GA1and IAA were decreased by 13.2%–56.9% and 34.8%–74.6% respectively.This suggests that higher levels of ABA and iPAs combined with lower levels ofGA1 and IAA inhibit the growth of cells, then probably stimulate thetanshinone production. 相似文献
116.
Protective effects of Danshensu from the aqueous extract of Salvia miltiorrhiza (Danshen) against homocysteine-induced endothelial dysfunction 总被引:10,自引:0,他引:10
Homocysteine (Hcy) is a by-product of methionine metabolism. An imbalance of Hcy in the body may lead to hyperhomocysteinemia, a condition with elevated Hcy concentration in blood that may be one of the risk factors responsible for the development of several vascular diseases (thromboembolism, atherosclerosis, stroke, vascular diseases and dementia). Radix Salvia miltiorrhiza (Danshen), a well-known Chinese medicinal herb that can activate and improve blood microcirculation, is noticeable for its beneficial effect in treating cardiovascular diseases. The present study is to demonstrate the protective effect of Danshen extract against the homocysteine-induced adverse effect on human umbilical vein endothelial cell (HUVEC). Homocysteine (5 mM) not only decreased the cell viability but also caused the disruption of capillary-like structure formation in vitro. The protective effect of Danshen aqueous extract and its active compounds on endothelial cell function were demonstrated through an in vitro tube formation assay, which mimics the new blood vessel formation. To identify the active components in the aqueous extract of Danshen, the content was characterized by instrumental analysis using high performance liquid chromatography with diode array detector (DAD) and electrospray tandem mass spectrometry (ESI-MS/MS). Interestingly, Danshen extract and its pure compounds showed different effectiveness in protecting HUVEC against Hcy-induced injury according to the following descending order: Danshen aqueous extract, 3-(3,4-dihydroxy-phenyl)-2-hydroxy-propionic acid (Danshensu), protocatechuic acid, catechin and protocatechualdehyde. We believed that such findings might provide evidence in understanding the beneficial effects of Danshen on the cardiovascular system. 相似文献
117.
A water-soluble polysaccharide complex (A) composed of galactose (17.9%), 3-O-methyl-galactose (3.0%), glucose (15.5%), mannose (8.3%), arabinose (30.4%), xylose (7.6%), fucose (2.6%), rhamnose (6.7%), and uronic acids (8.0%) has been isolated from the aerial parts of sage (Salvia officinalis L.) by cold water extraction. It showed a broad molecular-mass distribution pattern (Mw approximately 2000-93,000) with a predominance of polymers with Mw< 10,000. Ion-exchange chromatography of A afforded six polymeric fractions (A1-A6) in which arabinogalactans associated with galacturonan and/or rhamnogalacturonan backbones prevail. Sage polysaccharides were examined for their immunomodulatory activity in the comitogenic thymocyte test which is interpreted as being an in vitro correlate of adjuvant activity. The acidic polysaccharide fractions A2, A3 and A4 exhibited the highest mitogenic and comitogenic activities of all fractions tested, and relatively high SI(comit)/SI(mit) ratios approximately 3 indicate potential adjuvant properties of these polysaccharides. 相似文献
118.
Abietane diterpenoids and triterpenoic acids from Salvia cilicica and their antileishmanial activities 总被引:2,自引:0,他引:2
Tan N Kaloga M Radtke OA Kiderlen AF Oksüz S Ulubelen A Kolodziej H 《Phytochemistry》2002,61(8):881-884
Bioguided-fractionation of an acetone extract of the roots of Salvia cilicica (Lamiaceae) led to isolation of two new diterpenes, 7-hydroxy-12-methoxy-20-nor-abieta-1,5(10),7,9,12-pentaen-6,14-dione and abieta-8,12-dien-11,14-dione (12-deoxy-royleanone), together with oleanolic acid, ursolic acid, ferruginol, inuroyoleanol and cryptanol. Their structures were determined spectroscopically, which included HREIMS and 2D NMR spectroscopic analysis. The new abietane derivatives showed appreciable in vitro antileishmanial activity against intracellular amastigote forms of both Leishmania donovani (IC(50) values of 170 and 120 nM, respectively) and Leishmania major (IC(50) values of 290 and 180 nM, respectively). The triterpenoic acids were found to be potently active against amastigote (IC(50) values of 7-120 nM) and moderately active against promastigote stages (IC(50) values of 51-137 nM) of the two Leishmania species. 相似文献
119.
Xueying Huang Muxin Zhang Yu Song Bowen Sun Lin Lin Xiaoli Song Chao Li 《Journal of cellular and molecular medicine》2023,27(22):3514-3525
Salvia miltiorrhiza Bunge is a natural drug for treating myocardial infarction (MI). However, the targets and mechanisms of S. miltiorrhiza Bunge in the treatment of MI are yet to be elucidated. Traditional Chinese medicine systems pharmacology (TCMSP) data were used to screen out chemical constituents, and UniProt was used to predict relevant targets. Disease targets were obtained from the Online Mendelian Inheritance in Man and GeneCards databases. We used the STRING platform to build a protein–protein interaction network and used Cytoscape_v3.8.1 software to make a Drug–Ingredients–Gene Symbols–Disease network map. The Metascape database was used to perform gene ontology and Kyoto Encyclopaedia of Genes and Genomes (KEGG) enrichment analyses for drug–disease overlapping gene symbols. The targets identified by network pharmacology were further verified by in vitro and in vivo experiments. Seventy-five active components of S. miltiorrhiza Bunge were obtained from the TCMSP database, while 370 disease targets and 29 cross-targets were obtained from the Genecards database. The KEGG pathway enrichment results suggested that the mechanism of S. miltiorrhiza Bunge in the treatment of MI was significantly related to the VEGF signalling pathway. In vitro and in vivo experiments were used to evaluate the reliability of some important active ingredients and targets. S. miltiorrhiza Bunge alleviated the damage to cardiac function, attenuated myocardial fibrosis and protected endothelial cell function by increasing the expression of TGF-β and VEGFA. S. miltiorrhiza Bunge showed the therapeutic effect of MI by promoting the expression of VEGFA signalling pathway, providing a reliable basis for exploring herbal treatment of MI. 相似文献
120.