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1.
Linear bis dithiocarbamates are conveniently obtained from symmetrical disubstituted α,ω-alkanediamines whose preparation is reported.  相似文献   
2.
江苏南通地衣   总被引:1,自引:0,他引:1  
本文报导了江苏省南通市南郊公园及狼山等地地衣20属31种。其中中国新记录1种,Lepraria cfmembranacea;大陆新记录1种,Caloplaca cinnabarine;华东新记录4种,即B(?)ellia protothallina,Lecanora pulicaris,Lepraria incana,Parmelinarhytidodes;江苏新记录1种,Pertusaria Commutata.  相似文献   
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Two new sesquiterpenes, daedaleanols A (1) and B (2), together with three known sesquiterpenes (35), were isolated from cultures of the basidiomycete Daedalea incana. Their structures were elucidated on the basis of extensive spectroscopic means. All compounds were tested for their cytotoxicities against three human cancer cell lines.  相似文献   
5.
三种药剂对紫罗兰的矮化效应   总被引:1,自引:0,他引:1  
应用PP333、矮丰和水杨酸对紫罗兰进行叶面喷施处理,研究其对株高、花期、叶片长宽比、叶绿素含量的影响.结果表明:经PP333处理的紫罗兰株型明显矮化,经水杨酸处理的紫罗兰花期显著延长,初花期提前,但矮化效果不显著.综合效果看,叶面喷施质量浓度为0.2 mg/L的PP333对紫罗兰的作用效果较好(株高极显著矮化且未发生莲座化现象).叶面喷施水杨酸对提高紫罗兰叶绿素含量的影响最大.  相似文献   
6.
采用常压水蒸气蒸馏法提取了兰香草挥发油,得油率为0.35%~0.52%.其相对密度为(20℃)0.9980~0.9900,折射率为(20℃)1.4608,比旋光度为 0.51^*,酸值为1.5,并用毛细管气相色谱、红外光谱、核磁共振谱和色-质联机等对该挥发油进行了系统的成分分析.在分出的112个色谱峰中,共鉴定出71个化合物,占挥发油总量的94.6%.其主要成分为芳樟醇、紫苏醇、香芹酮、荠芋烯、4-甲基-6-庚烯-3-酮、菉草烯、马鞭草烯酮、左旋松香芹酮、2-壬烯-4-炔等。  相似文献   
7.
Quercusides A and B, new flavonoid glucosides have been isolated from the chloroform soluble fractions of Quercus incana. Their structures were assigned from 1H and 13C nuclear magnetic resonance spectra, distortionless enhancement by polarization transfer (DEPT) and by correlation spectroscopy, heteronuclear multiple quantum correlation (HMQC) and heteronuclear multiple bond correlation (HMBC) experiments. Lupeol, β‐sitosterol and ursolic acid have also been reported from this species. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
8.
紫罗兰与桂竹香原生质体培养及电激细胞融合的研究   总被引:7,自引:0,他引:7  
采用电激细胞融合的方法 ,对紫罗兰MatthiolaincanaR Br与桂竹香CheiranthuscheiriL 原生质体培养及电激细胞融合效率导入最适条件作了探讨。紫罗兰的子叶原生质体分裂初期培养最适条件 :培养基为 1 2MS。培养基组成中 ,蔗糖质量分数为 4%、甘露糖醇浓度为 0 6mol L。加入谷酰胺酶无机态氮源时 ,效果明显。次之 ,加入植物生长调节物质 1mg LBA也达到高分裂率。再者 ,添加玉米素时效果也甚好。根据原生质分离前的子叶在 5℃预处理分裂率最高 ,培养温度 2 4~ 30℃为宜。电激细胞融合 (singlepairs)产生效率高的条件为 :紫罗兰原生质体密度 1× 10个 mL ,高周波电强度 1MHz ,15 0V cm ,脉冲幅 70 μs;桂竹香原生质体密度 1× 10个 mL高周波电强度 1MHz,10 0V cm ,脉冲幅 30 μs。  相似文献   
9.
The work is aimed at phytochemical characterization and In Vitro evaluation of antioxidant actions, anti-inflammatory effects, and cytotoxicity of purified extracts from three rupturewort (Herniaria L.) species, i.e., Herniaria glabra (HG), H. polygama (HP), and H. incana herb (HIh). The total phenolic content established in the purified extracts (PEs) of HIh, HP, and HG was 29.6, 24.0, and 13.0%, respectively. Thirty-eight non-saponin metabolites were identified using LC-HR-QTOF-ESI-MS; however, only 9 were common for the studied Herniaria species. The most abundant phenolic compound in HG-PE was narcissin (7.4%), HP-PE shared 3 major constituents, namely cis-2-hydroxy-4-methoxycinnamic acid 2-O-β-glucoside (cis-GMCA, 5.8%), narcissin (5.4%), and rutin (5.3%). Almost half of HIh phenolic content (14.7%) belonged to oxytroflavoside A (7-O-methylkaempferol-3-O-[3-hydroxy-3-methylglutaryl-(1→6)]-[α-rhamnopyranosyl-(1→2)]-β-galactopyranoside). Antioxidant properties of the Herniaria PEs were evaluated employing an experimental model of human blood plasma, exposed to the peroxynitrite-induced oxidative stress. The assays demonstrated significant reduction of oxidative damage to protein and lipid plasma components (estimated by measurements of 3-nitrotyrosine, protein thiol groups, thiobarbituric acid-reactive substances), and moderate protection of its non-enzymatic antioxidant capacity. Anti-inflammatory properties of the Herniaria PEs were evaluated In Vitro as inhibitory effects against cyclooxygenases (COX-1 and -2) and concanavalin A-induced inflammatory response of the peripheral blood mononuclear cells (PBMCs). None of the studied plants showed inhibitory effects on COXs but all purified extracts partly reduced the release of interleukin 2 (IL-2) and tumor necrosis factor-alpha (TNF-α) from PBMCs, which suggested their prospective ability to up-regulate inflammatory response of the cells. The purified extract from H. glabra turned out to be the most efficient suppressor of PBMCs’ inflammatory response. Additionally, cytotoxicity of purified Herniaria extracts on PBMCs was ruled out based on In Vitro studies.  相似文献   
10.
Mussaenda incana Wall (Rubiaceae), an endemic medium sized tree of semi-forest regions of North Eastern States of India, is used in traditional medicine as detergent to ulcers and treatment of white leprosy1. Earlier we reported some terpenoids and iridoi…  相似文献   
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