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1.
用水蒸气蒸馏法提取白花丹参与紫花丹参干燥根挥发油,用气相色谱-质谱(GC/MS)联用法进行了分析测定,分别鉴定出43种和18种成分,占挥发油色谱总峰面积的84.55%和79.69%,其中共有组分为11种。白花丹参相对质量分数较高的组分为蛇麻烷(27.78%)、合铁锈醇(26.13%)和1R-[1.α(R*),4a,8aα]-α-乙烯基十氢-α,5,5,8a-四甲基-2-亚甲基,1-萘丙醇(17.37%),而紫花丹参相对质量分数较高的组分为合铁锈醇(44.39%)和7-异丙基-1,1,4a-三甲基-1,2,3,4,4a,9,10,10a-八氢菲内酯(23.41%)。实验表明,白花丹参与紫花丹参挥发油中化学成分差别很大。  相似文献   

2.
A simple and sensitive HPLC method to detect tanshinone I, tanshinone IIA, and cryptotanshinone in human urine was developed and validated. Chromatographic separation was achieved on a C18 column (4.6 mm × 250 mm, 5 µm) using a mixture of methanol/water (78:22 v/v, containing 0.5% acetic acid) as the mobile phase at a flow rate of 0.5 mL/min with UV detector at 254 nm. The calibration curve of tanshinones was linear over a range of 1.0 × 10−4 – 1.0 mg/mL. The limit of quantification (LOQ) was found to be 57.0, 76.0, and 45.0 ng/mL, respectively. This method can estimate the pharmacokinetic parameters of tanshinones in human urine after the intravenous and intraperitoneal administration of stanchions.  相似文献   

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Salvia miltiorrhiza has been an economically important medicinal plant. Previously, an S. miltiorrhiza mitochondrial genome (mitogenome) assembled from Illumina short reads, appearing to be a single circular molecule, has been published. Based on the recent reports on the plant mitogenome structure, we suspected that this conformation does not accurately represent the complexity of the S. miltiorrhiza mitogenome. In the current study, we assembled the mitogenome of S. miltiorrhiza using the PacBio and Illumina sequencing technologies. The primary structure of the mitogenome contained two mitochondrial chromosomes (MC1 and MC2), which corresponded to two major conformations, namely, Mac1 and Mac2, respectively. Using two approaches, including (1) long reads mapping and (2) polymerase chain reaction amplification followed by Sanger sequencing, we observed nine repeats that can mediate recombination. We predicted 55 genes, including 33 mitochondrial protein-coding genes (PCGs), 3 rRNA genes, and 19 tRNA genes. Repeat analysis identified 112 microsatellite repeats and 3 long-tandem repeats. Phylogenetic analysis using the 26 shared PCGs resulted in a tree that was congruent with the phylogeny of Lamiales species in the APG IV system. The analysis of mitochondrial plastid DNA (MTPT) identified 16 MTPTs in the mitogenome. Moreover, the analysis of nucleotide substitution rates in Lamiales showed that the genes atp4, ccmB, ccmFc, and mttB might have been positively selected. The results lay the foundation for future studies on the evolution of the Salvia mitogenome and the molecular breeding of S. miltiorrhiza.  相似文献   

4.
果壳生物质热解特性与动力学   总被引:1,自引:0,他引:1  
采用热重分析仪对林产果壳生物质(澳洲坚果壳、油茶壳、核桃壳)热解特性进行了研究,利用分布活化能模型(DAEM)分析了热解动力学。热解特性研究表明:油茶壳最大失重速率最小,热解起始温度、结束温度、最大失重速率温度均低于澳洲坚果壳和核桃壳;澳洲坚果壳和核桃壳热解特征值近似;3种果壳生物质随升温速率的增加,热解过程向高温区转移。DAEM研究表明:DAEM适用于3种果壳生物质的热解动力学研究,相关系数R2在0.914~0.999之间;澳洲坚果壳热解活化能83.91~211.86 kJ/mol,油茶壳热解活化能68.64~244.49 kJ/mol,核桃壳热解活化能98.69~267.75 kJ/mol;随转化率的增加,3种果壳生物质活化能呈现相同的变化趋势,但变化幅度不同。  相似文献   

5.
金莲花黄酮超声波提取的动力学模型   总被引:1,自引:0,他引:1  
以金莲花中黄酮提取量为考察指标,研究以体积分数50%的乙醇溶液为提取剂,超声波辅助提取金莲花总黄酮的传质动力学过程。根据质量平衡方程,利用实验测得的提取过程中的重要动力学和热力学参数,建立了金莲花黄酮超声波提取的动力学模型。结果表明:金莲花黄酮超声波提取过程为准一级反应,所建立的动力学模型能较好地描述金莲花黄酮的超声波提取过程。  相似文献   

6.
JAK inhibition is a new strategy for treating autoimmune and inflammatory diseases. Previous studies have shown the immunoregulatory and anti-inflammatory effects of Salvia miltiorrhiza and Cynara scolymus and suggest that the bioactivity of their phenolic acids involves the JAK-STAT pathway, but it is unclear whether these effects occur through JAK inhibition. The JAK binding affinities obtained by docking Rosmarinic acid (RosA), Salvianolic acid A (SalA), Salvianolic acid C (SalC), Lithospermic acid, Salvianolic acid B and Cynarin (CY) to JAK (PDB: 6DBN) with AutoDock Vina are −8.8, −9.8, −10.7, −10.0, −10.3 and −9.7 kcal/mol, respectively. Their predicted configurations enable hydrogen bonding with the hinge region and N- and C-terminal lobes of the JAK kinase domain. The benzofuran core of SalC, the compound with the greatest binding affinity, sits near Leu959, such as Tofacitinib’s pyrrolopyrimidine. A SalC derivative with a binding affinity of −12.2 kcal/mol was designed while maintaining this relationship. The docking results show follow-up studies of these phenolic acids as JAK inhibitors may be indicated. Furthermore, derivatives of SalC, RosA, CY and SalA can yield better binding affinity or bioavailability scores, indicating that their structures may be suitable as scaffolds for the design of new JAK inhibitors.  相似文献   

7.
Salvia miltiorrhiza Bunge has been widely used in the treatment of cardiovascular and cerebrovascular diseases, due to the pharmacological action of its active components such as the tanshinones. Plasma membrane (PM) H+-ATPase plays key roles in numerous physiological processes in plants. However, little is known about the PM H+-ATPase gene family in S. miltiorrhiza (Sm). Here, nine PM H+-ATPase isoforms were identified and named SmPHA1–SmPHA9. Phylogenetic tree analysis showed that the genetic distance of SmPHAs was relatively far in the S. miltiorrhiza PM H+-ATPase family. Moreover, the transmembrane structures were rich in SmPHA protein. In addition, SmPHA4 was found to be highly expressed in roots and flowers. HPLC revealed that accumulation of dihydrotanshinone (DT), cryptotanshinone (CT), and tanshinone I (TI) was significantly reduced in the SmPHA4-OE lines but was increased in the SmPHA4-RNAi lines, ranging from 2.54 to 3.52, 3.77 to 6.33, and 0.35 to 0.74 mg/g, respectively, suggesting that SmPHA4 is a candidate regulator of tanshinone metabolites. Moreover, qRT-PCR confirmed that the expression of tanshinone biosynthetic-related key enzymes was also upregulated in the SmPHA4-RNAi lines. In summary, this study highlighted PM H+-ATPase function and provided new insights into regulatory candidate genes for modulating secondary metabolism biosynthesis in S. miltiorrhiza.  相似文献   

8.
以提取丹参酚酸B为例,研究了内部沸腾法提取过程的动力学及其相关的热力学.以超声波辅助法提取作为对比,采用一种简单测定提取分配系数的方法,计算了提取过程中的传质系数k,提取过程的活化能及热力学函数△H,ΔS和ΔG.实验结果表明:在提取压力为-0.084 MPa、解吸剂乙醇浓度为50%、解吸20 min、提取用水量为物料的...  相似文献   

9.
托盘根中总多酚提取工艺及抗氧化活性研究   总被引:1,自引:0,他引:1  
以悬钩子属植物托盘根为研究对象,采用超声辅助乙醇提取托盘根中总多酚.通过对乙醇浓度、料液比、超声时间、超声温度4种影响因素进行考察,在单因素实验结果基础上,采用正交试验优化其最佳提取工艺,并对托盘根总多酚的抗氧化能力进行评价.结果表明,托盘根活性成分的最佳提取工艺为乙醇浓度60%、超声温度80℃、超声时间50 min、...  相似文献   

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The crystallization process of a new polyamide, nylon 1313, from the melt has been thoroughly investigated under isothermal and nonisothermal conditions. During isothermal crystallization, relative crystallinity develops in accordance with the Avrami equation with the exponent n ≈ 2 based on DSC analysis. Under nonisothermal conditions, several different analysis methods were used to elucidate the crystallization process. The Avrami exponent n is greater in the isothermal crystallization process, indicating that the mode of nucleation and the growth of the nonisothermal crystallization for nylon 1313 are more complicated, and that the nucleation mode might include both homogeneous and heterogeneous nucleation simultaneously. The calculated activation energy is 214.25 kJ/mol for isothermal crystallization by Arrhenius form and 135.1 kJ/mol for nonisothermal crystallization by Kissinger method, respectively. In addition, the crystallization ability of nylon 1313 was assessed by using the kinetic crystallizability parameters G. Based on this parameter, the crystallizability of many different polymers was compared theoretically. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1415–1422, 2007  相似文献   

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In the present research work, the effect of solvents, particle size, solvent/solid ratio, and temperature on the extraction efficiency of oregano (Origanum vulgare) and mustard (Brassica nigra) were investigated. The extraction process proceeded at a fast rate followed by a slower one. Particle size, solvent type, solvent/solid ratio and temperature had a positive effect on the extraction process, and maximum extraction was achieved by ethanol. Extraction kinetics was determined with a mathematical model derived from Fick's second law. The results were verified with Fick's diffusion model for extraction kinetics in all experiments, which provided the initial rate and extent of solid–liquid extraction. Antioxidant values were determined using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and 2, 2′-azino-Bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS). The extracts of O. vulgare and B. nigra prepared using ethanol showed optimal antioxidant activity.  相似文献   

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16.
粉煤灰酸浸提铝及其动力学   总被引:5,自引:0,他引:5  
对KF为助剂焙烧活化粉煤灰酸浸提铝过程进行了研究,考察了粉煤灰焙烧活化和盐酸浸出条件对粉煤灰中铝浸出率的影响及其浸出过程动力学. 结果表明,焙烧活化优化条件为:时间1 h、温度800℃、粉煤灰与KF质量比为20:4. 浸出温度90℃、浸出时间2 h、盐酸浓度4 mol/L、液固比4 mL/g的条件下,铝提取率达到92.46%. 粉煤灰烧结产物加热酸浸过程符合收缩未反应核模型,反应级数为0.3718,反应活化能为43.49 kJ/mol,过程速率为化学反应速率控制.  相似文献   

17.
分别采用水蒸气蒸馏、同时蒸馏萃取、超声、闪式、先超声后同时蒸馏萃取,先闪式后同时蒸馏萃取6种提取方法提取金莲花挥发油,运用GC-MS分析挥发油的成分,并进行单料烟加香试验。结果表明:①金莲花挥发油得率分别为0.20%、0.67%、2.31%、2.67%、0.82%、0.78%,分别鉴定出20、30、19、18、37、30种成分;其中β紫罗兰酮、二氢猕猴桃内酯等为主要的香气成分;超声和闪式提取方法虽然挥发油得率高,但是杂质也较多,先超声后同时蒸馏萃取的挥发油优于其他几种。②在烟丝中,添加适量金莲花挥发油,能提高卷烟烟气的香气质和香气量,降低刺激性,改善余味,先超声后同时蒸馏萃取的挥发油加香效果最好。  相似文献   

18.
This work presents a study for chemical leaching of sphalerite concentrate under various constant Fe3+concentrations and redox potential conditions. The effects of Fe3+ concentration and redox potentia...  相似文献   

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李晓航  刘红刚  路建洲  滕阳  张锴 《化工学报》2019,70(11):4397-4409
在固定床吸附反应器内对两台300MW等级燃煤发电机组循环流化床锅炉和煤粉锅炉飞灰样品进行气相零价汞吸附实验,通过改变实验工况研究温度、入口汞浓度和入口气体流量对飞灰汞吸附能力的影响。采用颗粒内扩散模型、准一阶和准二阶动力学模型、耶洛维奇(Elovich)模型对实验数据分别进行拟合,从动力学的角度探讨两种锅炉飞灰对气相零价汞吸附的影响机制以及两种锅炉飞灰与气相零价汞之间吸附动力学行为差异。结果表明:相同工况下循环流化床锅炉飞灰汞吸附过程的穿透时间和平衡吸附量远大于煤粉锅炉飞灰。吸附温度为150℃时,两种锅炉飞灰对气相零价汞的平衡吸附量最大。由于外扩散阻力随气体入口流量的增加而减小,入口汞浓度的增加可提高传质推动力,飞灰对汞的吸附得以增强。动力学分析表明飞灰的零价汞吸附由外扩散、内扩散和表面化学吸附共同控制,其中表面化学吸附是该吸附过程中的控制步骤;准二阶动力学模型和Elovich动力学模型更适合于描述该吸附过程。相同实验条件下,循环流化床锅炉飞灰吸附过程拟合所得的颗粒内扩散系数、准一阶动力学常数和初始吸附速率均大于煤粉锅炉飞灰。  相似文献   

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