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塔拉单宁水解废液回收奎尼酸的工艺试验 总被引:3,自引:0,他引:3
从塔拉单宁水解制备没食子酸的废液着手,用真空蒸发法分离去除盐酸,用不同的溶剂萃取法分离去除没食子酸,用活性炭吸附法和强碱阴离子交换法分离去除色素和糖类物质。从而提出了从塔拉单宁水解废液中回收目标产品奎尼酸的方法,产品得率约为理论值的78%。 相似文献
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五倍子制备没食子酸的研究进展 总被引:3,自引:0,他引:3
没食子单宁是没食子酸与多元醇制成的酯,易在酸、碱、酶的催化作用下水解,由此可制备多种与没食子酸相关的衍生物.以五倍子为原料提取没食子酸的方法有化学法和生物法两种,与化学水解法相比,生物法最显著的特点是水解完全,水解副产物葡萄糖可作为能源与碳源被生物催化剂代谢,不仅提高了资源的有效利用率,而且发酵废液易于处理,有利于环境保护. 相似文献
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分别采用紫外法和皮粉法对5种不同含量的塔拉单宁进行对比研究,并利用SPSS软件对单宁含量测定结果进行显著性检验,结果表明:高纯度塔拉单宁(93%)分别用紫外法和皮粉法测定单宁含量时实验结果并未显著差异(P>0.05),而4种纯度为60%左右塔拉单宁的实验结果均具有显著性差异(P<0.05),皮粉法测得的单宁含量均比用紫外法测得的结果高,差值约为1.5%~2.0%,并由此计算出紫外法测定塔拉单宁含量计算公式中的矫正常数p为1.03。紫外-可见吸收光谱与HPLC分析结果表明:塔拉单宁与五倍子单宁的最大吸收峰均为276 nm,同质量浓度下塔拉单宁的吸收峰强度高于五倍子单宁,塔拉单宁成分出峰时间主要在20~40 min,五倍子单宁主要在30~45 min。 相似文献
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二、五倍子单宁的水解水解是没食子酸生产的主要工序,也是决定产品收率、成本高低的关键。 1.水解的原理及其影响因素五倍子单宁由没食子酰基与β-D-葡萄糖以酯键连接而成。在酸或酶的作用下,酯键很容易断裂分解成没食子酸和葡萄糖。 相似文献
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本文介绍由倍花上分离的1株黑曲霉(Aspergillusniger-31)酶解五倍子单宁生物转化制没食子酸试验结果。倍花料通常的实际产品没食子酸的单宁转化率的63.5%,角倍料约74.5%;如适当改变条件,产品的单宁转化率可分别增至78.5%与89.5%左右,迄今中外有关文献现尚未见超过本研究单宁转化率的报告。 相似文献
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塔拉粉直接合成3,4,5—三甲氧基苯甲醛 总被引:1,自引:0,他引:1
直接以塔拉粉为起始原料,通过甲基化、水解、酯化、肼化、氧化制得3,4,5-三甲氧基苯甲醛,经波谱测定确证其结构与用五倍子合成的3,4,5-三甲氧基苯甲醛一致。产品成本比用五倍子单宁为原料每吨降低1.5万元。 相似文献
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天然植物单宁是指分子量为500~3000,在制革过程中能与动物生皮胶原结合的多酚化合物。植物单宁分水解和凝缩两大类。桔单宁不仅在制革方面具有商用价值,还可以作为生产没食子酸的原料。化学工业和制药工业以没食子酸作合成中间体。人们最为熟知的桔单宁是土耳其倍子单宁,这是山毛榉科染色栎(Quercus infectoria)上获得的一种病理赘瘤,可作药用单 相似文献
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在日本,富含单宁的野桐(Mallotus japonicus)(大戟科植物)的皮和叶,被用来治疗胃溃疡病。本报告作者已从中分离出一种新的称之为野桐精酸(mallotusinic acid)(1)的水解类单宁,以及野桐宁(geraniin)(2)作为叶子的主要成份,另外也发现了一种新的水解类单宁,称之为野桐亭酸(mallotinic acid)(3)。其方法是:将叶子在丙酮和水的混合物中搅匀,再用醋酸乙酯提取浓溶液。用上行滴入逆流色层法,并用正丁醇-醋酸-水(4:1:5)展开剂来分离醋酸乙酯提出物。夹杂有野桐宁的野桐精酸是继芸香甙和野桐宁之后的组份中分离得到的。用醋酸乙酯提取,调 相似文献
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Grandjean C Angyalosi G Loing E Adriaenssens E Melnyk O Pancré V Auriault C Gras-Masse H 《Chembiochem : a European journal of chemical biology》2001,2(10):747-757
The mannose receptor mediates the internalization of a wide range of molecules or microorganisms in a pattern recognition manner. Therefore, it represents an attractive entry for specific drug, gene, or antigen delivery to macrophages and dendritic cells. In an attempt to design novel effective synthetic mannose receptor ligands, quinic and shikimic acid were selected as putative mannose mimics on the basis of X-ray crystallographic data from the related rat mannose-binding lectin. As the mannose receptor preferentially binds to molecules displaying several sugar residues, fluorescein-labeled cluster quinic and shikimic acid derivatives with valencies of two to eight were synthesized. Their mannose receptor mediated uptake was assayed on monocyte-derived human dendritic cells by cytofluorimetric analysis. Mannose-receptor specificity was further assessed by competitive inhibition assays with mannan, by confocal microscopy analysis, and by expression of the mannose receptor in transfected Cos-1 cells. Constructs derived from both quinic and shikimic acid were efficiently recognized by the mannose receptor with an optimum affinity for the molecules with a valency of four. As a result, commercially available quinic and shikimic acids appear as stable mannose bioisosteres, which should prove valuable tools for specific cell delivery. 相似文献
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《分离科学与技术》2012,47(11):1667-1680
ABSTRACT Forward extraction of shikimic and quinic acids with tridodecylamine (TDA)/1-heptanol is favored at low temperature. In back extraction, higher temperatures and the addition of oleic acid as a competitive displacer provided 80% recovery for shikimic acid and 70% recovery for quinic acid. Higher recoveries are possible since these valuesare limited by the forward extraction step. The effect of temperature swing on carboxylic acid extraction by amines is primarily due to the change in amine basicity with temperature. The addition of a displacer lowers the energy cost by lowering the temperature required in back extraction. 相似文献
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Solvent extraction using an extractant/diluent system was evaluated for the recovery of shikimic and quinic acids. Tridodecylamine (TDA) was used as the extractant, and 1-heptanol as the diluent. TDA complexes with the acid resulting in an acid-amine complex, which is solvated by the alcohol diluent. In back extraction, oleic acid was added to the organic phase as a displacer. Oleic acid competitively displaces the carboxylic acid in the acid-amine complex, thus forming a displacer-amine complex. The distribution coefficient for back extraction by competitive displacement increased by at least an order of magnitude depending on the mole to mole ratio of oleic acid to TDA
Based on results from batch extraction experiments, a mass-action analysis was introduced for modeling forward and back extraction. The mass-action analysis served as a tool for understanding the mechanism of the extraction process. 相似文献
Based on results from batch extraction experiments, a mass-action analysis was introduced for modeling forward and back extraction. The mass-action analysis served as a tool for understanding the mechanism of the extraction process. 相似文献
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Liang-Liang Zhang Man Xu Dong-Mei Wu Jia-Hong Chen 《Chemical Engineering Communications》2013,200(4):545-556
Gallic acid and ellagic acid have been identified in the seed of Cornus officinalis by the use of an ultrahigh performance liquid chromatography (UHPLC) method coupled with a diode array detector (DAD). The water extract of C. officinalis seed contained the highest gallic acid content (3.03 ± 0.10 mg/g seed), which was followed by aqueous methanol extract (2.43 ± 0.10 mg/g seed) and aqueous ethanol extract (1.53 ± 0.25 mg/g seed). But a higher concentration (12.32 ± 0.45 mg/g seed) of ellagic acid was obtained from extraction with aqueous methanol than with aqueous ethanol (11.03 ± 0.42 mg/g seed) and water (7.28 ± 0.16 mg/g seed). After heat treatment and acid hydrolysis, C. officinalis seed had higher concentrations of gallic acid and ellagic acid, contributing to more potent antioxidant activity. The results demonstrated a rich source of gallic acid and ellagic acid in C. officinalis seed, which might provide a novel source of these natural antioxidants. 相似文献
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A comparison between catalytic ozonation and activated carbon adsorption/ozone-regeneration processes for wastewater treatment 总被引:1,自引:0,他引:1
P.M. Alvrez F.J. Beltrn F.J. Masa J.P. Pocostales 《Applied catalysis. B, Environmental》2009,92(3-4):393-400
Two methods based on the use of granular activated carbon (GAC) and ozone to remove organic compounds from water have been investigated. Both methods have been applied to degrade an aqueous solution of gallic acid and a secondary effluent from a wastewater treatment plant (WWTP). One of the methods, namely catalytic ozonation, implies simultaneous ozonation and adsorption onto GAC. This process takes advantage of the oxidizing power of ozone and the adsorption capacity of GAC but also of the catalytic transformation of ozone into secondary oxidants on the GAC surface. The efficiency of catalytic ozonation was compared to those of single adsorption and single ozonation. It was found that the catalytic process highly improves the conversion of total organic carbon (TOC) and makes a more efficient use of ozone than the single ozonation process. To illustrate the reusability of the catalyst, the GAC was reused four times through a series of consecutive experiments. No loss of catalytic activity was observed when treating the WWTP effluent but some deactivation could be appreciated when treating the aqueous solution of gallic acid. This deactivation could be attributed to some porosity destruction and surface oxidation produced as a result of reactions of aqueous ozone on the GAC surface. The other method investigated is an adsorption-regeneration process (namely GAC/O3-regeneration) that comprises two steps: dynamic adsorption onto GAC and further regeneration of the spent GAC with gaseous ozone. The adsorption stage of the GAC/O3-regeneration experiments was carried out in a continuous flow adsorption column and breakthrough curves were obtained. It was observed that the GAC used in this work adsorbed gallic acid very efficiently but exhibited limited capacity to remove chemical oxygen demand (COD) from the WWTP effluent. The optimum ozone dose to regenerate the spent GAC after gallic acid adsorption was found to be about 0.4 g O3/g GAC, with results showing around 90% regeneration efficiency. As a result of incomplete regeneration, the GAC adsorption capacity progressively decreased with the number of adsorption–regeneration cycles. The GAC/O3-regeneration method was not successful at treating the WWTP effluent as low adsorption uptake was observed. Moreover, the GAC became damaged after regeneration because of excessive oxidation of its surface. 相似文献