吸附树脂提取分离银杏叶提取物的研究进展

银杏叶中含有具有药理作用的黄酮类化合物和银杏内酯类化合物,吸附树脂是提取分离银杏叶提取物（GBE）－银杏黄酮化合物和银杏内酯化合物的有效试,本文综述了树提取分离GBE的机理,比较了用不同树脂提取分离GBE的分离效果,并总结了影响吸附树脂分离提取GBE的多种因素,为树脂提取分离银杏黄酮提供了较为全面的科学信息。     

银杏叶中4种活性成分含量分布规律研究

采用HPLC法对不同树龄及不同年生长月份银杏叶中总黄酮、总萜内酯、莽草酸、绿原酸4种成分含量进行检测,发现树龄对银杏叶中绿原酸、总黄酮、总萜内酯含量有影响,莽草酸含量受树龄影响较小。不同树龄中,1～10年银杏叶中总黄酮、总萜内酯均达到药典要求,而上100年的银杏叶中总萜内酯含量低于0.25%,质量达不到药典要求。4月至9月银杏叶中总黄酮、绿原酸含量随采摘月份增加而下降,而总萜内酯则随叶子年生长月份变大而升高,含量8～9月达到最高,莽草酸含量随月份变化影响较小。研究了不同树龄及不同年生长月份对银杏叶中总黄酮、总萜内酯、莽草酸和绿原酸4种活性成分含量的影响规律,为银杏叶中4种活性成分进行综合利用提供了参考数据。     

甲醇-水流动相HPLC测定银杏萜内酯方法优化

优化了甲醇-水流动相HPLC测定银杏萜内酯的方法,建立了线性回归方程,并与药典正丙醇-四氢呋喃-水流动相方法进行比较。在此基础上,用两种方法对银杏叶、银杏外种皮、白果以及银杏叶提取物(EGB)样品中的萜内酯含量进行了对照分析。结果表明,甲醇-水梯度洗脱基线噪音小,柱效高,分离时间短。优化的洗脱条件为:甲醇-水为流动相,0～2 min,0～20%甲醇; 2～32 min,20%～60%甲醇,建立的方法在50～2 000 mg/L的浓度范围内具有良好的线性关系,检出限为0. 05～0. 09μg,不同浓度水平的加标回收率为92. 4%～101. 6%,相对标准偏差(RSD)值为2. 7%～5. 1%。两种方法测定银杏萜内酯没有明显差别,其中测定银杏叶中白果内酯、银杏内酯C、银杏内酯A、银杏内酯B的相对误差分别为0. 86、4. 2、1. 7、3. 9。     

茶多酚的提取及在医药方面应用

茶多酚，英文名Tea Ployphenols，简称TP。茶多酚是茶叶中三十几种酚类物质的总称，按照其化学结构可分为4类：儿茶类、黄酮及黄酮醇类、花白素及花青素、酚酸和缩酚酸类。其中活性物质儿茶类约占多酚总量的80％，主要有4种：表儿茶素（EG）、表儿茶素没食子酸酯（ECG）、表没食子儿茶素（EGC）、表没食子儿茶素没食子酸酯（EGCG），其中EGCG具有很强的抗氧化活性和清除自由基能力。     

白果外种皮中银杏酚酸提纯及其抑菌活性初探

从白果外种皮中提取纯化银杏酚酸，并对其抑菌作用进行初步研究。采用正交实验筛选加热回流提取条件，有机溶剂萃取结合柱层析方法分离纯化银杏酚酸，生长速率法测定银杏酚酸对植物病原真菌菌丝抑制率。加热回流提取参数：提取溶剂为甲醇，40℃，料液比为1∶12,90 min；经乙酸乙酯萃取、脱酸树脂柱层析纯化，获得80.96%含量银杏酚酸；对5种植物病原真菌均有抑制作用，含量为0.293 mg/m L时对月季炭疽病菌（Colletotrichum boninense）抑制率为49.09%、对杜鹃炭疽病菌（C.fioriniae）为30.30%、对石榴干腐病菌（Coniella granati）为23.26%、对葡萄炭病疽菌（C. gloeosporioides）为21.70%和对烟草枯萎病菌（Fusarium redolens）为21.01%。结果表明，提纯工艺把白果外种皮中8%银杏酚酸提高至80.96%，确定银杏酚酸可较好抑制月季炭疽病菌菌丝生长。     

溶剂极性对沙棘渣提取物组成及体外降血糖、降血脂活性的影响

为探讨溶剂极性对沙棘渣提取物组成及体外降糖降脂活性影响，以沙棘果渣和籽渣为原料，采用不同极性溶剂经超声波辅助提取，评价沙棘渣中活性成分含量及其体外降血糖和降血脂能力，结合超高效液相色谱串联四极杆静电场轨道阱高分辨质谱(UPLC-Q-Orbitrap HRMS)对沙棘渣中活性成分进行鉴定。结果表明，溶剂极性对多酚类化合物的提取效率、降血糖、降血脂能力有显著影响，其中60%乙醇提取物具有最高的粗提物得率，果渣的60%乙醇提取物中总酚含量（11.08 mg/g）、总黄酮含量（6.49 mg/g）和原花青素含量（6.18 mg/g）最高。籽渣的80%乙醇提取物中总酚含量（25.70 mg/g）最高，丙酮提取物中总黄酮含量（14.23 mg/g）、原花青素含量（16.87 mg/g）最高。沙棘果渣和籽渣丙酮提取物具有最好的α-葡萄糖苷酶与α-淀粉酶活性抑制能力。籽渣80%乙醇提取物、果渣60%乙醇提取物具有最好的甘氨胆酸钠和牛磺胆酸钠结合能力。原花青素是籽渣提取物体外降血脂、降血糖活性主要贡献者。果渣提取物中的总多酚与降血脂能力显著相关。从沙棘渣提取物中共鉴定出37种化合物，主要为黄酮和萜类成分。沙棘籽渣提取物具有很强的体外降血糖、降血脂活性，有望用于特膳食品和功能性食品基料的研发。     

从银杏叶中提取银杏黄酮的最佳工艺条件研究

对用９０％乙醇从银杏叶提取银杏黄酮的工艺进行了研究，得到最佳工艺条件为：采用５次水沉降除杂；在ｐＨ３～４条件下吸附；对吸附过树脂采用树脂重量的１３倍水洗和７倍２５％乙醇洗；树脂每吸附过３次再生１次；洗脱液经喷雾干燥得产品。在此最佳工艺条件下得到的银杏黄酮，黄酮含量大于２６％，内酯含量大于６％。     

原花青素的层析分离及清除自由基的活性研究

对葡萄籽中提取的原花青素进行层析分离,考察其清除自由基的活性。用AB-8大孔吸附树脂对葡萄籽原花青素粗提物进行分级分离,采用不同浓度甲醇液进行洗脱,经高效液相色谱检测洗脱液中组分含量,测定洗脱液对邻苯三酚超氧自由基O2-·的清除作用。40%和60%甲醇洗脱液具有很强的清除O2-·自由基的能力,两种洗脱液抑制邻苯三酚自氧化率分别达65 2%和82%。原花青素是一种天然有效的自由基清除剂。     

超声波辅助醇提法提取银杏叶中多种活性成分

采用超声波辅助醇提法综合提取银杏叶中多种活性成分,通过溶剂萃取法脱脂、去叶绿素,经DM130大孔树脂吸附脱附后,再对银杏多糖、银杏莽草酸、银杏黄酮分阶段逐一分离纯化,并对工艺条件进行了优化。结果表明,在75%乙醇为提取溶剂、超声时间为2.0 h、石油醚为脱脂溶剂的最佳条件下,分别采用0.2%H₂O₂脱色法、石油醚沉淀法、酸碱除杂法对银杏多糖、银杏莽草酸、银杏黄酮进行分离纯化,得到高纯度银杏多糖、银杏莽草酸、银杏黄酮,其纯度分别为85.20%、98.25%、35.72%,产率分别为4.67%、3.80%、0.77%。该方法工艺简单、成本低、资源利用度高,为银杏叶的综合开发利用提供了参考。     

大孔树脂吸附纯化葡萄籽原花青素的研究

采用大孔树脂对葡萄籽原花青素进行吸附纯化,以吸附率和解吸率及纯化效果为指标,比较了7种大孔树脂对原花青素的吸附解吸性能。研究了上样量、洗脱剂浓度、上样流速、洗脱剂用量对原花青素纯化效果的影响。结果表明,AB-8大孔树脂对葡萄籽中原花青素的吸附效果最好,树脂体积为20 mL,上样量为80 mL,上样流速为40 mL/h,用40%的乙醇洗脱,洗脱剂用量为100 mL,洗脱流速为80 mL/h时的纯化效果最好,该条件下原花青素洗脱率为94.37%,所得溶质纯度可达89.63%。     

Preparation and metal ion adsorption properties of the resin containing sulfonic acid groups

In this study, we explored a new ion exchange material synthesized by radical polymerization of styrene and 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid by using 2,2′‐azo‐isobutyronitrile (1 mol %) and divinylbenzene (0.5 mol %) as initiator and crosslinking reagents, respectively. The resin was obtained from a large excess (90%) of styrene in the feed. The yield was 72.3%. The resin was completely insoluble in water and characterized by elemental analysis, FTIR spectroscopy, scanning electron microscopy, and thermal analysis. The metal ion retention capability was investigated for Ag(I), Hg(II), Cd(II), Zn(II), Pb(II), and Cr(III). The effect of pH, time, and resin/metal ion mol ratio on the metal ion retention was studied. Selectivity of the resins from a mixture of metal ions and the maximum retention capacity at optimum pH were also determined. The recovery of the resin by using 1 and 4 M HClO₄ and HNO₃ demonstrated that it is possible to recover the resin above 80%. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1230–1235, 2003     

MIEX和PAC对微污染水源水的水质净化效果比较

研究了MIEX和PAC两种水处理吸附剂对微污染水源水的水质净化性能。实验分别考察了MIEX和PAC对DOC和UV₂₅₄的去除效率,并通过凝胶渗透色谱和三维荧光光谱分析,研究了MIEX和PAC对不同相对分子质量区间以及不同种类有机物的去除规律。在正常的吸附剂投加量下(MIEX 5~8 ml·L^-1,PAC 30~50 mg·L^-1),MIEX对DOC和UV₂₅₄的平均去除率比PAC高23%和20%。但随着吸附剂投加量的增加,两者去除效率差别逐渐减小,MIEX对DOC和UV₂₅₄的最大去除率仅比PAC高6%~8%。与PAC相比,MIEX去除的有机物相对分子质量分布范围更广,特别是对中等分子量(5000~50000)有机物,其去效率明显高于PAC。MIEX对腐殖酸和富里酸类有机物的去除率略高于PAC,而对蛋白质类有机物的去除率则远高于PAC。动力学分析表明,MIEX和PAC对DOC的吸附去除过程符合准二级动力学,MIEX对有机物的吸附速率是PAC的40倍左右。     

大孔吸附树脂精制鱼腥草黄酮类化合物

Flavonoids are one main kind of effective components in Houttuynia cordata Thunb., which display a wide range of pharmacological activity. In this study supercritical fluid extraction （SFE） with carbon dioxide was first used as preparat ion step to remove the volatile components, which are also active components, from Hout-tuynia cordata Thunb. Then ultrasound-assisted extraction was used to obtain the crude flavonoids and the macro-porous resin adsorption technology was further employed to purify the flavonoids. Nine kinds of macroporous resins with different properties were tested through static adsorption, and one macroporous resin labeled as D101 was selected. The effect of several factors, such as the ratio of column height to diameter, initial concentration and pH, on both flavonoids yield and content were explored by dynamic adsorption to obtain reasonable conditions of adsorption and desorption. The experimental results show that the content of fiavonoids can be above 60% with fia- vonoids recovery of 93.3 % under the optimum conditions of purification. HPLC analysis of the final flavonoids product shows it contains quercitrin, hypefin, rutin and quercetin.     

Thermoseparating Aqueous Two-Phase System for the Separation of Alkaline Proteases from Fish Viscera

The objective of this study was to isolate alkaline proteases from farmed giant catfish viscera by using a thermoseparating aqueous two-phase system (T-ATPS). Different phase partitioning parameters—type of salts, NaCl addition, and temperature—were optimized. The optimum system contained 40% EOPO3900-10% MgSO₄ with 17%NaCl, induced phase separation at 55°C, and provided the highest recovery (77.98 %) and purity (PF: 21.50-fold) with a partition coefficient (K_E) of 11.90 and a volume ratio (V_R) of 0.19. In the recycling step, the mixture of the bottom salt-rich phase and bottom EOPO-rich phase in the ratio of 0.5:1.5 (w/w) provided the highest recovery and purity. Hence, the total recovery of 91.62% was obtained from the separation system. Three major clear zones (24, 36, and 130 kDa) can be distinctively observed on casein-substrate gel electrophoresis for protease activity staining. Major protein components of perilla seed hydrolysates were completely hydrolyzed by the alkaline proteases at 70 units while those of red kidney bean isolate were more resistant to protein hydrolysis. Fifty units of Flavourzyme® hydrolyzed completely both plant proteins into small peptides or amino acids. As a result, T-ATPS could be used as an alternative method for the separation of enzymes from various sources with acceptable recovery. In addition, the obtained alkaline proteases can be further used in preparation of protein hydrolysates.     

Optimization of Cellulase Production from Isolated Cellulolytic Bacterium: Comparison between Genetic Algorithms,Simulated Annealing,and Response Surface Methodology

The present study discusses optimization of cellulase production from isolated cellulolytic bacterium. A simulated annealing (SA) algorithm is proposed for optimization of these processes to achieve the desired production goal. The approach was compared to the use of evolutionary algorithms, i.e., genetic algorithms (GAs) and response surface methodology (RSM). Ochrobactrum haematophilum was identified as the isolated bacteria. Carboxymethyl cellulose (CMC) concentration, yeast extract, pH, and incubation temperature were the significant factors screened by Plackett–Burman design and further optimized using a central composite design. The optimum values obtained were CMC concentration = 4.76% (w/v), yeast extract = 2.03% (w/v), pH = 6.3, and temperature = 44.2°C. Carboxy methyl cellulase (CMCase) activity at these values was experimentally determined to be 3.55 ± 0.16 U/ml, which was 2.8 times than the unoptimized system (1.23 U/ml). The growth-associated and non-growth-associated Leudeking–Piret constants, α and β, were respectively determined to be 0.3943 and 0.0105. The Michaelis–Menten constants, V_max and K_m, were determined to be 0.67 µmol/min and 2.42 mg CMC/ml, respectively. The variable-sized SA seems to be the best alternative, outperforming the GAs, showing a fast convergence and low variability among the several runs for optimized production cellulose recovery. The SA models are found to be capable of better predictions of cellulase production. The results of the SA-based RSM model indicate that it is much more robust and accurate in estimating the values of dependent variables when compared with the GA-based RSM models and only RSM models.     

大孔树脂分离纯化核桃青皮总黄酮的研究

以总黄酮回收率为考察指标,研究了大孔树脂分离纯化核桃青皮总黄酮的工艺。结果表明:D101型树脂对核桃青皮总黄酮有较好的吸附分离性能,是分离纯化核桃青皮总黄酮的适宜大孔树脂;最佳工艺条件为:上柱总黄酮与干树脂质量比为1:12,上样液质量浓度可在3.0875～6.175 g/L 范围内,pH值为5, 6BV(1BV=23.7 mL)的水洗后用5BV的70%乙醇洗脱。经D101处理后的核桃青皮总黄酮回收率在60%,纯度可达80%以上。该工艺简便,能有效分离纯化核桃青皮黄酮类化合物。     

电热双敏型形状记忆石墨烯/聚氨酯/环氧树脂复合材料的制备及其性能

以自制聚氨酯预聚体与环氧树脂复合形成互穿聚合物网络结构,采用共混方法添加自制高导电性石墨烯,制备了电热双敏型形状记忆复合材料,研究了其性能. 结果表明,以20%(w)聚氨酯/环氧树脂为基体所制1.0%(w)石墨烯/聚氨酯/环氧树脂复合材料的分散性良好,玻璃化转变温度稍低于纯环氧树脂,拉伸强度是纯环氧树脂的93%,导电性达3.58′10-4 S/m,固定率为95.5%,回复率为97.5%,循环5次后固定率不低于95%.     

Aqueous Two-Phase Extraction of Lactic Acid: Optimization by Response Surface Methodology

In this study a suitable alcohol/salt aqueous two-phase (ATP) system was selected for the recovery of lactic acid from an aqueous solution. From the different ATP systems studied, the ethanol/dipotassium hydrogen phosphate ATP system appeared to be favorable. To examine the potential of this ATP system, the extraction yield of lactic acid in aqueous solutions was optimized with the response surface methodology. The parameters studied were concentrations of ethanol (22.00–38.80%, w/w), dipotassium hydrogen phosphate (15.00–31.80%, w/w) and lactic acid (26.36–93.64 g/L). The optimum conditions were found to be 30.23% w/w ethanol, 18.40% w/w dipotassium hydrogen phosphate, and 80 g/L lactic acid. Under these conditions, a favorable extraction yield of lactic acid was obtained. The maximum partition coefficient of lactic acid and extraction yield was determined as 2.26 and 87%, respectively. The optimum extraction conditions were then used to guide the recovery of lactic acid from a real fermentation broth. As a result, the partition coefficient and extraction yield of lactic acid reached 2.06–80%, respectively.     

超声-微波协同萃取法提取昆仑雪菊中总黄酮的研究

采用超声-微波协同萃取法,从新疆昆仑雪菊中提取黄酮并以芦丁为标准品,用分光光度法测定了其中总黄酮的含量。芦丁浓度与吸光度的线性关系方程为：A=0.01109C＋0.01012（r=0.9997）,表明芦丁在21.340～59.752μg/mL范围内线性关系良好,测得雪菊中总黄酮的含量为14.25%。该方法简便、可靠、准...     

MLA在广东斑岩型锡石矿嵌布特征及赋存状态研究中的应用

利用矿物自动分析系统(MLA)和X射线荧光光谱仪、原子吸收分光光度计等对广东某斑岩型锡矿小于2 mm的原矿进行工艺矿物学研究，考察矿物组成、嵌布粒度、连生及包裹关系。结果表明，锡石主要呈细粒浸染状嵌布于脉石矿物中，嵌布粒度细微，最大粒度约为0.250 mm，最小为0.001 mm，主要集中在0.020?0.090 mm之间，单体解离度仅为9.98%，连生体主要与石英、黄玉连生。约93%的锡石(硬度6.5)被石英(硬度7)、黄玉(硬度8)包裹或与之连生，属难磨难选矿石，原矿伴有少量钼、铋、钨、铜等有价元素。选矿原则流程可确定为优先浮选回收硫化矿(钼、铋、铜、钨)，窄级颗粒分别(或依次)重选回收锡石。