提取6-姜酚分子印迹聚合物的制备及应用

为从生姜中提取高纯度的6-姜酚,用姜酮代替6-姜酚作为模拟模板,以甲基丙烯酸为功能单体(MAA),二甲基丙烯酸乙二醇酯(EGDMA)为交联剂,偶氮二异丁睛(AIBN)为引发剂,乙醚为致孔剂,用单甘酯作为乳化剂,在含水乳状液状态下,合成球形的姜酮-分子印迹聚合物。将脱除模板的分子印迹聚合物(MIPs)装柱,然后上新鲜姜汁,吸附达到平衡后,用清水洗脱除去杂质,再分别用体积分数10%、15%、20%、25%、30%、35%、40%、95%食用酒精依次洗脱被吸附的姜酚。收集的洗脱液分别经真空浓缩,萃取后得到的残留物用高效液相色谱(HPLC)测定其6-姜酚含量。结果显示20%、25%的洗脱液中6-姜酚含量最高,两者共占所获6-姜酚总量的79.07%,其中MIPs对6-姜酚的吸附能力为63.35mg/g,远远大于空白印记聚合物(NIPs)对6-姜酚的吸附能力11.26mg/g,因此合成的MIPs对6-姜酚具有高度的特定选择性,可以用于工业化生产制备6-姜酚。     

白藜芦醇分子印迹聚合物的应用及性能研究

采用分子印迹技术以白黎芦醇为模板分子,选择丙烯酰胺作为白藜芦醇印迹聚合物的功能单体,氯仿和四氢呋喃的混合溶液作为印迹聚合物合成溶剂,制备了白黎芦醇分子印迹聚合物,考察了分子印迹聚合物的吸附性能、选择性能以及固相萃取性能。优化分子印迹固相萃取的萃取条件,选择30%(体积分数)的乙醇-水溶液5 m L作为上样溶液,选择40%(体积分数)的乙醇-水溶液作为淋洗液、80%(体积分数)的乙醇-水溶液作为洗脱液。     

间苯氧基苯甲醛表面分子印迹聚合物的制备和应用

采用分子印迹技术,以间苯氧基苯甲醛为模板分子,纳米Si O2为载体,氨基硅烷(3-Aminopropyl triethoxy silane,APTES)为功能单体,四乙氧基硅烷(tetraethyl orthosilicate,TEOS)为交联剂,通过溶胶-凝胶法制备得到表面印迹聚合物(molecularly imprinting polymers,MIPs),并通过红外光谱和扫描电镜对其进行表征。以高锰酸钾为显色指示剂结合分子印迹聚合物,建立了检测间苯氧基苯甲醛的新方法,并优化了检测方法的条件。结果表明,印迹聚合物的饱和吸附量约是非印迹聚合物(non-imprinted polymers,NIPs)的2.5倍。在搅拌吸附时间为10min时,可达到最大吸附量;超声洗脱时间为10min时,即可洗脱完全,实验结果表明该印迹聚合物对间苯氧基苯甲醛具有较好的选择性,检测限可达到0.9μg/m L。该方法在江水中进行加标回收实验的回收率在82.7-92.8%。     

桔霉素分子印迹预组装体系的量子化学模拟及吸附性能研究

为解决桔霉素分子印迹聚合物在构建和应用过程中模板分子泄露和功能单体筛选工作量大的问题，以1-羟基-2-萘甲酸为假模板分子，基于液相色谱法构建桔霉素和1-羟基-2-萘甲酸的同时检测方法，该方法对分子印迹洗脱液中的两种目标物具有良好的回收率(≥95%)，也能对功能红曲醇提液中桔霉素进行分离。运用量子化学方法，通过分子构型优化、原子电荷分布计算和结合能计算优选了构建分子印迹聚合物的功能单体2，6-二氨基吡啶。以响应面对其制备工艺进行优化，优化后的聚合物对桔霉素的吸附载量为(195.10±13.21)ng/g，相比优化前提高了0.79倍。以甲基丙烯酸为功能单体构建的桔霉素分子印迹聚合物为对照，对比了优化后的聚合物和对照聚合物的吸附性能，前者对桔霉素的吸附载量为后者的3倍，证实计算机模拟技术在桔霉素分子印迹聚合物构建中的实用性，旨在为分子印迹聚合物的构建和桔霉素富集与检测提供参考。     

利用分子印迹技术分离植物中的生物碱

分子印迹技术是制备具有分子识别能力聚合物的技术.它在印迹分子存在的情况下功能性单体与交联剂共聚制得高交联的聚合物网络,移去印迹分子后就得到了对印迹分子具有分子记忆效应的分子印迹聚合物.作为一种新型的分离介质,在分离、环境分析和催化科学等领域中极具发展潜力.本实验研究了模板分子、功能单体、交联剂、溶剂等对印迹聚合物制备的影响.并对聚合物方法的优势进行了较为详细的讨论.通过紫外光度法研究了模板分子(CF)与功能单体(AA)的相互作用,预测聚合物的选择性和结合机理.     

双模板大豆异黄酮类特异性分子印迹聚合物微球的制备及性能研究

为探寻大豆异黄酮类物质的富集分离的新方法和新思路,选用染料木苷和大豆苷含量总和为89.2%的大豆异黄酮为模板,采用沉淀聚合法,以4-乙烯基吡啶（4-VP）为功能单体,乙二醇二甲基丙烯酸酯（EGDMA）为交联剂,偶氮二异丁腈（AIBN）为引发剂,成功制备了分子印迹聚合物微球,并对微球进行了吸附静态学、吸附动力学、类特异选择性和结构表征研究。通过紫外光谱法研究了模板分子与功能单体的相互作用,结果显示4-VP和模板分子作用强烈,模板分子和4-VP最佳摩尔质量比为1:6。静态吸附实验表明印迹聚合物（MIP）与非印迹聚合物（NIP）相比,MIP对模板分子具有明显的特异性吸附。吸附动力学实验表明聚合物微球在5h内对模板分子达到饱和吸附。类特异选择性实验表明MIP对多种大豆异黄酮类单体组分具有明显的类特异性吸附,特异吸附量高。此印迹聚合物微球有望在大豆苷异黄酮富集、分离、检测方面得到广泛的研究和应用。      

食品中核-壳型罗丹明6G磁性分子印迹固相萃取材料的制备及应用

结合磁性分离技术和表面分子印迹技术,以改性Fe3O4为核、罗丹明6G分子印迹聚合物膜为壳,制备核-壳型磁性分子印迹聚合物微纳米材料。研究其对罗丹明6G的吸附性能,探讨了吸附动力学、吸附等温线及分子识别性,并将它应用于食品中分离富集罗丹明6G。结果表明：所制备的核-壳型磁性分子印迹聚合物具有高吸附容量（表观最大吸附量达24.69 mg/g）、快速的结合动力学（20 min达吸附平衡）及显著的吸附选择性（印迹因子达4.20）。以其作为新型固相萃取材料,结合高效液相色谱检测,对加标食品样品中的罗丹明6G进行分离、纯化、检测,加标回收率为92.3%～99.2%;相对标准偏差为0.85%～1.12%;检出限为0.003 8 μg/mL。在外加磁场作用下分子印迹聚合物可快速与样品基质分离,提高了实验效率。本方法简单快速,可应用于食品中非法添加的罗丹明6G的分离检测。     

混合三模板分子印迹固相萃取柱应用于粮谷中三唑类农药的检测

建立了采用混合三模板分子印迹固相萃取-高效液相色谱法分离检测粮谷样品中3种三唑类杀菌剂残留的方法。以联苯三唑醇、腈菌唑、烯唑醇为混合模板分子,采用本体聚合法合成了具有高选择性的混合三模板分子印迹聚合物,以该聚合物为填料制备混合三模板分子印迹固相萃取柱,并结合高效液相色谱法检测粮谷中联苯三唑醇、腈菌唑、烯唑醇残留。结果表明,以20 mL水为淋洗剂,15 mL甲醇为洗脱剂,并在最佳色谱条件下,联苯三唑醇、腈菌唑、烯唑醇的平均回收率分别为74.0%~82.4%、79.0%~86.2%、77.5%~85.1%,相对标准偏差(RSD)≤4.4%,该混合三模板分子印迹聚合物对3种杀菌剂具有特异性吸附能力,该分析方法可用于样品中三唑类杀菌剂残留的分离检测。     

分子印迹固相萃取技术对六堡茶中表儿茶素的分离特性

以表儿茶素为模板分子,丙烯酰胺为功能单体,偶氮二异丁腈作为引发剂,乙二醇二甲基丙烯酸酯为交联剂,通过原位聚合法制备分子印迹聚合物。首先考察不同模板分子、功能单体、交联剂比例条件下表儿茶素分子印迹聚合物的特异性吸附能力。结果表明表儿茶素与丙烯酰胺、乙二醇二甲基丙烯酸酯物质的量比为1∶6∶40时,分子印迹聚合物的吸附效果最佳,其模板分子回收率KMIPs为84.62%,特异性识别因子Q为4.55;然后利用扫描电子显微镜和红外光谱技术对制备的印迹聚合材料进行表征;最后在毛细管电泳最优条件下对加载过固相萃取柱的过柱液与洗脱液进行检测,建立分子印迹固相萃取-毛细管电泳联用检测表儿茶素的方法。实验结果表明,分子印迹聚合物成功聚合,形貌良好且具有专一吸附特性。该方法适用于六堡茶中表儿茶素的检测。     

氨基甲酸乙酯分子印迹聚合物的制备表征及分子识别性能研究

采用分子印迹技术,以β-环糊精衍生物为功能单体,氨基甲酸乙酯(EC)为模板分子,合成了对氨基甲酸乙酯有特异性识别和吸附的新型分子印迹聚合物(MIP)。通过红外光谱(IR)、核磁共振(13C-NMR)、扫描电镜(SEM)对其结构进行表征,利用气-质联用仪(GC-MS)测定该分子印迹聚合物对EC的选择性识别性能,构建Scatchard模型理论方程。结果表明,设计的反应合成路线合理,成功制备出新型EC分子印迹聚合物。合成的氨基甲酸乙酯分子印迹聚合物,通过共价键联分子作用对EC产生分子识别作用,表现出优异的选择性吸附功效。构建的理论方程定量解析出该分子印迹聚合物对模板分子有两类识别位点,动态理论方程体现出其优异的吸附特性。有关结果可为无特异性结构的氨基甲酸酯类污染物的去除和分离提供技术参考。     

Storage Stability of a Processed Ginger Paste

A processed paste was prepared from fresh ginger so that a convenient, shelf-stable product with the odor characteristics of fresh ginger could be manufactured from ginger produced in excess of fresh market demand. The paste was sampled periodically for color by Hunter YI index, odor by trained panel and (6)-gingerol (the major pungent component) by HPLC. This product was found to have a fair shelf-life under refrigeration, but degradation of color, odor and (6)-gingerol made the paste unacceptable after 8 wk storage at 25°C or 37°C.     

文冬姜化学成分研究

为研究文冬姜的营养价值,本文采用国标方法测定文冬姜中的基本营养成分。用超临界二氧化碳萃取法提取文冬姜和罗平小黄姜的姜油树脂,采用气相色谱-质谱法测定挥发性成分,高效液相色谱法测定姜酚类物质含量。结果表明,与中国食物成分表中罗平小黄姜的营养成分相比,文冬姜中含有较高的脂肪、膳食纤维和铁、锌、硒等微量元素。文冬姜姜油树脂中主要挥发性成分为α-姜烯(17.47%)、β-柏木萜烯(9.68%)和α-法呢烯(7.49%),6-姜酚、8-姜酚和10-姜酚的含量分别为338.08、57.07和84.87 mg/g。文冬姜和罗平小黄姜姜油树脂中的主要挥发性成分均为萜烯类化合物,但文冬姜中6-姜酚、8-姜酚和10-姜酚的含量分别为罗平小黄姜的2.8、1.8、1.0倍。     

6-姜酚对幽门螺杆菌的抑菌作用研究

探讨生姜中姜辣素的主要成分6-姜酚体外抗HP(Helicobacter pylori,HP)的作用。分别采用95%乙醇和自来水提取生姜中抗HP的成分,以阿莫西林为阳性对照,以溶剂50%PEG400和无菌水为空白对照,体外法测定生姜提取物和标准品6-姜酚对HP的抑菌作用的最小抑菌浓度(MIC)。生姜醇提物对HP的MIC为1.00 mg/mL,6-姜酚的MIC为0.02 mg/mL,生姜水提物对HP在体外无抑菌作用。6-姜酚是生姜对HP的抑菌作用的主要活性成分之一。     

Characterisation of cultivars of Jamaican ginger (Zingiber officinale Roscoe) by HPTLC and HPLC

In this study, a novel high performance thin layer chromatography (HPTLC) technique for fingerprinting of Jamaican ginger was developed and its application to the chemo-profiling of four cultivars of Jamaican ginger illustrated. Applications of the method to maturation and storage studies involving ginger oleoresins are also presented. The method showed good resolution of the pungent compounds characteristic of ginger: 6-gingerol, 8-gingerol, 10-gingerol and 6-shogaol, with five other discrete zones being described as additional references. HPTLC fingerprints of the ginger cultivars showed chemical homogeneity with small qualitatively observed differences in the intensities of the gingerol and shogaol zones. Quantification of these compounds by high-performance liquid chromatography (HPLC) revealed significant differences in total pungency among the cultivars. Essential oil yields from the cultivars also varied significantly. The described characterisations will prove useful in the authentication of Jamaican ginger.     

Extraction of ginger rhizome: kinetic studies with dichloromethane, ethanol, 2-propanol and an acetone—water mixture

The kinetics of extraction of [6]-gingerol from ground Jamaican ginger rhizome have been determined at 30°C in dichloromethane, ethanol, isopropanol and an 80% (v/v) acetone + 20% (v/v) water mixture. The extractions all proceeded in three stages: an initial 'washing' stage, a fast stage and a subsequent much slower stage. The rate of extraction of hexahydrocurcumin in ethanol was found to follow a simpler pattern. From the first order plots, the diffusion coefficients of the extracted solubles within the ginger particles were calculated. They varied inversely with the 0.6 power of the solvent viscosity, which explained why the rates of [6]-gingerol extraction decreased in the sequence: acetone < acetone + water < dichloromethane < ethanol < isopropanol. These results show that solvents of low viscosity should be chosen to attain fast extraction rates. The diffusion coefficient of [6]-gingerol was also measured at 30°C in pure acetone, ethanol and isopropanol. The values in these bulk solvents were 13–20 times greater than the diffusion coefficients of [6]-gingerol within the ginger particles for the fast stage and over 900–1800 times greater than those for the slow stage. These hindrance factors quantify the effect of the ginger matrix environment on internal diffusion.     

Extraction of ginger rhizome: partition constants and other equilibrium properties in organic solvents and in supercritical carbon dioxide

Equations have been derived for the direct and indirect methods of determining partition constants for constituents extracted from food and other natural materials. A careful distinction is drawn between mass and volume partition constants. The direct method has been applied to the extraction of [6]-gingerol from Jamaican ginger rhizome with supercritical carbon dioxide and the indirect method to its extraction with acetone, dichloromethane, ethanol and isopropanol. The resulting average mass partition constants were 0.2₉ and 0.3₉, respectively. The content of [6]-gingerol in the original ginger rhizome was found to be 31–32μmol g⁻¹. The extent of oleoresin extraction from the ground ginger and the degree of swelling and organic solvent uptake were also measured.     

生姜和辣椒及其活性组分对卤煮牛肉中杂环胺生成的影响

为研究生姜、辣椒对卤煮牛肉中杂环胺含量的影响及其抑制机制,分别在卤煮牛肉中添加生姜和辣椒及其活性组分。结果表明:生姜和辣椒可以显著降低卤煮牛肉中杂环胺总量(P<0.05);利用液相色谱-串联质谱分离鉴定出生姜和辣椒中含量最高的活性组分为6-姜酚和辣椒素,分别添加2种活性组分均可以显著降低卤煮牛肉中杂环胺总量(P<0.05);通过自由基清除率分析,发现添加物质的抗氧化性强弱为6-姜酚>辣椒素>生姜>辣椒;相较对照组,分别添加6-姜酚和辣椒素均可以显著增加还原糖、肌酐、肌酸含量(P<0.05)。上述结果表明,生姜和辣椒可以有效抑制卤煮牛肉中杂环胺的形成,抑制效果与其所含活性组分的抗氧化性有关。     

Preparative separation and purification of gingerols from ginger (Zingiber officinale Roscoe) by high-speed counter-current chromatography

A novel method for purifying gingerols from ginger was developed using a high-speed counter-current chromatography (HSCCC). The two-phase solvent system such as light petroleum (bp 60–90 °C)–ethyl acetate–methanol–water (5:5:6.5:3.5, v/v/v/v) was applied to the separation and purification of 6-, 8- and 10-gingerol from a crude extract of ginger. The experiment yielded 30.2 mg of 6-gingerol, 40.5 mg of 8-gingerol, 50.5 mg of 10-gingerol from 200 mg of crude extract in one-step separation. And the purity of these compounds was 99.9%, 99.9% and 99.2%, respectively, as determined by high-performance liquid chromatography (HPLC). Their structures were identified by gas chromatography–mass spectrometry (GC/MS) and ¹H, ¹³C nuclear magnetic resonance (NMR).     

Extraction of ginger rhizome: kinetic studies with acetone

Ground sieved Jamaican ginger rhizome has been treated with acetone under various conditions and, in each case, the concentration of [6]-gingerol extracted was measured as a function of time. The results could be expressed by two intersecting first-order plots and an initial intercept, representing very rapid initial extraction, followed by a fast stage and a subsequent slow stage. At 30°C the rate constant of the slow stage was c. 95 times smaller than that of the fast stage and its activation energy was 3.6 times larger. The fast stage was not affected by solvent flow into the ginger particles, or by an increase in the stirring speed. These findings, together with the fact that both first-order rate constants were inversely proportional to the square of the radius of the particles, pointed to [6]-gingerol diffusion through the solid ginger as the rate-determining step. The data could also be fitted by the equation of So and MacDonald (1986). The relevance of the research to the industrial production of ginger oleoresin is pointed out.