紫荆花红色素的提取及其稳定性研究

报道了从苏木科植物紫荆（CersischinensisBunge）的花中提取天然红色素的方法。对提取条件进行了优化实验，并在不同条件下考察了紫荆花红色素的稳定性。     

紫荆花与玫瑰茄微量元素含量的比较研究

首次报道紫荆花十种微量元素含量，并与玫瑰茄作了含量比较研究．     

红龙果食用红色素的提取及理化性质分析（I）

从红龙果中提取了食用红色素H和副产物，研究了该食用红色素的理化性质，包括红色素的溶解性和可见吸收光谱特征，溶液pH值、加热、光等对色素稳定性的影响；还进行了色素和副产物的IR分析，红龙果挥发油成分的GC-MS分析；研究表明该色素为水溶性色素，其吸收光谱因pH而异，在pH=4-7、低温、避光条件下稳定性好；副产物为肌醇。     

山楂红色素的研究

报道山楂红色素最稳定的ｐＨ值范围和受高温加热及强光照射时的变化，以及一些金属离子、有机酸、无机酸、糖类等食品中常见共存物质对山楂红色素稳定性的影响。     

天然红色素的提取研究进展

作为天然色素中的一大类,天然红色素在人们的日常生活中日益发挥着重要的作用。国内对天然红色素的提取研究起步较晚,但发展迅速。文章重点介绍了辣椒红色素、番茄红素、桑椹红色素等几种重要天然红色素的性质和提取方法,并比较了有机溶剂法、超临界CO2流体萃取法等提取方法的特点,同时对其效果和应用作了相应的展望。     

D61树脂吸附和分离萝卜红色素

本文研究了用Ｄ６１树脂吸附和分离萝卜红色素的方法，试验结果表明：Ｄ６１树脂吸附和分离萝卜红色素的交换容量为６０．９１ｍｇ／ｍｌ湿树脂，吸附平衡时间为４０分钟。被吸附的萝卜红色素用含０．１ｍｏｌＨＣｌ／ｌ的８０％乙醇洗脱，洗脱液温度为５０℃，流速为２ＢＶ／ｈｒ。Ｄ６１树脂非常稳定，使用１５次后交换容量仅降低１１％，再生１２次对其吸附能力无明显影响，萝卜苷是一种负离子，因而不被Ｄ６１树脂吸附。经过回上     

催化过氧化氢氧化杨梅红色素裉色光度法测定痕量锌

报道了杨梅红色素的提取与性质。基于加热条件下，Zn^2 催化过氧化氢氧化杨梅红色素灵敏的褪色反应，提出了测定痕量锌的新方法。所建立的方法对Zn^2 的线性范围为0．2－1．0μg/L，并成功地用于发样和奶粉中锌的测定。     

D-101树脂对胭脂虫红色素吸附特性的研究

绘制了胭脂虫红色素的标准曲线,从9种不同性质的大孔吸附树脂中筛选出D-101树脂用于分离胭脂虫红色素,研究了D-101树脂对胭脂虫红色素吸附动力学曲线和不同温度下的吸附等温线。实验结果表明:胭脂虫红色素溶液浓度与吸光度之间显示良好的线性关系;D-101树脂对胭脂虫红色素的吸附速率快,120min达到平衡,吸附量为143.17mg/g树脂,吸附动力学曲线符合二级吸附动力学模型;D-101树脂对胭脂虫红色素的吸附等温线符合Freundlich方程,低温有利于吸附;通过热力学计算得到H、G、S均小于0,说明吸附是放热过程且能自发进行,吸附后体系趋向有序。研究结果可为胭脂虫红色素的分离提供有益的参考。     

201×7树脂去除萝卜甙的研究

本文研究了用201×7树脂去除萝卜红色素提取液中萝卜甙的方法。试验结果表明：201×7树脂对萝卜甙的静态交换容量最大值可达到72．gmg／ml树脂，吸附平衡时间55分钟，最适pH值5．5。用5BV0．05molNaOH溶液可完全洗脱被交换在树脂上的萝卜甙，洗脱流速1．5BV／hr。去除萝卜甙的提取液真空浓缩，喷雾干燥得粉状萝卜红色素产品，E＝4．30。     

201×7树脂去除萝卡甙的研究

本文研究了用２０１×７树脂去除萝卜红色素提取液中萝卜甙的方法，试验结果表明：２０１×７树脂对萝卜甙的静态交换容量最大值可达到７２．９ｍｇ／ｍｌ树脂，吸附平衡时间５５分钟，最适ｐＨ值５．５。用５ＢＶ０．０５ｍｏｌ ＭａＯＨ溶液可完全洗脱被交换在树脂上的萝卜甙，洗脱流速１．５ＢＶ／ｈｒ，去除萝卜甙的提取液真空浓缩，喷雾干燥得粉状萝卜红色素产品，Ｅ１９０ １ｃｍ＝４．３０。     

Synthesis of Ammonium-Based Ionic Liquids for the Extraction Process of a Natural Pigment (Betanin)

The use of new synthesized ammonium-based ionic liquids was explored as an alternative to the current process implemented in the betanin extraction from red beet juice, resulting in high yields: 70% and 82%. Betanin is a vegetal pigment that has been applied to a large variety of products in the food industry, which is important, for it can work as a substitute for the red synthetic dyes used nowadays. Additionally, the use of the kosmotropic salt sodium acetate was explored in order to separate the complex formed by the ionic liquid and pigment of interest in a process that combined two techniques: ATPS (aqueous two-phase system) and SOES (salting-out extraction system). The results reveal that the studied techniques could work as a novel process for the extraction of betanin from red beet juice employing ionic liquids, which have not been tested for this purpose in other research.     

PHOTORECEPTOR PIGMENT IN Blepharisma: H+ RELEASE FROM RED PIGMENT

In faded cells of Blepharisma kept in a standard saline solution containing bacteria which had been cultured on agar plates containing glucose and polypepton, threshold light intensity for step-up photophobic response elevated. This result suggests that red pigment (blepharismin) contained in Blepharisma cells is involved in the step-up photophobic response. The pH of the aqueous solution of the red pigment was found to decrease when light was applied, indicating that the pigment releases H⁺ in response to light stimulation. However, faded pigment preparation by light irradiation did not show pH decrease. In the living cells faded by light irradiation, threshold light intensity for the step-up photophobic response was raised. Results suggest that H⁺ release from the red pigment induced by light irradiation might be responsible for the step-up photophobic response of the cells.     

Total Synthesis of Carthamin,a Traditional Natural Red Pigment

The first total synthesis of carthamin ( 3 ), a historic natural red pigment, has been achieved. The molecular structure was efficiently constructed by assembling two equivalents of the in situ generated lithiated monomers and triisopropyl orthoformate. This synthesis confirms the structure proposed in 1996.     

Total Synthesis of Carthamin,a Traditional Natural Red Pigment

The first total synthesis of carthamin ( 3 ), a historic natural red pigment, has been achieved. The molecular structure was efficiently constructed by assembling two equivalents of the in situ generated lithiated monomers and triisopropyl orthoformate. This synthesis confirms the structure proposed in 1996.     

Encapsulation of Hematite in Zircon by Microemulsion and Sol-Gel Methods

Microemulsion method has been applied and compared with sol-gel, coprecipitation and ceramic route with the purpose of encapsulating hematite into zircon crystals used as ceramic pigment. In the commercial synthesis of pink coral pigment, NaF flux agent is usually added in order to improve the reactivity of the system; therefore, the addition of flux agents (NaF or NaF · 2NaCl) has been investigated. Likewise, the effect of precipitating agent (NH₃ or NaOH) has been studied. Sol-gel becomes the more reactive method and produces the best red colours without fluorides addition, but does not give red colour in the presence of halides fired at 1000°C. Ammonia microemulsioned and coprecipitated powders give similar orange-brown colours without fluorides, and red colours with fluorides addition. The addition of NaF produces higher inclusion effectiveness than NaF · 2NaCl. The stabilization of sodium silicozirconate crystalline phases in NaOH coprecipitated or emulsioned samples avoids the zircon crystallization and then the hematite encapsulation.     

Anatase—a pigment in ancient artwork or a modern usurper?

Fragments of wall-paintings from Roman villas in Easton Maudit, which date from ca 150 AD have been studied by Raman spectroscopy. An intact ancient Roman paint pot discovered in the remains of a villa in Castor, Cambridgeshire, still containing a mixture of white and red pigment was also analysed and the pigments identified as haematite and anatase. The discovery of anatase in the intact artist’s paint pot, particularly, and also on fragments of broken paint pots from the Easton Maudit villa site, is a unique contribution to current knowledge of ancient European pigment history, because the presence of this mineral has not hitherto been recognised fully in an ancient artist’s palette. The relative spectral response of anatase and haematite in the Raman data is compared with that of anatase and other red pigments such as minium, cinnabar, and litharge.     

Color Tuning Mechanism of Human Red and Green Visual Pigments

We investigated the molecular mechanism of a rather large red shift of 31 nm in a human red pigment compared with a human green pigment. In this analysis, we paid special attention to the phenomenon of nonadditivity of spectral shifts due to substitution of the key amino acids (OH-bearing amino acids) and the phenomenon of cooperativity by which the spectral shifts due to substitution of the key amino acids in the protein environment of red pigment are about 1.5 times larger than that in the protein environment of green pigment. The analysis was made by using a model of three active sites on which the key amino acids are located and four effective sites by which the effect of the key amino acids is modified. As a result, we found that the interaction between the active sites that occurs through the repolarization of the chromophore induced by the key amino acid is essential for the nonadditivity phenomenon. We also found that the interaction between the active site and the effective site plays a major role in the cooperativity phenomenon. More directly, we say that the highly polarizable property of the chromophore is the origin of the rather large red shift in red pigment. Based on these analyses, we conclude that the interaction between the polarizable chromophore and the protein moiety has the capability of producing a significant spectral shift, at least 1000 cm-1, even by substitution of moderate polar residues of the OH-bearing amino acids.     

Preparation of Cr-Doped YAlO_3 Red Ceramic Pigment and the Coloration Mechanism

The red ceramic pigment is widely used in industrial production, but the pigments with pure color and bright red performance are rare. Therefore, it is important to study and develop new red ceramic pigment with perfect color performance. This paper reports the preparation of Cr-doped YAlO_3 red ceramic pigment rendering by sol-gel method with high temperature resistance, good color and proposed color mechanism. The prepared samples were characterized by XRD, SEM, EDS and UV-vis, and the effects of Cr on the crystal structure, color rendering properties and color mechanism were discussed. The results showed that the optimum concentration of coloring agent(Cr) in Cr:YAlO_3 red ceramic pigment was 3 at.%. The main color mechanism was also discussed. Compared with the solid phase sintering and precipitation methods for the synthesis of red ceramic pigment, the sol-gel method possessed obvious advantages, such as perfect mixing of the raw materials, uniform dispersion of doping ions and the pure color.     

高效液相色谱法考察不同炮制方法对知母中5种主要化学成分的影响

建立了高效液相色谱(HPLC)同时测定知母不同炮制品中新芒果苷、芒果苷、知母皂苷BIII、知母皂苷I和知母皂苷AIII含量的方法,探讨了不同炮制方法对知母化学成分的影响,为通过采用不同炮制方法来改变知母药性提供了依据。采用AlltimaTM C18色谱柱(250 mm×4.6 mm, 5 μm)分离,所用流动相为乙腈(A)和0.1%甲酸水溶液(B),梯度洗脱,流速为0.8 mL/min;用紫外检测器检测新芒果苷与芒果苷,检测温度为室温,检测波长为265 nm。用蒸发光散射检测器检测知母皂苷BIII、知母皂苷I和知母皂苷AIII,漂移管温度为50 ℃,气体压力为179.1 kPa(26 psi)。知母经炮制后,5种化合物含量均发生了不同程度的改变,表明炮制方法的不同对知母化学成分的含量影响较大。该方法对进一步研究炮制方法对知母的药效学影响提供了一定的参考依据。