New insights into brazilwood lake pigments manufacture through the use of historically accurate reconstructions     

Tatiana Vitorino  Leslie Carlyle  Vanessa Otero 《文物保护研究》2016,61(5):255-273

A multi-analytical approach for the study of brazilwood and its lake pigments was carried out based on historically accurate reconstructions. Recipes for brazilwood lakes from the fifteenth century technical text Livro de como se fazem as cores and the Winsor & Newton nineteenth century colourman's archive were reproduced and compared. Both primary sources allowed for the successful preparation of brazilwood lake pigments with colours that vary from light pink to dark red. The main steps and ingredients for the manufacture of these pigments were common in both sources, particularly the addition of Al³⁺ in the form of alum, and calcium carbonate (chalk). Reconstructions revealed that the latter acts as a pH buffer and filler, controlling the pH at which the lake pigment precipitates. The main difference between the two sources is that the nineteenth century recipes give the quantities for all ingredients, the precise temperatures and time, and achieved higher relative pigment yields (75% versus 45%). Full chemical characterisation of the reconstructions provided detailed information on the individual steps in the pigment manufacture and revealed that the presence of calcium sulphate dihydrate (gypsum) in the final pigment was a result of its formation in situ. Infrared, reflectance, and fluorescence spectroscopy proved to be essential and complementary techniques: while infrared was used to characterise additives and binders, reflectance and fluorescence data were fundamental for identifying the chromophore. The pigments and paints produced can now be used as standards for the identification and investigation of brazilwood lake pigments found in artworks.  相似文献   

颜填料对不饱和聚酯树脂及原子灰固化的影响     

朱万强 《遵义师范学院学报》2006,8(5):58-60

考察和比较了一系列的原子灰颜填料的作用和功能及对原子灰固化的影响，发现重晶石粉料对不饱和聚酯树腊及原子灰的固化有明显的影响。  相似文献   

天然甘蓝食用色素化学稳定性研究   总被引：3，自引：0，他引：3  

白慧云  宋建荣 《长治学院学报》2006,23(5):51-52

蔬菜花色素是天然食用色素中的一个主要类别,属水溶性色素.甘蓝色素是蔬菜花色素中新近开发的一种.本文测定了甘蓝色素吸收光谱和其在溶液中呈现红紫色的适宜酸度条件,观察了不同pH对该色素的影响和这些添加剂存在下它的光照稳定性.为甘蓝色素的开发应用提供了依据.  相似文献   

糖蜜酒精废液所含色素及其提取研究现状     

李春海  滕俊江  王彩凤  丁桂坤 《茂名学院学报》2011,21(1):21-24

糖蜜酒精废液是利用制糖副产物糖蜜制造酒精所产生的废液,是一个庞大的污染源,对其进行综合治理以保护水资源和生态环境意义重大,在治理的同时回收能源和其他有用的物质,创造经济效益,符合低碳经济的政策和趋势。阐述了糖蜜酒精废液的性质、危害及其处理的现状,介绍了糖蜜酒精废液中的色素组成,以及分离提取糖蜜酒精废液中色素的主要方法。  相似文献   

Red pigment production by Penicillium purpurogenum GH2 is influenced by pH and temperature     

Méndez A  Pérez C  Montañéz JC  Martínez G  Aguilar CN 《Journal of Zhejiang University. Science. B》2011,12(12):961-968

The combined effects of pH and temperature on red pigment production and fungal morphology were evaluated in a submerged culture of Penicillium purpurogenum GH2, using Czapek-Dox media with d-xylose as a carbon source. An experimental design with a factorial fix was used: three pH values (5, 7, and 9) and two temperature levels (24 and 34 °C) were evaluated. The highest production of red pigment (2.46 g/L) was reached with a pH value of 5 and a temperature of 24 °C. Biomass and red pigment production were not directly associated. This study demonstrates that P. purpurogenum GH2 produces a pigment of potential interest to the food industry. It also shows the feasibility of producing and obtaining natural water-soluble pigments for potential use in food industries. A strong combined effect (p<0.05) of pH and temperature was associated with maximal red pigment production (2.46 g/L).  相似文献   

不同方法提取金鸡菊花中天然黄色素及稳定性研究     

晏小欣  贾淑平  赵丽凤 《喀什师范学院学报》2015,(3)

采用冷浸提取、超声波提取及索氏提取法进行研究金鸡菊色素的含量,从而避免了单一方法的局限性。结果表明,超声波提取方法在粗提中显示明显的优势。于此同时,金鸡菊色素具有很好的抗氧化性,并且具有剂量效应关系,在光照和空气下该色素稳定性差,应避光保存。  相似文献   

壮观链霉菌红色素稳定性和抑菌活性的初步研究     

张正波  易小莉  郑怡  裘娟萍 《科技通报》2012,(1):91-94

经过溶剂萃取壮观链霉菌发酵菌体、浓缩萃取液获得色素浸膏,再经过柱层层析、薄层层析从1L的发酵菌体中获得1.06g的红色素纯物质。研究了壮观链霉菌红色素的热稳定性、氧化还原稳定性和pH稳定性;并针对柠檬酸、苯甲酸钠、抗坏血酸和蔗糖等常用的食品添加剂对红色素稳定性的影响进行了探讨,及初步研究了其抗菌生理活性,结果表明:除pH(>7.0)对壮观链霉菌红色素有明显的影响外,高温、食品添加剂等对其稳定性无不良的影响。红色素表现出较好的抗菌(革兰氏阳性菌和啤酒酵母)生理活性。  相似文献   

“红花末”色素理化特性及安全性分析     

王忠合  王军  江晓东  蔡秋儿 《韩山师范学院学报》2013,(6):49-53

为了研究“红花末”色素的理化特性及食用安全性,采用光谱法分析其吸收图谱及光稳定性和热稳定性,并利用小鼠急性毒性试验、小鼠精子畸变试验等方法进行毒理学研究．结果表明,“红花末”色素溶液在200~800 nm有5个吸收峰,可见区最大吸收峰为540 nm．色素光稳定性较差,热稳定性较好．急性毒性试验表明,“红花末”色素对小鼠的LD50值为1259 mg/kg＆#183;bw,属于低毒级;遗传毒性试验表明：小鼠精子畸变率为8.38%~12.26%,明显高于对照组（0.54%,p＆lt;0.05）．“红花末”色素稳定性较好,属于低毒级,具有一定的致突变性,长期食用可能会对生殖系统产生一定的影响.  相似文献   

D-101大孔树脂对蛇莓果实色素吸附行为的研究     

黄龙  庄润彬  黄俊生 《韩山师范学院学报》2013,(6):64-68

以D-101树脂为吸附材料,研究不同条件下对蛇莓果实红色素的吸附和解吸性能．研究发现：静态吸附中上样液温度为30℃时的吸附量较大;动态吸附中上样液酸度为0.5%,吸光度0.179~0.224, pH1.0,流速2 mL/min时的吸附量大;用80%乙醇以2 mL/min的流速进行洗脱时,解吸效果最好;蛇莓果实色素纯化后色价提高了3倍左右,该研究条件科学合理,纯化效果很好.  相似文献   

石斑木果皮红色素稳定性的影响因子     

黄晓昆  黄晓冬  苏志华 《泉州师范学院学报》2008,26(2):110-115

实验研究石斑木果皮红色素的理化性质和光、温度、金属离子、食品添加剂等对色素稳定性的影响．结果表明：该色素在80℃以下较稳定;日光照射,金属离子K^＋、Na^＋、Mg^2＋、Ca^2＋、Cu^2＋、Mn^2＋、Fd^3＋等对色素液的吸光度有明显的不良影响;高浓度VitC和柠檬酸对色素降色明显;蔗糖和苯甲酸钠对色素无较大影响．  相似文献