氨基酸分析法研究蒙古国博格达汗宫建筑彩画的胶料种类

Identification of Binding Media by Amino Acid Analysis from Bogda Cham Palace,Mongolia

为了鉴定博格达汗宫建筑彩画使用的胶料,采用氨基酸分析法测定了古代常用胶料(鸡蛋、动物胶及奶类)的氨基酸组成比。分析3类胶料,发现各胶料的氨基酸组成特点,其中动物胶含羟脯氨酸,且甘氨酸平均含量高达20.45%;鸡蛋中天冬氨酸与脯氨酸的比值较高,平均值为2.29;奶类中谷氨酸与丙氨酸的比值较高,平均值为5.01。在此基础上,分析了蒙古国博格达汗宫建筑彩画样品,对样品的氨基酸组成比进行主成分分析,确定了样品胶料的种类。同时,以动物胶特有的氨基酸——羟脯氨酸(含量均值13.6%)为研究对象,估算出文物样品使用胶料的配方为鸡蛋胶原/动物胶胶原(1.5:1),得出了蒙古国博格达汗宫建筑彩画是采用以鸡蛋为主、动物胶为辅的混合胶料的结论。

To identify the binding media from Bogda Cham Palace,the amino acid analysis was used to distinguish the egg,animal glue and casein which are commonly used as binding media in ancient.From the results of the analysis,the composition characters of these binding media were discovered.The animal glue has a particular amino acid,Hyp,and high content of Gly （average 20.45%）.The ratio of Asp to Pro in egg is high,and the average value is 2.29.The average ratio of Glu/Ala of casein,5.01,is higher than the others.According to the principle component analysis （PCA） of the samples′ amino acid ratios which come from Bogda Cham Palace and the standard binding media′s amino acid ratios,the category of binding media of samples were determined.The composition of the binding media from the samples was estimated by using the Hpro amino acid which is only present in animal glue,the average value is 13.6%.It was con-cluded that the egg was the primary binding media and the animal glue was acci-dental in the drawing of Bogda Cham Palace.The ratio of egg to animal glue is 1.5.