| China is widely recognized as the country where silk was originated, along with the first invented silkworm breeding and silk reeling. As a quality material, silk was occupied a unique position in costume culture that cannot be overwritten by other materials. Silk were produced into different forms of textiles, whether thick or thin, plain or colorful, sparse or dense, soft or hard, all owing to the exquisite weaving techniques used in ancient China. This made silk not only the main material for costume but also decorative material for headwear and coronet. In the class society of ancient China, like costume, coronet decorations served as signs for the ruling class to show status and class difference, and the ceremonial coronet dressed by ancient Chinese females indicated their supreme status. However, experienced thousands of years of burial, the organic decoration materials, such as silk, were impossible to retain the original macroscopic form and thus bringing difficulty for restoring and studying the ancient coronet decorations.The graves of Emperor Yang and Empress Xiao of Sui Dynasty were found in Yangzhou, Jiangsu, China. A coronet was found in the tomb of Empress Xiao and some textile traces were recognized on the components of the coronet. The research objects of this study are the potential silk protein residues extracted from the soil underneath the coronet. There are two main comments in this paper:optimization of extraction methods of ancient silk protein and extraction and bio-mass spectrometry detection of the textile protein residue in the surrounding soil of Empress Xiao’s coronet.First, the extraction method of the ancient silk protein residues was optimized from two aspects:the dialysis temperature and the molecular weight cut off (MWCO) of membranes, especially for the serious degradation of the ancient samples, in order to achieve the purpose of improving the efficiency of extraction. The results showed that the dialysis at low temperature (4℃) than the room temperature dialysis can get a higher content of silk fibroin solution. The average molecular weight of the protein obtained after dialysis by MWCO2000 was smaller than that of MWCO 14000, which showed that more small molecular weight protein residues were retained. So we established the improved extraction method of dialysis by using MWCO2000 membranes with low temperature (4℃).Then, Lu’an Warring States Huangwei fragments and Mashan No.1 tomb silk fragments were applied as research subjects, two samples were extracted by the improved method. And the effect of the two dialysis methods on the identification results of silk protein was compared by biomass spectrometry analysis. It shows that the method can significantly improve the extraction efficiency of the ancient silk protein, thus enhancing the accuracy and sensitivity of the biomass spectrometry identification method.Finally, the samples from the Empress Xiao’s coronet were detected, the samples were divided into copper decorations samples and soil residue samples. By employing a 3D optical microscopic observation on the copper decorations of the coronet, suspected products of mineralized textiles were found on the surface of some copper flower decorations. Using XRD and FTIR analytical methods to analyze the suspected products of mineralized textiles on the surface of copper flower decorations, and the results show that the main component of the surface mineralization is azurite without protein organic residues. Applying the improved extraction methods to extract and biomass spectrometry analyze the residual protein extracted from the soil underneath the crown. Eight different peptides of silk fibroin (Bombyx mori) are detected. All of them belong to the fibroin heavy chain. By excluding the contamination from ancient silk remains and soil microbial protein, the results indicated that silk was used as decorative material for decorating the Empress’s coronet. The results provided scientific information for the research of rehabilitating the coronet. |
PDF Full Text Request