Abstract

In this work, we studied protein binders in micro-samples from mural paintings from two 18th century Colonial Andean churches located in the northernmost region of Chile using a proteomic approach. The protein fraction of the samples was extracted with ammonia following a previously optimized methodology and analyzed by LC-MSMS. We identified collagen as well as egg white and yolk proteins, in accordance with a tempera painting technique. In addition, we detected for the first time the presence of muscle proteins in two of the micro-samples. The collagen and muscle proteins could be ascribed to bovine (Bos taurus) and llama (Vicugna pacos), a domesticated camelid used as food source and for transportation of goods in the Andes since pre-Hispanic times. These findings provide new aspects on the knowledge of old animal glues composition and painting practices in the Andean region with reliable information for restoration and conservation work. (c) 2020 Elsevier Masson SAS. All rights reserved.