Underneath the Purple Stain

14 páginas.- 11 figuras.- 45 referencias

The Alcobacenses are one of the most important Portuguese collections of Monastic codices. During a campaign study to further advance our knowledge on this important legacy and its state of conservation, a heavily deteriorated codex (ALC.338) stood out due to the presence of purple stains on the lower margins on virtually all folios. In some of them, the purple stains are accompanied by yellow and brown patches as well. Also noticed was the presence of these purple spots on the white tawed leather covering the codex. The codex was analyzed macro and microscopically, chemically and biologically using state-of-the-art technology such as next-generation sequencing. The biological deterioration associated with the appearance of these purple spots arises from the inside out and reveals significant abundance of the bacterial genus Saccharopolyspora sp., which accounted for 86% of the bacterial genera identified. For the fungal population, the most common genus was Malassezia sp. Visual inspection of the sample confirmed the presence of fungal and bacterial biofilms. Pressing questions, comparison to similar studies and future perspectives are also given.

Catarina Pinheiro is under a researcher contract with the HERCULES Laboratory, Évora University (CEECIND/02598/2017) and gratefully acknowledges the FCT/MCTES national support through the UIDB/04449/2020 and UIDP/04449/2020. C.C. acknowledges FCT/MCTES national support through the UIDB/50006/2020 and UIDP/50006/2020. A.Z.M contribution is supported by the Spanish Ministry of Science and Innovation (MCIN) under the Ramón y Cajal contract (RYC2019-026885-I), the CEECIND/01147/2017 research contract from FCT and the intramural project PIE_20214AT021 from the Spanish National Research Council (CSIC). The project under which this work was developed was also funded by FCT through the grant PTDC/ART-HIS/29522/2017.

Peer reviewed