Unmasking the measles‐like parchment discoloration: molecular and microanalytical approach

Abstract

Many ancient parchments are defaced by red or purple maculae associated with localized destruction of collagen fibres. Although the main characteristics of this damage were present in most of the manuscripts analysed by many authors, no common microbial or fungal denominator has been found so far, and little or no correspondence between the microbial or fungal species isolated from materials could be addressed. In this study, culture-independent molecular methods and scanning electron microscopy (SEM) were used to identify fungal and bacterial communities on parchments affected by the purple stains. Protocols for c extraction and nucleic-acid-based strategies were selected for assays examining the community structure of fungi and bacteria on biodeteriorated parchment. Both SEM and molecular analysis detected the presence of bacterial and fungal cells in the damaged areas. Halophilic, halotolerant proteolytic bacterial species were selected by the saline environment provided by the parchment samples. As common microbial denominators, members of the Actinobacteria, mainly Saccharopolyspora spp. and species of Aspergillus, were detected in all investigated cases. It is proposed that a relationship exists between the phenomenon of purple spots on ancient parchments and that of the ‘red heat’ phenomenon, known to be present in some products manufactured with marine salt.

Evaluation of a Parchment Document, the 13th Century Incorporation Charter for the City of Krakow, Poland, for Microbial Hazards

“…There were, among others, microbes of the Penicillium, Aspergillus, Trichoderma, Alternaria, and Chaetomium genera. According to literature reports, the fungal profile obtained constitutes a typical microflora of parchment documents (5,6,18,35,36). The dominating fungal isolates obtained from the surface of the document included P. chrysogenum, which has also been isolated by Krakova et al (36), and C. globosum, previously reported by Mesquita et al (18) and Strzelczyk (21).…”

“…The SEM analysis revealed structural changes as well as the uncovering and destruction of collagen fibers induced by bacterial growth and enzymatic activity. Structural changes caused by the biodeterioration of parchment documents and identified using SEM analysis have been previously described (5,6). The greatest changes were observed for A. lwoffii.…”

“…The problem of microbial hazards of archival items is broadly addressed in the literature (3)(4)(5)(6)(7). Collections of written documents are a particular type of cultural heritage object, since they are carriers of broadly understood historical and cultural knowledge.…”

“…As a result of these technological processes, the parchment product consisted of the inner collagen layer, with its typical fiber arrangement, and external gelatin layers (8)(9)(10). As with other materials that carry writing, such as paper and leather, parchment is subject to the process of biodeterioration (3,5,(11)(12)(13). This process consists of the microbial enzymatic degradation of the organic components of these materials, which in the case of parchment is mainly collagen and in the case of paper is mainly cellulose (13,14).…”

Pulsed Thermography Applied to the Study of Cultural Heritage

“…Ancient manuscripts and documents are often affected by different forms of deterioration and physical degradation phenomena, due to a combination of factors-such as environmental conditions, dirt, effects of natural disasters, handling, and biological attacks-all causing the loss of readability of their textual elements [74]. IRT has proved to be able to recover many of the elements belonging to the surface of the artefacts, like texts on parchment or leather, that have become invisible to a simple optical inspection.…”