Assessing the microbiological risk to stored sixteenth century parchment manuscripts: a holistic approach based on molecular and environmental studies

Abstract

The microbial risk for the conservation of seven sixteenth century parchment manuscripts, which showed brown discolouration putatively caused by microorganisms, was evaluated using non-invasive sampling techniques, microscopy, studies of surface-associated and airborne microflora with culture-independent molecular methods, and by measuring repository thermo-hygrometric values. Microscopic observations and ATP assays demonstrated a low level of contamination, indicating that the discolouration was not related to currently active microbial colonisation. Nevertheless, a culture-independent molecular approach was adopted to fully characterise surface-associated communities searching for biodeteriogens that could grow under appropriate thermo-hygrometric conditions. Indeed, potential biodeteriogens and microorganisms that are ecologically related to humans were found, suggesting the need to control the conservation environment and improve handling procedures. Microbial loads of air and thermo-hygrometric measurements showed that the repository was not suitable for preventing the microbial deterioration of parchment. A holistic approach to the assessment of risk of microbial deterioration of documents and heritage preservation is proposed for the first time.

A Combined Approach to Assess the Microbial Contamination of the Archimedes Palimpsest

“…Affiliated with species of the genus Aspergillus and another 2.6 % with Acremonium charticola , a common and emerging mold pathogen in Greece (nonpublished), were 2.6 % of the sequences. Members of the genus Aspergillus [ 40 , 51 – 53 ] and Acremonium [ 52 ] have been described as active biodeteriogen agents on ancient parchments. In addition, 5.3 % of the sequences were related to Hypoxylon spp., from endophytic fungal communities of Taxus chinensis var.…”

Microbiological Analysis of Surfaces of Leonardo Da Vinci’sAtlantic Codex: Biodeterioration Risk

“…From Table 2 it is also clear that the genus Aspergillus is represented by the greatest number of species (6) in the three samples, and among these species A. flavus , A. fumigatus , A. niger , A. terreus , and A. versicolor are those which are found more often in books and documents, representing a potential risk of degradation of the support materials if stored in inappropriate conditions [ 30 – 33 ]. It is also known that the longevity of their spores can range from 2 to 20 years [ 8 , 34 ]. These species together with Eurotium repens and E. amstelodami can also be harmful to humans, for their ability to cause pulmonary invasive aspergillosis, cutaneous infections, keratitis, and allergic reactions [ 24 , 35 , 36 ].…”

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

“…The microbiological picture of the object in question was supplemented by bioluminescence analysis, which showed an average level of organic contamination on the surface of the document, compared with that of other historical objects analyzed in the author's own studies. However, ATP assay gives more reliable results about the bacterial community (7).…”

“…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.…”