THE ROLE OF MICROORGANISMS IN THE DECAY OF PARCHMENT

The role of fungi, true bacteria and streptomycetes in the decay of ne w and historical parchment is discussed. True bacteria usually attack strongly humudified or inundated parchement turning it into a darkened sticky mass. On parchment stored under high relative air humidity con ditions (95 - 100%) there appear numerous colonies of fungi (Aspergill us sp., Epicoccum sp., Penicillium sp. etc.) and streptomycetes causin g coloured stains and holes. The collagen losses caused by various gro ups of microorganisms were determined. SEM investigations of deteriora ted parchment samples revealed deep damages of collagen fibres (pits, cracks, splittings). The active role of streptomycetes in the decompos ing of parchment is underlined.