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A deacidifying/antifungal mixture composed of calcium propionate, methylparaben and propylparaben was tested against Aspergillus niger , Cladosporium cladosporioides , Chaetomium globosum , Penicillium chrysogenum and Penicillium corylophilum . The preventive treatment of paper samples resulted in a complete fungal growth inhibition on 4 of the 5 tested species. The antifungal properties of the formulation remained unaffected for a minimum period of one year. The disinfecting treatment with the mixture led to a total elimination of all tested fungal species. The effects of the tested formulation on paper were evaluated in terms of pH, colourimetry, folding endurance, FTIR and XRD, using moist heat artificial ageing. Aside from plain paper, paper previously colonized by A. niger was tested to evaluate the potential of the formulation in preventing deterioration caused by fungal metabolites. In plain paper, an effective deacidification and long-term prevention of mechanical resistance loss were achieved, although a slight paper discoloration occurred. On previously colonized by fungi, the treatment effectively prevented the deterioration caused by fungal metabolites. [ABSTRACT FROM AUTHOR]

Volumes from an archive of the University of Milan showed whitish-grey discolouration putatively caused by microorganisms. Microscopic and viability assays proved that discolouration from two volumes were characterized by a marked presence of viable fungi, demonstrating that they were mainly biological in nature. Fungal sequences were phylogenetically most closely related to Eurotium , Aspergillus , Candida , Penicillium , Alternaria , Phaeosphaeria , Capnodiales and Pleosporales taxa. SEM analysis showed that Eurotium halophilicum is dominant on the two infected volumes. Viable airborne fungal loads near the two volumes were higher than recommended maximum values, demonstrating that airborne fungi could represent a source of risk. The airborne microbial community sampled in two different seasons was composed by fungi belonging in the genera Aspergillus , Candida and Eurotium . The detection of E. halophilicum also in the archival air indicated a possible source of contamination. Fluctuations of thermo-hygrometric values were also observed in the archive in the different seasons. The occurrence of white efflorescence on the stored volumes most likely depended on the lack of both a dusting programme and air-conditioning, and insufficient ventilation in the repository, and, on the hygroscopic behaviour of the binding materials used in the manufacture of the volumes. [ABSTRACT FROM AUTHOR]

In the past, the animal glues were used in paper manufacturing and in restoration of artworks preserved in museums, libraries and archives. By ageing they went through deterioration creating distortions, tensions, cockling and discolouration in paper materials. Consequently, the removal of glue residues becomes an essential step in the restoration of ancient and artwork paper material. Current mechanical and chemical methods display serious drawbacks mainly related to aggressiveness towards material or toxicity for restorers. Bio-based methods for paper cleaning rely on the use of enzymes that require skilled operators, optimal application conditions and high costs, creating difficulties in mastering enzyme use so far. This paper describes a first attempt of biocleaning ancient paper from organic deposits using living bacteria. The non-pathogenic, non-spore-forming and non-cellulolytic original strain Ochrobactrum sp. TNS15 E was successfully applied -immobilised in an agar gel-on original paper specimens dating back to the 17th. After 4 h of contact with the bacterial pack, the cellulose fibres underlying glue were disclosed, highlighting the bacterial capacity of removing the glue layer without damaging the paper or leaving undesirable residues. Both colorimetry and SEM analyses proved the results. The procedure is simple, low-cost and safe for the artefact, the restorers and the environment. [ABSTRACT FROM AUTHOR]

In order to examine the potential efficacy of simultaneous dual-species fungal treatment of wood for lignocellulosic ethanol production, whole organism fungal biopulping methods utilizing white rot ( Ceriporiopsis subvermispora ) and brown rot ( Postia placenta ) fungi alone or in co-culture were compared for effect on wood microstructure, chemical composition, and enzymatic sugar solubilization. Liriodendron tulipifera wood chips exposed for 30 days to C . subvermispora and/or P . placenta fungi alone or in co-culture exhibited qualitative differences in wood microstructure, but did not significantly differ in final percent composition of holocellulose, α -cellulose, or lignin content compared to controls. All fungal treatments increased the soluble reducing sugar yield of enzymatic hydrolysis by ca. 28–30% over sterile controls. The co-culture fungal treatment did not significantly differ in reducing sugar yield compared to monoculture treatments, suggesting an unexpected lack of additive or other synergistic species effects on wood degradation using these fungi in co-culture. Paired interaction agar plate assays demonstrated that C . subvermispora and P . placenta exhibited mutual distance-mediated growth inhibition that was independent of substrate type or availability, suggesting an explanation for the observed lack of degradative synergy between these taxa. This study is the first to report the effects of simultaneous co-treatment with white and brown rot fungi, highlights the need for further optimization of methods to account for specialized fungal degradative mechanisms, and examines the potential influence of competitive interactions in whole-organism biopulping treatments utilizing different taxa. [ABSTRACT FROM AUTHOR]