10.6092/issn.1973-9494/7121
Gli archivi e le biblioteche custodiscono diverse tipologie di documenti composti da materiali di origine vegetale e animale: carte sciolte e volumi, sia manoscritti che a stampa, fotografi e (negativi e positivi), mappe, stampe, a disposizione del pubblico per esigenze di lettura, studio e informazione. Questa varietà di materiali sono spesso sottoposti a parametri ambientali e micro-ambientali non costanti. Per questo motivo è fondamentale operare sia un controllo costante delle condizioni ambientali sia un campionamento microbiologico sulla superficie, al fine di rallentare i processi di deterioramento.Il monitoraggio del degrado microbiologico di documenti presenti nell’Archivio Storico dell’Osservatorio Astronomico di Palermo ha permesso di rilevare diversi microrganismi (batteri e funghi) che possono essere considerati responsabili del degrado dei documenti analizzati, valutando il reale rischio e le metodologie più idonee per impedire la ricolonizzazione futura.
application/pdf
1973-9494
7121
2
en
Franco Palla
Conservation Science in Cultural Heritage
molecular investigation
Monitoring Biological Damage on Paper-based Documents in the Historical Archive of the Palermo Astronomical Observatory
Text.Serial.Journal
https://conservation-science.unibo.it/
15
Articles
2017-06-01
2017-07-04
2017-06-01
2017-09-04
85-94
CSCH
Franco Palla
2015
10.6092/issn.1973-9494/7121
85
Università degli Studi di Palermo
1973-9494
2
molecular investigation
en
94
Monitoring Biological Damage on Paper-based Documents in the Historical Archive of the Palermo Astronomical Observatory
https://conservation-science.unibo.it/article/download/7121/6831
15
M     ONITORING BIOLOGICAL DAMAGE ON PAPER-BASED
      DOCUMENTS IN THE HISTORICAL ARCHIVE OF THE
      PALERMO ASTRONOMICAL OBSERVATORY

    Marco Di Bella
    Laboratorio di Conservazione e Restauro dei Beni Librari ed Archivistici, Univer-
    sità degli Studi di Palermo, Italy
    Donata Randazzo
    Istituto Nazionale di Astrofisica, Osservatorio Astronomico di Palermo, Italy
    Enza Di Carlo, Giovanna Barresi, Franco Palla*7
    Laboratorio di Biologia e Biotecnologie per i Beni Culturali, STEBICEF, Università
    degli Studi di Palermo, Italy

    Keywords: paper biodeterioration; non-invasive sampling; molecular investigation


    1. Introduction

    As part of the framework in the fourth year of the Book Conservation course at the
University of Palermo, the students’ practical activities were hosted by the Palermo
Astronomical Observatory, which possesses a rich historical archive and library. The
Observatory of Palermo is still located in its original 18th century premises in the me-
dieval tower of the royal palace, consequently, the presence of instruments, books
and documents that have been there since its foundation, today makes it an extremely
interesting place to train the next generation of conservators [1].




                                                                                                      CONSERVATION SCIENCE IN CULTURAL HERITAGE
    The careful conservation of the building and the set-up of a proper museum and
library for this long-established institution has helped solve some major problems that
affected the collections in the past.
    When the books, old instruments and documents lost their scientific value, they
were not always kept in optimal conditions, a factor that reflects their present state. In
a constant effort to preserve their wide ranging heritage, the Observatory welcomed
the presence of three students in book conservation together with their tutor. The Ob-
servatory management was also able to supplement some funds to purchase special
materials needed to carry out the project. The aim was to give the students experience
in activities related to what is called collection care. This involves conservation assess-
ment and stabilization of the damage on a large number of items in order to extend the
life of a collection before it needs extensive or major conservation treatment.
    This work was carried out on several documents on paper and parchment, on printed
and manuscript books and on a number of glass plate negatives. Each item’s condition
was assessed using a specifically designed survey form, photographed and evaluated for
treatment. When treatment was possible in situ, it was carried out in the form of dry cleaning
and small repairs. Among the treated documents, several showed previous mould damage.
    Library and archive material is prone to different kinds of damage which is mainly
physical due to the normal use of the items, chemical, physical and biological when

*   Corresponding author: franco.palla@unipa.it

                                                                                                 85
                                                                                                  environmental conditions are not appropriate or as a result of some accident. Biologi-
                                                                                                  cal damage is one of the higher risks in paper-based collections because attention to
                                                                                                  regular cleaning and monitoring is often absent or neglected. When biological attacks
                                                                                                  occur they affect the substrates and graphic media, creating stains and discolouration.
                                                                                                  If the damage is not detected early enough and promptly treated, it can lead to the total
                                                                                                  destruction of the object [2-4]. Cellulose and collagen-based materials, in certain con-
                                                                                                  ditions, are mostly susceptible to fungal and bacterial deterioration, due to the action of
                                                                                                  specific enzymes (cellulose, proteases, ligninases) and organic acids [5, 6].
                                                                                                      Fungal contamination is also considered a concern because the dispersion of
                                                                                                  spores can contaminate the environment and may produce allergies and other illness-
                                                                                                  es in humans [6, 8]. Depending on the environment, different fungal genera can be
                                                                                                  found, considered to be producers of dangerous mycotoxins that can affect eyes and
                                                                                                  ears [4, 6]. The environmental microorganisms that form the microbial load of indoor air
                                                                                                  at repositories (archives, libraries) storing cultural heritage, can affect human health in
M. Di Bella, D. Randazzo, E. Di Carlo, G. Barresi, F. Palla - MONITORING BIOLOGICAL DAMAGE




                                                                                                  the form of allergies and skin affections [9, 10]. Biodeterioration and health risks justify
                                                                                                  the need to perform periodical microbiological samplings to estimate the prevalence
                                                                                                  of microbial contamination [7, 11]. Knowledge and understanding of the materials from
                                                                                                  which documentary heritage is made and the identification of damage are fundamental
                                                                                                  to carry out any proper conservation treatment [5].
                                                                                                      The aim of this study was therefore, to identify any cultivable microorganisms iso-
                                                                                                  lated from documents in the Archive of Astronomic Observatory in Palermo, in order
                                                                                                  to estimate levels of microbial contamination on the surface of several stored items.
                                                                                                  This research combines information from molecular biology with microbial morphology
                                                                                                  aimed at identifying infecting fungi and bacteria from heritage documents. Four archive
                                                                                                  items, previously colonised by moulds and restored were selected for non-invasive
                                                                                                  samplings by sterile swabs and fragments of nylon membranes in order to detect the
                                                                                                  main microbial re-colonisation [12].
                                                                                                      This work focuses on the biological contamination of paper collections and docu-
                                                                                                  ments and suggests a non-invasive and rapid system of sampling and diagnosis which
                                                                                                  can be adopted for the monitoring of different environments and cultural objects.

                                                                                                     2. Materials and methods

                                                                                                    The sampling was performed in the Astronomical Observatory Historical museum
                                                                                                  (Palermo). Environmental temperature (T) and relative humidity (RH) were measured
                                                                                                  during sampling, using a digital thermo-hygrometer.
                                                                                                    Microbiological sampling was carried out on the surface of 4 historical documents:
                                                                                                    i. AMP - Institutionum Philosophicarum pars tertia utramque Phisicam com-
                                                                                                         plectens. Bound paper manuscript, 1767 (shelf mark: Cart. 78 Fasc. 1);
                                                                                                    ii. IMP - [Boucher, Antoine-Gaspard: d’Argis] Manuale dei periti in materie civili
                                                                                                         [Palermo: dalla tipografia degli eredi Abbate, 1828]. Printed book on paper (Inv.
                                                                                                         10960/BAOA);
                                                                                                    iii. ALE - Catalogo de’ Libri esistenti nella Biblioteca del Reale Osservatorio di Napoli;
                                                                                                         Inventario degli Stromenti Mobili e di ogni altra cosa esistente nel Reale Osserva-
                                                                                                         torio di Napoli. Manuscript quire on paper [1820] (shelf mark: Cart. 77 Fasc. 8);
                                                                                                    iv. ALP - Catalogo dei Libri dal P. Piazzi lasciati all’Osservatorio. Manuscript quire
                                                                                                         on paper [1817] (Cart. 60 Fasc. 2).



                                                                                             86
  Table 1 lists the investigated documents and reports the main alterations of the
analysed documents (Figure 1).

                  Table 1. Biodeterioration evidence on analysed documents.
 Sample                                    Type of document           Type of alteration
                                                                    blackish, pinkish spots
 AMP, Institutionum Philosophicarum
                                              Bound paper         large grayish stain due to
 pars tertia utramque Phisicam com-
                                               manuscript                  humidity
 plectens, 1767
                                                                        loss of material
                                                                        black staining
  IMP, Manuale dei periti in materie       Bound printed book
                                                                         foxing spots
 civili, 1828                                  on paper
                                                                       loss of material
                                                                       pigmented areas
 ALE, Catalogo de’ Libri esistenti nella
                                                                  reddish and greenish spots
 Biblioteca del Reale Osservatorio di      Manuscript on paper
                                                                          and staining
 Napoli, 1820
                                                                        loss of material
                                                                       large violet stain
 ALP, Catalogo dei Libri dal P. Piazzi
                                           Manuscript on paper      black pigmented area
 lasciati all’Osservatorio, 1817
                                                                        loss of material

   Sampling of microbial (fungal and bacterial) structures from damaged archival doc-
uments was carried out using non-invasive methods, and in particular by: i) sterile
nylon membrane fragments (10 cm2) (Hybond, Amersham H+) gently pressed (for 30
seconds) over the investigated area (Figure 2 A); ii) sterile swabs by wiping across
spots showing visible damage and staining (Figure 2 B,C), and then used in culturing
techniques to obtain in vitro growth of the microorganisms.




                                                                                                      CONSERVATION SCIENCE IN CULTURAL HERITAGE




Figure 1. Paper alterations. (A) AMP sample, dark spots and damp patches; (B) ALE sample,
reddish spots, and loss of material; (C-D) ALP sample, violet and greenish stains, and loss of
material.


                                                                                                 87
                                                                                                  Figure 2. Non-invasive sampling on documents. (A) Using nylon membrane and (B-C) sterile
                                                                                                  swabs, in ALP and IMP samples, corresponding to pigmented areas and fragile portions of the
                                                                                                  paper.
M. Di Bella, D. Randazzo, E. Di Carlo, G. Barresi, F. Palla - MONITORING BIOLOGICAL DAMAGE




                                                                                                      For each document, two samplings using nylon membranes and one sampling us-
                                                                                                  ing sterile swabs were performed in those areas mainly affected by pigmentation, dis-
                                                                                                  coloration, foxing phenomena and loss of material.
                                                                                                      After sampling, the nylon membrane fragments were immediately transferred onto
                                                                                                  Petri-dishes containing nutritive solid media in order to isolate bacteria (Nutrient Agar,
                                                                                                  Difco) and fungi (Sabouraud, Difco). Microbial particles collected by sterile swabs were
                                                                                                  firstly suspended in culture liquid media (Nutrient Broth, Difco) and then seeded onto
                                                                                                  appropriate solid nutritive media. All Petri dishes were incubated at 30°C for 48-72
                                                                                                  hours.

                                                                                                     2.1 Microbial identification

                                                                                                      The identification of microbial taxa was carried out using an integrated approach
                                                                                                  based on in vitro culture, microscopy analysis and molecular investigation. Particularly,
                                                                                                  filamentous fungi structures and reproductive propagules were observed through opti-
                                                                                                  cal microscopy (Leica, 40X) after Lugol’s solution staining [12].
                                                                                                      Phylogenetic identification was performed by molecular investigation based on mi-
                                                                                                  crobial genomic DNA analysis. DNAs were directly extracted from bacterial and fungal
                                                                                                  colonies using a commercial kit (Genomic DNA Purification kit, Fermentas) and utilized
                                                                                                  as templates in in vitro amplification of specific genomic target sequences by Poly-
                                                                                                  merase Chain Reaction (PCR). Particularly, the target sequences correspond to the
                                                                                                  Internal Transcribed Spacer 18-26S for fungi and 16-23S for bacteria. PCR products
                                                                                                  were analyzed on agarose gel (2%) in TAE solution (TRIS-HCl/acetate/EDTA).
                                                                                                      PCR products were sequenced by Eurofins MWG Operon sequencing-service and
                                                                                                  the sequences analysed by BLAST platform [12, 13].

                                                                                                     3. Results

                                                                                                     Several microorganisms (bacteria and fungi) were isolated using culture-dependent
                                                                                                  techniques and characterized by molecular investigations, as reported in Table 2.
                                                                                                     The characterization of isolated fungi was carried out through microscopic analy-
                                                                                                  sis (Figure 4), showing that Penicillium was the predominant genus in all documents,
                                                                                                  while Aspergillus niger was detected only in the AMP document.



                                                                                             88
   Bacterial colonies belonging to Bacillus genera were isolated from all documents,
distinguishing AMP (Bacillus spp.), IMP and ALE (B. simplex, B. flexus). Micrococcus
spp. was revealed in IMP, and Micrococcus luteus in ALE and ALP. Arthobacter spp.
was isolated only from the ALP sample.

                       Table 2. Isolated and characterized microorganisms.

 Microorganisms                         AMP            IMP            ALE          ALP

 Fungi
            Aspergillus niger            +               -              -           -
            Penicillium spp.             +              +              +            +
 Bacteria
            Arthobacter spp.             -               -              -           +
            Bacillus simplex             -               -             +            -
            Bacillus flexus              -               -             +            -
            Bacillus spp.                +              +               -           -
            Micrococcus spp.             -              +               -           -
            Micrococcus luteus           -               -             +            +

                                   Presence (+); Absence (-)

   Fungal taxa revealed in this study, belonging to Deuteromycetes, are environ-
mental and widespread fungi, capable of colonizing several organic substrates
(such as cellulosic materials) as a source of nourishment. Their presence in in-




                                                                                                     CONSERVATION SCIENCE IN CULTURAL HERITAGE
door environments, such as archives or libraries, could induce allergies and skin
infections [14]. Bacteria isolated in this study are often found on organic materials
producing stains of different shape and color and are generally associated with
chromatic alterations.




Figure 3. AMP samples, fungi colonies grown on nylon membranes in Sabouraud medium (A);
Light microscopic observations (40X) following Lugol staining of (B) Penicillium spp. and (C)
Aspergillus niger.



                                                                                                89
M. Di Bella, D. Randazzo, E. Di Carlo, G. Barresi, F. Palla - MONITORING BIOLOGICAL DAMAGE




                                                                                                  Figure 4. Macro-photos of Penicillium spp. colonies growing on nylon membranes after samplings
                                                                                                  from ALP and Petri dish growth.



                                                                                                     4. Conservation treatment

                                                                                                      Since the microorganisms responsible for the biological damage were no longer
                                                                                                  active and the original material was not wet, it was possible to carefully dry clean by
                                                                                                  brush every single page. The procedure was carried out in an open area to prevent
                                                                                                  spread of the spores within the museum environment. This allowed the deposits and
                                                                                                  mold remains to be removed [15]. In the areas that were more severely affected by
                                                                                                  the infection the support had suffered from partial weakening and thus required some
                                                                                                  consolidation. Since simple re-sizing was not enough to give the necessary flexibility
                                                                                                  and support to the affected area, it was decided to line the fragile area with Japanese
                                                                                                  tissue, only on one side. The use of a water-based adhesive was avoided due to the
                                                                                                  weakness of the paper and also to avoid introducing unnecessary moisture on an area
                                                                                                  already affected by microbiological attack. Klucel G (hydroxypropyl cellulose), diluted
                                                                                                  in ethanol (3% w/v) was then selected and applied by brush over the Japanese tissue.
                                                                                                      Many of the items treated during the training period were provided with a custom-
                                                                                                  made archival cardboard folder or box. The use of protective enclosures reduces the
                                                                                                  impact of the environment on the items. A box or a folder will stop the direct effect of
                                                                                                  light and dust; it has been proved that enclosures also have a mitigating effect in the
                                                                                                  event of fires and floods. All the enclosures were made of specifically produced fold-
                                                                                                  ing box board, with enhanced wear and tear strength so as to endure the mechanical
                                                                                                  stress of the opening and closing of the container and to resist abrasion from shelv-
                                                                                                  ing and handling. The cardboard is made of pure cellulose with alkaline buffer to be
                                                                                                  chemically safe for the boxed contents and at the same time, being an organic porous
                                                                                                  material, it absorbs and releases moisture before it can come in contact with the docu-
                                                                                                  ments, playing a buffering action for environmental fluctuations (Figure 5).


                                                                                             90
            Figure 5. Protective boxes for correct storage of archival documents.



  5. Conclusions

    In the present study, a dry cleaning procedure and consolidation of some documents
stored in Palermo Astronomical Observatory’s historical archive and library were car-
ried out. Moreover, optical, culture-based and molecular analyses were carried out to
determine the extent of the microbial deterioration of the paper-based objects. Dis-
coloration and coloured spots, mainly reddish and blackish, alterations probably due
to the microbial activity (past or present) were observed on investigated paper-based




                                                                                                  CONSERVATION SCIENCE IN CULTURAL HERITAGE
objects. Dark fungal isolates of Aspergillus niger were identified after observation of
the black-spotted sampling areas (in particular the AMP sample). In all samples, Peni-
cillium spp. was the main species isolated.
    In relation to bacteria, Bacillus spp. was the predominant species able to excrete
hydrolytic enzymes and has already been isolated from archives affected by foxing and
paper [16]. Arthobacter spp. and Micrococcus spp. contamination was found mainly
in ALE and in ALP samples; in paper, their metabolic activity can induce discoloration
and staining. These microbial taxa can contribute to structural degradation, acting
both mechanically (fungal hyphae growth) or chemically (microbial enzymes or acid
extraction).
    However, the total microbial loads were considered of no risk for the integrity of the
analyzed documents. Most of the structural alterations and stains are the result of past
colonization by some microbial deteriogens that are no longer metabolically active.
    To prevent further occurrence of biological damage, regular cleaning, periodical as-
sessment and environmental monitoring is recommended. In addition, the buffering
action of the protective enclosures will prevent the effect of possible fluctuations in
environmental parameters and protect from dust and spores, thereby, further reducing
risks.




                                                                                             91
                                                                                                        References

                                                                                                  [1]     Randazzo, D., (2013) La biblioteca scientifica di Giuseppe Piazzi (1746-1826):
                                                                                                          libri di matematica, fisica e astronomia. In Atti Convegno SISFA 2013, in press.
                                                                                                  [2]     Borrego, S., Lavin, P., Perdomo, I., Gómez de Saravia, S., Guiamet, P., (2012)
                                                                                                          Determination of Indoor Air Quality in Archives and Biodeterioration of Documen-
                                                                                                          tary Heritage, ISRN Microbiology, 2012, pp. 1-10.
                                                                                                  [3]     Lourenco, M.J.L., Sampaio, J.P., (2005) Microbial deterioration of gelatin emul-
                                                                                                          sion photographs: isolation of contaminant microorganisms from three collec-
                                                                                                          tions, Conservar Património, 2, pp. 13-19.
                                                                                                  [4]     Da Costa, A.C.A., Corrêa, F.D.N., Lino, L.A.S, De Almeida, E.H.P., De Oliveira,
                                                                                                          A.L.C., Lutterbach, M.T.S., (2014) Microbial Characterization of contaminating
                                                                                                          cells on scientific collections in a specialized library, Annual Research & Review
                                                                                                          in Biology, 4(24), pp. 3915-3931.
M. Di Bella, D. Randazzo, E. Di Carlo, G. Barresi, F. Palla - MONITORING BIOLOGICAL DAMAGE




                                                                                                  [5]     Pinzari, F., Troiano, F., Piñar, G., Sterflinger, K., Montanari, M., (2011) The Con-
                                                                                                          tribution Of Microbiological Research in the Field of Book, Paper and Parchment
                                                                                                          Conservation. In: Engel P., Schirò J., Larsen R., Moussakova E., Kecskeméti
                                                                                                          I., (eds.), New Approaches to Book and Paper Conservation-Restoration. Horn/
                                                                                                          Wien: Verlag Berger, pp. 575-594.
                                                                                                  [6]     Valentín, N., (2007) Microbial Contamination in Archives and Museums: Health
                                                                                                          Hazards and Preventive Strategies using Air Ventilation Systems. Proceedings
                                                                                                          of the Experts’ Roundtable on Sustainable Climate Management Strategies, Ten-
                                                                                                          erife, Spain. The Getty Conservation Institute, pp. 1-26.
                                                                                                  [7]     Mesquita, N., Portugal, A., Videira, S., Rodrìguez-Echeverrí, S., Bandeira, A.M.L.,
                                                                                                          Santos, M.J.A., Freitas, H., (2009) Fungal diversity in ancient documents. A case
                                                                                                          study on the Archive of the University of Coimbra, International Biodeterioration
                                                                                                          & Biodegradation, 63(5), pp. 626-629.
                                                                                                  [8]     Michaelsen, A., Piñar, G., Pinzari, F., (2009) Biodeterioration and restoration of a
                                                                                                          16th-century book using a combination of conventional and molecular techniques:
                                                                                                          A case study, Internation Biodeterioration & Biodegradation, 63(2), pp. 161-168.
                                                                                                  [9]     Sahab Ahmed, F., Sidkey Nagwa, M., Abed Nermine, N., Mounir Ayah, (2014)
                                                                                                          Studies on indoor air quality in the repositories of the National Library and Ar-
                                                                                                          chives of Egypt, International Journal of Science and Research, 11, pp. 1-7.
                                                                                                  [10]    Borrego, S., Guimet, P., Gómez de Saravia, S., Batistini, P., Garcia, M., Lavin, P.,
                                                                                                          Perdomo, I., (2010) The quality of air at archives and the biodeterioration of pho-
                                                                                                          tographs, International Biodeterioration & Biodegradation, 64(2), pp. 139-145.
                                                                                                  [11]    Palla, F., (2012) Analytical techniques. In: Fabbri B. (ed.), Science and Conser-
                                                                                                          vation for Museum Collections. Firenze: Nardini Editore, pp. 459-470.
                                                                                                  [12]    Palla, F., Federico, C., Russo, R., Anello, L., (2002) Identification of Nocardia
                                                                                                          restricta in biodegrated sandstone monuments by PCR and nested-PCR DNA
                                                                                                          amplification, FEMS Microbiology Ecology, 39(1), pp. 85-89.
                                                                                                  [13]    Palla, F., Barresi, G., Di Carlo, E., (2014) Identification of bacterial taxa in Ar-
                                                                                                          chaeological waterlogged wood, Conservation Science in Cultural Heritage,
                                                                                                          14(14), pp. 247-262.
                                                                                                  [14]    Di Carlo, E., Chisesi, R., Barresi, G., Barbaro, S., Lombardo, G., Rotolo, V., Se-
                                                                                                          bastianelli, M., Travagliato, G., Palla, F., (2016) Fungi and Bacteria in Indoor
                                                                                                          Cultural Heritage Environments: Microbial-related Risks for Artworks and Human
                                                                                                          Health, Environment and Ecology Research, 4(5), pp. 257-264.


                                                                                             92
[15] Child, R., (2011) Mould outbreaks in library and archive collections. British Li-
     brary guidance booklets. London: The preservation Advisory Centre.
[16] Borrego, S., Lavin, P., Perdomo, I., Gómez de Saravia, S., Guimet, P, (2012)
     Determination of Indoor Air Quality in archives and Biodeterioration of the Docu-
     mentary Heritage, ISNR Microbiology, 2012, pp. 1-10.


  Biographical notes

   Marco Di Bella, freelance book conservator, graduated at the European Course for
Conservators-Restorers of Book Materials in Spoleto (Italy) in 2001; he has worked
in conservation, assessment and training projects for the Camberwell College of Arts
(UK), UNESCO, Yemeni Social Fund for development, ISCR, ICPAL, National Ar-
chive of Tripoli (Libya), University of Palermo, the Hiob Ludolf Center for Ethiopian
Studies (Hamburg University), the American University of Beirut. He has worked for
private book conservation studios in Italy and lectured in international conferences,
researched and published on archaeology of early Islamic bookbinding and book con-
servation. Since 2015, he is senior manuscript conservator at Trinity College, Dublin.
   Donata Randazzo has a degree in Biology and graduated as a “Librarian” in Eng-
land, she is librarian of Palermo Astronomical Observatory, where she takes care es-
pecially of the Old and the Historical Fund. She collaborated in the compilation of the
biographical repertoire of Italian astronomers and inventory of the Palermo Observa-
tory Historical Archive.
   Enza Di Carlo has a Master’s Degree in “Biological Science” from the University of
Palermo and specialized in “Microbiology and Virology” at the School of Medicine at the
same University. She is a Research Fellow at the Laboratory of Biology and Biotechnolo-
gies for Cultural Heritage of the Department of Biological, Chemical and Pharmaceutical




                                                                                                 CONSERVATION SCIENCE IN CULTURAL HERITAGE
Sciences and Technologies (STEBICEF) at the University of Palermo, where she has
carried out microbiological monitoring of Cultural Heritage environments.
   Giovanna Barresi has a Master’s Degree in “Science for Conservation and Resto-
ration” from the University of Florence. She has been a Research Fellow since 2013
at the Laboratory of Biology and Biotechnologies for Cultural Heritage, Department of
Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF) at
the University of Palermo. She works in the field of diagnostic-analytical studies and
applied research for the enzymatic cleaning of artifacts of historical-artistic interest.
    Franco Palla is Associate Professor of Applied and Environmental Botany at the
University of Palermo, Italy. He is Professor and Coordinator of the Five-Year De-
gree in Conservation and Restoration of Cultural Property (MRL02, certified profes-
sional restorer). He is scientific head of UNIPA Research Unit, for the Research Project
PON01_00625, It@cha (Italian Technology for Advanced Applications in Cultural Her-
itage). He was one of the members of the working groups in the cooperation project
Italy-Cambodia for Training Experts of Cultural Heritage, University of Palermo – Royal
University of Fine Arts and the Ministry of Culture and Fine Arts, Angkor, Cambodia. He
is Coordinator of the Laboratory of Biology and Biotechnologies for Cultural Heritage at
the Department of Biological, Chemical and Pharmaceutical Sciences and Technolo-
gies (STEBICEF) of the University of Palermo.


                                                                                            93
                                                                                                     Summary
                                                                                                     Libraries and archives house a wide variety of documents made of materials of
                                                                                                  vegetal and animal origin: unbound papers and books, manuscripts and printed books,
                                                                                                  photographs (negative and positive), prints, maps, available to the public for read-
                                                                                                  ing needs, study and information. These materials are often subject to fluctuations in
                                                                                                  environmental and micro-environmental parameters. For this reason, it is essential to
                                                                                                  implement constant monitoring and control of environmental conditions and potential
                                                                                                  deteriogens in order to slow down deterioration processes.
                                                                                                     The monitoring of the microbial degradation of paper documents in the Historical
                                                                                                  Archives of Palermo Astronomical Observatory has revealed microorganisms (bacteria
                                                                                                  and fungi) that may be considered responsible for damaging the items examined, thus
                                                                                                  enabling an evaluation of the real risks and the proper methodologies to use to avoid
                                                                                                  future recolonization.
M. Di Bella, D. Randazzo, E. Di Carlo, G. Barresi, F. Palla - MONITORING BIOLOGICAL DAMAGE




                                                                                                     Riassunto
                                                                                                     Gli archivi e le biblioteche custodiscono diverse tipologie di documenti composti
                                                                                                  da materiali di origine vegetale e animale: carte sciolte e volumi, sia manoscritti che
                                                                                                  a stampa, fotografie (negativi e positivi), mappe, stampe, a disposizione del pubblico
                                                                                                  per esigenze di lettura, studio e informazione. Questa varietà di materiali sono spesso
                                                                                                  sottoposti a parametri ambientali e micro-ambientali non costanti. Per questo motivo
                                                                                                  è fondamentale operare sia un controllo costante delle condizioni ambientali sia un
                                                                                                  campionamento microbiologico sulla superficie, al fine di rallentare i processi di dete-
                                                                                                  rioramento.
                                                                                                     Il monitoraggio del degrado microbiologico di documenti presenti nell’Archivio Sto-
                                                                                                  rico dell’Osservatorio Astronomico di Palermo ha permesso di rilevare diversi micror-
                                                                                                  ganismi (batteri e funghi) che possono essere considerati responsabili del degrado
                                                                                                  dei documenti analizzati, valutando il reale rischio e le metodologie più idonee per
                                                                                                  impedire la ricolonizzazione futura.




                                                                                             94
