A First Assessment of the Conservation of the Mummified Human Remains in the Museo Egizio in Turin in the Framework of the “Mummy Conservation Project”

:ثحبلا صخلم يوتحي لا فحتم يرصملا ونيروت يف ىلع ةديرف ةعومجم ت ض م نيب ام ةعطق يموم ا و تا ةطنحم ةيرشب أ و يه ا يمظع لك ة وأ ءازجأ ةيرشب ةطنحم ايلاح . ديق ةعومجملا هذه ايموملا ىلع ظافحلا عورشم" لبق نم ةساردلا تاو ينواعت عورشم وه ،" نيب ام ا حتمل ف يرصملا دهعمو و كاروي ثاحبلأ ءايموملا تاسارد بتكم ظافحلا ىلع ثارتلا يرثلأا يف يتنومييب ةعطاقم ةعومجمو ايموملا ىلع ظافحلا تاينقت نيسحت ىلإ فدهت يتلا ،سروح تاو . اطن يف ق ظفحلا ةلاح مييقت مت ،عورشملا اذه ل ةيرشبلا اياقبل ةبقارم للاخ نم ةطنحملا طاشنو ةيبسنلا ةبوطرلاو ةرارحلا ةجرد( ةيساسلأا ةيئايزيفلا لماوعلا تائيزجلا يئاملا ة حسم ءارجإو ) لل طف و دوجو نع ةريخلأا هذه تفشك .ر تايرتكبو روطف ةيرطف لا ىلع داوم لا م ةطنح نأ نكمي يتلاو يدهت لكشت يويحلا للحتلاب اد . و عيمج رهظت كلذ عم ةيئايزيفلا سيياقملا ةيلاحلا يأ طبثت فوس يتلاو ،ةيلاثم ةيئيب فورظ لظ يف اهنيزخت متي تاوايموملا نأ ومن ل ابوركيمل .ت Samadelli, Marco et al., “A First Assessment of the Conservation of the Mummified Human Remains in the Museo Egizio in Turin in the Framework of the ‘Mummy Conservation Project’ ”, Rivista del Museo Egizio 3 (2019). DOI: 10.29353/rime.2019.2765


Introduction
The first set of Egyptian mummies arrived in Turin following the scientific/commercial expedition undertaken by the traveler and naturalist, Vitaliano Donati, a professor of botany at the University of Turin, at the behest of King Charles Emmanuel III of Savoy between 1759 and 1762. In Egypt, Donati collected some 1,689 scientific samples and objects, 1 including eighteen animal mummies. A second group of mummies, many probably coming from the ancient Egyptian capital city of Thebes (modern-day Luxor in southern Egypt), was collected by Bernardino Drovetti, Consul General of France to Egypt, and was bought, for the Turin collection, by the Savoy king Charles Felix in 1824. 2 In 1888, when the two-volume catalogue of the Museo Egizio was completed by Ariodante Fabretti (1816-1894), Francesco Rossi (1827-1912 and Rodolfo Vittorio Lanzone (1834-1907, it included a total of twelve complete human mummies, nine heads -two of which were associated with a hand -two hands with rings, four pseudo-mummies, and seventy-eight animal mummies. The human mummies entered the collection inside wooden anthropoid coffins, and the inscriptions that grace these coffins specify the names and professions of the deceased they were meant for, supposedly the same people whose mummified bodies were contained in the coffins. 3 Finally, thanks to Ernesto Schiaparelli, director of the Museo Egizio between 1894 and 1928, the number of mummies in the collection was further increased. A buying trip to Egypt, done by Schiaparelli in 1900Schiaparelli in /1901  Project" was set up, with the aim of incorporating the data and knowledge acquired so far on these human remains in order to develop a protocol for proper museum conservation and display.
The goals of the "Mummy Conservation Project" illustrated in this paper were the following: • Taking thermo-hygrometric measurements in the galleries, the inside of display cases, in the mum-my storage room, and in the room where the research operations were carried out.
• Measuring the water activity (aw) of the mummies. • Fungal spore sampling of the air in the galleries, inside a display case, in the mummy storage room, and in the room where the research operations were carried out.
• Fungal survey of the mummified material.

Research aim
In view of the Museo Egizio and Eurac Research's common interest in developing know-how to help preserve all the Museo Egizio's mummies -both those on display and those in storage -special emphasis was placed on testing water activity (aw), a parameter that affects the rate of biochemical decay in organic tissues. This important parameter is significantly affected by temperature and relative humidity in the conservation environment. In parallel to the assessment of this physical parameter, a first microbial survey was performed.
To identify the presence of possible superficial growing fungi, samples of both textiles and skin were taken using non-invasive contact plates.
To obtain further knowledge of the environmental conditions the mummies are presently experiencing, the researchers also took samples of spores present in the air inside the storage room where the mummies were kept, in a display case in the permanent galleries, and in the room where the research operations were carried out.
The aim of this work is to expand on research on the conservation organic objects of historical and artistic interest by assessing both biological and physical-chemical conservation requirements.

Material and methods
3.1 Thermo-hygrometric measurement of the exhibition areas, inside a display case, in the mummy storage room, and in the room where the research operations were carried out Thanks to historical data relative to the thermo-hygrometric conditions of the museum's exhibition spaces and the storage space where the mummies were kept (prior to the inauguration of the new galleries in 2015), it was possible to identify the sea-sonal trend these relics were subjected to.
With the exception of the room where the Tomb of Kha and Merit was display -where a wall-mounted air conditioner and a portable humidifier were installed -all the rest of the museum and storage lacked an air conditioning system. Climate monitoring took place in "sample" mode over different periods and in different areas of the museum with the aid of data loggers (HumiStick). The recorded temperature ranged between 21 °C and 30 °C, and the recorded relative humidity between 30 % and 66 %.
In 2015, a new air conditioning system was installed, serving all the exhibition halls, the Foundation's offices, and the storage spaces. It is powered by an underground thermo-cooling plant using geothermal energy.
To date, the museum's different exhibition areas have depended on auxiliary machines whose temperature and relative humidity values can be individually and independently set.

Measuring water activity (aw) of the mummies
As regards this specific phase of the project, a total of 106 organic samples were analysed, both of a vegetal nature (bandage linen) and of human origin (fragments of bone, skin, muscles, connective tissue, hair, Fig. 1).
To measure the water activity (aw) value, the Rotronic instrument, model HygroPalm HP-23-AW-A, was used. Prior to measuring the samples, the HC2-AW and the relative Rotronic HC2-SH measurement probe were calibrated as needed.
Immediately after sampling the mummified organic tissues, the water activity of the samples was examined. The samples were then placed inside special sample holders, previously sterilised. The Rotronic HW4 software version 3.8.0 was used to validate the measurements obtained. Once the PC was connected to the analyser, it was possible, through this application, to set the necessary operating settings in order to obtain the measurement (Fig. 2).
Simultaneously with the water activity (aw) acquisition phase, the temperature and relative humidity values of the environment were obtained. The time required to acquire each sample is approximately 5 minutes. At the end of each acquisition, a validation certificate was produced in form of a PDF file.

Sampling and cultivation of fungi
Non-invasive sampling using contact agar plates (DG18 and 2 % MEA, Merck) was performed as pre-

DNA extraction, PCR amplification and sequence analysis
Pure cultures were identified based on the sequencing of internal transcribed spacer region (IT-SI-5.8S-ITSII), a sequence that can be used as a phylogenetic marker. DNA was extracted from the purified cultures using fresh mycelia, as described by Michaelsen et al. 7 For the analysis of fungal ITS sequences, we PCR amplified this genomic region using specific ITS primers, 8 using the conditions described by Pinar et al. 9 To identify the fungi, we compared the obtained sequence material to fungi ITS sequences available in the online public database NCBI, using the BLAST search program. 10

Results and discussion 4.1 Observations on the results of water activity (aw) analysis
Water activity analysis is a widely-used technique in food storage control. 11 Its application in the field of cultural heritage conservation, on mummified biological samples, is innovative and pioneering.
The importance of relative humidity (RH) to conservation is immense, 12 and closely linked to the concept of water activity (aw), the parameter proportional to the escaping tendency of the water molecules present in the tissues constituting the mummy. Water activity (aw) is calculated as the ratio of the partial vapour pressure of water in tissues (Pw) to that of pure water (Pw0) at the sample's surface temperature. 13 After a certain time, any substance placed in a sealed

Microbiological analysis
Through the fungal survey applied in this study, we were able to detect and identify different fungal genera and species on skin and textile samples taken from mummies from both the storage rooms and the display cases (Fig. 7). Interestingly, the number of   (Fig. 7). These differences become even more apparent when we take a closer look at the functional properties of the "material-specific" fungal species detected. Fungi were only detected on the textile/plant material. 19 For example, while sampling a grass mat using contact plates, we only observed the presence of one fungus, Aspergillus welwitschiae, which is known to be involved in the breakdown of fibrous plant material such as sisal 20 (Fig. 7). Taken together, almost all the fungi detected in the textile material are commonly found saprophytes involved in degrading plant remains. In contrast, the soft tissue harboured unique fungal species such as Alternaria infectoria, a saprophytic fungus known to thrive on skin tissue. 21 In addition, we detected several Penicillium species (e.g. Penicillium chrysogenum) on the soft tissues, known for their proteolytic potential. 22 There is therefore a clear indication of the presence of material-specific fungal communities.

Final considerations
In sum, our results indicate a still present biodegradational potential in the form of tissue-specific fungal communities (spores and mycelia), which could become a biodegradative risk as soon as the environmental conditions change, for example, at water activity levels above 0.65 (aw), which promote fungal growth. 23 It is therefore of the utmost importance to keep the water activity levels of these unique cultural assets under constant control.

Acknowledgements
The authors wish to thank their partners for their valuable collaboration, without which it would not have been possible to complete this study project: