Air- and dustborne fungi in repositories of the National Archive of the Republic of Cuba

Air mycobiome in the National Library of Greece following relocation to novel premises

The aim of this work was to study the diversity and spatiotemporal fluctuations of airborne fungi in the National Library of Greece after its relocation from the Vallianeio historic building in the center of Athens to entirely new premises at the Stavros Niarchos Foundation Cultural Center, and also to compare the fungal aerosol in between the two sites. The air mycobiota were studied by a volumetric culture-based method, during the year 2019 in order to assess their diversity and abundance and to compare with those previously reported in the historic building. Twenty-eight genera of filamentous fungi were recovered indoors and 17 outdoors, in addition to yeasts registered as a group. The number of fungal genera recovered was almost similar in both premises, whereas seventeen genera indoors were identical, dominated by Penicillium, Cladosporium and Aspergillus. The mean daily fungal concentration was found to be 66 CFU m-3 indoors and 927 CFU m-3 outdoors in the new location vs 293 and 428 CFU m- 3 indoors and 707 and 648 CFU m- 3 outdoors in the previous one. The mean daily concentration indoors was consistently and significantly lower (P < 0.05) in the new building than in the historic one, although it was higher outdoors. The indoor/outdoor ratio for the total fungi was 0.07 in the new vs 0.41 and 0.66 in the previous one and reveals a superior indoor air quality in the new site. Air temperature and occupancy had a statistically significant impact on the concentration of indoor fungi. The remarkably reduced concentration of the mycobiota in the new premises indicated a considerable decline in fungal burden, mainly due to technological excellency of the facility and continuous preventive measures to ensure an enhanced indoor air quality in the National Library of Greece. This case study provides a paradigm about upgrading of indoor air after re-establishment of a facility in another setting.

Variability in Microbial Communities Driven by Particulate Matter on Human Facial Skin

Microbial communities are known to play an important role in maintaining ecological balance and can be used as an indicator for assessing environmental pollution. Numerous studies have revealed that air pollution can alter the structure of microbial communities, which may increase health risks. Nevertheless, the relationships between microbial communities and particulate matter (PM) caused by air pollution in terms of health risk assessment are not well understood. This study aimed to validate the influences of PM chemical compositions on microbial communities and assess the associated health risks. Our results, based on similarity analysis, revealed that the stability structure of the microbial communities had a similarity greater than 73%. In addition, the altered richness and diversity of microbial communities were significantly associated with PM chemical compositions. Volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs) exerted a positive influence on microbial communities in different environmental variables. Additionally, a stronger linear correlation was observed between hydroxyl radicals (·OH) and the richness of microbial communities. All estimated health risks from PM chemical compositions, calculated under different environmental variables, significantly exceeded the acceptable level by a factor of more than 49. Cr and 1,2-Dibromoethane displayed dual adverse effects of non-carcinogenic and carcinogenic risks. Overall, the study provides insights into the fundamental mechanisms of the variability in microbial communities driven by PM, which may support the crucial role of PM chemical compositions in the risk of microorganisms in the atmospheric environment.

New frontiers review of some recent conservation techniques of organic and inorganic archaeological artefacts against microbial deterioration

The information on the advances and technology of some recent conservation methods (2020–2023) of organic and inorganic archaeological objects against microbial deterioration is recorded. An outline of comparative new protective methods for conserving plant-origin organic artefacts {Fibers (manuscripts, textile) and wood}, animal-origin organic artefacts (painting, parchment and mummies) and inorganic stone artefacts were investigated. The work not only contributes to the development of safe revolutionary ways for more efficient safe conservation of items of historical and cultural worth but also serves as a significant diagnostic signature for detecting the sorts of microbial identification and incidents in antiques. Biological technologies (environmentally friendly green biocides) are the most used recent, efficient and safe strategy acceptable as alternatives to stop microbial deterioration and prevent any potential interactions between the biological agent and the artefacts. Also, a synergistic effect of combining natural biocides with mechanical cleaning or chemical treatments was suggested. The recommended exploration techniques should be considered for future applications.

Analysis of the composition of culturable airborne microorganisms in the archaeological excavation protection site of the Nanhai No. 1 Ancient Shipwreck

After the recovery of the ship from the sea on 2007, the Nanhai No. 1 Ancient Shipwreck is currently exposed to the air. Air microorganisms settle on wooden shipwrecks, and they can use wood matrix to grow and multiply, causing biocorrosion and biodegradation. In this study, a systematical survey of the composition of culturable airborne microorganisms was performed at the conservation site of the Nanhai No. 1 Ancient Shipwreck. Airborne microorganisms were collected from seven sites in the preservation Nanhai No. 1 area over five periods. Molecular identification of the culturable microorganisms isolated from the air was done by sequencing both 16S rRNA (bacteria) and ITS (fungi) gene regions. The biodegradability of these strains was evaluated by degradation experiments with cellulose and lignin as substrate. The results showed that the composition of the isolated microbial communities was different in each period, and microbial spatial distribution was dissimilar in the same period. In the recent 2020, the dominant bacterial genus was Acinetobacter, and the dominant fungal genera were Penicillium, Aspergillus, and Cerrena. Acinetobacter spp. can degrade cellulose and lignin. Penicillium spp., Aspergillus spp., and Cerrena spp. degraded cellulose but only Cerrena spp. could utilize lignin. These dominant strains may have a harmful effect on the Nanhai No. 1 Ancient Shipwreck. This study provides data on the airborne microbial community found inside the protective chamber where Nanhai No. 1 Shipereck is placed, which can be used as a reference basis for the future conservation of the ship.