Study on fungi in archives of offices, with a particular focus on Stachybotrys chartarum

Uncovering the microbial diversity of Czech Republic archives: A study of metabolically active airborne microbes

Despite the diligent efforts of libraries, archives, and similar institutions to preserve cultural monuments, biodeterioration continues to pose a significant threat to these objects. One of the main sources of microorganisms responsible for the biodeterioration process is the presence of airborne microorganisms. Therefore, this research aims to monitor and compare outcomes of both culture-dependent (utilising various cultivation strategies) and culture-independent approaches (RNA-based sequencing) to identifying metabolically active airborne microorganisms in archives in the Czech Republic. Through this study, several species that have the potential to pose risks to both cultural heritage objects and the health of institution employees were found. Additionally, the efficacy of different cultivation media was demonstrated to be varied across archive rooms, highlighting the necessity of employing multiple cultivation media for comprehensive analyses. Of noteworthy importance, the resuscitating-promoting factor (Rpf) proved to be a pivotal tool, increasing bacterial culturability by up to 30% when synergistically employed Reasoner's 2A agar (R2A) and R2A + Rpf media. Next, the study emphasises the importance of integrating both culture-dependent and culture-independent approaches. The overlap between genera identified by the culture-dependent approach and those identified also by the culture-independent approach varied from 33% to surpassing 94%, with the maximum alignment exceeding 94% in only one case. Our results highlight the importance of actively monitoring and assessing levels of microbial air contamination in archives to prevent further deterioration of cultural heritage objects and to promote improved conditions for employees in archives and similar institutions.

Occupational exposure to fungi on recyclable paper pots and growing media and associated health effects - A review of the literature

Different types of pots and growing and casing media, including biodegradable materials, are used for plant and mushroom production. The fungus Peziza ostracoderma has gained attention for its visible growth on growing media for plants and casing media for mushrooms. Through a review of the literature we aim to evaluate whether exposure to fungi from recyclable pots and different growing and casing media occurs and causes occupational health effects. Based on the published papers, specific fungal species were not related to a specific medium. Thus P. ostracoderma has been found on paper pots, peat, sterilized soil, vermiculite, and rockwool with plants, and on peat, pumice, and paper casing for mushrooms. It has been found in high concentrations in the air in mushroom farms. Also Acremonium spp., Aspergillus niger, A. fumigatus, Athelia turficola, Aureobasidium pullulans, Chaetomium globosum, Chrysonilia sitophila, Cladosporium spp., Cryptostroma corticale, Lecanicillium aphanocladii, Sporothrix schenckii, Stachybotrys chartarum, and Trichoderma spp. have been found on different types of growing or casing media. Most of the fungi have also been found in the air in greenhouses, but the knowledge about airborne fungal species in mushroom farms is very limited. Eight publications describe cases of health effects associated directly with exposure to fungi from pots or growing or casing media. These include cases of hypersensitivity pneumonitis caused by exposure to: A. fumigatus, A. niger, Au. pullulans, Cr. corticale, P. ostracoderma, and a mixture of fungi growing on different media. Different approaches have been used to avoid growth of saprophytes including: chemical fungicides, the formulation of biodegradable pots and growing media and types of peat. To increase the sustainability of growing media different types of media are tested for their use and with the present study we highlight the importance of also considering the occupational health of the growers who may be exposed to fungi from the media and pots.

One-Step Reinforcement and Deacidification of Paper Documents: Application of Lewis Base—Chitosan Nanoparticle Coatings and Analytical Characterization

To delay acidification and deterioration during natural aging, deacidification and reinforcement of paper manuscripts have been the most important technologies to prolong the life of objects. Herein, a novel approach for the conservation of paper manuscripts is proposed using chitosan nanoparticles as Lewis base that leads to both deacidification and strengthening of paper in one-step. Chitosan nanoparticles were prepared through physical ball grinding method and characterized via scanning electron microscopy (SEM), X-ray diffraction (XRD), laser particle size analyzer (LPSA), Fourier transform infrared spectroscopy (FTIR), and atomic force microscope (AFM). To evaluate the resistance of chitosan nanoparticle coating, the mechanical properties of paper after artificial aging were evaluated using dry heat and hygrothermal accelerated aging methods. The SEM, EDX, and X-ray Photoelectron Spectroscopy (XPS) were used to analyze the interaction mechanism between chitosan and Shuxuan paper. The results show that the coated paper had superior durability with respect to pH, tensile strength, and folding endurance. There was a presence of protonated amines in the form of ammonium salts due to ionic bindings with free H+ in the acidified paper, and the remaining –NH2 could be used as a base reserve. Finally, the resulting coated papers displayed good antibacterial properties.

Indoor damp surfaces harbor molds with clinical significance

Background and Purpose:

Fungal contamination in damp places in buildings has become an increasing problem worldwide. Dampness facilitates the growth of fungi, which can cause adverse effects not only on the buildings but also on their occupants. The aim of this study was to identify indoor mold species in the buildings of Kerman province, Iran.

Materials and Methods:

In this study, 110 samples were obtained from surfaces of damp indoor areas in buildings randomly selected in Kerman province. The identification of fungal species was based on the macroscopic and microscopic characteristics of the isolates, such as colony morphology, hyphae, conidia, and conidiophores, as well as molecular sequence data.

Results:

Based on the results, a total of 218 fungal isolates were obtained. Apart from frequently isolated fungi, such as Alternaria, Aspergillus, and Penicillium, 13 species, including Cladosporium sphaerospermum, Cladosporium herbarum, Cladosporium halotolerans, Engyodontium album, Collariella bostrychodes, Stachybotrys xigazenensis, Ramularia eucalypti, Fusarium merismoides, Fusarium solani, Ochroconis musae, Mucor racemosus, Acremonium zonatum, and Acremonium persicinum were identified, and the selected species were described. Among these 13 species, Cladosporium was the most common species (43%) in indoor surfaces, followed by Ochroconis musae (10.8%) and Engyodontium album (7.4%). To the best of our knowledge, Stachybotrys xigazenensis was reported in the present study for the first time in Iran. In addition, E. album and O. musae were isolated for the first time from indoor surfaces in Iran.

Conclusion:

According to the results, the level of overall fungal richness across indoor surfaces was high. Some of the isolated taxa were clinically significant. It was concluded that the damp residential surfaces were potentially passive collectors of clinically significant molds.

Identification of saprophytic and allergenic fungi in indoor and outdoor environments

The airborne spores of some saprophytic and allergenic fungi such as Aspergillus, Alternaria, and Cladosporium are found throughout the world and exposure to these agents may result in various types of allergic diseases. The aim of this study, therefore, was to investigate the frequency of different saprophytic, allergenic, and pathogenic fungi in indoor and outdoor environments. During a 6-month period, 780 samples were obtained from a number of houses, mosques, parks, public restrooms, grocery stores, laboratories, and hospitals. An open-plate method was applied for air sampling by exposing 90-mm plates containing chloramphenicol/potato dextrose agar and malt extract agar were exposed to air for 30 min. Alternatively, the sampling from surfaces was performed using sterile wet swab and tape-stripe method. All samples were then inoculated in media and incubated at 28 °C for 2-3 weeks. The isolated fungi were purified in order to detect the genus, and if possible, species level of the targeted fungi based on morphological and microscopic features using standard methods. The findings revealed that the dominant indoor and outdoor fungal species were Aspergillus, Penicillium, and Cladosporium whose frequency values were 16.42%, 16.17%, and 14.92% respectively. The lowest frequency was related to Acrophialophora and Madurella (0.25%). More notably, the results for air and surface were similar. It was also found out that the three dominant genera were Aspergillus (16.53%), Penicillium (15.50%), and Cladosporium (11.93%), with Basidiobolus and Acrophialophora having the lowest frequency. It was observed that different environmental spaces have a great bearing on the spreading of such allergic agents, especially in subtropical humid climates.