Seasonal variation of airborne fungi of the Tiantishan Grottoes andWestern Xia Museum,Wuwei,China

In this study,a systematic survey of cultural airborne fungi was carried out in the occurrence environments of wall paintings that are preserved in the Tiantishan Grottoes and the Western Xia Museum,China.A bio-aerosol sampler was used for sampling in four seasons in 2016.Culture-dependent and-independent methods were taken to acquire airborne fungal concentration and purified strains;by the extraction of genomic DNA,amplification of fungal ITS rRNA gene region,sequencing,and phylogenetic analysis,thereafter the fungal community composition and distribution characteristics of different study sites were clarified.We disclosure the main environmental factors which may be responsible for dynamic changes of airborne fungi at the sampling sites.The concentration of cultural airborne fungi was in a range from 13 to 1,576 CFU/m^(3),no significant difference between the two sites at the Tiantishan Grottoes,with obvious characteristics of seasonal variation,in winter and spring were higher than in summer and autumn.Also,there was a significant difference in fungal concentration between the inside and outside of the Western Xia Museum,the outside of the museum was far more than the inside of the museum in the four seasons,particularly in the winter.Eight fungal genera were detected,including Cladosporium,Penicillium,Alternaria,and Filobasidium as the dominant groups.The airborne fungal community structures of the Tiantishan Grottoes show a distinct characteristic of seasonal variation and spatial distribution.Relative humidity,temperature and seasonal rainfall influence airborne fungal distribution.Some of the isolated strains have the potential to cause biodeterioration of ancient wall paintings.This study provides supporting information for the pre-warning conservation of cultural relics that are preserved at local sites and inside museums.

Fungal contaminations of indoor and outdoor air of buildings of the University of Cape Coast,Ghana

The presence of microscopic spores in the air affects the quality of air inhaled by animals including humans.Microbial contamination of air impacts the well-being of occupants of an indoor environment,sometimes with dire consequences.The study investigated fungal contaminations of indoor and outdoor air of the Hospital,Library and Senior Common Room(SCR)of the University of Cape Coast,Ghana.Indoor and outdoor air was sampled using the Koch’s sedimentation method.Colony forming units per cubic meter of air(cfu/m^(3))were determined with the Omeliansky formula.The isolated fungi were identified based on morphological and growth characteristics.For indoor air,the least colony counts were recorded in the SCR for both morning and afternoon samples,whilst the Hospital air had the highest colony counts.For outdoor air,the colony counts were lower in SCR and the Library for both morning and afternoon samples compared to the Hospital.The results further indicated that indoor concentrations of fungi,for morning and afternoon,ranged between 4.0x10^(4) and 2.1x10^(5) cfu/m^(3),whereas outdoor concentrations of fungi ranged between 1.1x105 and 3.0x10^(5) cfu/m^(3),revealing an overall higher levels of contamination of outdoor air than indoor air at all the three buildings.Consequently,estimated indoor/outdoor(I/O)concentration ratios of fungi revealed an exogenous source of indoor contaminations at all the three buildings sampled.Fungi isolated from indoor and outdoor air were of the genera Aspergillus,Curvularia,Cylindrocarpon,Fusarium,Mucor,Neurospora,Penicillium and Rhodotorula.We conclude that indoor and outdoor air of the buildings sampled were contaminated with airborne fungi;however,based on estimated I/O ratios,the indoor ambient conditions of the buildings were good.The implication of findings of this study is that the presence of airborne fungal contaminants of indoor and outdoor workplace environment may pose serious occupational health consequences,hence low productivity.