Identification of saprophytic and allergenic fungi in indoor and outdoor environments

Abstract

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.

Contribution of Visible Surface Mold to Airborne Fungal Concentration as Assessed by Digital Image Quantification

“…For surface sampling, we collected data only from residential environments, but the most predominant fungal genera were also found on other indoor environmental surfaces, including those in green groceries, butcheries, houses, public restrooms, and laboratories [ 19 ]. Although commonly found surface fungi, including Cladosporium , Penicillium , and Aspergillus [ 19 , 20 ], are also frequently found in indoor air, fewer fungal genera were observed on the surface than in the air. Most surface sampling was only conducted for qualitative or semiquantitative analysis (no surface area available) for the identification of fungal genera.…”

“…Taking into account the I/O ratios, higher fungal concentrations in outdoor air than in indoor air may reveal an exogenous source of indoor contamination. Cladosporium is a well-known outdoor genus with relatively constant concentrations year-round [ 7 , 8 , 16 , 19 ]. In addition, Cladosporium , Aspergillus , and Fusarium have been found to attach to the surfaces of plant leaves and may produce spores that float into the air [ 30 ].…”

Molecular, physiological, and biochemical characterization of extracellular lipase production by Aspergillus niger using submerged fermentation

“…The seeds were incubated in Tween 80 agar as described by Malekabadia, Badoei-dalfarda & Karamia (2018) for 7 days at 27 °C. Then samples of grown fungi were purified on potato dextrose medium according to the method described by Ziaee, Zia & Goli (2018) and incubated for 5 days for further examination.…”

Comparison of Two Techniques for the Detection of Environmental Fungi in a University Campus

“…However, they do not usually cause complications in individuals with a healthy immune system. Immunocompromised individuals, such as those undergoing chemotherapy or organ transplantation, suffering from leukemias, or diagnosed with HIV, often suffer from infections mediated by these microorganisms, which have the potential to cause serious and fatal diseases [55][56][57]. In a clinical context, a patient on a hospital bed could acquire a nosocomial infection by fungi or other microorganisms.…”