A preliminary investigation on airborne fungi of pedestrian underpasses

摘要

Pedestrian underpasses are the unique environment where air transaction with outdoor is complicated, inducing interest to study the air quality for the presence of microbes. Thus, the study on the presence of airborne fungi from 11 different underpasses in Chennai city was conducted. The airborne fungi was monitored by exposing potato dextrose agar strips in reuter centrifugal sampler (RCS). A total of 1735 colonies were isolated from underpasses and the control site recorded only 1255 colonies. Total average colony forming unit of underpasses and control site was 157.7 CFU/m(3) of air and 114.09 CFU/m(3) of air, respectively. Altogether 22 species classified in 16 genera were isolated from both the environments. Of which 21 species belonging to 16 genera were isolated from underpasses whereas the control site yielded 15 species belonging to 12 genera. The isolated species were categorized into three species belonging to Zygomycota, 2 species to Ascomycota and the remaining to Mitosporic fungi. The air sample in the underpass is dominated by the presence of the fungi, Aspergillus flavus, Curvularia lunata and A.niger, whereas the control is dominated by Cladosporium cladosporioides, Aspergillus niger and A. flavus. The study proves the underpasses are a favorite niche for the proliferation of fungal propagules and proper maintenance of underpass is recommended.