The effect of incubation temperature and growth media on index microbial fungi of indoor air in a hospital building in Shiraz, Iran

Abstract

This study aimed to consider the effects of incubation temperature (15, 25, and 37°C) and the type of growth media on fungal index microbial airborne (IMA) in a hospital building. Because there weren't any integrated guidelines for these variables, the results weren't comparable. Moreover, some studies have investigated the effects of ambient temperature and other factors by the active sampling method. Therefore, we tried to indicate the difference between use of several media and incubation temperature by passive method. Sampling was taken by an open plate during (1hr, 1 m above the ground). Results were shown that IMA was 112–552 CFU/m2/hr., while its highest level was detected in the dialysis ward at 15°C. The predominant fungal species were A.niger and Cladosporium. Besides, the distribution of IMA in indoor air of the hospital was verified base on the Fourier model (R2 = 0.41 and RMSE = 81.65). Moreover, there were significant differences between IMA at various temperatures (p < 0.05). The estimated IMA on the estimated IMA on specific medium was more than that of the general medium. Moreover, the high correlation was observed for both media at 15, 37°C and the growth coefficients of fungi were approximately similar (k = 11). But, it was significant in both media at 25°C (p < 0.05). In brief, incubation temperatures and growth media were effective on fungal IMA, especially mesophilic species in the indoor air of the hospital. Therefore, it had better pay attention to growth media and conditions such as incubation temperature for fungal monitoring in hospitals.