A comparison of several media types and basic techniques used to assess outdoor airborne fungi in Melbourne, Australia

Abstract

Despite the recent increase in interest in indoor air quality regarding mould, there is no universally accepted standard media for the detection of airborne fungi, nor verification of many commonly used techniques. Commonly used media including malt-extract agar (MEA), Sabouraud dextrose agar (Sab), potato dextrose agar (PDA) with and without antibiotics chloramphenicol & gentamycin (CG) were compared for their suitability in detecting a range of airborne fungi by collecting 150 L outdoor air on a number of different days and seasons via an Anderson 400-hole sampler in suburban Melbourne, Australia. There was relatively little variation in mean numbers of colony forming units (CFU) and types of fungi recovered between MEA, PDA, Sab media groups relative to variation within each group. There was a significant difference between Sab, Dichloran-18% glycerol (DG18) and V8® Original juice agar media, however. Antibiotics reliably prevented the growth of bacteria that typically interfered with the growth and appearance of fungal colonies. There was no significant evidence for a growth enhancing factor from potato, mineral supplements or various vegetable juices. Differing glucose concentrations had modest effects, showing a vague ideal at 2%-4% with peptone. Sanitisation of the aluminium Andersen 400-hole sampler top-plate by flame is possible, but not strictly required nor advisable. The use of SabCG as a standard medium was generally supported.

Loading Rates of Dust and Bioburden in Dwellings in an Inland City of Southern Europe

“…It was possible to obtain information on the housing typologies and characteristics that most influence microbial contamination, including azole resistance. The influence of all these variables was previously studied [54][55][56][57][58][59][60][61][62][63][64][65][66][67][68][69][70]. In the present study, results correlated with several physical variables.…”

“…As for MEA media, they have been extensively used for decades due to its low cost and high availability of malt extract. However, for the wide range of fungi growing in microenvironments such as damp cardboard or carpets in water damaged buildings, the use of maltose as substrate is not likely given its typical absence in those ecological niches [62].…”

Aspergillus Section Fumigati in Firefighter Headquarters

“…counts, and Aspergillus section Fumigati with SDA and ITR+VOR media, compared to MEA or DG18, suggest Sabouraud is a more suitable media for the recovery of fungi and Aspergillus sp. The use of Sabouraud as a standard medium to assess outdoor airborne fungi by air sampling was generally supported in a recent study on media comparison [45], and has also been supported in clinical applications [46]. However, Saboraud enhanced Chrysonilia sitophila in other performed assessments [9,18].…”

Exploring the Diversity and Aromatic Hydrocarbon Degrading Potential of Epiphytic Fungi on Hornbeams from Chronically Polluted Areas

“…In order to isolate epiphytic fungi, we plated pure and 1/10 diluted leaf wash suspensions onto different types of agar solid media containing different nutrients and at different concentrations [21]. Malt Extract Agar [30,31] and Czapek dox at pH = 5 [32] were chosen because both these media are recommended for the general cultivation of fungi from a wide range of environmental niches. Furthermore, pure and 1/10 diluted leaf wash suspensions were also screened on 869 rich media plates at pH = 7 [21], 1/10 LB plates pH = 7 [33], and from minimal medium YMAb284 plates pH = 7 [21].…”