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2008 Dec;9(12):2357-65. Epub 2008 Nov 26.

Growth and Mycotoxin Production by Chaetomium globosum Is Favored in a Neutral

pH.

Fogle MR, DR, Jumper CA, Straus DC.

Department of Microbiology and Immunology, Texas Tech University Health Sciences

Center 3601 4th Street Mail stop 6591 Lubbock, TX 79430, USA.

Chaetomium globosum is frequently isolated in water-damaged buildings and

produces two mycotoxins called chaetoglobosins A and C when cultured on building

material. In this study, the influence of ambient pH on the growth of C.

globosum was examined on an artificial medium. This fungus was capable of growth

on potato dextrose agar ranging in pH from 4.3 to 9.4 with optimal growth and

chaetoglobosin C production occurring at a neutral pH. In addition, our results

show that sporulation is favored in an acidic environment.

PMID: 19330080 [PubMed - in process]

http://www.ncbi.nlm.nih.gov/pubmed/19330080?ordinalpos=1 & itool=EntrezSystem2.PEn\

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2009 Jan 1;407(2):806-14. Epub 2008 Nov 13.

Size-fractionated (1-->3)-beta-D-glucan concentrations aerosolized from

different moldy building materials.

Seo SC, Reponen T, Levin L, Grinshpun SA.

Center for Health-Related Aerosol Studies, Department of Environmental Health,

University of Cincinnati, Cincinnati, OH 45267-0056, USA.

Release of submicrometer-sized fungal fragments (<1.0 microm) was discovered in

earlier studies, which investigated the aerosolization of spores from moldy

surfaces. However, the contribution of fungal fragments to total mold exposure

is poorly characterized. The purpose of this study was to investigate the

size-fractionated concentrations of particulate (1-->3)-beta-D-glucan and

numbers of particles aerosolized from the surface of artificially

mold-contaminated materials using a novel sampling methodology. Aspergillus

versicolor and Stachybotrys chartarum were grown on malt extract agar and

building materials (ceiling tiles and gypsum board) for one to six months.

Fungal particles released from these materials were collected size-selectively

by a newly developed Fragment Sampling System, and (1-->3)-beta-D-glucan in air

samples was analyzed by Limulus Amebocyte lysate (LAL) assay. The concentrations

of (1-->3)-beta-D-glucan varied from 0.4x10(0) to 9.8x10(2) ng m(-3) in the

fragment size and from 1.0x10(1) to 4.7x10(4) ng m(-3) in the spore size range.

Numbers of submicrometer-sized particles aerosolized from 6-month old cultures

were always significantly higher that those from 1-month old (P<0.001). This can

be attributed to increased dryness on the surface of material samples and an

increase in fungal biomass over time. The average fragment to spore ratios both

in particle numbers and (1-->3)-beta-D-glucan mass were higher for S. chartarum

than for A. versicolor. The results indicate that long-term mold damage in

buildings may lead to increased contribution of fragments to the total mold

exposure. Therefore, the health impact of these particles may be even greater

than that of spores, considering the strong association between numbers of fine

particles and adverse health effects reported in other studies. Furthermore, the

contribution of fragments may vary between species and appears to be higher for

S. chartarum than for A. versicolor.

PMID: 19012949 [PubMed - indexed for MEDLINE

http://www.ncbi.nlm.nih.gov/pubmed/19012949?ordinalpos=1 & itool=PPMCLayout.PPMCAp\

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