OATAO - Open Archive Toulouse Archive Ouverte Open Access Week

Effect of Culture Conditions on Ergosterol as an Indicator of Biomass in the Aquatic Hyphomycetes

Charcosset, Jean-Yves and Chauvet, Eric Effect of Culture Conditions on Ergosterol as an Indicator of Biomass in the Aquatic Hyphomycetes. (2001) Applied and Environmental Microbiology, 67 (5). 2051-2055. ISSN 0099-2240

(Document in English)

PDF (Author's version) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader

Official URL: http://dx.doi.org/10.1128/AEM.67.5.2051-2055.2001


Ergosterol is a membrane component specific to fungi that can be used to estimate fungal biomass using appropriate factors of conversion. Our objectives were to determine the limits of use of ergosterol content as a measure of biomass for aquatic hyphomycetes, and to evaluate a previously established ergosterol-to-biomass conversion factor. We varied inoculum quality, growth medium, and degree of shaking of four aquatic hyphomycete species. In cultures inoculated with homogenized mycelium, we found a significant effect of shaking condition and culture age on ergosterol content. In liquid cultures with defined medium, ergosterol content reached 10 to 11 mg/mg of mycelium (dry mass) and varied by factors of 2.2 during exponential growth and 1.3 during stationary phase. The increase in ergosterol content during exponential phase could be attributed, at least in part, to rapid depletion of glucose. Oxygen availability to internal hyphae within the mycelial mass is also responsible for the differences found between culture conditions. Ergosterol concentration ranged from 0.8 to 1.6 mg/mg in static cultures inoculated with agar plugs. Ergosterol content varied by a factor of 4 in two media of different richnesses. For different combinations of these parameters, strong (r2 5 0.83 to 0.98) and highly significant (P ! 0.001) linear relationships between ergosterol and mycelial dry mass (up to 110 mg) were observed. Overall, the ergosterol content varied by a factor of 14 (0.8 to 11 mg/g). These results suggest that care must be taken when the ergosterol content is used to compare data generated in different field environments.

Item Type:Article
Additional Information:Thanks to the American Society for Microbiology. The original PDF of the article can be found at Applied and Environmental Microbiology website : http://aem.asm.org/cgi/content/abstract/67/5/2051
HAL Id:hal-01338027
Audience (journal):International peer-reviewed journal
Uncontrolled Keywords:
Institution:Université de Toulouse > Université Toulouse III - Paul Sabatier - UT3 (FRANCE)
French research institutions > Centre National de la Recherche Scientifique - CNRS (FRANCE)
Laboratory name:
Deposited On:04 Jun 2010 15:11

Repository Staff Only: item control page