A rapid method to extract ergosterol from soil by physical disruption

A physical disruption method was developed to extract ergosterol from soil samples. The optimised procedure was to extract 4 g of moist soil with 6 ml of methanol by shaking for 1 h at 320 rpm in the presence of 4 g of glass beads. Approximately 102% of the spiked pure ergosterol (1, 2 and 30 mug g( -1) soil) was recovered from nine agricultural soils using this method. As a biomarker of fungal biomass, the ratio of ergosterol content to microbial biomass in soil increased with the decreasing of soil pH, implying that ac idic soil environment favoured fungi rather than bacteria. Results from thi s study indicate that the physical disruption method is a potentially promi sing method for ergosterol extraction in soil. (C) 2001 Elsevier Science B. V. All rights reserved.