Analyses were performed with 150 mg of lyophilized soil. Ergosterol was extracted from soil
by 30 min refluxing in alcoholic base (Gessner et al., 1991) and purified by solid-phase extraction (Gessner and Schmitt, 1996). Final purification and quantification of ergosterol was achieved by highperformance liquid chromatography (HPLC) on a HP series 1050 chromatograph. The system was run with HPLC-grade methanol at a flow rate of 1.5 ml min−1. Ergosterol eluted after 9 min and
was detected at 282 nm; peak identity was checked on the basis
of retention times of commercial ergosterol purchased from Fluka
(98% purity)