A method to determine the content of total glutathione (GSHt) was introduced based on high-performance liquid chromatography (HPLC) with dansylation. The minimum detection concentration of GSHt was 0.5 microg/mL and the measurable range 1.0-300 microg/mL. GSHt in yeasts was obtained by hot-water extraction, GSH complete autoxidation to oxidized glutathione (GSSG) in alkaline solution and purification by thin-layer chromatography (TLC). The quantitative determination of GSSG was derived by dansyl chloride at pH 9.5, 60 degrees C for 60 min and assayed by HPLC. GSHt in Saccharomyces cerevisiae is higher than in Candida rugosa and Candida utilis. S. cerevisiae can be chosen as the better target for mutagenesis and industrial scale.