Alcaligenes xylosoxidans subsp. xylosoxidans (SH91) capable of biodegradation of thiodiglycol (TDG) were immobilized in poly(vinyl) alcohol (PVA) cryogels. Cryoimmobilized biocatalyst was formed as spherical granules with a diameter of 0.5 mm; the biomass concentration inside the gel matrix was as high as 10% (w/w). The immobilized cells were capable of rapid degradation of TDG in tap water or potassium phosphate buffer (100 mM, pH 8.0) containing only (NH4)(2)SO4. The immobilized biocatalyst did not show any substrate inhibition up to 200 mM TDG, and retained 100% activity during three months of continuous use in a repeated-batch bioreactor.