>99% [HPLC]. Free 4MU < 200ppm.
Substrate for alpha-glucosidase: R.Gossrau, Histochemistry, 52, 187 (1977). In Pompe's disease: H. Galjaard et al., Clin. Chim. Acta, 49, 361 (1973).
Enzymatic activities in traps of four aquatic species of the carnivorous genus Utricularia.