著者對於前報1)報告亞硫酸鹽對消化酵素之影響，尤其對人唾液amylase有顯著之阻害作用等。本報於in vitro將亞硫酸鹽對唾液amylase之阻害性狀詳於檢討外，於in vitro在各種不同之給與方式下亞硫酸鹽對白鼠血清amylase之影響亦加於研討。 Sulfite inhibited a-amylase activity of saliva, Asp. Fumigatus. Hen serum and mouse serum. Addition of sulfite to the enzymatic reaction system had no effect on the amylase activity. Pre-incubation time was necessary for inhibition of salivary amylase with sulfite. The enzyme inhibited with sulfite was reactivated by addition of an activator such as NaC1 and the enzyne activated with NaC1 was inhibited by the addition of inhibior such as sulfite. With the addition of hydroquinone inhibition of enzyme with sulfite stopped. Immunlogical reaction between antisalivary amylase serum and sulfite-eneyme or native enzyme had no effect on the quantitative precipitin and agar diffusion. Administration of sulfite had no effect on blood amylase activity under sevwral in vivo conditions.