Abstract
The failure of activity staining of trypsin inhibitors in crude leaf extracts of sweet potatoe varieties including Tainong 27, Tainong 34, and Tainong 57 on a 15% sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gel was prevented by dipping the gels in solutions containing 10–40 mM hydrogen peroxide, 10 mM Tris buffer (pH 7.9) for 30 min before staining.