Serine Proteinase Inhibitor from Wax Gourd (Benincasa hispida[Thunb] Cogn.) Seeds

Two squash family protease inhibitors were obtained from wax gourd (Benicasa hispida [Thunb] Cogn.). Even though they were distinctly separated by reversed-phase chromatography, the amino acid sequences of two inhibitors were identical. Both inhibitors were converted into each other, perhaps due to cis-trans isomerization of characteristic Pro in the C-terminal region.