THE ISOLATION AND PRELIMINARY FRACTIONATION OF PROTEINS FROM DORMANT AND GROWING POTATO TUBERS

Abstract

Freeze-dried potato tuber slices were ground in a Wiley mill, extracted with buffer and precipitated with (NH4)2SO4. The precipitate was resuspended and dialyzed. The crude protein so obtained comprised about 2% of the potato powder, accounted for at least 2/3 of the total protein, and had a N content of about 12.5%. Its water-soluble content, and to an even greater degree that fraction of it precipitated at pH 5.3, was higher in tuber halves sprouted at room temp. than in the corresponding un-sprouted halves kept at 0-5[degree]C.