Identification of four low molecular and water-soluble proteins from grape (Vitis vinifera L.) seeds

P>Profiles of soluble proteins isolated from mature seeds of grape (Vitis vinifera L.) pomace were studied using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) coupled with matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF-MS). Two-dimensional gels stained with Coomassie brilliant blue revealed more than fifty protein spots. Four abundant protein spots showing low molecular weight (Mr) and wide isoelectric point (pI) were analysed by MALDI-TOF-MS, resulting in their identification. Taken together, these results suggest that identified proteins may be linked to seed development and metabolism, but more instructive is that they have some potential functions for future food application. These results provide some insights into conversion of grape processing wastes into useful products or even as raw material for other industries.