Enzyme-assisted extraction of proteins from Citrus fruits and prediction of their cultivar using protein profiles obtained by capillary gel electrophoresis

Abstract

The suitability of protein profiles established by capillary gel electrophoresis (CGE) as a tool to differenciate between 11 cultivars of Citrus (orange and tangerine) peel and pulp was evaluated in this work. Before CGE analysis, different extraction buffers (which included enzyme-assisted treatments) were compared. The best results were achieved using 5% (v/v) Celluclast® 1.5L and 5% (v/v) Palatase® 20000 L buffers for Citrus peel and pulp protein extracts, respectively. The resulting protein profiles obtained were used to construct linear discriminant analysis (LDA) models able to distinguish Citrus peel and pulp samples according to their cultivar. In both cases, all samples were correctly classified with an excellent resolution among all classes, which demonstrated that protein patterns are a powerful tool to discriminate Citrus samples coming from different cultivars.