Electrophoretic characterization, amino acid composition and solubility properties of Macauba (Acrocomia aculeata L.) kernel globulins

Abstract

Macauba palm (Acrocomia aculeata L.) fruits are emerging sources to produce high-quality oils from pulp and kernels. Yet, the protein-rich press cake from the kernels remains underutilized, mainly due to lacking knowledge of protein composition and properties. Therefore, our aim was to characterize the main protein fractions of Macauba kernels. The globulins were the major protein fraction (58.5% of storage proteins), which were further separated into 11 S and 7 S globulins. The subunits of both globulins presented heterogeneity in isoelectric point (5.3–8.3), revealing genetic polymorphism. The 7 S globulins were soluble at low ionic strength (0.1 mol/L), whereas the 11 S globulins required higher salt concentration (0.50–0.75 mol/L) for solubilization, independent on selected salt types. Both globulins were rich in essential amino acids, especially methionine and cysteine, making Macauba kernel proteins a valuable source to complement diets based on pulses and oilseeds.