Preparation of a novel chitosan-based biosorbent cross-linked with phenethylamine for adsorption of aromatic amino acids

Rice protein was successively hydrolyzed by rice protein hydrolysis special enzyme, chymotrypsin and carboxypeptidases A. Then a novel chitosan-based biosorbent cross-linked with phenethylamine (PMCCR) was synthesized and firstly used for adsorption of aromatic amino acids (AAA) from rice protein enzymatic hydrolysates (RPEH). The characterizations of PMCCR indicated that phenethylamine was successfully cross-linked with chitosan, and the particle size of PMCCR was 500-1000 μm with pore diameter of 50-100 μm. Furthermore, PMCCR showed an efficient adsorption property to AAA in RPEH, reaching equilibrium at 80 min of 28.54 mg/g, and the adsorption data could be well fitted with Freundlich isotherm model. The amino acids analysis of RPEH after adsorption (RPEHA) showed that AAA in RPEH was basically adsorbed by PMCCR, with a Fisher's ratio of 21.2. Overall, this novel chitosan-based biosorbent cross-linked with phenethylamine might be highly promising to facilitate efficient adsorption of aromatic amino acids and prepare protein enzymatic hydrolysates with a high Fischer's ratio.