Abstract: This study aimed at the chelation technology of sodium selenite and compound L-amino acid from soybean meal by enzymatic hydrolysis. The results showed that optimum enzymatic hydrolysis condition for compound L-amino acid are as follows:ratio of material to liquid 1:25(W/V) ,pH 8.5 and hydrolysis time 4 h of 10%(addition amount) trypsin and 8%(addition amount) papain respectively. Under these conditions the hydrolysis rate is 39.61%. The optimum chelation conditions for compound L-amino acid and sodium selenite are determined through orthogonal test as follows:chelation temperature 80 ℃,pH 9.0 and molar ratio between them 2:1. The chelation ratio is 43.28% under these conditions. Finally the chelation of complex L-amino acid and sodium selenite is confirmed by infrared spectroscopy.

Key words: compound L-amino acid, sodium selenite, chelation ..