an essential amino acid,C4H9CH(NH2)COOH,derived from the hydrolysis of protein by pancreatic enzymes during digestion and necessary for optimal growth in infants and children and for the maintenance of nitrogen balance in adults

• 一种重要的氨基酸，C4H9CH（NH2）COOH，由胰酶在消化过程中从蛋白质的水解作用中分离出来，对婴幼儿良好的生长发育及成人保持氮平衡十分必要