Explanation

Crypts of Leiberkuhn or intestinal glands are present in the duodenum and ileum (parts of small intestine only). The secretion of intestinal glands is called intestinal juice or succus entericus. It contains many enzymes-maltase, isomaltase, sucrase, lactase, $\alpha$-dextrinase, enterokinase, aminopeptidase, dipeptidase, nucleotidases, nucleosidases and intestinal lipase.