The digestive enzymes of the larva of Utetheisa pulchella Linnaeus (Lepidoptera: Arctidae).

Abstract

Some observations of the secretion of digestive enzymes were made in the fully grown larva of Utetheisa pulchella Linnaeus. - 1. The extracts of the digestive tract show the presence of trypsin, polypeptidases, dipeptidasis, alkaline phosphatase, invertase, amylase, maltase and esterasess. - 2. The salivary gland extracts have invertase, amylase and trypsin-like enzymes. - 3. The maximal activity of trypsin, invertase and amylase occurs at pH 8.0, 6.5 and 9.5 respectively. - 4. The secretion of invertase and amylase is largely localized in the anterior third of the midgut tissue, but some amylase is also secreted from the tissue of the posterior midgut. 5. - Trypsin-like enzyme is almost uniformly secreted from the tissue of the whole midgut. - 6. These enzymes are not present in the tissue of fore- and hidgut.