Diapause Hormone B: Its Selective Extraction and Isolation from the Silkworm, Bombyx mori

Abstract

A selective extraction procedure of the diapause hormone-B (DH-B) from male silkworm adult heads is described. By this new method a highly active extract (1 DH unit in 30_??_60μg) can be obtained easily without chromatographic purification. It was further purified by successive gel permeation chromatographies to give finally pure DH-B having an activity of 1 DH unit in 2 μg.