Studies on Biological Activities of Melanin from Marine Animals. II. Purification of Melanin from Octopus vulgaris CUVIER and Its Inhibitory Activity on Gastric Juice Secretion in Rats

抄録

Octopus melanin obtained from ink bags of Octopus vulgaris CUVIER was found to inhibit gastric secretion in rats in the same way as that from Ommastrephes bartrami LESUEL. The molecular weight of this melanin fraction (which has an indole skeleton) was estimated to be over 200000 by gel filtration on Sephadex G-200, and the Octopus melanin fraction (Fr. OM) released several kinds of proteins in the presence of SDS. The chemical composition of Fr. OM was melanin pigment 79%, protein 17.5% and sugar 1.7%, so Fr. OM was considered to be a melanoprotein. Fr. OM significantly reduced gastric secretion in rats at the dose of 1 mg/kg, i.p., and also prevented both ulcer formation in pylorusligated rats and aspirin-induced ulcer.