Collagen in the Tissues of Squid Illex Argentinus and Loligo Patagonica - Contents and Solubility

Collagen was isolated from the skin, connective tissue sheets, and mantle muscle of squid Illex argentinus and Loligo patagonica, by extracting all soluble noncollagenous material. The tissues and the collagen isolates were characterized by determining the total nitrogen, hydroxyproline, and solubility. The contents of hydroxyproline in the collagen isolate of skin, membranes, and muscle of Illex were 5.3, 8.0, and 4.4% dry matter and of Loligo 6.1, 7.4, and 4.9%, respectively. The collagen contents in these tissues were in Illex 4.9, 7.8, and 1.0; in Loligo 3.4, 4.9, and 0.3%, respectively, in the wet material. Collagen preparations obtained from the skin, membranes, and mantle muscle of Loligo yielded, respectively, 9%, 4%, and 8% collagen soluble in citrate buffer. For Illex squid the solubilities were 41%, 6%, and 21%, respectively.