Collagen from diamondback squid (Thysanoteuthis rhombus) outer skin

Area of Science:

• Biochemistry
• Marine Biology
• Biomaterials Science

Background:

• Collagen is a vital structural protein in mammals, primarily sourced from bovine and porcine tissues.
• Concerns regarding Bovine Spongiform Encephalopathy (BSE) and other land-animal diseases necessitate alternative collagen sources.
• Aquatic organisms, including fish and cephalopods, are increasingly explored for their collagen potential.

Purpose of the Study:

• To isolate and characterize collagen from the outer skin of the diamondback squid (Todarodes pacificus).
• To evaluate the potential of diamondback squid skin as a viable alternative source for collagen extraction.
• To compare the properties of squid collagen with those of mammalian collagen.

Main Methods:

• Acid-solubilization and pepsin-solubilization techniques were employed to extract collagen from diamondback squid outer skin.
• Yields of extracted collagen were determined on a dry weight basis.
• Characterization included analysis of collagen chain composition, peptide fragment patterns, denaturation temperature, and amino acid composition.

Main Results:

• Pepsin-solubilized collagen yielded approximately 35.6%, significantly higher than acid-solubilized collagen (1.3%).
• Pepsin-solubilized collagen was identified as a heterotrimer (ala2a3) with distinct peptide fragment patterns compared to porcine collagen.
• The denaturation temperature of squid collagen was 27.5°C, approximately 10°C lower than porcine collagen, with amino acid composition similar to cuttlefish collagen.

Conclusions:

• Diamondback squid outer skin is a rich source of pepsin-solubilized collagen.
• The extracted collagen exhibits properties that suggest its potential as an alternative to bovine and porcine collagen.
• Aquatic collagen sources, like that from diamondback squid, are gaining importance in cosmetic and medical fields due to safety concerns with land-animal derived collagen.