Extraction and characterization of collagen and gelatin from body wall of sea cucumbers stichopus horrens and holothuria arenicola

• Main Authors: Noora Barzkar, Gilan Attaran-Fariman, Ali Taheri, Balu Alagar Venmathi Maran
• Format: Article
• Language: English
• Published: PeerJ, Inc. 2024
• Subjects: Q1-390 Science (General); QP501-801 Animal biochemistry
• Online Access: https://eprints.ums.edu.my/id/eprint/42890/1/FULL%20TEXT.pdf; https://eprints.ums.edu.my/id/eprint/42890/; http://dx.doi.org/10.7717/peerj.18149
• Institution: Universiti Malaysia Sabah

Background: Marine invertebrates, including sponges, molluscs, jellyfish, mussels, and sea cucumbers, are abundant sources of high-quality collagen and offer advantages such as availability, ease of processing, lower inflammatory response, and good metabolic compatibility. Approximately 70% of the total protein in the body wall of sea cucumbers is collagen. Gelatin is a water-soluble protein produced from heat-denatured collagen and has various industrial applications. Methods: Pepsin-solubilized collagen was extracted from the body wall of two sea cucumber Stichopus horrens and Holothuria arenicola, species found in the Oman Sea and characterized with SDS-PAGE and amino acid composition. Then gelatin was extracted from pepsin-solubilized collagen of S. horrens and some rheological properties were measured. Results: Amino acid composition and SDS-PAGE analysis showed that the collagen from both species was type I, with one a1 chain and β chains, with molecular weights of 125 and 250 kDa, respectively. Glycine was the most abundant amino acid in the collagen from both sea cucumber species. The pepsin-soluble collagens from both species had high levels of glycine, proline, alanine, glutamic acid, and hydroxyproline. The gelatin from S. horrens had a melting point of 30 °C and displayed exceptional thermal stability, surpassing that of mammalian gelatin. Its gelling point was 5 °C, like that of cold-water fish gelatin, with a viscosity of 2.065 cp-lower than mammal gelatins. These findings suggested that collagen and gelatin from sea cucumbers could be useful in nutraceutical, pharmaceutical and cosmetic industries.