Effects of Temperature on the FT NIR Raman Spectra of Fish Skin Collagen

The development of regenerative medicine turns attention toward native collagen as a biocompatible material. Particularly interesting is fish skin collagen, which is relatively easy to extract comparing mammalian tissues and free of some pathogens that are dangerous to humans. The paper presents results of IR Raman spectroscopy studies of silver carp (Hypophthalmichthys molitrix) skin collagen. As collagen properties result from its structure and conformation, both sensitive to temperature, FT NIR Raman spectroscopy is an excellent tool to characterize the molecular structure of fish skin collagen, particularly in temperature range typical for the manufacturing processes of biomedical products. Therefore, the Raman spectra were recorded in a temperature range of 300 to 403 K. The analysis of Raman spectra of prepared collagen films, particularly in the range of the bands related to amide I and amide III entities, showed a high content of α-helix and α-helix type molecular organization in fish skin collagen. Additionally, the secondary structure of the studied fish skin collagen is stable up to ~358 K. Heating to 403 K leads to irreversible changes in the molecular structure of fish skin collagen. It was found that the Raman spectrum of fish skin collagen preheated in this manner becomes similar to the spectrum of the collagen obtained from bovine Achilles tendon, whose secondary structure does not change up to 403 K.

Anti-Salmonella Activity and Peptidomic Profiling of Peptide Fractions Produced from Sturgeon Fish Skin Collagen (Huso huso) Using Commercial Enzymes

This study investigated peptide fractions from fish skin collagen for antibacterial activity against Escherichia coli and Salmonella strains. The collagen was hydrolyzed with six commercial proteases, including trypsin, Alcalase, Neutrase, Flavourzyme, pepsin and papain. Hydrolyzed samples obtained with trypsin and Alcalase had the largest number of small peptides (molecular weight < 10 kDa), while the hydrolysate produced with papain showed the lowest degree of hydrolysis and highest number of large peptides. Four hydrolysates were found to inhibit the growth of the Gram-negative bacteria, with papain hydrolysate showing the best activity against E. coli, and Neutrase and papain hydrolysates showing the best activity against S. abony; hydrolysates produced with trypsin and pepsin did not show detectable antibacterial activity. After acetone fractionation of the latter hydrolysates, the peptide fractions demonstrated enhanced dose-dependent inhibition of the growth (colony-forming units) of four Salmonella strains, including S. abony (NCTC 6017), S. typhimurium (ATCC 13311), S. typhimurium (ATCC 14028) and S. chol (ATCC 10708). Shotgun peptidomics analysis of the acetone fractions of Neutrase and papain hydrolysates resulted in the identification of 71 and 103 peptides, respectively, with chain lengths of 6–22 and 6–24, respectively. This work provided an array of peptide sequences from fish skin collagen for pharmacophore identification, structure–activity relationship studies, and further investigation as food-based antibacterial agents against pathogenic microorganisms.

Collagen Based Materials in Cosmetic Applications: A Review

This review provides a report on properties and recent advances in the application of collagen in cosmetics. Collagen is a structural protein found in animal organisms where it provides for the fundamental structural support. Most commonly it is extracted from mammalian and fish skin. Collagen has attracted significant academic interest as well as the attention of the cosmetic industry due to its interesting properties that include being a natural humectant and moisturizer for the skin. This review paper covers the biosynthesis of collagen, the sources of collagen used in the cosmetic industry, and the role played by this protein in cosmetics. Future aspects regarding applications of collagen-based materials in cosmetics have also been mentioned.

ISOLATION AND CHARACTERIZATION COLLAGEN OF PATIN FISH SKIN (Pangasius Sp.)

Objective: This study aims to isolate and characterize the collagen isolated from the skin of patin fish.Method: Collagen isolation consisted of three steps, namely deproteinization process using NaOH solution concentration of 0,05 M and long soaking time for 3x24 hours; immersion in CH3COOH solution with a concentration of 0,05 M and long soaking time 3x24 hours; Furthermore, collagen was extracted with water at 40°C for 2 hours. The isolated collagen was tested for characteristics including chemical and physical properties compared to commercial collagen.Results: Chemical characteristics of collagen isolated from patin fish skin isolation compared to commercial collagen, respectively: 6,55% and 6,68% water content; ash content of 0,19% and 0,18%; protein content 93,63% and 97,42% and fat content 0,41% and 0,30%; The metal content in the collagen isolated from the skin of patin fish and commercial collagen is below the threshold (Pb); 0,5 mg/kg. Amino acid test results from patin fish skin collagen obtained glycine (234381,88 mg/kg), proline (109404,17 mg/kg), alanine (83988,79 mg/kg), arginine (80918,44 mg/kg) and glutamate (87315,88 mg/kg). The physical characteristics of the patin fish skin collagen showed the presence of amide group A (3286,7cm-1), amide B (2947,23cm-1), amide I (1651,07cm-1), amide II (1450,47cm-1), and amide III (1246,02 cm-1).Conclusion: Patin fish skin can be isolated into collagen that meets the quality requirements of collagen as a cosmetic preparation.