Fish collagen stabilization by phenolic compounds and enzymes for cosmetic applications
Tutor / director / evaluatorTzanov, Tzanko
Document typeBachelor thesis
Rights accessRestricted access - author's decision
Fish industry generates a large biomass of waste that is generally discarded in spite of the potential added value of its components. Enzyme-aided and biomechanical modification steps were explored for fish gelatin in order to obtain a biomaterial suitable for exploitation in skin care applications. The experimental strategies were focused on the use of biocatalysts such as laccase, tyrosinase and transglutaminase as promoters of gelatin cross-linking and stabilization for cosmetic uses. Natural phenolic compounds such as gallic acid, tannic acid and ferulic acid were enzymatically grafted on gelatin for improved structural stability, anti-oxidant and antimicrobial activity. In parallel, chemical cross-linkers 1-ethyl3-(3-dimethylaminopropyl) carbodiimide (EDAC) and N-hydroxysuccinimide (NHS) were applied for gelatin modification. Due to the low molecular weight and the high degree of hydrolysis of the gelatin impeding its transformation into tridimensional solid matrices, a novel approach combining ultrasound, enzymes and natural phenolics was used for the generation of fish gelatin nanoparticles. The simultaneous enzymatic-sonochemical approach provided nanospheres of acceptable particle size distribution and low polidispersity. The selection of a suitable oil phase, cross-linking enzyme and the addition of antioxidant phenolics during sonication renders the fish gelatin nanoparticles potential bioactive carriers in skin care formulations.