Polyphenol oxidase mediated (-)-epigallocatechin gallate stabilized protein in body wall of Apostichopus japonicus: Characteristics and structure

Heat treatment is the most common processing method in Apostichopus japonicus (A. japonicus) processing. However, improper heat treatment can lead to the degradation of protein. In an effort to mitigate this occurrence, we looked into how the protein in the body wall of A. japonicus (AJBWP) was affected by polyphenol oxidase (PPO)-mediated (-)-epigallocatechin gallate (EGCG). The results showed that polyphenol oxidase-mediated EGCG induced protein aggregation. Meanwhile, the antioxidant and thermal stability of the protein were enhanced, and the digestive properties of the protein were inhibited. Protein structure studies have shown that polyphenol oxidase mediated EGCG changes the secondary and tertiary structure of proteins and can maintain the microstructure of proteins after heat treatment. In conclusion, polyphenol oxidase-mediated EGCG was a way to improve the thermal stability of body wall proteins and alleviate the thermal degradation of proteins in A. japonicus.