The effect of oxidation on the structure of G-actin and its binding ability with aroma compounds in carp grass skeletal muscle

To investigate the influence of oxidative modifications of G-actin on its binding ability with aroma compounds, the influence of H2O2 treatments on G-actin structure and the absorption for alcohols and aldehydes was investigated. Raman spectroscopy and scanning electron microscopy were used to evaluate structural changes of G-actin; GC–MS was used to analyze the binding with alcohols and aldehydes. Results showed that 0–5 mM H2O2 enhanced the absorption of G-actin toward alcohols involved in the formation of hydrogen bonds by increasing α-helix and carbonyl values. 0–1 mM H2O2 caused the release of aldehydes with decreased sulfhydryl sites. 1–20 mM H2O2 increased the retention of aldehydes, due to the increased hydrophobic sites by G-actin rebuilding and aggregating. The aggregated G-actin favoured the hydrophobic interactions with aroma compounds, forming the protein-aroma compound complex, thus enhancing the resultant binding ability, as evidenced by scanning electron microscopy and GC/MS analysis.