Laccase (EC 1.10.3.2) (Denilite IIS) is a multi-copper oxidase (MCOs), which widely exists in microorganisms, plants and fungi, and can catalyze the oxidation of one electron of various phenolic compounds. Laccase can promote the oxidative coupling of single lignin, which plays an important role in the formation and biodegradation of lignin, and also has the potential to cross-link food polymers^[1].