Viswanath, B., Rajesh, B., Janardhan, A., Kumar, A. P., & Narasimha, G. (2014). Fungal laccases and their applications in bioremediation. Enzyme research, 2014.
Viswanath, B., Rajesh, B., Janardhan, A., Kumar, A. P., & Narasimha, G. (2014). Fungal laccases and their applications in bioremediation. Enzyme research, 2014.
I'm not sure which assays the other responses use but, I've used 1,8 diaminonaphthalene in media to detect PPO/laccase activity, see: Article Staining Electrophoretic Gels for Laccase and Peroxidase Act...
Alternatively, dye (especially remazol brilliant blue R) decolorization can also be used to detect laccase activity in cultures: Article Industrial Dye Decolorization by Laccases from Ligninolytic Fungi
Article Redox-mediated decolorization of synthetic dyes by fungal laccases
Article Decolourisation Capabilities of Ligninolytic Enzymes Produce...