Extracellular laccase production during hyphal interactions between Trichoderma sp. and Shiitake, Lentinula edodes

Lentinula edodes (Berk.) Pegler was cultivated in liquid media containing malt and yeast extract. Extracellular laccase activity, measured in the culture fluids, was 5–18 times higher in cultures incubated for 29 days than in cultures incubated for 24 days. The addition of water-soluble lignin derivatives or Trichoderma sp. in cultures of L. edodes incubated for 11 days increased laccase activity 3- to 20 fold. The higher response was obtained with live mycelium of Trichoderma sp., but cell-free culture fluids of Trichoderma sp. in pure cultures were also effective. Trichoderma sp. induced changes in the laccase isoenzyme pattern as a result of the alteration of laccases secreted by L. edodes and not the induction of new isoforms. Received: 3 November 1997 /  Received revision: 19 January 1998 /  Accepted: 24 January 1998