ADDITIVE EFFECTS OF CuSO4 AND AROMATIC COMPOUNDS ON LACCASE PRODUCTION BY Pleurotus sajor-caju PS-2001 USING SUCROSE AS A CARBON SOURCE

Laccase enzymes are now commercially available, and a laccase/mediator combination is currently marketed for indigo dye bleaching in textile manufacturing; replacing traditional chemical-based processes with enzymatic technology reduces the need for effluent treatment. However, an inexpensive source of these enzymes will be needed to enable wider application of this technology. In the present work, the main objective was to increase laccase production by the mushroom Pleurotus sajor-caju strain PS-2001 grown on sucrose derived from sugar cane, one of most economical carbon sources known, by the addition of compounds that are known to affect laccase production. High laccase activities (45–62 U mL) were obtained with additions of syringaldazine, benzoic acid, gallic acid, and vanillin. When CuSO4 was used in conjunction with these aromatic compounds, the levels of laccase activity were further improved, reaching 58–80 U mL. These laccase activities indicate the potential of this strain as an enzyme producer, which has also been detected in media containing glucose, but with activity lower than that observed with sucrose.