The dependence of lignin peroxidase (LiP) activities on agitation was confirmed in medium A containing low vitamin and low trace element concentrations. Vigorous shaking (100 strokes.min-1) caused a total loss of LiP activity, and detergents, having a protective effect on the enzyme activity, could not prevent a substantial reduction in enzyme activity. More important, LiP activity also depends on the maintenance media (potato dextrose agar or malt extract agar) and enzyme production media (carbon- or nitrogen-limited). High losses of LiP activity were observed by subsequent subculturing. Even storage of the inoculum on the maintenance media at 4-degrees-C, although better than subculturing, was not advisable. After long storage periods (50-75 weeks) at 4-degrees-C, LiP could not be reactivated in ''poor'' medium A, containing low amounts of vitamins and trace elements. In ''rich'' medium B, containing higher amounts of vitamins and trace elements, even after long storage periods, LiP activity was higher than when the activity was measured in ''poor'' medium A before storage.