Characterization of fungi of the genus Mycena isolated from houses thatched with Phragmites communis Trin. in Northern Germany: Enzyme pattern and reed decay

Numerous fruiting bodies of Mycena species were collected from reed-thatched houses in Northern Germany. The fungi were isolated via spore sowing, purified and then characterized in regard to their ligninolytic enzyme pattern. All fungal isolates were able to decolorize the anthraquinone dye Remazol Brilliant Blue R (RBBR) confirming a ligninolytic enzyme activity. In addition, various Mycena species degraded carboxymethyl cellulose and birch wood xylan to varying extents. The strains produced laccase and in some cases manganese peroxidase, which are considered to be key enzymes involved in lignin degradation. The addition of comminuted reed resulted partly in a considerable increase of the laccase activity in liquid cultures. In extensive long-term experiments on solid media with reed as substrate the Mycena species Mycena arcangeliana, Mycena epipterygia variation epipterygia, Mycena galopus variation leucogala and Mycena polygramma caused a significant weight loss of reed between 7.8 and 17.2 % within 70 d. Because of this, we believe that these Mycena species can be classified as reed-decomposing fungi that may affect the quality of reed roofs.