B rown Ro t is caused by Basidiomvcetes, which metabolize the carbohydrates cellulose and hemicelluloses of the woody cell wall by non-enzymatic and enzymatic action and leave the lignin almost unaltered , whereby the brown color develops. Brown-rot fungi do not produce lignin-degrading enzymes. There are how-ever reports of lignin peroxidase and manganese peroxidase in some brown-rot fungi, and lignin loss or metabolization by brown-rot fungi have been reported. Particularly in later stages of decay, the highly lignified middle lamella/primary walls were observed to undergo attack. Also, the penetration of the wood cell wall by bore holes removes lignin in the process, all suggesting that low molec-ular weight lignin degrading agents and potentially even lignin degrading enzymes max occur in some brown-rot fungi, at least with localized activity (Goodell 2003). Laccase activity was also found in Coniophora puteana (Lee et. al. 2004), and in Glocophyll...
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