Reid ID
Pulp and Paper Research Institute of Canada, Pointe-Claire, Quebec, Canada H9R 3J9.
Appl Environ Microbiol. 1998 Jun;64(6):2117-25. doi: 10.1128/AEM.64.6.2117-2125.1998.
The fungus Trametes versicolor can delignify and brighten kraft pulps. To better understand the mechanism of this biological bleaching and the by-products formed, I traced the transformation of pulp lignin during treatment with the fungus. Hardwood and softwood kraft pulps containing 14C-labelled residual lignin were prepared by laboratory pulping of lignin-labelled aspen and spruce wood and then incubated with T. versicolor. After initially polymerizing the lignin, the fungus depolymerized it to alkali-extractable forms and then to soluble forms. Most of the labelled carbon accumulated in the water-soluble pool. The extractable and soluble products were oligomeric; single-ring aromatic products were not detected. The mineralization of the lignin carbon to CO2 varied between experiments, up to 22% in the most vigorous cultures. The activities of the known enzymes laccase and manganese peroxidase did not account for all of the lignin degradation that took place in the T. versicolor cultures. This fungus may produce additional enzymes that could be useful in enzyme bleaching systems.
云芝真菌能够去除硫酸盐浆中的木质素并使其增白。为了更好地理解这种生物漂白的机制以及所形成的副产物，我追踪了真菌处理过程中纸浆木质素的转化情况。通过对标记有¹⁴C的木质素的白杨木和云杉木进行实验室制浆，制备了含有¹⁴C标记残余木质素的阔叶木和针叶木硫酸盐浆，然后与云芝一起培养。在最初使木质素聚合之后，真菌将其解聚为碱可提取形式，然后再解聚为可溶形式。大部分标记碳积累在水溶性部分中。可提取和可溶产物为低聚物；未检测到单环芳香族产物。木质素碳矿化为二氧化碳的程度在不同实验中有所不同，在最活跃的培养物中高达22%。已知的漆酶和锰过氧化物酶的活性并不能解释云芝培养物中发生的所有木质素降解情况。这种真菌可能会产生其他酶，这些酶在酶漂白系统中可能会有用。
