1. Elimination and detoxification of softwood extractives by white-rot fungi.
- Author
-
Dorado J, Claassen FW, van Beek TA, Lenon G, Wijnberg JB, and Sierra-Alvarez R
- Subjects
- Biotechnology methods, Cell Wall metabolism, Fatty Acids metabolism, Sterols metabolism, Triglycerides metabolism, Water Pollutants metabolism, Acetone metabolism, Fungi metabolism, Resins, Plant metabolism, Trees microbiology
- Abstract
The ability of several white-rot fungal strains to remove and detoxify acetone extractives (pitch or resin) in Scots pine sapwood was investigated in stationary laboratory batch assays. Fungal pretreatment provided up to 62% total pitch reduction and significant decreases in pitch toxicity. The best strains were Bjerkandera sp. strain Stereum hirsutum and Trametes versicolor that eliminated over 93% of the problematic triglyceride fraction and 58-87% of other lipophilic extractive classes in only 2 weeks. Fungal removal of the wood extractives was accompanied by a 7.4-16.9-fold decrease in their inhibitory effect, as determined in the Microtox bioassay. Wood pretreatment by Bjerkandera sp. and T. versicolor caused limited losses of woody mass (less than 4% in 4 weeks); whereas S. hirsutum led to somewhat higher mass losses (7% in 4 weeks). These results indicate the potential of white rot fungi to control pitch deposition problems in pulping and to reduce the aquatic toxicity caused by naturally-occurring lipophilic extractives in forest industry effluents.
- Published
- 2000
- Full Text
- View/download PDF