Open access publications in the SLU publication database

Abstract

The ability of the soft rot fungus Humicola alopallonella Meyers & Moore to form cavities in various cellulose fibres has been studied. The following fibre materials were tested: wood of aspen, beech, birch, pine and spruce, three sulphate pulps with different lignin content, spruce holocellulose, Avicel, Sigmacell T38, flax, jute, ramie, sisal, cotton, kapok, seed hairs of Salix pentandra L, and two viscose rayon fibres. In addition the degradation of cellophane was studied. Typical soft rot cavities were formed in all the natural fibres except for spruce holo cellulose tracheids. The cavity formation in fibres like Avicel, Sigmacell T38 and cotton which contain no or possibly minute amounts of lignin and hemicelluloses, shows that these substances are not needed for cavity formation per se. The shape of the cavities is rather similar in all the natural fibres, indicating that the explanation of the form of the cavities must be sought in the crystalline structure of the cellulose. Various aspects of the process of cavity formation are discussed in the light of the new findings.