Structural Characterisation and Enzymatic Degradation of Exopolysaccharides involved in Paper Mill Slime deposition

Bacteria that adhere to the surface of a paper machine form a biofilm that entraps the fibres and additives used as raw material to form a slime deposit. The formation of these slime deposits can result in serious problems with respect to the papermaking process itself and the end product. Traditionally more or less toxic biocides are used to prevent this problem. However, due to more strict environmental legislation there is growing interest in alternative methods for slime control. One of these methods could be the use of enzymes that degrade the exopolysaccharides (EPSs) that form the major structural element of a biofilm. To obtain these enzymes it is important to know which EPSs to target for enzymatic degradation. Therefore the EPSs produced by several species isolated from different paper mills within Spain, Finland or France were subjected to a (detailed) chemical structure elucidation. From these studies several EPSs were selected as target substrates for enzymatic degradation. The enzyme able to degrade one of these substrates was subjected to purification and characterisation studies