MODIFICATION OF PAPER PROPERTIES BY THE PRETREATMENT OF PULP WITH SACCHAROMONOSPORA-VIRIDIS XYLANASE

The thermophilic actinomycete Saccharomonospora viridis was found to produce extracellular xylanase activity in the absence of detectable activity against cellulose. This property was exploited by the application of crude enzyme preparations to birchwood pulp and resulted in the selective removal of approximately 20% of the total xylan present. Paper handsheets prepared from pulp treated in this way demonstrated modifications in a number of physical properties, of which a decrease in burst and long-span tensile strength were the most significant. The results, together with those on the treatment of cotton pulp with S. viridis xylanase and a commercial cellulase, suggest that specific removal of xylan reduces the extent of interfiber bonding but does not significantly weaken the fibers themselves. The role of xylan in pulp and paper properties and the potential use of S. viridis xylanase in both research and commercial applications are discussed. © 1990.