D TEXTILES; PAPER
D21 PAPER-MAKING; PRODUCTION OF CELLULOSE
D21C PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
D21C5/00 Other processes for obtaining cellulose, e.g. cooking cotton linters; ;; Processes characterised by the choice of cellulose-containing starting materials
D21C5/005 Treatment of cellulose-containing material with microorganisms or enzymes