Abstract
A new procedures to minimize labor intensiveness and complexity that has long been recognized in cellulase filter paper activity measurement (FPAase) described by the international union of pure and applied chemistry (IUPAC)was developed. It follows the main idea of IUPAC with only exception finding at least two cellulase dilutions have optical densities slightly more and less than a reference optical density of an arbitrary fixed 2 mg absolute glucose amount after a red-ox color reaction and due to cellulase-filter paper hydrolysis. The yielding glucose amount difference as compared to this reference is expressed in terms of absorbance difference percent determined by 3,5-dinitrosalicylic acid (DNS), in case of cellulase is cellubiase rich. If not, an external supplemental portion should be added. The intersection of the line of these two cellulase dilutions with abscissa intersect a vertical at a hypothetical 0% absorbance difference percent corresponding to a critical cellulase dilution exactly release this fixed arbitrary 2 mg glucose amount value. The factor 0.37 of this critical cellulase dilution equals to its filter paper units expressed in FPU per ml.