Cellulase assay - Methylumbelliferyl cellobiose
The substrate solution contained 25mg/ml methylumbelliferyl cellobiose in distilled water. Assays contained 180ml of substrate, 20ml of 0.1M ammonium acetate, 10ml of 0.1M acetic acid. One tube was left as a blank, to another was added 10ml of Aspergillus cellulase (5mg/ml) and to another was added 10ml of Driselase (10mg/ml). One set of samples was incubated 45min at RT and another 45min at 55C. After incubation 10ml of 0.2M Tris was added to each sample (to raise the pH so that umbelliferone fluoresces).
Tubes were placed on a midrange light box and photographed with long 0.4 to 2 sec exposures. The interference filter was wide band (50nm) centered on 450nm.
