Enzyme affinity towards purified lignin. LM (1) and CLSM images (2, 3) of purified lignin incubated with a fluorescently labelled endoglucanase (A) or exoglucanase (B). Each row shows one identical motive taken with the same objective (4x). CLSM images were captured using the same laser intensity of 20% but with different gains, i.e. 500 V (2) and 700 V (3), respectively. Notice that no emission is detected at ‘standard’ 500 V, only after a significant increase in gain to 700 V.