Abstract: In order to solve the problem of indigo back staining in cellulase bio-washing, the effect of anionic surfactant (SDS), zwitterionic surfactant (PC), nonionic surfactants (T60 and AEO-9 ) on cellulase adsorption and hydrolysis were first detailed analyzed. And then, the effect of complex system of different surfactants on denim bio-washing was further studied. The results showed that the selected surfactants had a slight effect on indigo adsorption with cellulase. However, anionic surfactant and nonionic surfactant could decrease the adsorption amount of cellulase on micro-crystalline cellulose. For the cellulase hydrolysis, anionic surfactant greatly reduced the cellulase activity, while zwitterionic surfactant and nonionic surfactants had little effect on cellulose, and even had certain activation. Finally, the CIE L and CIE |b| values showed that the synergism of anionic surfactant and nonionic surfactant didn’t reach a good bio-washing result while the synergism of non-ionic surfactants had a better performance.

Key words: surfactant, cellulase, absorption property, hydrolysis property, back staining