Abstract:

To develop efficient enzyme preparation used in ramie degumming, the efficient strains used in ramie bio-degumming subjected to lipuid state fermentation, which were screened and accessed. The characteristic parameters of extracellular enzymes including pectinase activity, mannanase activity and protein content, etc. were further determined, and the comprehensive indexes of the ramie degumming system, such as fiber morphology, mass loss rate, residual gum rate, etc. , were analyzed. The results show that pectinase activities of the group N and the group G were 61.79 IU/mL and 13.69 IU/mL, respectively, and their special enzyme activities were 4.47 IU/mg and 0.93 IU/mg, respectively.Gellulase activities of the group  N and the group G were only 0.01IU/mL and 0.02IU/mL, respectively. Their mass loss rate and residual gum rate of the group N and the group G were 20.30% and 18.69%, and 2.52% and 4.21%, respectively, which are close to those of strains in practical industry application. The single fiber fineness of the group Nwas 5.31dtex, and the fracture strength of the bundle fiber was 4.8 cN/dtex,  which belonged to high-quality degummed ramie fiber.

Key words: ramie, degumming, hemi-cellulose, fiber morphology