Optimal degumming conditions of strains for microbial degumming of ramie

8-1 strains with the best degumming effect were selected from the collected strains for microbial degumming of ramie. 4-factors( culture temperature,culture time,volume ratio of bacterium fluid and rotate speed) 3-levels orthogonal test was carried out to study the optimal degumming conditions. The experimental results show that culture time is the greatest influence factor,culture temperature and volume ratio of bacterium fluid are followed,and rotate speed is the weakest influence factor. The optimal degumming conditions of 8-1 strains are at 39 ℃ for 4 d,volume ratio of bacterium fluid 1 ∶ 40 and standing for culturing. With these conditions,the ramie degumming rate can reach25. 94%. Furthermore,mechanics performance test and the surface observation were performed the ramie fibers degummed by 8-1 strains. The results shows that compared with those subjected to chemical degumming,single fiber strength of ramie degummed by microbes is improved by 43. 45% and the fiber surface is more smooth and less damaged.