Study On Two Microbes Degumming Of Decorticated Ramie

Ramie is a unique fiber crop in China. Ramie fabric has excellent breathability,anti-moth, stiffness, wear and many other advantages. Microbial degumming can reduceacid, alkali, water and coal consumption, and its remarkable economic and social benefitsdrive microbial degumming become the main direction to produce degummed ramie.However, there is no excellent microorganism to biodegrade the complex gum due to thesingleness of degumming enzymes, resulting in degumming incompletely. So, this paperestablished the ramie degumming technology with strain HG-9and strain HG-25cooperatively to obtain stable, high gum removal rate, meanwhile, get high quality ramiedegummed fiber, moreover to solve large-scale use of alkali and bleach problems. Themain study results are as follows.(1) Pectin, hemicellulose and lignin removal rates were85.90%,14.83%and10.34%with the high-yielding pectinase strain of HG-9, and mannanase activity reached99.48U/mL, xylanase activity was only4.88U/mL during degumming process. Pectin,hemicellulose and lignin removal rates were7.33%,34.12%and22.07%with strainHG-25, xylanase activity was44.83U/mL during degumming process. Proved xylanase isthe key enzyme to determine the removal rate of ramie hemicellulose.(2) The degumming technology of decorticated ramie with HG-9and HG-25wasoptimized. The finally optimization degumming conditions were determined such asinoculated volume6%two strains two bacterial inoculum,16:1ratio of water to material,initial pH5.9,37.6°C14h degumming time and not shading. Optimized gum removal ratereached52.91%. Degumming time was shorten2hours and gum removal rate wasimproved9.32%compared with degumming by the strain HG-9.(3) Mixed microbial degumming has a significant effect with HG-9and HG-25.Compered the degumming effect with strain HG-9, the removal rate of lignin reached28.27%, increased17.93%with strain HG-9and HG-25degumming for14hours, at thesame time, Sodium hypochlorite concentration decreased4%. As a result, ramie fiber hasmore white color, less bundle，less strand, and fiber face is smooth, and there is no obvious distortion and damage.