Study On Selection And Application Of Microorganism For Hemp Degumming

Hemp is an essencial crop with superior fibers,which fiber products are becoming increasingly popular for parallel distributed computation because of its moisture-absorbing,breathable,antibacteristics and radiation shielding.However,duo to hisrtorical reasons and the inherent properties of itself,hemp textile processing technology was not mature enough.And compared to traditional chemical degumming process,the quality of the hemp fiber,energy costs,environmental pollution,bio-degumming technology has great advantages and good prospects.The main constituents of hemp fibers are pectin,hemicellulose,lignin and the results show that the strain capable of producing high pectinase and hemicellulase which can reduce the residual gum content and improve the cellulose content.Two function strains of degumming hemp,13#and 16#were isolated from the microorganism powder of our laboratory perserverd.Two strains were both indentified as Bacillus subtilis accroding to the morphological,physiological,biochemical characteristics and the seguencing of 16S rDNA.The strain has the high production capacity of pectinase and hemicellulase and no cellulase.Degummed hemp residual gum is 21%and 20.5%by 10 hour,which proverd to be both effective degumming strains.Singal factors test method was used to optimize the most suitable degumming conditions for temperature,liquor ratio,nitrogen source,shaking rate and the amount of inoculation.The optimal operation condition of the strain for hemp degumming were determined as:37℃,180 r/min,liquor ratio 1:20,contentration 5%,NH4NO3 0.2%.The most important condition is liquor ratio by orthogonal experiments.Under the optimum conditions,the raw hemp was degummed for 4 days by singal or together.Correspondingly,the residual gum rate was only about 13%and the cellulose content increased to 82%.Without obvious damage by SEM,the fiber was completely divergent and bright color white and the most of the gum was removered.In order to degradated the lignin of the hemp.Hemp was degummed by Bacillus subtilis for 4 days and Phanerochaete chrysosporium continued degumming for 7 days.The lignin content of the degummed hemp was lowered 1.2%.Without obvious damage by SEM,the fiber color was more divergent and bright.