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Bamboo fiber is a promising new type of green fiber, with a series of other fibers incomparable advantages, such as antimicrobial resistance, abrasion resistance, moisture absorption, air permeability. China is rich in bamboo resources, the development and utilization of bamboo resources in the textile field, will have a huge economic and social benefits. The use of microbial degumming of the raw material of bamboo fiber has low pollution, low-cost, low-power characteristics. In mutation breeding of lignin-degrading bacteria screening, identification, strains and strains for enzyme production optimization aspects of the study, the results of the system to detect indicators are as follows: colonies on PDA-Azure-B Flat decolorization circle more than 20 soil, humus samples were screened, three strains of Mnp, and Lip enzyme vigor. On this basis the shake flask rescreening final filter out the high strain 1023 dual enzyme production. Mycelium dry weight determination of the growth curve of strain 1023, and 1023 strains mid-logarithmic growth for 70 hours. Kirk medium at 30 ° C and 140rpm shake flask cultures strain 1023 in of eight days Mnp Lip enzyme reached a peak of 403 U / L and 221 U / L. 1023 strain with low energy N ions mutagenic treatment, the implantation energy of 30keV, implantation dose for 100 × 1014ions/cm2, and vacuum 10-3Pa, current strength 10mA, pulse 10s under conditions of N injection, by screening on selective medium and shake flask screening rescreening after subculture the genetic stability experiments visits, mutagenic bacteria N1023j has higher enzyme production stability, its Mnp enzyme activity reached 513 U / L, Lip enzyme activity was 270.9 U / L, than the original strain increased by 27.29% and 22.58%, respectively. By four factors and three levels orthogonal experiment to optimize the fermentation conditions, identified in the incubation temperature of 35 ° C, initial pH 5.5, flask of 100 mL shaking speed 160rpm, high-yielding mutant N1023j fermentation higher enzyme activity. Under Optimal Control high yield the mutant N1023j shake flask fermentation, Mnp Lip enzyme is 631U / L and 340 U / L, respectively, 22.76% and 23.63%, respectively, compared with the original fermentation conditions the next Mnp and Lip enzyme activity. Strains 1023 and N1023j thick bamboo fiber the Microbial Retting test after 30 days of treatment, the 1023 and N1023j two strains of bamboo crude fiber lignin degradation rate of 33.19% and 43.96%, respectively, holocellulose degradation rates were 18.81% and 22.28%, both of lignin degradation selectivity coefficient of 1.76 and 1.97, respectively. Bamboo fiber, pectin, grease wax and lignin are greatly reduced. However, the lignin content is too high, the need to continue processing after the procedure.
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