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Taxol is a diterpenoid derivatives, is currently recognized as a broad-spectrum activity of anti-cancer drugs. 1992 was approved by the U.S. Food and Drug Administration (FDA) as a new drug against advanced cancer listed. As the main source of paclitaxel rely increasingly poor yew bark, resulting in high prices in the international market, so look for other production methods and abroad has become one of the hot. At home and abroad in recent years, many researchers have reported isolated taxol-producing fungi. The paper produced by microbial fermentation yield of taxol as the goal, to get a higher yield mutant K178 on the beautiful isolates of Fusarium (Fusarium mairei) Y1117 protoplast mutagenesis and screening, and its fermentation The conditions were optimized to further increase production. Its main research methods and results are as follows: by orthogonal experimental design method, a detailed study of the medium composition, composed of enzymes, cell age, osmotic buffer, pH, reaction temperature, time and Regeneration culture way a variety of factors beautiful Fusarium Protoplast preparation and regeneration. Experimental results show that the beautiful Fusarium through the first stationary 2D 180r/min Seismic shake 2d formulated in 0.6mol / L KCl pH 5 enzyme complex (3% Lywallzyme, 2.5% snailase 1% lysozyme and 0.5% cellulase), 32 ° C temperature hydrolysis 4h, protoplast preparation yield of 3.2 x 107 / mL; purified protoplasts in 25 ° C, 0.6 mol / L sucrose preparation The YCM regeneration medium of monolayer cultures, the regeneration rate of 8.9%. 2. Protoplast mutagenesis and screening methods. Dose conditions, respectively, by UV irradiation and DES role in research on the spores and protoplasts survival, change. To determine which mutagenesis: UV irradiation (15W, 30cm distance) 30s, DES final concentration of 0.2% treatment for 30 min. In the routine screening based on the research to find the right drug sieve. Drug screening By comparing several antifungals and effect, select as the to 3μg/ml the nystatin results showed that its role is the high mutation rate of 13%. At the same time, select the highest yield an K178 for further fermentation studies. (3) the use of statistical methods to the basic medium composition series of optimization studies, results showed that the optimal medium composition: glucose 80 g / l, NH the 4 NO 3 7.84g / l, sodium acetate 2.02 g / l, the the MgSO 4 0.68 g of / l, KH are 2 PO 4 0.5 g / l, ZnSO 4 1 × 10 -3 g / l, Cu (NO 3 ) 2 1 × 10 -3 g / l, FeCl 3 2 × 10 -3 g / l, VB1 50 × 10 -3 g / l, L-tyrosine 5 × 10 -3 g / l. Under these conditions, fermentation the paclitaxel yield of up to 225.2μg / l. Several precursor role in this study on the basis of the results showed that phenylalanine, an appropriate amount of sodium benzoate and catechol added can improve Taxol Yield. The same time, based on the logistic equation was established to describe the kinetics model of batch fermentation process mycelial growth.
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