The Study Of Serratia Marcescens Bacteria Producing Prodigiosin Pigment

The purpose of this study is to obtain the culture of Serratia marcescens yielding bleeding red pigment. Combination of the orthogonal experiment basal medium optimization, combined with the optimization results from the basal medium, the use of a single factor, thereby prodigiosin pigment yielding medium, and this high-yield medium specific detection, identification to optimize yielding medium is the bacteria fermentation prodigiosin pigment exclusive high-yield, low-cost medium, the use of statistical software combined with response surface methodology to validate the optimized medium to prove that the response surface analysis in bacteria fermentation medium optimization, produced prodigiosin pigment Finally, bacteria fermentation production of prodigiosin pigment physicochemical properties, with a view to their subsequent separation and purification lay the research foundation.Serratia marcescens producing prodigiosin pigment of the basal medium with beef extract as the main nitrogen source, while adding peptone, sodium chloride, potassium chloride and other factors, this experiment first basal medium optimized to determine medium turbidity, cell dry weight and acid, alkali absorbance in both environments to evaluate the optimization results, experiments with single factor experiments initially identified Serratia marcescens bacteria producing red pigment, prodigiosin medium of beef extract, peptone Twain.80, of NaCl, NaAc. and KCl, on the basis of the orthogonal test, screening out of the Serratia marcescens coli producing red pigment, prodigiosin best basal medium programs:beef extract 0.3%. peptone 1%, potassium chloride 0.2%. 0.3% sodium chloride.5% Tween 80,0.5% glycerol, NaAcO.2%.Second,experimental studies of peanut, sesame.soy and other natural organic matter as the main nitrogen source alternative to beef extract added to the medium and found that peanut medium is best,soybeans somewhat less; combined with a basal medium optimized results, the Tween 80 added to the medium, prodigiosin pigment production has been greatly improved.peanuts:Soybeans ratio of 3:7 mix and added quality volume ratio of 5% Tween 80 medium to ensure growth and yield of the premisethe next lowest cost. Prodigiosin pigment production spirit in which the fermentation liquid is 17 times the basal medium. Third, to obtain high yield medium, the use of response surface analysis with reference to the two parts of the basal medium and high-yield medium optimization results, beef extract, peanuts, peptone, glycerol. sodium chloride, potassium chloride, Tween 80. acetic acid sodium 8 substances as medium impact factor, design Plackett-Burman experimental screening prodigiosin pigment production factor for glycerol. sodium chloride, beef extract, the final application of Box-Behnken design and response surface analysis to optimize the best fermentation medium, the actual fermentation yield is consistent with the response surface analysis results proved that response surface methodology for the optimization of the medium.Fourth, the experiment of the Serratia marcescens producing prodigiosin pigment medium specific detection to join in the general medium of beef extract as nitrogen source, in this experimental study will beef extract replacement for peanuts as a nitrogen source by adding medium contrast the amount of production of prodigiosin pigment in LB medium, and found a lot of improve marcescens bacteria count in the peanut medium and prodigiosin pigment production, which in fermentation broth red pigment, prodigiosin production of beef extract medium seven times at the same time the strain in LB medium plate counts increased, but almost no production of prodigiosin pigment. Peanuts as the main nitrogen source medium for this yielding the exclusive medium of Serratia marcescens.Finally, experimental pHysicochemical properties of the Serratia marcescens bacteria fermentation production of prodigiosin pigment, organic solvent, ethyl acetate extraction and separation of the red pigment in the fermentation broth, red pigment production of Serratia marcescens after the inspection solubility, UV absorption, as well as temperature, pH. light, metal ions, oxidizing agents and reducing agents on the red pigment, and thin layer chromatograpHy separation characteristics of alcohol solution of the red pigment characteristic absorption peak at 535nm and 470nm. and light, temperature and metal ions in the pigment, but the UV and Fe3+ will destroy the pigment:pigment is more stable in the pH of acidic pH alkaline, will be destroyed: consistent with those reported.The subject of the final study concluded:laboratory self-separation and identification of a Serratia marcescens fermentation production prodigiosin pigment high-yield medium peanut as the main nitrogen source added to the medium topeanuts: so\bean ratio of 3:7 mixed with mass volume than 5% Tween-80 medium under the premise of ensuring the growth and yield the lowest cost.This stems from the peanuts are rich in unsaturated fatty acids:medium at the same time the addition of surfactant Tween 80.changing the membrane permeability of Serratia. produced in the intracellular red pigment released into the extracellular help on improving the yield of prodigiosin pigment.