The Screening Of A New Microbe S.Marcescens And The Stuty Of Anticancer Function Of The Red Pigment Produced By The Strain

Prodigiosin is a type of red secondary metabolites produced by Serratia marcescens, which is a molecule contains three conjugated pyrrole rings. With prodigiosin-depth study, it was found that prodigiosin has anticancer, antibacterial, antimalarial, and algal immunosuppressive function. Anticancer advantage prodigiosin mainly reflected in the targeted cancer cells as a novel anticancer drug precursors, research coli and prodigiosin of Serratia attracted wide attention of scholars.In this paper, the completion of the screening and identification of the mandarin fish gut strain Serratia marcescens strains and named S.marcescens HFUT 1301; pigment separation, purification and identification; Optimization of medium components and fermentation conditions to increase pigment production; MTT assay prodigiosin by lung cancer cell A-549, MCF-7 breast cancer cell growth inhibition, inhibition study prodigiosin on two common cancer cells. The main contents and results are as follows:(1) By a single colony observation, physiological and biochemical identification of bacteria and 16S rDNA sequence analysis, and the NCBI database comparison and identification of a test to determine the resulting strain is a new type of Serratia marcescens, and named S.marcescens HFUT 1301.(2) The structure of the pigment analysis:By UV-Vis full wavelength scanning, LC-MS, FT-IR and NMR spectra for structural analysis and identification of the pigment,the pigment is determined prodigiosin pigment formula C20H25N3O, correspondence a molecular weight was 323,then caculate its structural formula.(3) In order to improve the production of prodigiosin produced by S.marcescens HFUT 1301 on the medium composition. Fermentation conditions were optimized, the results show that:a soybean oil, peptone, sodium chloride and potassium phosphate dibasic content was 4%(v/w),1.5%(w/w),0.15%(w/w) and 0.15%(w/w), respectively; fermentation conditions was:temperature 30℃, inoculum 1%(v/v), liquid volume 70 mL/250mL flask, shaking speed of 200 r/min, after 36 h of fermentation, prodigiosin’s production up to 2.98 g/L.Serratia marcescens corresponding extracellular lipase activity was 20 U/mL.(4) Using the MTT assay with different concentrations of prodigiosin inhibition of cancer A-549 and MCF-7 growth.To the maximum plasma concentration range, prodigiosin on human lung cancer cell A-549, human breast cancer cell MCF-7 maximal inhibition rate was 78%,83%, respectively.