Screening For The Ergometrine Producing Strain And Analysis Of The Fermentation Condition

mainly used for the treatment of postpartum hemorrhage,subinvolution of uterus and menorrhagia.The biotechnology of ergometriErgometrine is one of the natural ergot alkaloids that were first used in clinic.It isne abroad has reached the level of industrialization,researchers have obtained substantial achievements in screening of strain and optimizing of fermentation conditions.However,there is little progress in domestic research and the country was still unable to carry out industrial production.We choosed about 200 white fungus that were separated from the sclerotias of Paspalum distichum L.,Oplismenus compositus and fescue as the material to screen the strains that producing ergometrine.The screening process used a high-throughput method based on a 48 well-plate-microplate reader.We have obtained 4 fungus having the ergometrine producing ability by a series of analysis methods,including color reaction,TLC,ESI-MS and 1HNMR.Lastly,we choosed one of them that numbered F33 for its better productivity and stability.By morphological identification,homological comparison of 26S rDNA and ITS with the known strains in the Gen bank and analysis of the phyletic evolution tree,F33 was indentified as Clariceps paspali.Different methods were used in the strain improvement,including UV mutagenesis,60Co ?-ray mutagenesis,NTG mutagenesis,acridine orange mutagenesis,rational screening and natural screening.The strain numbered F33-3 was choosed for its better productivity and stability after subculturing among the stains obtained in the strain improvement.The characteristic differences between the strains with high yield and low yield of their colonies and hyphae were studied.The cultivation conditions of F33-3 were studied.We studied the effects of available nitrogen source and slow-release nitrogen source on the seed biomass and ergometrine production,the optimal seed medium was obtained by orthogonal design experiment.The best carbon source,nitrogen source and organic acid of fermentation medium was obtained by singe factor test.Then Plackttt-Burman method selected three significant factors influencing the ergometrine production,they were succinic acid,chick pea meal and P solution.The steepest ascent experiment obtained the best concentration area,Box-Behnken analysis optimized the fermentation medium based on the concentration area.After strain improvement and cultivation optimization,the alkaloid production has been improved to 288.83?g/mL from 73.83?g/mL.The alkaloid production reached 212.67?g/mL on the 10th day when enlarging the experiment in fermentation tank.At the same time,the products in fermentation broth are more purified,which will be another advantage for the further industrial research.