Study On Fermentation Production Technology Of Polyoxin Against Black Spot Disease Of Panax Notoginseng

Panax notoginseng,is a perennial erect herb of the genus Panax in the umbelliferae family,enjoying the reputation of "King of Ginseng","Nanguo Shencao”and "Jinbuhuan”etc.It's medicinal use has a long history.Black Spot Disease is a common disease in the cultivation and production of Panax notoginseng,with an annual incidence of 10%to 20%,and in severe cases as high as 80%or more,has become one of the destructive diseases of Panax notoginseng.The Black Spot Disease of Panax notoginseng is caused by the contamination of Alternaria panax Whetzel.The pathogen belonging to the Deuteromycotina,Hyphomycetes,Moniliales,Dematiaceae,Alternaria.Polyoxin,a nucleosides of peptide pyrimidines broad-spectrum agricultural antibiotic produced by modern bioengineering technology,has been applied to the biological control of Panax notoginseng Black Spot Disease in recent years with good effect.This thesis research industrial fermentation production technology of Polyoxin,first of all,based on the Shaanxi Microbe Biotechology CO.,LTD production strains of Polyoxin,selection of Panax notoginseng Black Spot Disease pathogen Alternaria panax Whetzel efficiency of the strains of inhibition,further study on fermentation process and product separation extraction process,improve production efficiency,reduce production costs.The main results were as follows:1.The agar diffusion method was used for the selection and selection of Polyoxin-resistant strains that effectively inhibited the pathogen of Panax notoginseng and established a set of rapid and efficient selection methods.Taking Panax notoginseng pathogenic bacteria as the test bacteria,the self-made glass-plated double-layered culture medium antibacterial circle method,shake flask screening method and biological tube dish method were used to determine the biological titer technology Streptomyces aureochromogenes—18#.2.The single-factor and orthogonal test were used to optimize the shaking flask fermentation conditions of the Polyoxin-producing bacteria Streptomyces aureochromogenes—18#for the control of Panax notoginseng Black Spot Disease,and the best fermentation medium was obtained recipe and fermentation conditions.Fermentation medium formula:corn flour 7%,cold-pressed soybean cake flour 3%,yeast flour 0.8%,fish meal 0.75%,KH2PO4 0.02%,NaCl 0.2%,CaCO3 0.5%,pH 6.5.Fermentation conditions:300 mL wide mouth triangular bottle with a volume of 50 mL,fermentation temperature of 28?,rotation speed of 200 r/min,and fermentation culture period of 120 h.Under the conditions of this process,the average fermentation titer of Streptomyces aureochromogenes—18#Polyoxin was 4374.6 ?g/mL,and the relative growth rate was 38.7%.3.Using 5 L—15 L—50 L triple parallel nine-link Distributed Control System control system fermentation tank,the selected Streptomyces aureochromogenes-18#was optimized fermentation medium and fermentation conditions,three batch fermentation experiments were carried out.Detecting by a fermentation process biological potencytotal,cell density of biochemical indexes,sugar regulation,reducing sugar,ammonia,phosphorus content,dissolved oxygen,pH other parameters of the fermentation process to optimize production strains.4.The use of a roll-type nanofiltration membrane separation system with a relative molecular mass of 300?1000 Da for separation and extraction of Polyoxin,after separation and extraction,the Polyoxin content of the purified solution was greater than 4%with a pH of 3.50-5.00.A high-yielding strain of Streptomyces aureochromogenes—18#was selected to inhibit the pathogenic bacteria of Panax notoginseng Black Spot Disease,and the shaking flask and small-test fermentation processes were optimized.The separation and extraction process of Panax notoginseng Black Spot Disease by nanofiltration membrane was established.This study laid a foundation for the industrialization of Polyoxin against Black Spot Disease of Panax notoginseng.