Study On Anthelminthic Antibiotic Produced By Actinomycetes CD5872

Parasitic disease has been an important factor restricting the development of animal husbandry,especially,the development of intensive aquaculture has led to the prevalence of parasitic diseases,which is urgently need that people to look for new compound with insecticidal activity from the nature.In the course of our screening for new anthelminthic antibiotics,two antibiotics were from the culture broth of Streptomyces olivoreticuli CD5872 which was isolated from a soil sample collected in Aba prefecture of Sichuan province.Their structures were elucidated.The yield of object compounds were improved by matation breeding and optimizing fermentation medium and conditions.The main research content are:1.Through the studies on culture characteristics,morphological characteristics,physiological and biochemical characteristics,and 16 S rRNA gene sequences analysis of strain CD5872,it is identified as Streptomyces olivoreticuli.2.Study on purification and structure identification of target production.Target compounds were isolated as active secondary metabolite by the technologies such as filtration,ion-exchange column chromatography and silica gel chromatography.Two target compound were separated and named as: CD-1,CD-2.Through infrared spectrum,high resolution mass spectrometry,nuclear magnetic resonance spectroscopy,optical rotation and HPLC,the structure of the two object compounds were elucidated as destomycin A and destomycin C.3.Mutation and screening: the strain CD5872-08 with higher production and stable genetic traits was screened through natural selection.The strain CD5872-08 as original was breeded by method of UV mutation and NTG mutation.And the mutant strain of CD5872-08-02,CD5872-08-01 A and CD5872-08-13 A were screened,with the yield up to 664.6U/mL?625.1U/mL?612.0U/m L(increasing 52.3%,43.6%,40.1%,copparing with original strain),respectively.4.Preliminary study on fermentation process: the mutant strain CD5872-08-02 was used to conduct culture medium and conditions optimization,through single factor experiment and response surface experiment,the constituent and scale of culture medium were confirmed: soluble starch 50.00g/L,glucose 10.00g/L,soybean meal 39.80g/L,yeast extract 10.15g/L,KNO3 0.50g/L,NaCl 2.28g/L,K2HPO4 0.50g/L,MgSO4 0.50g/L,CaCO3 2.00g/L,methionine 5g/L.The titer of destomycin A reached to 1151.4U/mL(increasing 73.2%,compare to that of original fermentation condition).