The Research On The Secondary Metabolites From Xenorhabdus Nematophila SN313 And Their Biological Activity

The organism maintains its surroundings by using its secondary metabolites.The secondary metabolites of many organisms have the function of resisting other organisms,such as anti-virus,anti-bacterial,insecticidal,herbicidal biological activities.With the development of science and technology,People first made use of mixtures and later extracted pure compounds from them.People use purified compounds in medicine or pesticides.A special symbiotic relationship exists between bacteria,nematodes and insects.The abundant secondary metabolites of entomogenous nematode symbionts have attracted people’s attention,Some literatures have shown that these compounds have insecticidal,bactericidal and anticancer effects.In this experiment,the pure compound was separated and passed by microbial fermentation,liquid adsorption,column chromatography and HPLC preparation.Their structures were determined by MS,NMR spectroscopy.Reference data to determine chemical structure.The 24-microwell plates was used to detect the activity of the M.incognita.The activity of the isolated compounds was determined by using a glass tube to target Trialeurodes vaporariorum.In this paper,compounds with biological activity were found by the separation and purification of secondary metabolites of nematophilus.The biological activity of the isolated compounds was used as a basis for the development of new pesticide lead compounds.The main results are as follows:The primary strain of Xenorhabdus nematophila was screened,and the secondary metabolites were obtained by collecting the fermentation broth through liquid fermentation,from which 4 compounds were isolated.The structure identification results of the four compounds were as follows,1h-indole-3-ethanamine(2),formamide(n-[2-(1H-indol-3-yl)ethyl]-(3)and n-acetyltryptamine(1)with new chemical structure,N-[2-(1H-indol-3-yl)ethyl]-)(4).The bioactivity of nematodes with M.incognita as the target was determined as follows.The LC50 of Formamide,N-[2-(1H-indol-3-yl)ethyl]-is 14.675μg / m L.The LC50 of Acetamide,N-[2-(1H-indol-3-yl)ethyl]-is 18.068 μg/m L.The LC50 of Newly discovered amphetamine-like compounds is 26.808 μg/m L.The three main compounds showed good biological activity against M.incognita.The LC50 of 1H-Indole-3-ethanamine is 145.602 μg/m L.The biological activity of this compound against the target M.incognita was weak.