Isolation, Purification And Structure Identification Of Fermentation Products Of Endophytic Strain HUB-Ⅰ-047 From Termite Tree

Termites have been added into one of the world’s top five pests. They have serious harm to buildings, dams and ecological environment. Therefore, efficient methods of termite control are very necessary and imminent now.Common methods were as followed:physical methods, chemical methods and biological methods.Our thesis carried biological fermentation by using our own killing termites endophytes strain HUB-I-047. Then separated and purified the fermentation products after the fermentation, identified the structures of monomers in the end. At first, extracted the fermentation broth by using ethyl acetate, then recycled the organic phase and concentrated by distillation under reduced pressure to get the crude products. After that, utilized normal phase chromatography, semi-preparative high performance liquid chromatography, gas chromatography, recrystallization techniques and so on. Furthermore, used essential oil extractor which was mentioned in pharmacopoeia to extract the essential oil of HUB-I-047 metabolic products, and applied GC-MS to test the essential oil preliminary. Our experiment used response surface methodology to optimize the strain HUB-I -047 fermentation conditions. Ultimately determined the strain HUB-I-047 optimum fermentation conditions. At last, we got the results were as following, fermentation time 16.7h, incubation temperature 35.54℃, medium pH7.88, rotation speed 180r/min,9.01% of the inoculum size, liquid volume 100mL,0.3% of the carbon sources,0.7% of nitrogen sources.The results showed that the two compounds were initially separated and purified from the fermentation broth of strain HUB-1-047. They were analysed by 1H-NMR, 13C-NMR, GC-MS, HPLC, LC-MS. One compound was 2,6-dimethylphenol and the other one was vanillin.2,6-dimethylphenol is widely used in the production of pesticides, such as polyester which may have a termiticide activity. Vanillin is important spices and synthetic organic materials. By using bio-fermentation and separation and purification methods to get termiticide active substance are green and efficient methods for analysis, and it has a certainly academic research value and broad application prospects in the future.