Isolation And Structure Analysis Of Bioactive Products From Myxobacteria Bd105&bd85

Myxobacteria was a class of single-cell gram-negative bacteria with complex behavior patterns and lifecycle, which could produce a wide range of novel metabolites, a considerable number of which were with biological activities such as anti-fungi, anti-bacteria, anti-tumor and so on. These metabolites were important resources for the screening of new natural medicine.In this thesis, the myxobacteria strains BD105 with anti-tumor activity and BD85 with Acetylcholinesterase inhibitory activity preserved by the Key Lab of Microbial Diversity Research and Application of Hebei Province were batch fermented. The active product in broth was extracted with methanol and then a certain amount of fermentation product was obtained through batch fermentation. Through high performance liquid chromatography, a systematic exploration on the isolation, purification and preparation methods of the active product in the broth was conducted, and the isolation, purification and preparation method for the active product in the broth of myxobacteria strains BD105 and BD85 was established. Four compounds were got from each strain and named BD105-1、BD105-2、BD85-1、BD85-2 respectively.Through active surveillance, we found that the four compounds had high biological activity: The inhibition rates of BD105-1 on human cervical cancer cells and human breast cancer cells were 69.19% and 22.59% respectively; and the inhibition rates of BD105-2 on the two cancer cells were respectively 54.76% and 57.12%, indicating good anti-tumor activity; the inhibitory rates of BD85-1 and BD85-2 to Acetylcholinesterase were 56.70% and 55.74% respectively.We have utilized modern spectroscopy testing technology such as ESI、GCT-MS、1H-NMR、13C-NMR、DEPT to do structure solving for the 4 compounds in order to confirm the structures of the compounds. After analyzing, we know that the molecular weight of BD105-1 is 487.68 and the molecular formula is C25H33O3N3S2. The name of the compound is Myxothiazol. Other compounds’structures are being resolved.The study on culture condition of BD105 shows that the optimum culture medium is VY/2. After orthogonal design optimization we know that the optimum media formulations is yeast extract 0.5%, CaCl2·2H2O 0.1%, VB12 0.5μg/mL. The yield of active compounds reach maximum when fermenting 11 days.