| Neopolyoxin is a kind of new antifungal and insecticidal antibiotics. To optimize the production technology for Neopolyoxin overproducing strain,the study we have done were as follows:1.We drew a standard curve to show the relationship between zones of inhibition and concentration of Neopolyoxin. The linear range of standard curve was 25-100 [g /ml, r> 0. 99.2. On shaking flask level, we screened the optimum carbon and nitrogen sources by single-factor experiment in fermentation media. Then, we screened the optimum level of every component of the fermentation media by orthogonal experiment. We also investigated the pH before sterilized, temperature, volume and agitation. The optimum condition to higher chemical potency was obtained: fermentation media: flour 3%, soybean powder 4%, yeast powder 0.1%, MgSO4 0.1%, NaCl 0.1%, CaCO3 0.2%, mannite 0.4%; pH7.0 before sterilized, temperature 28℃, volume 40ml/500ml, agitation 210r/min. The chemical titer can reach 11600μg/ml3. The fermentation curve of nikkomycin high-producing strain t-53 was studied in this dissertation.4. The absorption capacity and selectivity of various kinds of cation-exchange resins to nikkomycin fermentation broth were compared. A highly selective absorption capacity to nikkomycin, 001 × 4,was chosen. The optimum conditions are as follows: fermentation broth adjusted to pH3.5,flow rate 2BV/h,and eluted with 0.4mol/L ammonia water,flow rate 0.5 BV/h.5.To promote the value of Neopolyoxin, the inhibition activity of Neopolyoxin to the phytopathogen was tested in this research. Neopolyoxin had wide spectrum and had strong inhitory activity against plant pathogenic fungi,especially for fungi of Alternaria. But showed little effect on tested phytopathogen bacterium.
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