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C18 hydroxy fatty acid carbon chain length of ω-1, ω-2, ω-3-hydroxy fatty acid (ω-1, ω-2, ω-3-HFA) can be applied to machinery, chemicals, food and other industries, is the green polymer materials research and development in the monomer component of the ideal. In this paper, a short obtained through mutagenesis of Bacillus (Bacillus pumilus) mutant strain M-F641 as the starting strain, in order to further improve the conversion rate of oleic acid and hydroxy fatty acid yield, its growth and metabolism were studied law, and the single factor (incubation temperature, initial pH and liquid volume) on the basis of experiments using response surface analysis, conversion rate of oleic acid as an index to optimize the fermentation conditions, and optimized fermentation conditions were verified. On the basis of carbon metabolism studies to determine the best carbon source is glucose, and microbial fermentation of sugar with intracellular metabolic pathway analysis, xylose as a secondary substrate NADPH coenzyme regeneration achieve the new method. This paper studies the results are as follows: (a) by alkaline and acid methyl ester two different methods were compared, obtained by acid methyl conducted by orthogonal experiment (reaction time, temperature, sulfuric acid - methanol volume ratio) to determine the sulfuric acid - methanol method for fatty acid methyl esters optimal conditions for 2% sulfuric acid - methanol, 70 ℃ water bath for 1h. (2) mutant of Bacillus pumilus strain M-F641 growth and metabolism of studies come to its optimum carbon source required for growth is glucose, and the optimum concentration of glucose 20g / L, and with the intracellular metabolism of glucose analysis of xylose (xylose addition of 10g / L) for the auxiliary substrate for regeneration of the coenzyme NADPH. With and without xylose (0g / L) compared to the control group, NADPH increase the content of 0.0345mmol / L, growth rate of 40.68%; and the control group (oleic acid conversion of 70.04%, ω-hydroxy fatty acid yield 18.90%) compared to the conversion of oleic acid (75.31%), and ω-hydroxy fatty acid yield (22.61%) also have a greatly improved, effective implementation of the coenzyme NADPH regeneration. (3) Bacillus pumilus mutant M-F641 optimum fermentation conditions OK. In univariate (incubation temperature, initial pH and liquid volume) test, based on the response surface optimization method to determine the BP M-F641 optimum fermentation conditions: medium volume 60mL/250mL, temperature 30 ℃, pH value 7.4, in this condition, NADPH maximum content of 0.0268mmol / L, oleic acid conversion was measured at 74.58%.
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