Department of Animal Science and Biotechnology, Kyungpook National University, Daegu 702-701, Republic of Korea.
N Biotechnol. 2010 Sep 30;27(4):352-7. doi: 10.1016/j.nbt.2009.11.005. Epub 2009 Nov 29.
The hydroxylation of unsaturated fatty acids by bacterial strains is one type of value-adding bioconversion processes. This process generates new hydroxy fatty acids (HFA) carrying special properties such as higher viscosity and reactivity compared with normal fatty acids. Among microbial strains tested for HFA production, Pseudomonas aeruginosa PR3 is well known to utilize various unsaturated fatty acids to produce mono-, di- and tri-hydroxy fatty acids. Previously we reported that strain PR3 could produce a novel value-added hydroxy fatty acid 7,10-dihydroxy-8(E)-hexadecenoic acid (DHD) from palmitoleic acid (Bae et al. (2007) Appl. Microbiol. Biotechnol. 75, 435-440). In this study, we focused on the development of the optimal nutritional and environmental conditions for DHD production from palmitoleic acid by PR3. Optimal carbon and nitrogen sources for DHD production were fructose and yeast extract, respectively. Optimal initial medium pH and incubation temperature were pH 8.0 and 30 degrees C and magnesium ion was essentially required for DHD production. Substrate concentration and time of substrate addition were also optimized. Under optimized conditions, maximal DHD production was 1600mg/l representing 26.7% conversion yield.
不饱和脂肪酸的羟化作用是细菌菌株增值转化的一种方式。与正常脂肪酸相比，该过程生成了具有特殊性质的新的羟基脂肪酸（HFA），例如更高的粘度和反应性。在测试用于生产 HFA 的微生物菌株中，铜绿假单胞菌 PR3 是众所周知的能够利用各种不饱和脂肪酸生产单、二和三羟基脂肪酸。之前我们报道过，菌株 PR3 可以从棕榈油酸（Bae 等人，2007 年，应用微生物学与生物技术，75,435-440）生产一种新型的增值羟基脂肪酸 7,10-二羟基-8(E)-十六烯酸（DHD）。在这项研究中，我们专注于开发 PR3 从棕榈油酸生产 DHD 的最佳营养和环境条件。DHD 生产的最佳碳源和氮源分别是果糖和酵母提取物。最佳初始培养基 pH 值和培养温度分别为 pH8.0 和 30°C，并且 DHD 生产需要镁离子。还优化了底物浓度和底物添加时间。在优化条件下，DHD 的最大产量为 1600mg/L，转化率为 26.7%。
