产共轭亚油酸乳酸菌的选育及培养基的确定

共轭亚油酸(conjugatedlinoleicacid简称CLA)是一种具有多种生理活性的天然脂肪酸。用气相色谱法对十八株乳酸菌产共轭亚油酸的能力进行比较,发现十四株乳酸菌具有明显的产共轭亚油酸的能力,其中德氏乳杆菌保加利亚亚种(L.delbrueckiisubsp.bulgaricus)a2的产量最高,为4.06μg/mL,并且在MRS培养基的基础上确定了乳酸菌产共轭亚油酸的最佳碳源为果糖,氮源为硫酸铵。

Conjugated linoleic acid (CLA) is natural fatty acid that has a great variety of physiological activity. The investigation determined CLA-producing capacity of eighteen lactic acid bacteria. The level of CLA formation was determined by gas chromatography. There were fourteen lactic cultures that could produce conjugated linoleic acid. L.delbrueckii sub sp. and L. bulgaricus a2 have the highest level of conjugated linoleic acid, the level was 4.06μg/mL. The optimal medium with which lactic acid bacteria could produce conjugated linoleic acid was MRS medium:carbon source was fructose; nitrogen source was ammonia sulfate.