Production Of Conjugated Linoleic Acid By Alfalfa Seed Oil

Different kinds of solvents and particle sizes were adopted in the extraction of alfalfa seed oil. The particle size was optimized as 60 and anhydrous aether was chosen as the solvent. orthogonal experiment was implemented to get the most optimized conditions: temperature 40℃, extraction time 80min and the ratio of seed and solvent as 1:7, which led the optimized extraction ratio as 12.93%, and about 29.11% linoleic acid was contained in the extracted oil.The experiment used alfalfa seed oil as the substrate, two kinds of lactobacillus including Lactobacillus plantarum 6026 and Lactobacillus acidophilus 1.1854 to produce conjugated linoleic acid. Pre-incubation, pH values, substrate concentration, lactic acid bacteria concentration, fermentation temperature and fermentatioin time were studied in the conversion of linoleic acid. The research displayed that the additive of alfalfa seed oil in a certain range will enhance the LA conversion ratio. The concentration of lactic acid bacteria, the incubation time, the substrate concentration, the pH, incubation temperature, the pre-incubation time and the substrate amount of pre-incubation were studied in our research and they are optimized at 2.5%(v/v), 21h, 0.05%(v/v), pH 6.4, 37℃, 11h and 10μL which led to the extraction ratio at 51.89%. And the Lactobacillus plantarum are optimized at 10%(v/v), 21h, 0.05%(v/v), pH 7.4, 37℃, 14h and 5μL which led to the extraction ratio at 45.29%.Fermentation dynamics curve was obtained by the study of the Lactobacillus plantarum fermentation. A mathematics model was established based on the cells growth of Lactobacillus plantarum and production CLA accumulation.The catalysis of immobilized Lactobacillus plantarum was studied in the research. An optimized result was found when the sodium alginate gel concentration was 2.5%, CaCl2 concentration was 4% and immobilized time was 5h, with which level the immobilized cells showed the best performance. With the purpose of optimizing the whole process of the LA conversion with immobilized cells, the cell amount, reaction time, pH value, temperature and substrate concentration were studied and optimized as 5mL, 12h, pH7.5, 40℃and 0.05%, which brought LA conversion 23.23%. After reusing the immobilized cells, the LA conversion incorporated was about 50%.