[Separation of gamma linolenic acid from evening primrose oil with urea inclusion--orthogonal experiment of optimizing technological parameters and observation of urea inclusion compound I].

Objective: The influence on the urea inclusion compound under different conditions (allocated proportion, time of inclusion, temperature of inclusion) were studied through the orthogonal test, and theoretical reference of urea inclusion process for further optimization wound be offered.
Method: The orthogonal experiment was adopted, and microscope was used to observe the shape, aperture size of the urea inclusion compound under different technological parameters, the GC was employed to inspect the purity of GLA.
Result: The results indicated that the ratio of fatty acids and urea, inclusion of temperature, time of inclusion had great effect on urea inclusion compound. The three factors and its interactions significantly affected the purity of GLA. The results also showed that the best process was that the ratio of fatty acids and urea was 1 : 3, temperature of inclusion was--15 degrees C, time of inclusion was 24 h.
Conclusion: Under the best condition, the purity of GLA reach up to 95.575 9%; and it is feasible to observe the shape and the amount of the urea inclusion compound to reflect and guide the urea inclusion technology.