Optimization on condition of glycyrrhetinic acid liposome by RSM and the research of its immunological activity.

The aim of this study is to prepare glycyrrhetinic acid liposome (GAL) and optimize the preparation condition and to investigate further whether liposome could promote the immunological activity of glycyrrhetinic acid (GA). GAL was prepared using a film-dispersion method and the preparation conditions of GAL were optimized with response surface methodology (RSM). Moreover, GAL prepared under the optimal preparation conditions was added into chicken's T and B lymphocytes in vitro. The optimal preparation conditions for GAL by response surface methodology was as follows: ratio 9:1, soybean phospholipid cholesterol (w/w) 2.5:1 and water bath temperature 31 °C. Under these conditions, the experimental encapsulation efficiency of GAL was 83.46 ± 0.55%, which was close with the predicted value. Therefore, the optimized preparation condition is very reliable. The results showed that GAL could significantly promote T and B lymphocytes proliferation singly or synergistically with PHA and LPS and the concentration of immunoglobulins G (IgG) and immunoglobulins M (IgM). These results indicated that liposome could significantly improve the immunological activity of GA and drug action of GA. GAL demonstrates the significant immunological activity, which provides the theoretical basis for the further experiment in vivo.