Abstract:

The extraction condition of protein from Zizyphi spinosi Semen by alkaline extraction and acid precipitation
was optimized by response surface methodology. The extraction efficiency of protein was investigated with respect to
four variables including solvent/solid ratio, pH, temperature and time. A mathematical model was fitted by means of Box-
Behnken design. The optimum conditions for extracting protein from Zizyphi spinosi Semen were determined as 24:1 (mL/g),
11, 57 ℃ and 46 min for solvent/solid ratio, pH, temperature and time, respectively. Under these conditions, the maximum
theoretical extraction yield of protein was 73.15%, which closely agreed with the actual value of 73.11%. Thus , the model
developed in this study has good prediction capability.

Key words: Zizyphi spinosi Semen, protein, alkaline extraction and acid precipitation method, response surface methodology