Abstract:

Immunoregulatory factors as bioactive small molecules were prepared from sika deer placenta homogenate using ultrasonic-assisted acetone extraction. Process conditions such as ultrasonic power, homogenate-to-normal saline ratio, utrasonic treatment time and homogenate-to-acetone ratio were optimized using an orthogonal array design to be 400 W, 1:1 (g/mL), 120 min and 1:3 (V/V), respectively. The polypeptide concentration of the extract obtained under these conditions was 30.35 mg/mL. The extract was further ultrafiltrated and a clear yellowish liquid containing immunoregulatory factors was obtained. The liquid contained mainly (3.7 ± 0.04) mg/mL peptides, (3.3 ± 0.07) μg/mL nucleic acid and (0.54 ± 0.002) mg/mL polysaccharides, whereas smaller amounts of polypeptides, nucleic acid and polysaccharides were found in the retentate of the extract after dialysis.

Key words: sika deer placenta, immunoregulatory factors, orthogonal array design, preparation process