Glycoprotein fraction of CA-SIIF demonstrated higher inhibitory effect on human monocytes IL-12 production. CA-SIIF was passed through a ConA lectin affinity column. Both resulting fractions and CA-SIIF crude were tested for the effect on IL-12 production of 1 × 106/ml human monocytes. (A) glycoprotein fraction (CA-SIIF-GP) successfully achieved higher inhibitory effect than the non-glycoprotein (CA-SIIF-NGP) fraction (P < 0.01). (B) Inhibition efficiency of CA-SIIF-GP fraction is significantly higher compared to CA-SIIF crude and CA-SIIF-NGP (P < 0.01). Fold decrease was calculated by decrease of the IL-12 level by percentage; inhibition efficiency was determined by evaluating the fold decrease of IL-12 level/protein dose ratio.