Abstract:

Four kinds of proteases were used for rape bee pollen protein enzymolysis to prepare ACE inhibitory activity hydrolysates. The ACE inhibitory activity (IC50) of enzymatic hydrolysates was determined by HPLC method. The results indicated that four hydrolysates prepared with different proteases had significantly different ACE inhibitory activities (P ＜ 0.05). The strongest ACE inhibitory activity was observed in alkaline protease derived hydrolysate, with an IC50 of 0.35 mg/mL, followed by neutral protease, papain and acid protease derived hydrolysates. Furthermore, four rape bee pollen protein hydrolysates were applied to a Bio P-2 gel column for fractionization. Fractions with a retention time ranging from 70 to 120 min presented stronger ACE inhibitory activity and statistical analysis showed that their ACE inhibition inhibitory ratios were significantly different (P＜0.05). All of the corresponding fractions separated from alkaline protease derived hydrolysate had more than 90% ACE inhibitory ratio, and their molecular weight distribution varied from 376.4 to 1355 D.

Key words: rape bee pollen protein, protease hydrolysates, ACE inhibitory activity