HPLC preparation of fish waste hydrolysate fractions. Effect on guinea pig ileum and ACE activity

The effect of RP-HPLC-purified fractions of fish waste hydrolysates issued from three fish industries was tested on guinea pig ileum in order to examine the presence of opioid molecules. The evaluation of anti-hypertensive activities of whole hydrolysates and fractions were also tested, monitoring the ability of the fraction to inhibit the activity of angiotensin I-converting enzyme involved in hypertension regulation. Sardine autolysate and cod head hydrolysate powder (50 microg) were able to inhibit near 30% of ACE activity, whereas 50 microg of shrimp hydrolysate allows the inhibition of 57% of ACE activity. HPLC fractionation of cod head hydrolysate and sardine autolysate was necessary to evidence biological activity, whereas HPLC separation of shrimp hydrolysate exhibited low biological activity fractions. Further studies are necessary to characterise bioactive molecules from cod head alcalase hydrolysate and from sardine autolysate.