Abstract
Background: Tuna Cooking Juice (TCJ) is a by-product of canned tuna industry. It usually was either used as protein source of feed meal or directly discharged to wastewater treatment system. However, the soluble proteins in TCJ could be used for producing bioactive peptides by enzymatic hydrolysis. The aims of this study were to produce and purify the anticoagulant and ACE inhibitory peptides from TCJ.
Methods: The bioactive peptides were prepared from tuna cooking juice by enzymatic hydrolysis. In this study, four commercial proteases including alcalase, flavourzyme, pancreatin and pepsin were used for enzymatic hydrolysis of tuna cooking juice. Six biological activities including angiotensin I-converting enzyme inhibitor, anticoagulant, calcium binding, hypocholesterolemic, antioxidant, and antidiabetes were determined. The hydrolysate was performed in an in vitro digestive system. The bioactive peptides were purified by size exclusion chromatography and then high performance liquid chromatography.
Results: The alcalase hydrolysate at the hydrolysate time of 240 and 120 min showed the highest ACE inhibitory of 96.9±0.54% and anticoagulant activities of 92.0±0.75%, respectively. Both ACE inhibitory and anticoagulant peptides from tuna cooking juice hydrolysate were able to survive in an in vitro digestive tract and improve its activities. The molecular weight range of peptides exhibited highest ACE inhibitory and anticoagulant activities was 238-829 and 1355-1880 Da, respectively and these peptides still showed high activities.
Conclusion: Therefore, tuna cooking juice is a potential source of bioactive peptides production used for functional food and neutraceutical ingredients.
Keywords: Tuna cooking juice, enzymatic hydrolysate, commercial proteases, ACE inhibitory peptides, anticoagulant peptides, bioactive peptides.
Graphical Abstract