| dc.description.abstract | The growing world population comes with a serious concern on how to sustainably meet the people's nutritional demand now and for the generations to come. The double burden of disease which is a surge in communicable and non-communicable disease, which is further exacerbated by globalization in the 21st century has made the sustainable future not forthcoming. Significant effort to address this problem as part of the sustainable development goals is required to intensify. In this regard, the ocean has been identified to be a good source of protein containing food which can potentially solve the world food requirement through sustainable aquaculture and development of novel technology. New marine fish resources of the mesopelagic zone contain vast amounts of biomass that can be exploited to support the regular aquaculture. Protein hydrolysate of these marine mesopelagic fish has also been argued to be exerted antioxidative and antihypertensive inhibitory attribute. This, therefore, longing for new research to establish and refine the position of marine mesopelagic fish in the sustainable future.
Biomass containing two and one mesopelagic fish were processed and investigated in batches. Raw materials sample were subjected to enzymatic hydrolysis, and the recovered samples were filtered and freeze dried to a finely refined protein hydrolysate powder. The aim of this thesis was to study the nutritional composition of these mesopelagic fish protein hydrolysate, by conducting the proximate composition, evaluate the antioxidative activity, and antihypertensive activity. Also conducted molecular peptide sequencing to know the molecular weight of peptides fraction after membrane filtration. Furthermore, to determine the degree of hydrolyzation, and to examine the yield of the protein hydrolysate and discuss possible optimization.
Protein hydrolysate from both batches displayed high protein, and other constituent were within expected range described for marine fish. The protein hydrolysate showed high content of lysine, leucine, glycine/arginine and, and glutamate. The antioxidative capacity was shown high when measured by FRAP and ABTS, but low when measured by ORAC. The result of the sample containing only pearlside were extremely low compared to the sample containing both krill and pearlside. However, there is a need for pre clinical and human clinical trial to verify these results and establish safe dosages. The molecular weight distribution has shown high content of smaller peptides < 2kDa in all protein hydrolysate. With the abundance of lysine, leucine, and glycine in the free amino state. di-, tri-, tetra-peptides containing these essential amino acids in any order are suspected to be responsible for the antioxidative and hypotensive effect. Alcalase base hydrolysates from both batches has shown highest ACE inhibitory effect, although there is a need for further refinement in the procedure. The degree of hydrolyzation and yield have shown no significant different between enzyme-based hydrolysates.
Result from this thesis corroborate the developing knowledge on the therapeutic and nutritional attribute of the marine mesopelagic fish. Based on the yeild, degree of hydrolyzation, and bioactivity, endogenous enzyme are very promiscing and can potentially be tuned for commercial application | |
