By-products from salmon production contain bioactive peptides which among other things could have a positive effect on hypertension, type 2 diabetes and oxidative stress. This is one of the findings from a PhD project from the National Food Institute, Technical University of Denmark, Further research is needed to identify the specific components that have the health-promoting effects, with a view to possible use in eg functional foods and pharmaceutical products.
It has long been known that fatty fish are good for health because of their high content of omega-3 fatty acids. There has been an increased interest in recent years in the bioactive peptides that are also found in fish and fish protein, which possess a broad spectrum of health-promoting functions, such as antioxidant, antihypertensive, antimicrobial, anticancer and type 2 diabetes inhibiting.
Fish are able to live in environments where there are large amounts of bacteria in the water. This is probably because they are equipped with a special biodefence, consisting among other things of bio-components such as bioactive peptides, which enables them to fight disease-causing organisms. Studies have also shown that fish proteins contain several sequences that are bioactive when released by enzyme degradation.
Bioactive peptides in fish by-products
In her PhD project at the National Food Institute Susan Skanderup Falkenberg has studied different naturally occurring bioactive compounds in various types of fish tissue. She also examined whether health-promoting peptides can be generated from salmon using digestive enzymes to break down protein from belly flap muscle and skin from the fish.
Laboratory tests identified three types of bioactivities: One that can inhibit a blood pressure-regulating enzyme, one that can inhibit an enzyme involved in insulin regulation, and one that has an antioxidant effect.
Enzymes that are naturally present in people’s digestive system were used in the tests. Through her research Susan Skanderup Falkenberg has therefore not only demonstrated how value can be added to salmon by-products through enzymatic degradation, but also created new knowledge about bioactive substances which can be released when people digest a piece of salmon they have eaten.
Knowledge can benefit the food and pharmaceutical industries
It was not possible in the project to identify the bioactive components responsible for one specific bioactivity. Further research is needed to identify the specific bioactive components that might be used to develop the ingredients in functional foods or pharmaceutical products.
Read more
Read the English summary of Susan Skanderup Falkenberg’s PhD-thesis: Discovery and characterization of novel bioactive peptides from marine secondary products (pdf).
A copy of the PhD thesis is available at the National Food Institute. Once the thesis articles have been published the entire thesis will become accessible on www.food.dtu.dk. Please send an email to food@food.dtu.dk if you wish to be notified when this happens.