Enzymatic Release and Characterization of Novel Bioactive Peptides from Milk Proteins

• Main Author: De Gobba, Cristian
• Format: Book
• Language: English
• Published: Department of Food Science, Faculty of Science, University of Copenhagen 2014
• Subjects: greenlandic
• Online Access: https://curis.ku.dk/portal/da/publications/enzymatic-release-and-characterization-of-novel-bioactive-peptides-from-milk-proteins(13022eeb-5c77-4481-9366-6281da160be4).html; https://soeg.kb.dk/permalink/45KBDK_KGL/1pioq0f/alma99122949645905763

Milk is considered the most complete food, providing most of the nutrients needed. Milk proteins are not only important for their function as a source of amino acids, but they are also a source of bioactive peptides. These are short amino acid sequences with different activities that have a positive impact on body functions or conditions and may ultimately influence health. Bioactivities such as ACE-inhibitory, antioxidant, opioid, antimicrobial and anti-inflammatory have been identified in milk derived peptides. The purpose of this project is to identify novel bioactive peptides (ACE-inhibitory, antioxidant and antimicrobial peptides) released from milk proteins by mean of enzyme-catalysed hydrolysis. Goat milk fractions (produced using microfiltration membranes) and bovine casein were used as substrates. The goat milk fractions (retentate, permeate and skimmed milk) were hydrolysed with two commercial enzymes. The bovine casein was hydrolysed using the supernatant of a Greenlandic bacterium (Arsukibacterium ikkense), produced in the NOVENIA project, which contains cold-active proteolytic enzymes. The hydrolysates were tested for the relevant bioactivities and active fractions were fractionated by semipreparative chromatographic methods in order to identify the major peptides responsible for the activity. A positive correlation between ACE-inhibitory activity and extent of hydrolysis and activity was seen with both substrates. The most active hydrolysates showed an IC50 similar to the most active milk protein hydrolysates made in other studies. Regarding radical scavenging activity, the bovine casein hydrolysates also showed a positive correlation between extent of hydrolysis and activity, although the difference between the unhydrolysed sample and the hydrolysates was less marked. The goat milk hydrolysates, instead, showed a difference between the fractions more than the degree of hydrolysis, the retentate being the most active radical scavenger regardless the degree of hydrolysis and enzyme used. Both ...