Evaluation of the relationship of molecular weight of bioactive peptides resulting from enzymatic hydrolysis of Vanami shrimp (Litopenaeus vannamei) head and shell with their antibacterial, antioxidant and functional properties

Abstract

The current research aimed to determine the relationship between the molecular weight of bioactive peptides produced from Vanami shrimp wastes with their antibacterial, antioxidant activity, and functional properties. For this purpose, after performing the hydrolysis process, using ultrafiltration, peptides with a molecular weight of less than 3, between 3 and 10, and more than 10 kDa were separated and used for various tests. According to the results, peptides with a molecular weight of 3 to 10 kDa showed the highest growth inhibitory activity of Bacillus cereus, Escherichia coli, and Staphylococcus aureus (p< 0.05). The highest solubility and water holding capacity were related to peptides with molecular weight less than 3 kDa (p<0.05). Among different molecular weights, the maximum emulsifying activity and emulsion stability indices were measured in peptides with a molecular weight between 3 and 10 kDa (p<0.05). The strongest peptides in terms of foaming activity and foam stability index as well as oil absorption capacity were peptides with a molecular weight of more than 10 kDa (p<0.05). The results of the evaluation of the antioxidant activity (Free radical scavenging activity of DPPH and ABTS) of peptides showed peptides with a molecular weight of less than 3 kDa have the highest antioxidant properties (p<0.05). It was concluded that the properties of bioactive peptides change considerably under the influence of molecular weight and each of the peptides in a particular molecular weight has more properties and efficiency.

Keywords

• shrimp wastes
• bioactive peptides
• molecular weight
• antibacterial activity