Analysis of Bioactive Peptides from Spirulina and Microalgae

Spirulina and microalgae are sources of vitamins, proteins, and bioactive compounds that are beneficial as health supplements. This research studies the protein hydrolysates obtained by digesting proteins extracted from five algae: Spirulina platensis strain C1 and BP, Nanochloropsis sp., Isochrysis sp. and Chaetoceros muelleri using pepsin enzyme. Peptide sequences of hydrolysates from the five algae were analyzed by using Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS). Then, bioactivity profiles of the peptides sequences were compared with a database of bioactive peptides by using the SmartBioPep platform. The results revealed that bioactive peptides of protein hydrolysates from five algae were found such as Angiotensin-Converting Enzyme (ACE) inhibitors, Dipeptidyl Peptidase IV (DPPIV) inhibitors, and Antioxidants, which are related to blood pressure reduction, associated with diabetes treatment, and exhibited antioxidant properties, respectively. Then, the bioactivity was tested by analyzing ACE inhibitory activity, DPPIV inhibitory activity, and Antioxidant activity. The results showed that bioactive peptides from protein hydrolysates of the five algae inhibited ACE activity and DPPIV activity at approximately 93-98%, and 85-99%, respectively, whereas exhibited Antioxidant activity with a Total Antioxidant Capacity (TAC) of 0.23-0.93 mM UAE. The results indicate that peptides produced from the five algae species are effective to use as nutraceutical.