The production of collagen type I hydrolyzate derived from tilapia (Oreochromis sp.) skin using thermoase PC10F and its in silico analysis

The main focus of this study was to produce the angiotensin-I converting enzyme (ACE) inhibitory peptides from collagen type I using new combination of Thermoase PC10F and tilapia skin as a protein collagen source. In silico evaluation of amino acids profile of collagen type I, ACE-inhibitory peptides and sensory profile of the hydrolyzate were performed using Protparam and BIOPEP, respectively, to initially predict the potential peptide produced. Hydrolysis conditions were studied based on the best preliminary design of degree hydrolysis (DH) using o-phthalaldehyde (OPA) method. The temperature of 60°C, pH of 5 and an enzyme to substrate ratio of 1:100 were observed as the best conditions to obtain the highest DH using Thermoase PC10F. Peptide chain length (PCL) showed a proportional decrease as DH increased. In silico study of alpha 1 and alpha 2 collagen type I indicated a significant amount of glycine and proline, which are known to stabilize the collagen structure. The profile of potential biological activity suggested that 247 ACE-inhibitory peptides could be obtained from the parent protein sequence of collagen type I alpha 1 and alpha 2. In silico hydrolysis by thermolysin is believed to release potent theoretical peptides with IC50 less than 5 μM for both collagen type I subunits with a high number of occurrences. Further analysis on its potential sensory peptides had shown that both alpha 1 and alpha 2 contained mainly sweet amino acid, bitter peptides, and bitter amino acids.