Controlled enzymatic hydrolysis of pollen protein as promising tool for production of potential bioactive peptides

In the present study, response surface method was used to optimize hydrolysis condition to generate potential bioactive peptides from pollen protein using pepsin (pepsin hydrolysated pollen—PHP) and trypsin (trypsin hydrolysated pollen—THP). Then PHP and THP prepared under optimized conditions were analyzed by size-exclusion chromatography. The fractions possessing the maximum ACE-inhibitory, DPPH radical scavenging, and ferric-reducing power were further purified by RP-HPLC. A heterogeneous composition of hydrophobic and hydrophilic peptides in both fractions was obtained. Finally, peptide sequences in active fractions of PHP and THP were identified by mass spectrometry in tandem. All the identified peptides had herbal protein origins. These were 6–21 amino acids in length, and Glycine and Alanine were two main hydrophobic amino acids present in their sequences. The results proved that using controlled enzymatic hydrolysis of pollen protein is possible to generate bioactive peptides with high ACE-inhibitory and antioxidant activity in final product. Practical applications: Pollen is well-known as an interesting protein source. Compared to other types of hydrolysis, enzymatic hydrolysis of vegetable proteins has few or no undesirable side reactions or products. In this study, controlled enzymatic hydrolysis of pollen protein was applied as a suitable method to produce bioactive peptide. The results proved that using controlled enzymatic hydrolysis of pollen protein is possible to generate bioactive peptides with high ACE-inhibitory and antioxidant activity in final product. This product can be used as functional and health promoting ingredient in different food formulations.
This work was financially supported by the Ministry of Science, Research and Technology of Iran, Grant AGL2014‐57367‐R and FEDER funds from the Spanish Ministry of Economy, Industry, and Competitiveness. Ramón y Cajal postdoctoral contract of LM is also acknowledged. MS/MS analysis was conducted in SCSIE University of Valencia Proteomics Unit (Spain) which is registered in ISCIII ProteoRed Proteomics Platform.