Peptides with a similar antioxidant and ACE-inhibitory activity of royal jelly (RJ) generated from Alcalase hydrolysated pollen (AHP) were predicted by Response Surface Methodology (RSM). Later, AHP was prepared and deproteinised to be further analysed using size-exclusion chromatography (SEC). After SEC separation, fractions 49-57, 64-66 and 52-54 of AHP and fractions 43-55 of RJ that showed the highest ACE-inhibitory, DPPH radical scavenging and ferric-reducing power activities, were purified by RP-HPLC. After the separation of fractions 49-57 of AHP, fractions eluting at 3, 4, 5, 37 and 60 min and fractions eluting at 12 to 33 min showed ACE-inhibitory activity higher than 80% whereas fraction eluting at 34 min showed the highest DPPH scavenging activity. 195 peptide sequences were identified by nano-liquid chromatography and mass spectrometry in tandem (nLC-MS/MS). The origins of all identified peptides were herbal proteins and certain similarities with previously described bioactive sequences were discussed.

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In this research, the bee pollen protein hydrolysate was microencapsulated by spray drying using maltodextrin (MD), whey protein concentrate (WPC) and a mixture of both compounds. For this purpose, the bee pollen was hydrolysed by alcalase (enzyme concentration of 1.5%) at 50 C and pH 8 during 3.95 h, and then freeze-dried. The hydrolysed protein and wall materials were used in ratio of 1:10 (w/w). The wall materials included maltodextrin 2%, WPC 2%, as well as maltodextrin and WPC mixtures with 3:1 ratio. The resulting capsules were exposed to UV radiation for 48 h to accelerate the oxidation. The results showed that the capsule prepared using maltodextrin and WPC mixture showed the highest DPPH radical scavenging during exposure to UV radiation. Based on the FTIR spectroscopy results, the wall containing maltodextrin and WPC mixture showed the best performance in maintaining the chemical structure of hydrolysed protein. The SEM results indicated that the microcapsules prepared with WPC and maltodextrin mixture as wall material showed uniform and smoother wall than those prepared with maltodextrin alone. Finally, it was found that the maltodextrin and WPC mixture was the best wall with an appropriate protective capability for the microencapsulation of hydrolysed proteins and their protection against UV radiation.

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.