Dual‐enzyme hydrolysis for preparation of ACE‐inhibitory peptides from sesame seed protein: Optimization, separation, and identification

Abstract

To prepare and identify ACE-inhibitory peptides originated from sesame seed protein, peptides with strong ACE-inhibitory activities were obtained via the optimization of protease and hydrolysis conditions, and these peptides were purified and identified by membrane separation, gel filtration, and liquid chromatography-mass spectrometry. Results showed that the dual-enzyme comprised alcalase and trypsin with the enzyme activity ratio of 3:7 was suitable to produce ACE-inhibitory peptides. The highest ACE-inhibitory activity of 98.10 ± 0.26% was obtained at the following parameters, pH 8.35, E/S ratio of 6,145 U/g, and hydrolysis time of 4.4 hr.ISGAQPSLR and VVISAPSK ranked the first and second ACE-inhibitory activity among 15 identified ACE-inhibitory peptides. Both peptides influenced ACE via binding with the S1 pocket, S2 pocket, and Zn 2+ ion. ISGAQPSLR even impacted the S1′ pocket. ISGAQPSLR and VVISAPSK acted as a competitive and noncompetitive inhibitor, respectively. ACE-inhibitory peptides derivated from sesame seed protein have potential applications in functional food. Practical applicationsAlthough sesame seed protein is proven as the precursor of ACE-inhibitory peptide, preparing ACE-inhibitory peptide from sesame seed protein is still suffering from insufficient information on hydrolysis condition and the peptide sequence. Therefore, the performance of the typical protease on preparing ACE-inhibitory peptide from sesame seed protein has been evaluated, the effect of the amino acid composition of sesame seed protein and cleavage specificity of protease on the generation of ACEinhibitory peptide has been investigated, hydrolysis conditions have been optimized, the peptide sequence has been identified to illuminate the effect of sesame seed protein fraction on the formation of ACE-inhibitory peptide and discuss the structural characteristics. ACE-inhibitory peptides originating from sesame seed protein could apply in functional food. It is promising for dual-enzyme hydrolysis to utilize in preparation of high-value bioactive peptides.

Targeted hydrolysis of native potato protein: A novel route for obtaining hydrolysates with improved interfacial properties

“…While Leu specificity was described by the manufacturer, Glu specificity was not. Nevertheless, this is in line with previous reports on Alc specificity (Doucet et al, 2003; Lu et al, 2021). These inconsistencies highlight a crucial aspect for successful application of the presented methodology.…”

“…* References: a (García- ), b (García-Moreno, Gregersen, et al, 2020, c (Yesiltas et al, 2021), andd (García-Moreno et al, 2021). ** End of protein sequence Alc has broad specificity and has been reported to cleave after a wide range of residues (Ala/Leu/Val/Phe/Tyr/Trp/Glu/Met/Ser/Lys) with varying claims throughout literature (Doucet, Otter, Gauthier, & Foegeding, 2003;Lei, Cui, Zhao, Sun-Waterhouse, & Zhao, 2014;Lu et al, 2021;Sbroggio, Montilha, Figueiredo, Georgetti, & Kurozawa, 2016). A similar lack of consensus for Neut specificity is also found, although varying reports on the broad specificity of Alc and Neut exist, an in silico analysis based on supplier specificity (Novozymes A/S) was performed.…”

Preparation of angiotensin I- converting enzyme (ACE) inhibitory peptides from Tieguanyin tea residue protein using two-step enzymatic hydrolysis

“…Thus, considering the production cost and e ciency, 2.5 h is selected as the central value of the time factor of the RSM. This conclusion was consistent with Xin Lu et al (Lu, 2021), who found that with the extension of time, the reaction becomes more and more su cient, and the ACE inhibition rate increases gradually, but the long-term enzymatic hydrolysis will hydrolyze the polypeptide into amino acids without ACE inhibition activity.…”

Characterization of bioactive peptides produced from green lentil ( Lens culinaris ) seed protein concentrate using Alcalase and Flavourzyme in single and sequential hydrolysis

“…The ACE‐inhibitory activity of LPC and LPH samples was measured using the HPLC hippuryl‐His‐Leu (HHL) substrate method described by Lu et al. (2021). The hippuric acid liberation amount from HHL was determined during the 30 min incubation at 37℃ with angiotensin I‐converting enzyme (from rabbit lung) in the presence (main sample) and absence (control) of LPC or LPH samples.…”

“…For instance, Alcalase as an endopeptidase cleaves the peptide bonds from the interior section of protein while the Flavourzyme as an endopeptidase and exopeptidase can break down the protein from interior and exterior (Xu, Galanopoulos, et al., 2020). Sequentially applying these enzymes or dual‐hydrolysis can produce peptides with higher DH or lower MWs and subsequently, amino acid composition and ACE‐inhibitory activity are altered (Lu et al., 2021). Sequential hydrolysis also has improved the bitterness of produced peptides from single hydrolysis.…”