Production of antioxidant and ACE-inhibitory peptides from Kluyveromyces marxianus protein hydrolysates: Purification and molecular docking

• Published in: Yàowu shi͡p︡in fenxi 2018-04, Vol.26 (2), p.696-705
• Main Authors: Mirzaei, Mahta, Mirdamadi, Saeed, Ehsani, Mohamad Reza, Aminlari, Mahmoud
• Format: Article
• Language: English
• Subjects: ACE inhibitory; Amino Acid Sequence; Amino acids; Angiotensin-Converting Enzyme Inhibitors - chemistry; Angiotensin-Converting Enzyme Inhibitors - isolation & purification; Angiotensin-Converting Enzyme Inhibitors - metabolism; Antioxidant; Antioxidants; Antioxidants - chemistry; Antioxidants - isolation & purification; Antioxidants - metabolism; Bioactive peptides; Blood pressure; Chromatography; Chymotrypsin; Enzymes; Fractionation; High performance liquid chromatography; Humans; Hydrogen bonds; Hydrolysates; K. marxianus; Kluyveromyces - chemistry; Kluyveromyces - metabolism; Kluyveromyces marxianus; Liquid chromatography; Molecular chains; Molecular docking; Molecular Docking Simulation; Molecular Sequence Data; Original; Peptide Mapping; Peptides; Peptides - chemistry; Peptides - isolation & purification; Peptides - metabolism; Peptidyl-Dipeptidase A - chemistry; Protein hydrolysate; Protein Hydrolysates - chemistry; Protein Hydrolysates - isolation & purification; Protein Hydrolysates - metabolism; Protein purification; Proteins; Trypsin; Ultrafiltration
• ISSN: 1021-9498; 2224-6614
• DOI: 10.1016/j.jfda.2017.07.008

Kluyveromyces marxianus protein hydrolysates were prepared by two different sonicated-enzymatic (trypsin and chymotrypsin) hydrolysis treatments to obtain antioxidant and ACE-inhibitory peptides. Trypsin and chymotrypsin hydrolysates obtained by 5 h, exhibited the highest antioxidant and ACE-inhibitory activities. After fractionation using ultrafiltration and reverse phase high performance liquid chromatography (RP-HPLC) techniques, two new peptides were identified. One fragment (LL-9, MW = 1180 Da) with the amino acid sequence of Leu-Pro-Glu-Ser-Val-His-Leu-Asp-Lys showed significant ACE inhibitory activity (IC50 = 22.88 μM) while another peptide fragment (VL-9, MW = 1118 Da) with the amino acid sequence of Val-Leu-Ser-Thr-Ser-Phe-Pro-Pro-Lys showed the highest antioxidant and ACE inhibitory properties (IC50 = 15.20 μM, 5568 μM TE/mg protein). The molecular docking studies revealed that the ACE inhibitory activities of VL-9 is due to interaction with the S2 (His513, His353, Glu281) and S′1 (Glu162) pockets of ACE and LL-9 can fit perfectly into the S1 (Thr345) and S2 (Tyr520, Lys511, Gln281) pockets of ACE. [Display omitted] •Yeast protein hydrolysates were prepared by sonicated-enzymatic hydrolysis.•Antioxidant and ACE-inhibitory activity of yeast protein hydrolysates were evaluated.•Ultrafiltration and RP_HPLC techniques were used for purification of bioactive peptides.•Two antioxidant and ACE-inhibitory peptides (LL-9 and VL-9) were identified.•The molecular docking studies revealed that the ACE inhibitory activities of peptides are due to interaction with the active site of enzyme.