Bioactive peptides and methods of producing and using the same

Abstract

Described herein are methods of identifying and releasing bioactive peptides from their full length proteins. The method involves (a) contacting the protein with a reducing agent, a sonication step, a high pressure processing step, a heating step, a fermentation step, or any combination thereof; and (b) contacting the protein after step (a) with a hydrolytic enzyme to produce the bioactive peptide. The bioactive peptides exhibit enhanced biological activity when compared to the parent protein. The bioactive peptides may be added to foodstuffs, a medication, or to any potable, ingestible, or edible compositions.

What is claimed: 
     
         1 . A method for producing a bioactive peptide from a protein comprising:
 (a) contacting the protein with a reducing agent, a sonication step, a high pressure processing step, a heating step, a fermentation step, or any combination thereof; and   (b) contacting the protein after step (a) with a hydrolytic enzyme to produce the bioactive peptide.   
     
     
         2 . The method of  claim 1 , wherein the protein comprises at least one disulfide bridge. 
     
     
         3 . The method of  claim 1 , wherein the protein comprises between 2 and 50 disulfide bridges. 
     
     
         4 . The method in any of  claim 1 , wherein the protein is an animal protein, a plant protein, a microbial protein, a fungal protein, an egg protein or any combination thereof. 
     
     
         5 . The method of  claim 1 , wherein the protein is from the transferrin family. 
     
     
         6 . The method of  claim 1 , wherein the protein is ovotransferrin or an ovotransferrin isoform. 
     
     
         7 . The method of  claim 1  wherein the reducing agent comprises a thiol compound. 
     
     
         8 . The method of  claim 1 , wherein the reducing agent comprises β-mercaptoethanol, dithiothreitol, tris(2-carboxyethyl)phosphine, mercaptoethylamine, thioredoxin reductase, ferrous ion, lithium aluminum hydride (LiAlH 4 ), nascent hydrogen, SO 2 , sodium amalgam, sodium borohydride (NaBH 4 ), stannous ion, sulfite compounds or any combination thereof. 
     
     
         9 . The method of  claim 1 , wherein the sonication step comprises subjecting the protein to 1 to 100 pulses at 20 kHz to 120 kHz for 2 seconds to 600 minutes. 
     
     
         10 . The method of  claim 1 , wherein the hydrolytic enzyme comprises pepsin, thermolysin, trypsin, chymotrypsin, pancreatin, or any combination thereof. 
     
     
         11 . The method of  claim 1 , wherein the hydrolytic enzyme comprises at least two enzymes, wherein the enzyme comprises pepsin, thermolysin, trypsin, chymotrypsin, pancreatin, or any combination thereof. 
     
     
         12 . The method of  claim 1 , wherein the protein is ovotransferrin and the bioactive peptide comprises an amino acid sequence comprising SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:10, SEQ ID NO:23. 
     
     
         13 . A hydrosylate produced by the method of  claim 1 . 
     
     
         14 . A mixture of peptides purified from the hydrosylate of  claim 19 . 
     
     
         15 . A composition comprising at least two different isolated peptides, wherein each isolated peptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:10, SEQ ID NO:23. 
     
     
         16 . A composition comprising a foodstuff, a medication, any potable, ingestible, or edible compositions comprising the hydrosylate of  claim 19 . 
     
     
         17 . The method of reducing or preventing high blood pressure in a subject comprising administering to the subject the hydrosylate of  claim 19  a mixture of peptides purified from the hydrosylate of  claim 19 , or composition comprising at least two different isolated peptides, wherein each isolated peptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:10, SEQ ID NO:23. 
     
     
         18 . The method of  claim 17 , wherein the subject has diabetes. 
     
     
         19 . A method for inhibiting or reducing the activity of angiotensin converting enzyme (ACE) comprising contacting a cell with the hydrosylate of  claim 19  a mixture of peptides purified from the hydrosylate of  claim 19 , or composition comprising at least two different isolated peptides, wherein each isolated peptide comprises an amino acid sequence selected from the group consisting of SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:10, SEQ ID NO:23.