Method for extracting antibacterial peptides and albumin from pea whey wastewater

A method for extracting antibacterial peptides from pea whey wastewater, comprising following steps:

• centrifuging with the pea whey wastewater generated during pea protein processing as raw material;
• controlling temperature and exchanging heat to adjust temperature of the raw material;
• sequentially performing a microfiltrating, nanofiltration, ultrafiltration and secondary nanofiltration to obtain an albumin slurry;
• performing a multi-effect concentrating on the albumin slurry;
• adding an alkaline substances to adjust pH;
• sterilizing and drying to obtain the albumin;
• adding water to the albumin to obtain another albumin slurry, pretreating in water bath, cooling and stirring on a constant temperature magnetic stirrer, adding papain and dipping alkali solution to keep pH of enzymatic hydrolysate constant;
• boiling to inactivate enzyme after full enzymolysis and cooling, adjusting the pH to 7.0;
• centrifuging and concentrating supernatant by rotary evaporation, and sterilizing with a 0.22 μm syringe filter to obtain primary product of the antibacterial peptides;
• and
• passing the primary product of the antibacterial peptides through an extractor, which is cleaned and activated in advance with methanol aqueous solution and then cleaned and balanced by aqueous trifluoroacetic acid solution;
• sequentially passing the methanol aqueous solution and the aqueous trifluoroacetic acid solution through the extractor and collecting penetrating liquid, vacuum concentrating the penetrating liquid by a rotary evaporator to get concentrated antibacterial peptide solution, taking out the concentrated antibacterial peptide solution and freezing at −15° C., and drying the frozen antibacterial peptides in a vacuum freeze dryer to obtain purified antibacterial peptides;
• wherein PH value of the antibacterial peptides is 2.56 to 2.78, as measured by a pH meter;
• and
• an antibacterial peptide molecule contains glycine, cysteine, arginine, lysine, histidine, alanine, threonine, aspartic acid, leucine, phenylalanine, serine, glutamic acid, valine, methionine, or tyrosine.