Corn Distillers Solubles as a Plant-Based Bioresource for Proteins and Bioactive Peptides: Current Status and Bioprospects- a Critical Review

ABSTRACTThe demand for plant-based proteins is increasing at a rapid rate in the modern era. Hence, finding a new source of plant proteins might fulfill such requirements. Corn distilleries generate various protein-containing by-products, for instance, an undervalued and less explored corn distillers solubles (CDS). The CDS was reviewed to assess its potential as a new source of proteins and bioactive peptides. This review summarizes the current understanding of CDS proteins, with an emphasis on their composition, characteristics, quality, and bioactive peptides for cost-effective applications. Finally, several industrial applications of proteins and protein hydrolysates of CDS have been discussed, as well as the destiny of these products in terms of restrictions, barriers, future research paths, and problems. The literature showed that proteins of CDS were glycated to some extent due to the multiple evaporation steps employed in distilleries. To the best of the author's knowledge, the influence of yeast on the quality and quantity of CDS proteins has not been studied comprehensively. The digestibility of CDS proteins has not been clearly explicated. Enzymatic hydrolysis of protein concentrate from CDS implied its potential as protein hydrolysates comprising antioxidant capacity, dipeptidyl peptidase 4 inhibition and angiotensin-converting enzyme inhibition as the prime activities.KEYWORDS: Corn proteinprotein hydrolysateACEantioxidantenzymatic hydrolysis Abbreviations CGM=corn gluten mealDDGS=distillers dried grains with solublesCDS=corn distillers solublesMw=molecular weightAAs=amino acidsSDS=PAGE: sodium dodecyl sulfate-polyacrylamide gelCTS=corn thin stillagePF=protein fractionPHs=protein hydrolysateFAN=free amino nitrogenDH=degree of hydrolysisACE=angiotensin converting enzymeCE-MS=capillary electrophoresis mass spectrometryFPLC=fast protein liquid chromatographyACE-ia=angiotensin converting enzyme inhibitory activityDPP4-ia=dipeptidyl peptidase 4 inhibitory activityPC=protein concentrateRSA=radical scavenging activitySEC=size exclusion chromatographyRP-HPLC=reversed-phase high-performance liquid chromatographyDPPH=1,1-Diphenyl-2-PicrylhydrazylABTS+=2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic) acidAcknowledgmentsThis work was supported by Biofuel Net Canada; Ontario Ministry of Agriculture, Food and Rural Affairs, Guelph Ontario, IGPC Ethanol Inc., Aylmer, Ontario, Canada; Shrimp Canada, 67 Watson Rd. S (Unit - 2), Guelph, Ontario, N1L 1 E3, Canada.Disclosure statementNo potential conflict of interest was reported by the authors.CRediT authorship contribution statementSonu Sharma: Conceptualization, Methodology, Investigation, Data curation, Formal analysis, Visualization, Writing – original draft. Aneela Hayder: Analysis, Writing – original draft. Ranjan Pradhan: Review & editing, Supervision. Annamalai Manickavasagan: review & editing, Supervision. Mahendra Thimmanagari: Writing – review & editing. Singam Suranjoy Singh: Analysis, Writing – original draft. Adya Aiswarya Dash: Analysis, Writing – original draft. Animesh Dutta: Writing – review & editing, Supervision, Resources.Additional informationFundingThe work was supported by the BioFuelNet Canada [GRANT #: 054182].