title: Purification, activity and sequence of angiotensin I converting enzyme inhibitory peptide from alcalase hydrolysate of peanut flour.
abstract: Peanut hydrolysate obtained after 6 h of digestion by Alcalase was used to isolate angiotensin I converting enzyme (ACE) inhibitory peptides. After centrifugation and ultrafiltration through a 0.2 microm nylon filter, the hydrolysate was filtered through the polyethersulfone membrane with a molecular weight cutoff (MWCO) of 10 kDa. The resulting permeate was then separated by primary reverse-phase high performance liquid chromatography (RP-HPLC). Eluate was divided into six major fractions according to eluation time. The fraction with eluting time 50-60 min showed the most potent ACE inhibition and was subjected to further purification by the secondary RP-HPLC. Four peaks were found to have strong ACE inhibitory activities, and their IC(50) values were determined. Peptide mass for the most potent peak was obtained by matrix-assisted laser desorption and ionization (MALDI), and sequence was determined by MALDI tandem TOF-TOF (time-of-flight) mass spectrometer (MS/MS) to be Lys-Ala-Phe-Arg.
authors.affiliation: Department of Food Science and Technology, University of Georgia, 1109 Experiment Street, Griffin, Georgia 30223-1797, USA.
authors.forename: Cuie
authors.initials: C
authors.lastname: Guang
authors.forename: Robert D
authors.initials: RD
authors.lastname: Phillips
mesh_terms: D000806:Angiotensin-Converting Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D010367:Arachis / Q000737:chemistry*; D005433:Flour / Q000032:analysis*; D006868:Hydrolysis; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism*; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism; D020539:Sequence Analysis, Protein; D013381:Subtilisins / Q000737:chemistry
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D010455:Peptides; D007703:Peptidyl-Dipeptidase A; D013381:Subtilisins