18B-32 |
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E. E. QUIST1, F. K. Saalia2, and R. D. Phillips2. (1) Dept. of Food Science and Technology, Univ. of Georgia, 1109 Experiment St., Griffin, GA 30223-1797, (2) Dept. of Food Science & Technology, Univ. of Georgia, 1109 Experiment St., 116 Melton Bldg., Griffin, GA 30223-1797 Hypertension is a major health issue. Bioactive peptides from both plant and animal sources have been shown to have physiological properties including antihypertensive activity. The degree of solubility and hydrolysis determine to a great extent the functionality of proteins. Angiotensin Converting Enzyme (ACE) inhibitory peptides prevent the formation of Angiotensin I to Angiotensin II, contributing to reduction in blood pressure. The objective was to identify, isolate and optimize bioactive peptides from proteolytic digests of both raw and processed defatted peanut flours, with antihypertensive effects against ACE. Defatted (1%) raw and roasted peanut flours were subject to 24 hours proteolytic hydrolysis using Pepsin-Pancreatin and Alcalase. The hydrolysates were evaluated for the degree of hydrolysis (DH) and confirmed using SDS-PAGE. The most hydrolyzed sample from each group was analyzed from ACE inhibitory activity. Hydrolysates with highest inhibitory activity were then analyzed using the HPLC from which fractions were collected and IC50 calculated. DH was higher for the Alcalase system than the Pepsin-Pancreatin system, and raw peanut proteins were hydrolyzed to a greater extent than roasted peanut, with 25% being the highest value recorded. ACE inhibitory activity increased with increasing DH. HPLC fractions revealed that the hydrophobic end of the chromatogram had more inhibitory power with IC50 values ranging up to approximately 100 ug/ml compared to approximately 12 ug/ml for a known ACE inhibitory peptide (pGlu-Trp-Pro-Arg-Pro-Gln-Ile-Pro-Pro). Amino acid analyses to identify the composition of the derived peptides is underway. Consuming peanut with potent ACE inhibitory peptides maybe effective in regulating blood pressure.
Session 18B, Food Chemistry: Antioxidant and bioactive agents
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |