ARS | Publication request: Pilot scale production of angiotensin I-converting enzyme (ACE) inhibitory peptides from aflatoxin contaminated peanut meal

Submitted to: American Chemical Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: March 23, 2011
Publication Date: March 23, 2011
Citation: White, B.L., Oakes, A.J., Shi, X., Price, K.M., Sanders, T.H., Davis, J.P. 2011. Pilot scale production of angiotensin I-converting enzyme (ACE) inhibitory peptides from aflatoxin contaminated peanut meal. American Chemical Society Abstracts. 1.

Technical Abstract: Peanut meal (PM) is the high protein (45-50%) by-product remaining after commercial extraction of peanut (Arachis hypogaea L.) oil. Applications of PM are limited to feeds and fertilizers because it typically contains a high concentration of aflatoxin. Recently, our lab has developed a process to reduce aflatoxin concentrations below the USDA action level for human consumption (20 ppb), while simultaneously hydrolyzing and extracting peptides with potential bioactive properties. In this work, the process has been scaled- up, and the resulting hydrolysates were evaluated for ACE inhibitory activity. Peanut meal dispersions were hydrolyzed with Alcalase in the presence of sodium bentonite clay. A decanter was used to separate the liquid stream from the wet solids cake. Samples were taken throughout processing for determination of aflatoxin concentration. The liquid stream was further purified by centrifugation, re-addition of clay, and ultrafiltration prior to testing for ACE inhibitory activity. After further purification, aflatoxin concentrations in liquid hydrolysates treated with clay were reduced below 20ppb. There were no significant differences in ACE inhibition among clay type or amount. The 4% AB20 hydrolysate had an IC50 value of 297.5 µg/mL. After ultrafiltration, the fraction that exhibited the highest inhibitory activity was the <3 kDa fraction (IC50 = 113.0 µg/mL), indicating that low molecular weight peptides are more affective ACE inhibitors than larger ones. These findings indicate that Alcalase hydrolysates of peanut meal may have health promoting effects, in particular blood pressure regulation, and may be explored as a possible functional ingredient. However, further research is required to determine its effects in vivo.