Submitted to: American Peanut Research and Education Society Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 10/11/2005
Publication Date: 12/1/2005
Citation: Chung, S., Champagne, E.T. 2005. Reducing the allergenic properties of peanut extracts by removing peanut allergens with phytic acids. American Peanut Research and Education Society Abstracts. 118 Interpretive Summary:
Technical Abstract: People are allergic to peanuts because peanuts contain proteins called allergens. Removing these proteins from a peanut kernel or extract is thought to help reduce or prevent peanut allergy. Phytic acid, which functions as the chief storage form of phosphate and inositol in mature seeds, can chelate metals and form complexes with proteins in the presence of calcium. In this study, we hypothesized that phytic acid can form complexes with the peanut allergens in the extracts, and thus, reduce the allergenic properties of extracts after removal of the complexes. To support our hypothesis, we treated peanut extracts (proteins at 5 mg/mL) with different concentrations of phytic acid (0.5-5 mM) under different pH conditions (pH 3, 7, 8.5) for 10 minutes, and then centrifuged. The resultant supernatants were then subjected to SDS-PAGE and inhibition ELISA, in which the allergenic properties of supernatants, or their bindings to IgE antibodies from a pooled serum of peanut-allergic individuals, were determined. Results showed that two major peanut allergens, namely Ara h 1 and Ara h 2, were precipitated by phytic acid (2-5 mM), while other proteins remained in the extract. The precipitation occurred only at pH 3 and 7, but not at pH 8.5. Overall, the phytic-treated extracts with precipitates removed had a lower IgE binding, or allergenic property, than the untreated. We concluded that phytic acids precipitated two major peanut allergens under acidic and neutral conditions, and thus, reduced the allergenic properties of the peanut extracts after removal of the precipitates.