Allergy Asthma Immunol Res.  2012 May;4(3):157-160. 10.4168/aair.2012.4.3.157.

Changes in Major Peanut Allergens Under Different pH Conditions

• Kim J
• Lee J
• Seo WH
• Han Y
• Ahn K
• Lee SI

• KMID: 2167068
• DOI: http://doi.org/10.4168/aair.2012.4.3.157

Abstract

Regional dietary habits and cooking methods affect the prevalence of specific food allergies; therefore, we determined the effects of various pH conditions on major peanut allergens. Peanut kernels were soaked overnight in commercial vinegar (pH 2.3) or acetic acid solutions at pH 1.0, 3.0, or 5.0. Protein extracts from the sera of seven patients with peanut-specific IgE levels >15 kUA/L were analyzed by SDS-PAGE and immunolabeling. A densitometer was used to quantify and compare the allergenicity of each protein. The density of Ara h 1 was reduced by treatment with pH 1.0, 3.0, or 5.0 acetic acid, or commercial vinegar. Ara h 2 remained largely unchanged after treatment with pH 5.0 acetic acid, and was decreased following treatment with pH 1.0, 2.3, or 3.0 acetic acid. Ara h 3 and Ara h 6 appeared as a thick band after treatment with pH 1.0 acetic acid and commercial vinegar. IgE-binding intensities to Ara h 1, Ara h 2, and Ara h 3 were significantly reduced after treatment with pH 1.0 acetic acid or commercial vinegar. These data suggest that treatment with acetic acid at various pH values affects peanut allergenicity and may explain the low prevalence of peanut allergy in Korea.

Keyword

Acetic acid; allergens; Ara h 1 allergen; Ara h 2 allergen; Ara h 3 allergen; peanuts

MeSH Terms

Acetic Acid
Allergens
Arachis
Cooking
Electrophoresis, Polyacrylamide Gel
Food Habits
Humans
Hydrogen-Ion Concentration
Immunoglobulin E
Korea
Peanut Hypersensitivity
Prevalence
Acetic Acid
Allergens
Immunoglobulin E

Figure

• 

  Fig. 1 SDS-PAGE analysis of peanut proteins at various pH values (up) and their optical density (down). Raw peanuts (lane A), peanuts after commercial vinegar treatment at pH 2.3 (lane B), and peanuts after treatment with pH 1.0, 3.0, and 5.0 acetic acid solutions (lanes C, D, and E, respectively) are shown. Molecular weight standards are shown in lane M.

• 

  Fig. 2 Detection of anti-peanut-specific IgE at various pH values (up) and their optical density (down) by immunoblotting. Raw peanuts (lane A), peanuts after commercial vinegar treatment at pH 2.3 (lane B), and peanuts after treatment with pH 1.0, 3.0, and 5.0 acetic acid solutions (lanes C, D, and E, respectively) are shown. Molecular weight standards are shown in lane M.

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