ABSTRACT
Ana o 3 is an immuno-dominant cashew nut allergen. Four monoclonal antibodies to Ana o 3 (2H5, 6B9C1, 19C9A2, and 5B7F8) were characterized by ELISA and in silico modeling. The 2H5 antibody was the only antibody specific for cashew nut extract. In addition to cashew nut extract, the 6B9C1 and 19C9A2 antibodies recognized pistachio extract, and the 5B7F8 recognized pecan extract. All four antibodies recognized both recombinant Ana o 3.0101 and native Ana o 3. ELISA assays following treatment of purified Ana o 3 with a reducing agent indicated that the 6B9C1 and 19C9A2 antibodies likely recognize conformational epitopes, while the 2H5 and 5B7F8 antibodies likely recognize linear epitopes. In silico modeling predicted distinct epitopes for each of the anti-Ana o 3 antibodies. Screening extracts from 11 Brazilian cashew nut cultivars using all four antibodies showed slight differences in Ana o 3 bindings, demonstrating that these antibodies could identify cultivars with varying allergen content.
ABSTRACT
The study investigated the influence of atmospheric plasma processing on cashew nut composition as well as on its allergenicity. The cashew nuts were processed by low-pressure plasma, using glow discharge plasma (80â¯W and 50â¯kHz power supply). Anacardic acids and allergens were quantified by HPLC and immunoassay, respectively. Additionally, the overall composition was evaluated by 1H qNMR. Increases in amounts of anacardic acids (15:1, 15:2, and 15:3) and fatty acids (oleic, linoleic, palmitic and stearic) were detected after all process conditions, with 70.92% of total variance captured using 2 LVs. The total amount of anacardic acids increased from 0.7 to 1.2⯵g·mg-1 of nut. The major change was observed for anacardic acid (C15:3) with an increase from 0.2 to 0.55⯵g/mg of nut for the samples treated with a flow of 10â¯mL·min-1 and 30â¯min of processing. On the other hand, the amount of sucrose decreased, from 33 to 18â¯mg·g-1 of nut, after all processing conditions. Plasma processing of cashew nuts did not affect binding of either the rabbit anti-cashew or human cashew allergic IgE binding. Among the treatments, 10â¯min of plasma processing at flow rate of 30â¯mL·min-1 of synthetic air followed by 20â¯min at flow rate 5.8â¯mL·min-1 had the least effect on nut composition as a whole.