Production and characterization of rabbit polyclonal antibodies to almond (Prunus dulcis L.) major storage protein

Rabbits were immunized with purified almond major protein (AMP), the primar y storage protein in almonds. Rabbit anti-AIMP polyclonal antibodies (PA) c ould detect AMP when as little as 1-10 ng/mL were used to coat microtiter p lates in a noncompetitive enzyme Linked-immunosorbent assay (ELISA). Compet itive inhibition ELISA assays detected the AMP down to 300 ng/mL. PA recogn ized the AMP in protein extracts from all U.S. major marketing cultivars of almonds (Mission, Neplus, Peerless, Carmel, and Nonpareil) with specific r eactivity of 52.6-75% as compared to that of the AMP alone. Immunoreactivit y of protein extracts prepared from commercial samples of blanched almonds, roasted almonds, and almond paste was respectively reduced by 50.0%, 56.6% , and 68.4% (noncompetitive ELISA) when compared to the immunoreactivity of the AMP. Moist heat (121 degrees C, 15 min) pretreatment of the AMP reduce d the PA reactivity by 87% (noncompetitive ELISA). Exposing AMP to pH extre mes (12.5 and 1.5-2.5) caused a 53% and 57% reduction in PA reactivity, res pectively (noncompetitive ELISA). PA showed some cross-reactivity with the cashew major globulin, and to a lesser extent, the Tepary and Great Norther n bean major storage protein (7S or phaseolin). The presence of almonds in a commercial food was detected using PA in a competitive ELISA.