DEVELOPMENT AND CHARACTERIZATION OF MONOCLONAL-ANTIBODIES THAT DIFFERENTIATE BETWEEN POTATO AND TOMATO GLYCOALKALOIDS AND AGLYCONS

A series of monoclonal antibodies (Mabs) that bind the potentially toxic glycoalkaloids and the corresponding aglycons found in potato (Solanum tuberosum) and tomato (Lycopersicon esculentum) has been developed. Most of these Mabs differentially bind solanidine versus the potato glycosides alpha-solanine and alpha-chaconine. Some bind solanidine, alpha-solanine, and alpha-chaconine with nearly equal affinity. Others bind only solanidine, and one binds the tomato glycoside alpha-tomatine and the corresponding aglycon, tomatidine. Fifty percent inhibition of control values in a competition ELISA ranged from 2.5 to 1000 ppb. Specificity and cross-reactivity are discussed in relation to three-dimensional, computer-generated molecular models of selected alkaloids. Results of analyses of potato samples by both the ELISA and an HPLC method are given and discussed. The data suggest that these antibodies provide a basis to develop sensitive, rapid, and inexpensive immunoassays for these alkaloids in plants, processed foods, and body fluids and tissues.