Analysis of potato glycoalkaloids by a new ELISA kit

Steroidal glycoalkaloids are naturally occurring compounds present in solanaceous plants including potatoes. They are reported to be toxic to animals and humans. The recognition of their potential toxicity has led to implementation of guidelines limiting glycoalkaloid content. The effectiveness of these guidelines is dependent upon reliable analytical methods for their analysis. The objective of this study was to develop a simple, rapid, and inexpensive immunoassay for potato glycoalkaloids that correlates with HPLC. This was successfully demonstrated with various potato samples, including eight fresh potato varieties; potato flesh, peel, sprouts, and leaves; and processed products such as French fries, chips, and skins. Storage of the ELISA kit in a refrigerator for >3 months did not affect its effectiveness. The use of a stable, accurate, and highly sensitive ELISA kit should facilitate (a) development of standard protocols for handling and sampling of potatoes to minimize pre- and postharvest glycoalkaloid formation; (b) analysis of foliar glycoalkaloids, thus saving plant breeders considerable time, effort, and cost; (c) marketing potatoes at lower cost; (d) measurement of the metabolism and distribution of glycoalkaloids in animals and humans; and (e) assurance to the consumer of eating a good quality potato.