Food Glycoalkaloids: Distribution, Structure, Cytotoxicity, Extraction, and Biological Activity

Abstract

Glycoalkaloids (GA), generally occur as plant steroidal glycosides, are secondary metabolites produced in the leaves, flowers, roots, and edible parts including sprouts and skin of the plants of Solanaceae family. Many of the plants in this family have been stable parts of human diets for centuries, and thus, the occurrence of these compounds has been extensively studied mainly due to concerns regarding their toxicity. GAs are produced by plants as a resistance to challenges such as insects and pests but may also produce concentration-dependent toxic effects in humans. Postharvest conditions such as light, temperature, humidity, and processing conditions may also affect GA content in edible plants producing them. Since these compounds also possess biological properties such as anti-inflammatory, antimicrobial, and anticarcinogenic activities, it could be a useful strategy to use novel extraction techniques to maintaining bioactivities after extraction and simultaneously to reduce toxicity in the source plants. This chapter aims to describe alkaloids especially GAs commonly occurring in foods, their structure and toxicity, and postharvesting practices which influence alkaloid content and utilization of conventional and novel technologies to extract food alkaloids.