ABSTRACT
The most common phytosterols in plant lipids are sitosterol, campesterol, and stigmasterol, belonging to the group known as 4-desmethylsterols (1). Brassicasterol, another 4-desmethylsterol, is present in considerable amounts in the lipids of Cruciferae (1). In addition, some cereal lipids contain a considerable proportion of the saturated counterpart of plant sterols (phytosterols), generally called stanols (2). The formation, analysis, occurrence, and biological effects of the oxidation products of cholesterol (COPs), the main sterol in animal lipids, have been extensively studied (3). However, research on these aspects with the corresponding phytosterol oxidation products (POPs) has been very limited (4-6). Based on limited number of studies on phytosterol oxidation it has been concluded that the main oxidation route is generally the same as that in cholesterol oxidation (7). Similarly, the analysis of POPs also follows the same procedures as in the case of COPs (5). In this chapter, pathways of phytosterol oxidation, results from the recent research in the area of analysis, and their occurrence of phytosterols in foods are reviewd. Analysis of POPs in biological samples is highlighted in Chapter 4 of this book.
