Natural Secondary Metabolites. Springer, Cham. (2023)
Sulfur (S) is an essential nutrient assimilated through the diet and incorporated into organic structures such as amino acids, coenzymes, and other bioactive compounds. Plants’ ability to regulate stress resistance via secondary metabolism has extended the interest in S-containing compounds, driven by their additional properties as bioactive molecules. Among plant families that produce S-compounds, the Brassicaceae, which includes broccoli, cabbage, and cauliflower, and the Liliaceae family, which includes garlic and onion, stand out. In recent years, the research has been focused on S-containing amino acids (mainly methionine and cysteine) and glucosinolates (GSLs) and their hydrolysis products like isothiocyanates but also in other S-containing compounds such as phytoalexins or cysteine sulfoxides. GSLs are becoming more popular because of their specific biological properties, including antioxidant, anti-inflammatory, or antimicrobial, among others. Accordingly, a diet rich in vegetables containing S-containing compounds has been associated with a lower risk of developing cancer, neurological diseases like Alzheimer’s, inflammatory bowel disease, cardiovascular diseases, several skin disorders, and obesity. Hence, S-metabolites can therefore be used as therapeutic and preventative components in functional foods and nutraceuticals, as well as cosmeceutical products. This chapter aims to revise the most important features related to sulfur metabolism and S-containing compounds from plant sources, with emphasis on their involvement in secondary metabolism, natural sources, structural classification, biological functions, and applications in human nutrition and health.
