ABSTRACT
Vegetables are rich source of protein, dietary fiber, complex carbohydrates, resistant starch and a number of vitamins and minerals, namely foliate, potassium, selenium and zinc. In addition to the macronutrients, they contain a wide variety of anti-nutritional compounds such as toxic amino acids, saponins, cyanogenic glycosides, tannins, phytic acid, oxalates, goitrogens such as glucosinolates lectins, protease inhibitors, chlorogenic acid and amylase inhibitors. Cucurbits contain chemical compounds known as terpenoids that are also responsible for flavour and scent. Cruciferous vegetables, such as bokchoy, broccoli, Brussels sprouts, cabbage, cauliflower, horseradish, kale, kohlrabi, mustard, radish, rutabaga, turnip and watercress, are rich sources of glucosinolate precursors of isothiocyanates. Protease inhibitors are the most commonly encountered class of antinutritional factors of plant origin. The protein inhibitors of hydrolases present in legume vegetables are active against proteases, amylases, lipases, glycosidases and phosphatases. The major polyphenolic compounds of legume vegetables consist mainly of tannins, phenolic acids and flavonoids.
