The Odor Growing Brussel Sprouts Use to Protect Themselves

Phytonutrients

• Brussels sprouts, like other cabbage family members, get most of their noticeable odors from glucosinolates. The plants make glucosinolates by processing elements and basic nutrients to manufacture new compounds in response to environmental factors like heat and light, attack by predators and infection by bacteria, fungi or other pathogens. Because compounds like glucosinolates are not necessary to the basic growth of the plant and occur in response to exterior causes, they are known as secondary metabolites or plant natural products.

Glucosinolates

• Glucosinolates are classified as organosulfates, or compounds rich in sulfur. The characteristic smell of boiled Brussels sprouts comes from the sulfur contained in glucosinolates. To make the chemicals Brussels sprouts uses for defesce, glucosinolates are acted upon by an enzyme, myrosinase, producing potent-smelling hydrogen sulfate and isothiocyanates. Hydrogen sulfate gives the bad smell to rotten eggs. The kinds of glucosinolates present in Brussels sprouts are sinigrin, progoitrin and glucobrassicin, all of them bitter-tasting.

Effects on Animals

• Glucosinolates have a natural insecticidal effect on insects. Cabbage butterflies are pests on Brussels sprouts. When lower leaves of Brussels sprouts are infested with cabbage butterfly caterpillars, aromatic volatiles of glucosinolates are produced from the upper leaves. The three specific glucosinolates found in Brussels sprouts are toxic to rats. When these products are contained in excess in animal feed, they can cause poisoning in cattle and symptoms of thyroid, liver and kidney toxicity in animals.

Effects on Humans

• Glucosinolates and the compounds that come from them have been shown to have anticancer effects. They inactivate carcinogens and eliminate them more quickly from the body. In the amounts contained in human diets, these compounds are beneficial and nontoxic. However, humans are very sensitive to bitter tastes. People can detect the presence of sinigrin at the concentration of 106 mg per liter. This leads to reluctance to eat vegetables such as Brussels sprouts, which is high in sinigrin. As a result, plant breeders have selected for milder-tasting strains of Brussels sprouts. Herein arises a dilemma. Although the Brussels sprouts taste better, the amounts of healthful phytonutrients are decreased, and the milder strain has a decreased natural defense system.