Tomatine

Tomatine is a glycoalkaloid found in the stems and leaves, and to a lesser extent in the fruits, of tomatoes (Solanum lycopersicum). It is a defensive natural product against pests and diseases. Tomatine is also found in other members of the Solanaceae family, which includes plants such as potatoes and eggplants.

Chemical Structure

Tomatine is a steroidal glycoalkaloid, which means it is composed of a steroid backbone bound to a sugar molecule. The steroid part of the molecule is solanidine, and the sugar part is a tetrasaccharide made up of two molecules of glucose, one of galactose, and one of xylose.

Biosynthesis

The biosynthesis of tomatine involves several steps. It begins with the conversion of cholesterol to solanidine by a series of enzyme-catalyzed reactions. The solanidine is then glycosylated, or attached to a sugar molecule, to form tomatine.

Toxicity

Tomatine is toxic to some insects, fungi, and bacteria, which helps protect the tomato plant from these pests. However, it is generally considered safe for humans to consume in the amounts present in ripe tomatoes. The concentration of tomatine decreases as the tomato ripens, so green tomatoes contain higher levels of tomatine than ripe ones.

Health Benefits

Some studies suggest that tomatine may have health benefits for humans. It has been shown to have anti-inflammatory and antioxidant effects, and it may also have anticancer properties. However, more research is needed to confirm these potential benefits and to understand how tomatine works in the human body.

See Also

• Solanine
• Alkaloids
• Glycoalkaloids