triacilgliceróis

Triacylglycerols, also known as triglycerides, are the main constituents of body fat in humans and other animals, as well as vegetable fat. They are esters formed from one molecule of glycerol and three molecules of fatty acids. The glycerol backbone is a three-carbon alcohol, and each hydroxyl group of the glycerol is esterified with a fatty acid. The three fatty acids in a triacylglycerol molecule can be the same or different. If they are different, the position of each fatty acid on the glycerol backbone is designated as sn-1, sn-2, or sn-3.

Triacylglycerols are a major form of energy storage in organisms because they are highly reduced and can be stored in an anhydrous form. When metabolized, they yield more than twice the amount of energy per gram compared to carbohydrates or proteins. In animals, triacylglycerols are stored in adipocytes, specialized cells of adipose tissue. In plants, they are stored in seeds and fruits, providing energy for germination and growth.

The physical properties of triacylglycerols depend on the types of fatty acids they contain. Triacylglycerols with a high proportion of saturated fatty acids are typically solid at room temperature and are known as fats. Those with a high proportion of unsaturated fatty acids are typically liquid at room temperature and are known as oils. Digestion of triacylglycerols in the gut involves hydrolysis by lipases to release glycerol and fatty acids, which can then be absorbed and utilized for energy or rebuilt into new triacylglycerols.