Science, Tech, Math › Science Name 3 Disaccharides List of Disaccharide Examples Share Flipboard Email Print This is a ball and stick model of sucrose, a dissacharide formed in plants from glucose and fructose. Laguna Design, Getty Images Science Chemistry Biochemistry Basics Chemical Laws Molecules Periodic Table Projects & Experiments Scientific Method Physical Chemistry Medical Chemistry Chemistry In Everyday Life Famous Chemists Activities for Kids Abbreviations & Acronyms Biology Physics Geology Astronomy Weather & Climate By Anne Marie Helmenstine, Ph.D. Chemistry Expert Ph.D., Biomedical Sciences, University of Tennessee at Knoxville B.A., Physics and Mathematics, Hastings College Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels. our editorial process Facebook Facebook Twitter Twitter Anne Marie Helmenstine, Ph.D. Updated January 28, 2020 Disaccharides are sugars or carbohydrates made by linking two monosaccharides. This occurs via a dehydration reaction and a molecule of water is removed for each linkage. A glycosidic bond can form between any hydroxyl group on the monosaccharide, so even if the two subunits are the same sugar, there are many different combinations of bonds and stereochemistry, producing disaccharides with unique properties. Depending on the component sugars, disaccharides may be sweet, sticky, water-soluble, or crystalline. Both natural and artificial disaccharides are known. Here is a list of some disaccharides, including the monosaccharides they are made from and foods containing them. Sucrose, maltose, and lactose are the most familiar disaccharides, but there are others. Sucrose (saccharose) glucose + fructoseSucrose is table sugar. It is purified from sugar cane or sugar beets. Maltose glucose + glucoseMaltose is a sugar found in some cereals and candies. It is a product of starch digestions and may be purified from barley and other grains. Lactose galactose + glucoseLactose is a disaccharide found in milk. It has the formula C12H22O11 and is an isomer of sucrose. Lactulose galactose + fructoseLactulose is a synthetic (man-made) sugar that is not absorbed by the body but is broken down in the colon into products that absorb water into the colon, thus softening stools. Its primary use is to treat constipation. It is also used to reduce blood ammonia levels in persons with liver disease since lactulose absorbs ammonia into the colon (removing it from the body). Trehalose glucose + glucoseTrehalose is also known as tremalose or mycose. It is a natural alpha-linked disaccharide with extremely high water retention properties. In nature, it helps plants and animals reduce long periods without water. Cellobiose glucose + glucoseCellobiose is a hydrolysis product of cellulose or cellulose-rich materials, such as paper or cotton. It is formed by linking two beta-glucose molecules by a β(1→4) bond. Table of Common Disaccharides Here's a quick summary of the subunits of common disaccharides and how they are linked to each other. Dissacharide First Unit Second Unit Bond sucrose glucose fructose α(1→2)β lactulose galactose fructose β(1→4) lactose galactose glucose β(1→4) maltose glucose glucose α(1→4) trehalose glucose glucose α(1→1)α cellobiose glucose glucose β(1→4) chitobiose glucosamine glucosamine β(1→4) There are many other disaccharides, although they are not as common, including isomaltose (2 glucose monomers), turanose (a glucose and a fructose monomer), melibiose (a galactose and a glucose monomer), xylobiose (two xylopyranose monomers), sophorose (2 glucose monomers), and mannobiose (2 mannose monomers). Bonds and Properties Note multiple disaccharides are possible when monosaccharides bond to each other, since a glycosidic bond can form between any hydroxyl group on the component sugars. For example, two glucose molecules can join to form maltose, trehalose, or cellobiose. Even though these disaccharides are made from the same component sugars, they are distinct molecules with different chemical and physical properties from each other. Uses of Disaccharides Disaccharides are used as energy carriers and to efficiently transport monosaccharides. Specific examples of uses include: In the human body and in other animals, sucrose is digested and broken into its component simple sugars for quick energy. Excess sucrose can be converted from a carbohydrate into a lipid for storage as fat. Sucrose has a sweet flavor.Lactose (milk sugar) is found in human breast milk, where it serves as a chemical energy source for infants. Lactose, like sucrose, has a sweet flavor. As humans age, lactose becomes less-tolerated. This is because lactose digestion requires the enyzme lactase. People who are lactose intolerant can take a lactase supplement to reduce bloating, cramping, nausea, and diarrhea.Plants use disaccharides to transport fructose, glucose, and galactose from one cell to another.Maltose, unlike some other disaccharides, does not serve a specific purpose in the human body. The sugar alcohol form of maltose is maltitol, which is used in sugar-free foods. Of course, maltose is a sugar, but it is incompletely digested and absorbed by the body (50–60%). Key Points A disaccharide is a sugar (a type of carbohydrate) made by linking together two monosaccharides.A dehydration reaction forms a disaccharide. One molecule of water is removed for each linkage formed between the monosaccharide subunits.Both natural and artificial disaccharides are known.Examples of common disaccharides include sucrose, maltose, and lactose. Additional References IUPAC, "Disaccharides." Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997).Whitney, Ellie; Sharon Rady Rolfes (2011). Peggy Williams, ed. Understanding Nutrition (Twelfth ed.). California: Wadsworth, Cengage Learning. p. 100. View Article Sources Treepongkaruna, S., et al. "A randomised, double-blind study of polyethylene glycol 4000 and lactulose in the treatment of constipation in children." BMC Pediatrics, vol. 14, no. 153, 19 June 2014. doi:10.1186/1471-2431-14-153 Jover-Cobos, Maria, Varun Khetan, and Rajiv Jalan. "Treatment of hyperammonemia in liver failure." Current Opinion in Clinical Nutrition and Metabolic Care, vol. 17, no. 1, 2014, pp. 105–110 doi:10.1097/MCO.0000000000000012 Pakdaman, M.N. et al. "The effects of the DDS-1 strain of lactobacillus on symptomatic relief for lactose intolerance - a randomized, double-blind, placebo-controlled, crossover clinical trial." Nutrition Journal, vol. 15, no. 56, 2015, doi:10.1186/s12937-016-0172-y Polysaccharide Definition and Functions Monosaccharide Definition and Functions What Is the Molecular Formula for Sugar (Sucrose)? Know the Chemical or Molecular Formula for Glucose Get to Know the Biology of Carbohydrates Learn About the Kinds of Organic Compounds Know the Chemical Formula of Sugar What Is Cellulose? Facts and Functions 10 Examples of Carbohydrates How Lactose Free Milk Is Made Biology Prefixes and Suffixes: glyco-, gluco- What are Monomers and Polymers and How Do They Fit Together? What Is a Glycosidic Bond? Disaccharide Definition What is the science behind carbohydrates? What Are Biological Polymers?