What is the Difference Between Cellobiose and Maltose

The main difference between cellobiose and maltose is that cellobiose connects through the b-position of the C1 carbon, whereas maltose connects through the a-position of the C1 carbon.

Cellobiose and maltose are two types of dimers of D-glucose. Generally, both form condensing monomers at their C1 and C4 positions removing H20. In addition, they are reducing sugars.                                                                       

Key Areas Covered

1. What is Cellobiose
     – Definition, Structure, Function
2. What is Maltose
     – Definition, Structure, Function
3. Similarities – Cellobiose and Maltose
     – Outline of Common Features
4. Difference Between Cellobiose and Maltose
     – Comparison of Key Differences

Key Terms                                                                                                                  

Cellobiose, Maltose

What is Cellobiose

Cellobiose is a disaccharide that is a reducing sugar. The formation of cellobiose occurs through the β (1→4) bond. However, the formation of cellobiose occurs from the partial digestion of cellulose. Generally, this can be enzymatic or acidic hydrolysis of cellulose. Paper, jute, and cotton are materials rich in cellulose. In addition, cellobiose hydrolyses into glucose with acids or through enzymes. Cellobiose also contains eight free alcohol groups. They contain one acetal linkage and one hemiacetal linkage. More importantly, they give rise to strong hydrogen bonds that are intramolecular and intermolecular.

Figure 1: Cellobiose

Furthermore, cellobiose serves as an indicator carbohydrate for diseases like malabsorption syndrome and Crohn’s disease. The chemical formula of cellobiose is C₁₂H₂₂O₁₁, while its molecular mass is 342.297 g·mol−1. The appearance of cellobiose is white, hard powder. In addition to that, it is odorless. Normally, the density of cellobiose is 1.768 g/mL. Generally, cellobiose is very slightly soluble in alcohol.  

What is Maltose

Maltose is a sugar that contains two glucose units, containing α (1→4) bonds between them. It serves as a member of amylose, the key structural motif of starch. Therefore, the beta-amylase breakdown of starch produces maltose. In general, beta-amylase removes two glucose units at a time. The breakdown of starch also occurs in germinating seeds. Maltose is a reducing disaccharide. Hence, it opens to presenting a free aldehyde group. Maltase is also the enzyme responsible for the breakdown of maltose, catalyzing the hydrolysis of the glycosidic bond.

Figure 2: Moltose

Moreover, maltose exhibits mutarotation, forming α and β isomers in aqueous solutions. Generally, different conformations of the anomeric carbon are responsible for different specific rotations in aqueous solutions.  Germinating grains contain maltose. In addition, maltose occurs in different quantities in partly hydrolyzed products of starch, including maltodextrin, acid-thinned starch, and corn syrup.

Similarities Between Cellobiose and Maltose

• Cellobiose and maltose are two types of dimers of D-glucose.
• Both are reducing sugars.
• They have a similar chemical formula, C₁₂H₂₂O₁₁.
• Both undergo condensation at their C1 and C4 positions removing H20.

Difference Between Cellobiose and Maltose

Definition

Cellobiose refers to a white crystalline water-soluble disaccharide, while maltose refers to a sugar produced by the breakdown of starch, e.g. by enzymes found in malt and saliva.

Occurrence

Moreover, cellobiose occurs from the partial digestion of cellulose, while maltose occurs from the partial digestion of starch.

Condensation

Cellobiose connects through the b-position of the C1 carbon, while maltose connects through the a-position of the C1 carbon.

Bond Formation

Cellobiose forms β(1→4) bond while maltose forms α(1→4) bond.

Conclusion                                                      

In brief, cellobiose and maltose are two types of disaccharides that are reducing sugars. Both undergo condensation at their C1 and C4 positions. Generally, cellobiose occurs from the partial digestion of cellulose. Cellobiose forms β (1→4) bond, connecting through b-position of the C1 carbon. In comparison, maltose occurs from the partial digestion of starch. In addition, it forms α (1→4) bond between C1 and C4 carbons. Therefore, the main difference between cellobiose and maltose is their structure and formation.                                  

References:                

1. Cellobiose. Biology Articles, Tutorials & Dictionary Online. 
2. Maltose – structure, formula, properties, production, uses. BYJUS. 

Image Courtesy:

1. “Cellobiose skeletal” By Alhadis – Own work (Public Domain) via Commons Wikimedia
2. “Maltose2” By NEUROtiker – Own Work (Public Domain) via Commons Wikimedia