C12H22O11 + H2O - C6H12O6 + C6H12O6 (Sucrose - Glucose + Fructose)
C6H12O6 - 2C2H5OH + 2CO2 (Gluc

Q: Why is the hydrolysis of sucrose called 'inversion'?

Sucrose itself is dextrorotatory (rotates plane-polarized light to the right). However, upon hydrolysis, it forms glucose (dextrorotatory) and fructose (strongly levorotatory). The net rotation of the resulting mixture is levorotatory. This change in the sign of optical rotation is called inversion, and the mixture is called invert sugar.

Q: What exactly is Zymase?

Zymase is not just a single enzyme, but an enzyme complex that catalyzes the fermentation of sugar into ethanol and carbon dioxide. It occurs naturally in yeasts and is crucial for the brewing and baking industries.

Q: What does the enzyme Amylase do?

Amylase is an enzyme that catalyzes the hydrolysis of starch (a polysaccharide) into smaller carbohydrate molecules like maltose. It is found in human saliva and plays a key role in digestion.

Q: Can Invertase break down other disaccharides like maltose?

No, enzymes are highly specific to their substrates. Invertase specifically targets the glycosidic bond in sucrose. To break down maltose, a different enzyme called Maltase is required.

Q: Are these enzymatic reactions exothermic or endothermic?

The fermentation of glucose (the second reaction) is an exothermic process, meaning it releases heat along with the production of ethanol and carbon dioxide.

Question

$C_{12}H_{22}O_{11} + H_2O \xrightarrow{	ext{Enzyme A}} C_6H_{12}O_6 + C_6H_{12}O_6$
(Sucrose) \quad\quad\quad\quad\quad\quad\quad\quad (Glucose) \quad (Fructose)

$C_6H_{12}O_6 \xrightarrow{	ext{Enzyme B}} 2C_2H_5OH + 2CO_2$
(Glucose) \quad\quad\quad\quad\quad\quad (Ethanol)

In the above reactions, the enzyme A and enzyme B respectively are

Options:

(A) amylase and invertase

(B) invertase and amylase

(C) invertase and zymase

(D) zymase and invertase

Sigma Percentile · Accepted Answer

### The Magic of Enzymes: From Sugar to Alcohol

Enzymes are nature's highly specific biological catalysts. They are remarkable proteins that accelerate complex biochemical reactions with incredible precision. In this problem, we explore two classic enzymatic reactions that have been utilized by humanity for centuries: the inversion of sugar and the fermentation of glucose.

### Analyzing the First Reaction: Hydrolysis of Sucrose

The first reaction presented is the hydrolysis of sucrose:

$$C_{12}H_{22}O_{11} + H_2O \xrightarrow{	ext{Enzyme A}} C_6H_{12}O_6 + C_6H_{12}O_6$$

Here, sucrose (common table sugar) reacts with water to break its glycosidic bond, yielding an equimolar mixture of D-glucose and D-fructose. This specific mixture is often called "invert sugar" because the optical rotation of the solution changes from dextrorotatory (due to sucrose) to levorotatory (dominated by the strongly levorotatory fructose) as the reaction proceeds.

The enzyme responsible for this precise cleavage is **Invertase**. It specifically targets the $\beta$-fructofuranosidase linkage in sucrose.

### Analyzing the Second Reaction: Fermentation of Glucose

The second reaction takes the glucose produced and ferments it:

$$C_6H_{12}O_6 \xrightarrow{	ext{Enzyme B}} 2C_2H_5OH + 2CO_2$$

In this anaerobic process, glucose is broken down into ethanol and carbon dioxide. This is the fundamental chemical reaction behind brewing and baking. The catalyst for this transformation is not a single enzyme, but rather a complex of enzymes known collectively as **Zymase**. Zymase is naturally produced by yeast cells and is responsible for the entire glycolytic pathway leading to ethanol.

### Final Conclusion

By matching the biochemical processes to their specific biological catalysts, we can confidently identify the enzymes. Enzyme A, which hydrolyzes sucrose, is **Invertase**. Enzyme B, which ferments glucose into ethanol, is **Zymase**. This perfectly aligns with the given options, leading us to the correct answer.

Select Answer:

Visualized Solution

$Hydrolysis of Sucrose$

$Fermentation of Glucose$

$Conclusion$

The Sigma Insight: Biomolecules

The Magic of Enzymes

Analyzing the First Reaction

Analyzing the Second Reaction

Final Conclusion

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