The artificial sweetener, aspartame, is enzymatically produced using
1. 𝛽-galactosidase
2. rennin
3. lipase
4. Thermolysin

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Detailed Explanation:

The correct answer is: 4. Thermolysin

What is Aspartame?

Aspartame is a low-calorie artificial sweetener that is approximately 200 times sweeter than sucrose (table sugar). It is widely used in sugar-free and diet products, including soft drinks, chewing gums, and sugar substitutes. Chemically, aspartame is a dipeptide methyl ester composed of two amino acids: L-aspartic acid and L-phenylalanine methyl ester.

Enzymatic Production of Aspartame:

The industrial production of aspartame involves the enzymatic condensation of the two amino acids. The enzyme used in this biocatalytic process is thermolysin.

• Thermolysin is a heat-stable protease obtained from Bacillus thermoproteolyticus.

• It catalyzes the formation of a peptide bond between the carboxyl group of L-aspartic acid and the amino group of L-phenylalanine methyl ester.

• The reaction is highly specific, efficient, and avoids racemization (formation of D-isomers), ensuring the sweetener retains its safe and functional structure.

Why Not Other Enzymes?

• β-Galactosidase is involved in the hydrolysis of lactose and is not used in dipeptide synthesis.

• Rennin (chymosin) is used in the coagulation of milk proteins in cheese-making.

• Lipase catalyzes the breakdown of fats and is unrelated to peptide bond formation.

Importance in the Food Industry:

Using enzymatic synthesis with thermolysin offers several advantages:

• High specificity leading to minimal byproducts

• Cost-effective and environmentally friendly production

• Scalability for industrial use in food manufacturing

Conclusion:

Aspartame, a widely used artificial sweetener, is enzymatically synthesized using thermolysin, a specific protease that links aspartic acid and phenylalanine methyl ester. This method ensures high purity, safety, and efficiency in large-scale production.