Question

In alcoholic fermentation, NAD+ is produced during the
A. Reduction of acetaldehyde to ethanol
B. Oxidation of glucose
C. Oxidation of pyruvate to acetyl CoA
D. Hydrolysis of ATP to ADP

Answer 1

Hint: Alcoholic fermentation is also known as ethanol fermentation. The main product obtained after the process of fermentation is in the form of cellular energy. The by-product obtained along with the main product after the process of alcoholic fermentation is alcohol and carbon dioxide.

Complete answer: The process of alcoholic fermentation produces two molecules of ethanol and two molecules of carbon dioxide from one molecule of glucose. The overall chemical reaction for the process of alcoholic fermentation can be written as: \[{{C}_{12}}{{H}_{22}}{{O}_{11}}~+\text{ }{{H}_{2}}O\text{ }+\text{ }invertase\text{ }\to \text{ }2\text{ }{{C}_{6}}{{H}_{12}}{{O}_{6}}\]. The first step of alcoholic fermentation is the conversion of sucrose into glucose, which is done by using the enzyme invertase that cleaves the glycosidic bond between the glucose and fructose as the sucrose is made up of one unit of glucose and one unit of fructose. Further, the glucose molecule is converted into pyruvate in the process of glycolysis. The metabolic process of conversion of glucose into pyruvate is called glycolysis which takes place in the cytoplasm of the cell. During the process of glycolysis, NAD+ is formed during the reduction of acetaldehyde to ethanol.
Therefore, option A is the correct answer.

Note: One of the methods of alcohol production is by molasses fermentation. Formation of alcohol with the use of molasses is one of the most cost-effective ways of production of alcohol. The appropriate substrate is provided by Molasses from sugarcane or sugar in the production of ethanol. The sucrose ${{C}_{12}}{{H}_{22}}{{O}_{11}}$ present in the molasses is the basic source of concentrated sugar.