Question

Which one of the following microorganism is used for production of citric acid in industries?

• A. Lactobacillus bulgaricus
• B. Penicillium citrinum
• C. Aspergillus niger
• D. Rhizopus nigricans

Answer 1

The correct option is C Aspergillus niger

The citric acid (2-hydroxy-propane-1,2,3-tricarboxylic acid) is a tricarboxylic acid which contains three carboxylic functional groups. It is a primary metabolic product formed in the tricarboxylic acid (or Krebs) cycle. Citric acid is the most important organic acid produced in tonnage and is extensively used in food and pharmaceutical industries. It is produced mainly by submerged fermentation using Aspergillus niger or Candida sp. from different sources of carbohydrates, such as molasses and starch-based media.

So, the correct answer is option C.