Write the most important characteristic that Aspergillus niger, Clostridium butylicum, and Lactobacillus share.

The most important characteristic that Aspergillus niger, Clostridium butylicum, and Lactobacillus shareare that they all are micro-organisms which are involved in the production of various acids. i.e., Aspergillus niger is used for the production of citric acid, Clostridium butylicum is used for the production of butyric acid and Lactobacillus is used for the production of lactic acid.