Aspergillus niger

Aspergillus niger is a fungus and one of the most common species of the genus Aspergillus. It causes a disease called "black mold" on certain fruits and vegetables such as grapes, onions, and peanuts, and is a common contaminant of food. It is ubiquitous in soil and is commonly reported from indoor environments, where its black colonies can be confused with those of Stachybotrys (species of which have also been called "black mold").

Characteristics

Aspergillus niger is a haploid fungus and grows by elongation of the hyphae and forms a mycelium. It is differentiated from other aspergilli by its black conidial heads. The conidia, which are the asexual spores of the fungus, are formed in long chains from the tips of the phialides, with the youngest spore at the base of the chain, and the oldest and first formed spore at the tip of the chain.

Pathogenicity

While Aspergillus niger is less likely to cause human disease than some other Aspergillus species, it has been known to infect the lungs of immunocompromised individuals, and is a common cause of otomycosis (fungal ear infections). In rare instances, it can cause aspergillosis in the lungs of individuals with a weakened immune system.

Industrial uses

Aspergillus niger is one of the most important industrial microorganisms. It has been in use for over a century and its industrial exploitation has been important to the development of biotechnology. It is used in the production of citric acid, gluconic acid, and many enzymes. It is also used in waste management and biotransformations.

See also

• Aspergillus
• Aspergillosis
• Mycology