Citrinin is a mycotoxin

Mycotoxin

A mycotoxin is a toxic secondary metabolite produced by organisms of the fungus kingdom, commonly known as molds. The term ‘mycotoxin’ is usually reserved for the toxic chemical products produced by fungi that readily colonize crops...

 originally isolated from Penicillium citrinum. It has since been found to be produced by a variety of other fungi which are used in the production of human foods such as grain, cheese, sake and red pigments. Citrinin has also been found in commercial red yeast rice supplements.

Toxicity

Citrinin acts as a nephrotoxin in all species in which it has been tested, but its acute toxicity varies. It causes mycotoxic nephropathy in livestock and has been implicated as a cause of Balkan nephropathy

Balkan nephropathy

Danubian endemic familial nephropathy , also called Balkan endemic nephropathy, is a form of interstitial nephritis. It was first identified in the 1920s among several small, discrete communities along the Danube River and its major tributaries, in the modern countries of Croatia, Bosnia and...

 and yellow rice fever in humans.

Citrinin is used as a reagent

Reagent

A reagent is a "substance or compound that is added to a system in order to bring about a chemical reaction, or added to see if a reaction occurs." Although the terms reactant and reagent are often used interchangeably, a reactant is less specifically a "substance that is consumed in the course of...

 in biological research. It induces mitochondrial permeability pore opening and inhibits respiration

Cellular respiration

Cellular respiration is the set of the metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate , and then release waste products. The reactions involved in respiration are catabolic reactions that involve...

 by interfering with complex I of the respiratory chain.

Citrinin producers

Citrinin is produced by a variety of fungi including:

• Aspergillus niveus
• Aspergillus ochraceus
• Aspergillus oryzae
  Aspergillus oryzae
  Aspergillus oryzae is a filamentous fungus . It is used in Chinese and Japanese cuisine to ferment soybeans. It is also used to saccharify rice, other grains, and potatoes in the making of alcoholic beverages such as huangjiu, sake, and shōchū...
  
  
• Aspergillus terreus
  Aspergillus terreus
  Aspergillus terreus is a fungus commonly used in industry to produce important organic acids, such as itaconic acid and cis-aconitic acid. It was also the initial source for the drug mevinolin , a drug for lowering serum cholesterol. A. terreus may cause opportunistic infection in people with...
  
  
• Monascus ruber
• Monascus purpureus
  Monascus purpureus
  Monascus purpureus is a species of mold that is purplish-red in color...
  
  
• Penicillium citrinum
• Penicillium camemberti
  Penicillium camemberti
  Penicillium camemberti is a species of fungus used in the production of Camembert and Brie cheeses, on which colonies of P. camemberti form a hard, white crust. It is responsible for giving these cheeses their distinctive taste.- Synonyms :...