The name of this mycotoxin comes from Penicillium citrinum, the organism from which it was firstly isolated in 1931.3 Citrinin is produced by several strains of Penicillium and Aspergillus, this is the reason why it often occurs with Ochratoxin A.3, 4 Other citrinin producing Penicillium spp. are P. lividum, P. implicatum, P. citreoviride, P. viridicatum and others.3, 7 Some Monascus strains are known to produce citrinin as well.5 Chemically, citrinin is a phenolic derivate compound and presents a bright yellow color on chromatograms viewed under visible light.4 This mycotoxin is insoluble in water and it dissolves in ethanol, benzene, acetone and chloroform.1, 6
Production and occurrence
Citrinin has been isolated from its natural occurrence in cereal grains such as wheat, barley, oats, rice and corn. Probably the major characteristic of its occurrence is that it often co-occurs with ochratoxin A in the cereals and most isolates of fungi that produce citrinin also produce ochratoxin A. The conditions under which citrinin occurs in the field are presumed to be similar to that for ochratoxin and levels have been found in cereal grains as high as 80 ppm. Unfortunately, little is known regarding the field occurrence of either ochratoxin or citrinin and therefore they are considered as storage problems in grains, although ochratoxin is known to occur in certain crops at harvest such as grapes but this is usually the result of production by some of the “black” aspergilli such as A. carbonarius.
Effects / Toxicity
Originally, citrinin was characterized as an antibacterial antibiotic.3, 4 It is able to inhibit growth of several bacterial species (mainly Gram-positive e.g. Bacillus subtilis and several Micrococcus strains). Further, protozoa, filamentous fungi and yeasts are also known to be affected.1,5,6 However, toxicity studies in animals showed that the compound was too toxic for use as an anitibiotic.
Toxic effects were extensively studied on model animals like mice, swine and poultry, with the kidney identified as main target organ.1, 3, 4, 6, 7 These effects include enlargement and degeneration of proximal tubules.5 In addition, citrinin exerts a depressive action on the central nervous system.1, 3, 5 Dietary exposure to citrinin has been reported to impair liver metabolism, increase water consumption, provoke diarrhea and alter intestinal villar morphology (the last is a poultry specific problem).1, 3, 4, 6, 7 Furthermore, citrinin has teratogenic and carcinogenic proprieties.3, 5
In the EU, there is a regulation about the maximum allowed level of citrinin in food supplements are based on rice fermented with red yeast Monascus purpureusThis limit is set to 2000 ppb.2 No regulation exists for the presence of this mycotoxin in feed. In the US, no regulation exists for food and for feed.
- Betina V. (1989) Mycotoxins Chemical, Biological and Environmental Aspects. Bioactive Molecules (9) 174-191.
- COMMISSION REGULATION (EU) No 212/2014 of 6 March 2014 amending Regulation (EC) No 1881/2006 as regards maximum levels of the contaminant citrinin in food supplements based on rice fermented with red yeast Monascus purpureus.
- Keblys M., Bernhoft A., Höfer C.C., Morrison E., Jørgen H., Larsen S., Flåøyen A. (2004). The effects of the Penicillium mycotoxins citrinin, cyclopiazonic acid, ochratoxin A, patulin, penicillic acid, and roquefortine C on in vitro proliferation of porcine lymphocytes. Mycopathologia (158) 317–324.
- Krska R., Nährer K., Richard J. L., Rodrigues I., Schuhmacher R., Slate A. B., Whitaker T. B., (2012). Guide to Mycotoxins featuring Mycotoxin Risk Management in Animal Production. BIOMIN edition 2012.
- Marin S., Ramos A.J., Cano-Sancho G., Sanchis V., (2013). Mycotoxins: Occurrence, toxicology, and exposure assessment. Food and Chemical Toxicology (60) 218-237.
- Richard J.L., (2007). Some major mycotoxins and their mycotoxicoses - an overview. International Journal of Food Microbiology (119) 3-10.
- Vankudoth Koteswara Rao, Sivadevuni Girisham & Solipuram Madhusudhan Reddy (2016): Prevalence of Toxigenic Penicillium species Associated with Poultry House in Telangana, India. Archives of Environmental & Occupational Health.