Ochratoxin producers, detection

Bogs, C., Battilani, P., and Geisen, R. (2006). Development of a molecular detection and differentiation system for ochratoxin A producing Penicillium species and its application to analyse the occurrence of Penicillium nordicum in cured meat. Int. J. Food Microbiol. 107, 39 7. 

Another important and widespread fungal toxin is ochratoxin, which is also found in cereals and, to a lesser extent, in coffee and cocoa beans. The toxin Ochratoxin A is the most commonly found and is produced by the Aspergillus t5rpe of fungus. Exposure occurs in many countries in Europe and affects farm animals as well as humans. The major toxic effect in both humans and animals is kidney damage and cancer of the kidney. The available epidemiological evidence indicates that the disease called Balkan nephropathy is associated with consumption of food contaminated with ochratoxin, and the toxin has been detected in the blood of people living... 

Ochratoxin-A (OTA), a mycotoxin produced in unstored food and beverages has recently been detected using CH-Fe304 nanobiocomposite modified indium-tin oxide (ITO) electrode [73], This immunosensor shows a specific response to OTA detection in the range of 0.5 - 6 ng/dL with a detection limit of 0.5 ng dL 1. The sensitivity of the bioelectrode has been found to be 36 pA/ng dL"1 cm 2 with response time of 18s [101],... 

Ochratoxin A formation in apricot jam has been investigated by Ruhland et al. (1998). Apricot jam prepared conventionally was inoculated with ochratoxin A-producing A. ochraceus and P. verrucosum. Fungal growth was detected after two weeks and mycotoxin production after five weeks. Ochratoxin A contents reached up to 86.3 pg/kg for A. ochraceus and 94.6 pg/kg for P. verrMcosum-inoculated jams. Seven of twelve naturally contaminated jam samples contained 0.09-14.33 pg/kg ochratoxin A. In a market survey, Engel (2000) could not detect ochratoxin A at a concentration higher than 0.1 pg/kg in 42 commercial jam samples. 

Numerous studies have detected A. ochraceus (and related species) in green coffee beans (e.g. Levi et al., 1974 Cantaforaetal., 1983 Studer-Rohret al., 1994 Taniwaki et al., 2003). Although these species are one source of ochratoxin A in coffee (Taniwaki et al., 1999), studies indicate that A. carbonarius is a more important source in coffee from most producing countries. 

The analysis of mycotoxins, toxic substances produced by some fungi, is essential to guaranteeing the safety of foods such as cereals, nuts, oilseeds, and spices since the discovery of their significance to human health. The main mycotoxins, like aflatoxins and ochratoxin A, are determined using HPLC with octyl-or octadecyl-bonded phases and polar solvents such as methanol, acetonitrile, and water. For detection with the required sensitivity and selectivity, spectrofluori-metric detection is the most common method, with increasing use of mass spectrometric interfaces. 

Hayat, A., Paniel, N., Rhouati, A. et al. (2012) Recent advances in ochratoxin A-producing fungi detection based on PCR methods and ochratoxin A analysis in food matrices. Food Control, 26,401-415. 

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