A quantitative UHPLC-MS/MS method for citrinin and ochratoxin A detection in food, feed and red yeast rice food supplements

Abstract

Mycotoxins may cause deleterious effects (among others nephrogenic, hepatogenic, carcinogenic, teratogenic, neurogenic) in animals and humans, therefore they have been intensely studied and monitored over the years. For citrinin (CIT), a nephrotoxic mycotoxin, however, this has not yet been the case. According to the latest European Food Safety Authority report, a correct risk assessment of CIT was not possible due to the lack of occurrence data. Besides, traces of CIT or its metabolite, dehydrocitrinone are widely (in up to 90% of samples) present in human urine according to recent Belgian and German scientific reports, which might imply chronic exposure. Only recently, a European maximum limit has been set for CIT in cholesterol reducing food supplements including red yeast fermented rice (RYR). During production of RYR through fungal (among others Monascus purpureus) fermentation of rice other components, like CIT, as well as nephrotoxic ochratoxin A (OTA) may form. Consequently, the present work attempted develop to a robust and routinely applicable ultra-high performance liquid chromatographytandem mass spectrometry (UHPLC-MS/MS) method for the analysis of CIT and OTA in food, feed and in RYR food supplements. The method was successfully validated based on EU/657/2002 and EU/519/2014 in RYR food supplements and wheat flour, achieving respective limits of quantification (LOQ) for CIT of 0.4 μg/kg and 0.1 μg/kg and for OTA of 15 μg/kg and 0.4 μg/kg. The average between-day recoveries varied from 72 to 110% with relative standard deviations ≤16%. Single-day validation in rice, curry and apple matrices showed LOQs ranging from 0.3-1.0 μg/kg. Next, the occurrence of CIT/OTA was surveyed in 138 RYR, food and feed samples, proving the potential of this method for future data acquisition within a risk assessment framework specifically for CIT, while also gaining information about the (co-)occurrence of OTA in edible matrices.

Validation of an LC-MS/MS-based dilute-and-shoot approach for the quantification of > 500 mycotoxins and other secondary metabolites in food crops: challenges and solutions

“…Another minor change is related to citrinin that has been transferred to the negative ESI mode, as the related MRM transitions deriving from the deprotonated methanol adduct [M+CH 3 OH-H] − exhibited a drastically increased signal compared with the positive mode [22].…”

Pre‐ and Postharvest Strategies to Minimize Mycotoxin Contamination in the Rice Food Chain

“…Mainly for its health benefits by lowering cholesterol levels, there is an increasing interest for RYR around the world (Kalaivani, Sabitha, Kalaiselvan, & Rajasekaran, 2010). In RYR, the levels of monacolin K, which is formed during the fermentation process and inhibits HMG-CoA reductase (involved in cholesterol synthesis), are crucial to achieve the desirable functional properties, but since fungal activity is also associated with the production of CIT, there is a demand for the optimization of the process (Kalaivani et al, 2010;Kiebooms, Huybrechts, Thiry, Tangni, & Callebaut, 2016;Liao, Chen, Lin, Chiueh, & Shih, 2014). The selection of Monascus strains and the application of mutagenesis techniques to increase the monacolin K/CIT ratio produced during fermentation are being explored (Kanpiengjai, Mahanwan, Pengnoi, Lumyong, & Khanongnuch, 2018;Tsukahara, Shinzato, Tamaki, Namihira, & Matsui, 2009).…”

Red Yeast Rice: A Systematic Review of the Traditional Uses, Chemistry, Pharmacology, and Quality Control of an Important Chinese Folk Medicine

“…Citrinin is a polyketide secondary metabolite found in food and feed that is produced by several fungi, including M. purpureus (Bezeria da Rocha et al, 2014; Kiebooms et al, 2016). It is a mycotoxin known to cause kidney damage as well as disrupt metabolic processes in the liver (Mornar et al, 2013).…”

“…The EFSA has set a level of no concern for citrinin-caused nephrotoxicity at 0.2 µg/kg body weight per day, but it has acknowledged the need for more reliable data on the citrinin level in food and feed before it can undertake exposure studies and risk assessment (Marley et al, 2016). Different analytical methods have been developed for the quantification of citrinin in a variety of samples in the last few years, including LC-FDA (Marley et al, 2016), UHPLC-MS/MS (Kiebooms et al, 2016), UHPLC–DAD–QToF-MS (Avula et al, 2014), LC-DAD/FLD-MS n (Mornar et al, 2013), microsphere-based flow cytometric immunoassays (MFCI) (Li et al, 2012), and a multi-commutated fluorometric optosensor technology (Jimenez Lopez et al, 2014). The maximum allowed level of citrinin as a contaminant in RYR is 200 ppb in Japan, but the European Union has recommended a limit of 100 ppb (Mornar et al, 2013; Nigovic et al, 2013).…”