S. C. Pei (1), Y. P. Zhen (1), J. W. Gao (1), Y. Li (1), W. J. LEE (2);
(1) Qiqihar University, Qiqihar, China; (2) Gangneung Wonju National University, Gangneung, Korea
Citrinin (CIT) is a fungal metabolite and a common food contaminant which can cause the deterioration of liver or kidney function in animals. Corn and rice used in the brewing process have frequently been reported to be contaminated with fungi. In some countries, beer samples have been reported to be contaminated with a high concentration of CIT during the summer season. In this study, CIT protein conjugate antigen was prepared with bovine serum albumin (BSA), ovalbumin (OVA), and keyhole limpet hemocyanin (KLH) using CIT-BSA, CIT-KLH, CIT-OVA, CIT-DCC-BSA, and CIT-DCC-OVA. Titration results showed that only anti-CIT-KLH serum highly combined to CIT-BSA conjugate and CIT. The linear range for the developed indirect competitive ELISA was 1–100 µg/kg of CIT concentration, and the limit of detection for CIT was 0.1 µg/kg. Half maximal (50%) inhibitory concentration (IC50) of the anti-CIT-KLH serum was 9.8 µg/kg. The recovery rate of CIT from spiked grain samples was between 81.6% and 132%. The cross-reactivities of the anti-CIT-KLH serum against salbutamol, ractopamine, patulin, and aflatoxin B1 were less than 1.0%. A total of 88 samples of corn and rice were collected from farms and supermarkets in northeastern China. Among the samples tested by IC-ELISA, CIT was not detected in 85 (96.6%) of the samples. Only 1 corn and 2 rice samples were positive for CIT. The risk of CIT in corn and rice from northeastern China seems to exist as a public health concern and CIT concentration should be continuously monitored.
Won Jong Lee is a professor in the Department of Food and Nutrition at Gangneung Wonju National University, Korea. He received his Ph.D. degree in cereal science from North Dakota State University.