Simultaneous enzyme immunoassay for the screening of aflatoxin B1 and ochratoxin A in chili samples.

Membrane-based immunoassay has been developed for simultaneous estimation of aflatoxin B(1) (AFB(1)) and ochratoxin A (OA) in chili samples. The combined estimation of both the mycotoxins is more economical in respect of time, work and materials than two separate assays. The method uses a low cost test device consisting of a membrane with immobilized anti-AFB(1) and anti-OA antibodies and a filter paper attached to a polyethylene card below the membrane. It allows direct analysis of sample extracts containing substantial amount (40%) of methanol. This permits the use of two-fold diluted sample extracts resulting in minimum dilution error. The limit of quantitation obtained was 2 and 10 microg kg(-1) for AFB(1) and OA, respectively. The tolerance of 40% methanol was found to be due to the application of small size (0.8 mm diameter) spots on membranes, as the tolerance decreases to 20% with gradual increase in spot size. The combined method is capable of producing acceptable results to analyze AFB(1) and OA in chili with accuracy and precision. The AFB(1) and OA values obtained for spiked and naturally contaminated chili samples by the simultaneous method were in good correlation with those measured by individual ELISA. The method offers a simple, rapid and cost-effective screening tool to meet the requirements of the rapidly evolving EU legislation.

[1]  H. M. Martins,et al.  Aflatoxins in spices marketed in Portugal , 2001, Food additives and contaminants.

[2]  T. Dhar,et al.  Antibody to folic acid: increased specificity and sensitivity in ELISA by using epsilon-aminocaproic acid modified BSA as the carrier protein. , 1995, Journal of immunological methods.

[3]  Ewald Usleber,et al.  Rapid Detection of Fumonisin B1 in Corn-Based Food by Competitive Direct Dipstick Enzyme Immunoassay/Enzyme-Linked Immunofiltration Assay with Integrated Negative Control Reaction , 1995 .

[4]  Angel Maquieira,et al.  On-line immunoanalysis for environmental pollutants: from batch assays to automated sensors , 1999 .

[5]  Miriam M. Ngundi,et al.  Array biosensor for detection of ochratoxin A in cereals and beverages. , 2005, Analytical chemistry.

[6]  R. García-Villanova,et al.  Simultaneous immunoaffinity column cleanup and HPLC analysis of aflatoxins and ochratoxin A in Spanish bee pollen. , 2004, Journal of agricultural and food chemistry.

[7]  D. Reddy,et al.  Aflatoxins B1 in different grades of chillies (Capsicum annum L.) in India as determined by indirect competitive-ELISA , 2001, Food additives and contaminants.

[8]  A. Sharma,et al.  Teratogenic effects in rabbits of simultaneous exposure to ochratoxin A and aflatoxin B1 with special reference to microscopic effects. , 2005, Toxicology.

[9]  Debopam Acharya,et al.  In situ sample cleanup during immunoassay: a simple method for rapid detection of aflatoxin B, in food samples. , 2005, Journal of food protection.

[10]  G. Speijers,et al.  Combined toxic effects of mycotoxins. , 2004, Toxicology letters.

[11]  M. Váradi,et al.  Development of immunosensor based on OWLS technique for determining Aflatoxin B1 and Ochratoxin A. , 2007, Biosensors & bioelectronics.

[12]  Jonathan W. DeVries,et al.  Mycotoxins and Food Safety , 2002, Advances in Experimental Medicine and Biology.

[13]  B. Fazekas,et al.  Aflatoxin and ochratoxin A content of spices in Hungary , 2005, Food additives and contaminants.

[14]  D. Bhattacharya,et al.  A novel signal amplification technology for ELISA based on catalyzed reporter deposition. Demonstration of its applicability for measuring aflatoxin B(1). , 1999, Journal of immunological methods.

[15]  G. Reddy,et al.  Production of polyclonal antibodies against ochratoxin A and its detection in chilies by ELISA. , 2000, Journal of agricultural and food chemistry.

[16]  Debjani Saha,et al.  Development of a membrane-based immunofiltration assay for the detection of T-2 toxin. , 2004, Analytical chemistry.

[17]  Ewald Usleber,et al.  Rapid methods for deoxynivalenol and other trichothecenes. , 2004, Toxicology letters.

[18]  D. Shon,et al.  Natural co-occurrence of aflatoxin B1, fumonisin B1 and ochratoxin A in barley and corn foods from Korea , 2002, Food additives and contaminants.

[19]  Miriam M. Ngundi,et al.  Rapid detection of foodborne contaminants using an Array Biosensor , 2006 .

[20]  Debjani Saha,et al.  Method for homogeneous spotting of antibodies on membranes: application to the sensitive detection of ochratoxin A , 2006, Analytical and bioanalytical chemistry.

[21]  Heidi R. C. Dietrich,et al.  Biosensors and multiple mycotoxin analysis , 2003 .

[22]  Arindam Pal,et al.  An analytical device for on-site immunoassay. Demonstration of its applicability in semiquantitative detection of aflatoxin B1 in a batch of samples with ultrahigh sensitivity. , 2004, Analytical chemistry.

[23]  H. S. Hussein,et al.  Toxicity, metabolism, and impact of mycotoxins on humans and animals. , 2001, Toxicology.

[24]  R. Russell M. Paterson,et al.  Aflatoxins contamination in chilli samples from Pakistan , 2007 .

[25]  K. Jørgensen Occurrence of ochratoxin A in commodities and processed food--a review of EU occurrence data. , 2005, Food additives and contaminants.

[26]  Q. Mandeel,et al.  Fungal contamination of some imported spices , 2005, Mycopathologia.

[27]  P. Brereton,et al.  Simultaneous determination of aflatoxins and ochratoxin A in food using a fully automated immunoaffinity column clean-up and liquid chromatography-fluorescence detection. , 2004, Journal of chromatography. A.