title: Cross-reactivity of antibodies with phenolic compounds in pistachios during quantification of ochratoxin A by commercial enzyme-linked immunosorbent assay kits.
abstract: Ochratoxin A (OTA), a nephrotoxic mycotoxin, naturally occurs in wide range of agricultural commodities. Typical screening of OTA involves various enzyme-linked immunosorbent assay (ELISA) methods. Pistachio (Pistacia vera L.) is a rich source of phenolic compounds that may result in a false positive due to structural similarities to OTA. The present study investigated the cross-reactivity profiles of phenolic compounds using two commercial ELISA test kits. High-performance liquid chromatography was used to confirm the concentration of OTA in the pistachio samples and compared with the results obtained from ELISA. When the degree of interaction and 50 % inhibitory concentration of phenolic compounds were determined, the cross-reactivity showed a pattern similar to that observed with the commercial ELSIA kits, although quantitatively different. In addition, the degree of interaction increased with the increasing concentration of phenolic compounds. The ELISA value had stronger correlations with the content of total phenolic compound, gallic acid, and catechin (R(2) = 0.757, 0.732, and 0.729, respectively) compared with epicatechin (R(2) = 0.590). These results suggest that phenolic compounds in pistachio skins may cross-react with the OTA antibody and lead to a false positive or to an overestimation of OTA concentration in ELISA-based tests.
authors.affiliation: School of Food Science, University of Idaho, 875 Perimeter Drive MS 2312, Moscow, Idaho 83844-2312, USA.
authors.forename: Hyun Jung
authors.initials: HJ
authors.lastname: Lee
authors.affiliation: School of Food Science, University of Idaho, 875 Perimeter Drive MS 2312, Moscow, Idaho 83844-2312, USA.
authors.forename: Alexander D
authors.initials: AD
authors.lastname: Meldrum
authors.affiliation: School of Food Science, Washington State University, P.O. Box 646376, Pullman, Washington 99164-6376, USA.
authors.forename: Nicholas
authors.initials: N
authors.lastname: Rivera
authors.affiliation: School of Food Science, University of Idaho, 875 Perimeter Drive MS 2312, Moscow, Idaho 83844-2312, USA. dryu@uidaho.edu.
authors.forename: Dojin
authors.initials: D
authors.lastname: Ryu
mesh_terms: D000906:Antibodies / Q000737:chemistry; D002392:Catechin / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D005707:Gallic Acid / Q000032:analysis; D009183:Mycotoxins / Q000032:analysis*; D009793:Ochratoxins / Q000032:analysis*; D019800:Phenol / Q000032:analysis; D027927:Pistacia / Q000737:chemistry*; D015203:Reproducibility of Results
chemical_list: D000906:Antibodies; D009183:Mycotoxins; D009793:Ochratoxins; C025589:ochratoxin A; D019800:Phenol; D005707:Gallic Acid; D002392:Catechin