|Miklasz Steven D|
Submitted to: Journal of Food Additives & Contaminants
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/10/1995
Publication Date: N/A
Citation: Interpretive Summary: Certain Fusarium molds commonly found on corn produce a group of toxins called the fumonisins, that can sometimes reach levels sufficient to cause disease in livestock. The intact fumonisins are easily degraded under alkaline conditions, among the products of which is a twenty carbon backbone (hydrolyzed FB1, or HFB1). Because of the ubiquitous nature of fumonisin B1 in corn and corn products, the presence of HFB1 in corn that has undergone an alkali treatment (nixtamilization) is suspected. The extent to which HFB1 represents a potential human health hazard is currently a very active area of research. This research was undertaken to develop a sensitive and rapid immunochemical (ELISA) method for the analysis of HFB1 in foods. A monoclonal antibody reactive with HFB1 was produced and used as the basis for an ELISA capable of detecting as little as 5 ng HFB1 per gram of corn (5 ppb). This method, the first of its kind for fumonisin metabolites, will be an important tool in determining human exposure to HFB1 and as an aid for possible risk assessment.
Technical Abstract: Fumonisin B1, a mycotoxin produced by certain Fusarium molds, consists of two tricarballylic acid groups esterified to a 20 carbon backbone. Under alkaline conditions, or through metabolism, the aminopentol backbone, also known as hydrolyzed FB1 (HFB1) can be formed and is itself cytotoxic. Although the occurrence of HFB1 in corn based foods is suspected, because of the ubiquitous nature of FB1 in corn, analytical methods for its detection are difficult. In the present report we describe a monoclonal antibody-based competitive direct enzyme linked immunosorbent assay (CD-ELISA) for the rapid analysis of HFB1 in corn. The concentration required to inhibit enzyme conjugate binding by 50% (IC50) was 36 ng/ml. The limit of detection of the CD-ELISA was 2 ng HFB1/ml, when HFB1 was added in bovine serum albumin-phosphate buffered saline. The antibody also cross reacted with the hydrolysis products of FB2, FB3, and FB4, having IC50's of 331, 174, and 1700 ng/ml respectively. The antibody did not react with the intact fumonisins, sphingosine, sphinganine, or tricarballyic acid. Samples of corn spiked with HFB1 over the range of 5 to 1000 ng/g indicated the CD-ELISA has a limit of detection of 5 ng/g and an IC50 of 41 ng/g in this matrix. The CD-ELISA provides a sensitive and rapid tool for the analysis of corn-based foods for HFB1.