Development of monoclonal antibodies for the fusarin mycotoxins

Abstract

The fusarins are a group of mycotoxins produced by fungi that commonly infest cereal crops, in particular by the fungus Fusarium verticillioides. This group of compounds is characterized by a substituted 2-pyrrolidone ring attached to a 12-carbon polyunsaturated backbone. Several of the fusarins contain an epoxide substitution on the pyrrolidone ring and are highly mutagenic. This paper describes the development of seven monoclonal antibodies and immunoassays for detecting fusarins C and A. Fusarin C was isolated and conjugated to ovalbumin to produce the immunogen. Competitive indirect enzyme-linked immunosorbent assays (CI-ELISAs) were developed based upon the isolated monoclonal antibodies. The concentrations of fusarin C able to inhibit colour development by 50% (IC₅₀) in CI-ELISAs were 1.0, 2.0, 3.6, 23.4, 28.9, 31.4, and 66.7 ng ml⁻¹ for clones 1–38, 1–30, 1–5, 1–7, 1–43, 1–25, and 1–21, respectively. Cross-reactivity with fusarin A was 44.8, 51.4, 41.1, 174.0, 62.6, 78.2, and 98.0% for clones 1–38, 1–30, 1–5, 1–7, 1–43, 1–25, and 1–21, respectively. Given the sensitivity of these antibodies for fusarins it is expected that, with further development, they may be useful for detecting fusarins at relevant levels in foods.

Keywords:

• Fusarin
• mycotoxin
• antibody
• immunoassay
• Fusarium verticillioides

Acknowledgements

The authors wish to express their appreciation to Ms Renee Wartner and Ms Shannon Snodgrass of Harlan Bioproducts for Science, and Mr John Bobell and Ms Debbie Shane of USDA-NCAUR for the exceptional quality of the technical assistance provided throughout this project. Mention of trade names or commercial products in this paper is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the US Department of Agriculture.