Development of an Enzyme-Linked Immunosorbent Assay Method Specific for the Detection of G-Group Aflatoxins

Toxins

Peiwu Li¹  Qian Zhou¹  Ting Wang¹  Haiyan Zhou¹  Wen Zhang¹  Xiaoxia Ding¹  Zhaowei Zhang¹  Perng-Kuang Chang²  Qi Zhang¹  Michelangelo Pascale³ 

[1] Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China;Southern Regional Research Center, Agricultural Research Service, U.S. Department of Agriculture, New Orleans, LA 70124, USA;;Oil Crops Research Institute of the Chinese Academy of Agricultural Sciences, Wuhan 430062, China

关键词: aflatoxin G₁;    class-specific;    monoclonal antibody;    ELISA;    Aspergillus flavus;   

DOI  :  10.3390/toxins8010005

来源: mdpi

【 摘 要 】

To detect and monitor G-group aflatoxins in agricultural products, we generated class-specific monoclonal antibodies that specifically recognized aflatoxins G₁ and G₂. Of the final three positive and stable hybridomas obtained, clone 2G6 produced a monoclonal antibody that had equal sensitivity to aflatoxins G₁ and G₂, and did not cross-react with aflatoxins B₁, B₂, or M₁. Its IC₅₀ values for aflatoxins G₁ and G₂ were 17.18 ng·mL⁻¹ and 19.75 ng·mL⁻¹, respectively. Using this new monoclonal antibody, we developed a competitive indirect enzyme-linked immunosorbent assay (CI-ELISA); the method had a limit of detection of 0.06 ng·mL⁻¹. To validate this CI-ELISA, we spiked uncontaminated peanut samples with various amounts of aflatoxins G₁ and G₂ and compared recovery rates with those determined by a standard HPLC method. The recovery rates of the CI-ELISA ranging from 94% to 103% were comparable to those of the HPLC (92% to 102%). We also used both methods to determine the amounts of G-group aflatoxins in five peanut samples contaminated by aflatoxin B₁-positive, and their relative standard deviations ranged from 8.4% to 17.7% (under 20%), which demonstrates a good correlation between the two methods. We further used this CI-ELISA to assess the ability of 126 fungal strains isolated from peanuts or field soils to produce G-group aflatoxins. Among these, seven stains producing different amounts of G-group aflatoxins were identified. Our results showed that the monoclonal antibody 2 G6-based CI-ELISA was suitable for the detection of G-group aflatoxins present in peanuts and also those produced by fungi.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.