Desenvolvimento de ic-Elisa para o rastreio da contaminação por aflatoxinas na cadeia de produção de amendoim

The objective of this work was to standardize and validate an indirect competitive enzyme-linked immunosorbent assay (ic-Elisa), as a low-cost tool, to monitor the presence of aflatoxin in common and blanched peanuts ( Arachis hypogaea ) in the production chain. The presence of aflatoxin B1, moisture content, and water activity were analyzed in 60 samples of the peanut cultivar Runner IAC 886, from the 2014/2015 and 2015/2016 harvests of the region of Alta Paulista, in the state of Sao Paulo, Brazil. The validation showed an adequate linearity (R 2 = 0.999), and limits of detection and quantification of 1.13 and 3.59 μg kg -1 , respectively. Recovery rates of 104, 102, and 107% at the concentrations of 4, 10, and 20 μg kg -1 aflatoxin B1, respectively, were also recorded. The ic-Elisa showed a good reproducibility with a high-intraday precision, with 1.87% coefficient of variation (CV), and interday precision with 6.75% CV. The moisture content ranged from 4.0 to 7.2% (mean of 5.8%), and the water activity from 0.4848 to 0.6997 (mean of 0.5990) for the tested samples. Aflatoxin B 1 was present in concentrations ranging from 1.13 to 29.2 μg kg -1 , with only two samples (3.3%) exceeding the maximum allowed limit of 20 μg kg -1 . The ic-ELISA developed here is an accessible tool for the rapid monitoring of aflatoxin contamination in the peanut production chain