title: Aflatoxin evaluation in ready-to-eat brazil nuts using reversed-phase liquid chromatography and post-column derivatisation.
abstract: A high-performance liquid chromatography-fluorescence (HPLC-FD) method for aflatoxin quantification in brazil nuts was developed. Samples of brazil nuts collected in Brazilian markets were extracted with methanol:water and cleaned using an immunoaffinity column. Aflatoxins were eluted with methanol and a post-column derivatisation was performed with bromine, using a Kobra Cell system. The optimised method for total aflatoxins was sensitive, with detection and quantification limits of 0.05 and 0.25 µg kg⁻¹, respectively. The method was accurate, with recovery values of 87.6%; 85.3% and 85.0% for 0.5, 5.0 and 14.6 µg kg⁻¹ spiked levels, respectively. It was shown that the method was applicable to brazil nuts. From a total of 95 brazil nut samples analysed from 21 São Paulo supermarket samples and 51 Manaus and 23 Belém street markets samples, 37.9% showed detectable levels of aflatoxins and three exceeded the recommended Codex Alimentarius limit of 10 µg kg⁻¹ for ready-to-eat brazil nuts.
authors.affiliation: a Food Technology Institute , Campinas/SP, 13070-178 , Brazil.
authors.forename: Beatriz Thie
authors.initials: BT
authors.lastname: Iamanaka
authors.forename: Felipe
authors.initials: F
authors.lastname: Nakano
authors.forename: Daniel Ponciano
authors.initials: DP
authors.lastname: Lemes
authors.forename: Larissa Souza
authors.initials: LS
authors.lastname: Ferranti
authors.forename: Marta Hiromi
authors.initials: MH
authors.lastname: Taniwaki
mesh_terms: D000348:Aflatoxins / Q000032:analysis*; D053000:Analytic Sample Preparation Methods; D031383:Bertholletia / Q000737:chemistry*; D001938:Brazil; D002273:Carcinogens / Q000032:analysis; D002846:Chromatography, Affinity; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase; D005062:European Union; D057140:Fast Foods / Q000032:analysis* / Q000191:economics / Q000592:standards; D005506:Food Contamination; D005511:Food Handling; D005513:Food Inspection / Q000379:methods*; D019983:Guideline Adherence; D057230:Limit of Detection; D009754:Nuts / Q000737:chemistry* / Q000191:economics / Q000592:standards; D011042:Poisons / Q000032:analysis*; D015203:Reproducibility of Results; D013050:Spectrometry, Fluorescence; D013723:Teratogens / Q000032:analysis
chemical_list: D000348:Aflatoxins; D002273:Carcinogens; D011042:Poisons; D013723:Teratogens
keywords: HPLC; aflatoxins; brazil nuts; immunoaffinity column