Determination of Aflatoxin in Processed Dried Cassava Root: Validation of a New Analytical Method for Cassava Flour

Abstract

A new method that uses HPLC with a photochemical reactor for enhanced detection was developed and validated for the determination of aflatoxins in cassava flour. Samples were spiked with a mixture of four aflatoxins at 5, 10, and 20 g/kg mixed with either 1 or 5 g NaCl and extracted with methanolwater (80 20, v/v) by shaking for 10 or 30 min. An immunoaffinity column was used for cleanup. HPLC with postcolumn derivatization, for enhancement of aflatoxin fluorescence, and fluorescence determination were used for quantitation of the toxin concentration. The method was validated for recovery, linearity, and precision at the three concentrations tested. Recovery ranges were 5270, 6985, and 8089 for the spiking levels of 5.0, 10.0, and 20.0 g/kg, respectively. It appears that the amount of salt (NaCl) and the shaking time are critical factors in this method; optimal performance was obtained when 1 g salt was used and the shaking time was 10 min. The good linearity and precision of the method allowed baseline separation from interferences, e.g., coumarins.

Maize Fungal Growth Control with Scopoletin of Cassava Roots Produced in Benin

“…As previously described by Gnonlonfin et al [ 41 ], high concentration (containing up to 242.5 mg/kg of dry matter) of scopoletin was found in cassava chips from BEN 86052. This justifies the use of cassava roots of this variety in the present study.…”

Analysis of the contrast between natural occurrence of toxigenic Aspergilli of the Flavi section and aflatoxin B1 in cassava

“…AFB1 quantification in cassava chip samples was done on site according to the method developed and validated by Gnonlonfin et al (2010). Briefly, each sample (10 g) was extracted with 1 g of sodium chloride and 25 mL of extraction solution [methanol/water (80/20, v/v)] and purified on an Aflatest ® immunoaffinity column (VICAM, Watertown, MA, USA).…”

“…After peeling, cassava was cut into thin slices and inoculated immediately (fresh) or after heat treatment (120°C for 20 min), freezing (-20°C for 2 months) or drying. For this later treatment, cassava chips were processed as previously described (Gnonlonfin et al, 2010). Everyday, the evolution of the water content was followed according to AOAC 934.01 (AOAC, 2000) and 200 g of cassava were used and inoculated as follow.…”

Developments in mycotoxin analysis: an update for 2010-2011

“…Recoveries ranged from 87.7 to 102.2%. A similar method, but with methanol/ water (80:20) extraction, was optimised for aflatoxins in cassava flour and gave recoveries of 52-89% (Gnonlonfin et al, 2010). Afsah-Hejri et al (2011) performed an optimisation study for fluorescence response after postcolumn photochemical derivatisation of AFB 1 , aflatoxin B 2 (AFB 2 ), aflatoxin G 1 (AFG 1 ) and aflatoxin G 2 (AFG 2 ) extracted from peanut and separated on a reversed-phase column with acetonitrile/water/methanol mixtures.…”