Determination of Aflatoxin B1 in Medical Herbs: Interlaboratory Study

Abstract

A method was developed for the determination of aflatoxin B1 in medical herbs (senna pods, botanical name Cassia angustifolia; devil's claw, botanical name Harpagophytum procumbens; and ginger roots, botanical name Zingiber officinale). The method, which was tested in a mini-collaborative study by 4 laboratories, is based on an immunoaffinity cleanup followed by reversed-phase high-performance liquid chromatography separation and fluorescence detection after post-column derivatization. It allows the quantitation of aflatoxin B1 at levels lower than 2 ng/g. A second extractant (acetonewater) was tested and compared to the proposed methanolwater extractant. Several post-column derivatization options (electrochemically generated bromine, photochemical reaction, and chemical bromination) as well as different integration modes (height versus area) were also investigated. No differences were found depending on the choice of derivatization system or the signal integration mode used. The method was tested for 3 different matrixes: senna pods, ginger root, and devil's claw. Performance characteristics were established from the results of the study and resulted in HorRat values ranging from 0.12 to 0.75 with mean recoveries from 78 to 91% for the extraction with methanolwater and HorRat values ranging from 0.101.03 with mean recoveries from 98 to 103% for the extraction with acetonewater. As a result, the method, with all tested variations, was found to be fit-for-purpose for the determination of aflatoxin B1 in medical herbs at levels of 1 g/kg and above.

Incidence and Level of Aflatoxins Contamination in Medicinal Plants in Korea

“…In this study, the average recoveries of AFB1, AFB2, AFG1, and AFG2 were 91.2%, 94.0%, 95.5%, and 87.7%, respectively. Romagnoli et al [ 16 ], Arranz et al [ 17 ] and Zhang et al [ 18 ] previously obtained the ranges of 76.1~78.1%, 98~103%, and 93~97%, respectively, which were different from the results obtained in the present study. Reiter et al [ 6 ] reported that the recovery of aflatoxins depends on the type of substrate, purification method, and type of device used for derivatization.…”

Methods for Detection of Aflatoxins in Agricultural Food Crops

“…Thus, the extraction of aflatoxins involves the use of these organic solvents such as either methanol or acetonitrile or acetone mixed in different proportion with small amounts of water [46,47]. Several studies exploring the extraction efficiency of different organic-aqueous solvents have been carried out on the commonly contaminated matrices [48][49][50] and different results have been reported. Aflatoxin determination based on immunoassay technique requires extraction using mixture of methanol-water (8 + 2 v/v) [48,51] because methanol has less negative effect on antibodies compared to other organic solvents such as acetone and acetonitrile.…”

Effect of the inclusion of adsorbents on aflatoxin B1quantification in animal feedstuffs

“…In 48 dairy farms, the precise AFB 1 determination in animal feeds is useful to predict the AFM 1 49 concentration in milk and to avoid contamination levels exceeding the legal limits. 50 (Trucksess and Wood, 1994;Stroka et al, 1999), such as 52 enzyme linked immunosorbent assay (ELISA) (Aldao et al, 1995), HPLC (Sharma and Marquez, 53 2001;Stroka et al, 2003;Arranz et al, 2006) or TLC (Bradburn et al, 1995). All these techniques need 54 an efficient sample extraction method.…”

“…All these techniques need 54 an efficient sample extraction method. Several studies have been conducted to investigate the 55 extraction capacity of different organic/aqueous solvents, like methanol (Reif and Metzger, 1995;Stroka et al, 1999;Sharma and Marquez, 2001;Senyuva and Gilbert, 2005;Brera et al, 2007), acetone 57 (Brandurn et al, 1995;Stroka et al, 2003;Arranz et al, 2006), acetonitrile (Stroka et al, 1999) and 58 chloroform (Moller and Nyberg, 2004) solvents. Some studies investigated the organic solvent to water 59 ratio (ml solvent/ml water), the ratio of solvent to sample (ml solvent/g sample) and the matrix effects 60 (Brandburn et al, 1995;Stroka et al, 1999;Moller and Nyberg, 2004).…”