The sample preparation and analysis was done according to
our previously validated method (Iqbal, Asi, et al., 2013; Iqbal,
Bhatti, et al., 2013). The sample of 25 g was taken in a flask
containing 100 ml of acetonitrile: water (86:14; v/v) and 2.5 g of
sodium chloride. The sample was blended 5 min at a high speed
and then the solution was filtered with Whatman no. 5 filter
papers. After filtration, 5 ml of the filtrate was diluted with deionized
water (20 ml) and then it passed through an IAC at a
flow rate of 1.0 ml/min. AFs were eluted from the column by
applying 1.5 ml of methanol and the extract was evaporated to
dryness under nitrogen stream at 40 C. The derivatization of
AFB1 and AFG1 was done by adding 100 ml of TFA to the residue
or AFs standards. After that, the samples were kept in the dark at
room temperature for 20 min. Finally, 400 ml mixture of acetonitrile:
water (1:9, v/v) was added and 20 ml was subjected to
HPLC analysis.