STUDIES ON STERIGMATOCYSTIN IN SOME WHEAT BASED FOODS

Abstract

Sterigmatocystin (Stg) is a mycotoxin produced by Aspergillus versicolor and Aspergillus nidulans. Stg has been shown to be carcinogenic, causes cancer in number of animal species and classified as class 2B carcinogen (as possibly carcinogenic to humans) by IARC. The results indicated that the developing system Benzene: acetic acid (9: 1 v/v) showed the best separation for small concentrations of Stg when used TLC technique. Moreover the data showed also that the mobile phase methanol: water (8: 2 v/v) succeeded to separate Stg at 5.4 min retention time when the flow rate was 1ml/ min. When comparison between different methods for Stg determination by HPLC in spiked wheat samples. The results cleary indicated that the percentages of loss in AOAC (2000) method were 10.44, 24.55, 17.07 and 28.95% for the tested concentration levels (5, 10, 50 and 100µg) respectively. Moreover the percentage of toxin loss ranged from 93.47 and 96.64% with average of 94.895 in TLC determination and however, it ranged from 10.52 and 27.95% with average of 19.68% in HPLC method