Inhibition of aflatoxin B1 production of Aspergillus flavus isolated from peanut seeds using Lycium halimifolium Mill leaves fractions

The aim of this study is to explore the impact of Lycium halimifolium Mill leaves extracts on mycotoxin B1 production in vitro, as well as the inhibitor effect of the aflatoxin B1 synthesis by Aspergillus flavus strain. The strain was isolated, identified (gi |146746162 | EF409803.1.) and positively tested for the production of Aflatoxin B1. The antimycotoxinogenesis effect was investigated using L. halimifolium Mill leaves consisting of butanol and ethyl acetate fractions. Indeed, the fractions were tested to stop the secretion of aflatoxin B1 by A. flavus in submerged culture (YES), simultaneously. The growth of the strain was evaluated as biomass response. The antimycotoxinogenesis activity showed that the two fractions: ethyl acetate and butanol of L. halimifolium Mill leaves were able to inhibit significantly the synthesis of mycotoxin AFB1. Thus, the secretion inhibition percentage was calculated in comparison with the control, using HPLC-PDA technique, and estimated at 96.83% for butanolic fraction and 94.99% for ethyl acetate fraction. To verify its correlation with biomass, the growth inhibition percentage was also estimated. The results showed that the dry weight concentration under butanolic and ethyl acetate fractions was 1.6 and 2 g/l, respectively, corresponding to 65.22 and 56.53% of inhibition growth percentage. Key words: Aflatoxin B1, antimycotoxinogenesis activity, high performance liquid chromatography coupled with photodiode array detector (HPLC-PDA), natural extract.