A study of the stability of AflatoxinB1 to several solutions through fluorescence spectral experiment

AflatoxinBl was extracted from rice contaminated artificially with Aspergillus flavus by using methanol-water (50:50 v/v). As experiment group, sodium chloride were added into the extracted solution of AfBl, comparing with the extracted solution of AfB1, the excitation wavelength of 365 nm under the fluorescence mode were added to two group of solution of AfB1, and the emission spectrum peak at 440 nm were observed. To study the stability of AflatoxinBl to several alkaline solutions, the solution of alkaline with difference concentration were added into the solution of AfB1 respectively within 15 hours. The results showed that all of three alkaline solutions could decrease the 440 nm emission spectrum peak of solution of AfB1 in varying degrees, the effect to decrease emission spectrum peak of AfB1 is very obviously in sodium hypochlorite (NaCIO), and sodium hydroxide (NaOH) taken second place, whereas in ammonia (NH₃-H₂O), the effect was the most weakest among three alkaline solutions. Moreover, the effects were difference in the same alkaline solutions with difference concentration, hydrochloric acid (HCl) in low concentration were added to this complex AfB1 alkaline solutions, degradability of AfB1 were found to be increased. It is concluded that the stability of AflatoxinBl may be affected by alkaline solutions according to their concentration and be degraded greatly by acid addition.