Effect of UV irradiation on quantity and structure of aflatoxins using HPLC, GC/MS and FT-IR techniques

Numerous strategies for the detoxification or inactivation of aflatoxins in food and feedstuffs have been used. The aim of this study was to evaluate effect of ultra-violet irradiation on detoxification of aflatoxin total including aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2) and aflatoxin total (AFT) content in standard solutions and to investigate the structural changes using HPLC, GC/MS and FT-IR techniques. For this purpose standard vials of aflatoxin solutions with concentrations of 1000μg/kg AFB1, 200μg/kg AFB2, 1000μg/kg AFG1, 200μg/kg AFG2 and 2400μg/kg AFTwere treated by UV-irradiation at 366 nm wave-length for 10 minutes. Aflatoxin contents were analyzed by high pressure liquid chromatography (HPLC) method. Results showed that the amount of AFB1, AFB2, AFG1, AFG2 and AFT reduced about 98, 99.5, 99.8, 100 and 99.1% respectively. Although the treatments were done in-vitro situation, but it is estimated that even in model systems, these technique would be efficient. Separation and identification of compounds in samples were done by GC/Ms and column chromatography.The mass spectral data compared well with the literature reports on mass spectralfragmentation patterns. Results on degradation products of AFB1 showed the m/z ion peak at 286 indicating the opening of the lactone ring. The outcome of the study implies that the degraded compounds are nontoxic or much less toxic than the AFB1. This detoxification may be due to the cleavage in the furan and lactone rings on the AFB1 molecule.

کلیدواژه ها:

Aflatoxin ، UV irradiation ، Detoxification ، Mycotoxin structure ، GC/Ms