| Aspergillus flavus is widely distributed all over the world, and mainly infect peanut, corn and other oil crops,aflatoxin, which is produced by Aspergillus flavus as secondary metabolites is confirmed as the most potent biological toxins in agricultural food. Peanut oil is the main vegetable oil needed for our daily life, which is rich in unsaturated fatty acid and polyphenols. These nutritional and functional components in peanut oil contribute to prevent cardiovascular and cerebrovascular diseases. The peanut is vulnerable to the infection of Aspergillus flavus and A. Parasiticus under the condition of high temperature and high humidity, which may lead to the contamination of aflatoxins in peanut oil when we use the infected peanut as raw material, and it can pose a serious threat to food consumption safety.UV-irradiated is an effective method for removal aflatoxin B1 in peanut oil,but the photodegradation products and safety of peanut oil after UV treatment is still not clear. In this study, the degradation performance of aflatoxin and quality safety of peanut oilwas evaluated, focusing on the degradation of aflatoxin and product identification. The results are listed as follows:1.The efficiency of UV irradiation with 365 nm on aflatoxin B1 detoxification in peanut oil under different treat time and initial concentration were studied. The results show that the content of aflatoxin in peanut oil decreaseed with irradiation time’s extension, the efficiency of aflatoxin B1 detoxification in peanut oil can come up to 95% after 30 min under UV irradiation. At different initial concentrations, it can be seen that the initial concentration of 128 ppb showed only a little better degradation efficiency than others before 20 min, and then the degradation rate remained around 95% the after 20 min. It was revealed that the effect of the initial concentration of AFB1 in our selected range on degradation activity was unremarkable.2.The degradation products of AFB1 were extracted by methanol and deionized water(V:V=1:9),and analysed by Ultra Performance Liquid Chromatography-Q Exactive Focus Single Stage-Orbitrap Mass Spectrum. Data obtained after accurate structure characterization and derivation of degradation mechanism revealed that two products(C18H33N3O3 and C12H22N2O2) were formed after a more complex series of reactions including modification of double bond in terminal furan ring andfracture of lactone ring, and the small molecular especially nitrogen-containing compoundparticipated in the photochemical reaction in peanuts oil. According to above result, the possible photodegradation pathway of AFB1 in peanut oil was proposed.3.The change of different quality indexes(such as acid value, iodine value, oxidative stability,peroxide value and total phenols content) were detected and evaluated during UV irradiation processing and storage life.The results show that UV irradiation has little impact on the quality of peanut oil.4.In order to evaluate the safety of UV-irradiation detoxification technology, the cell viability test was used to detect AFB1 and its photodegradation products, the results show that the cell viability with AFB1 treated cell gradually reduce over time. The photodegradation products of AFB1 have no significant toxic effect on cell, and the cell viability has noticeable difference compared to untreated cells. |
PDF Full Text Request