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bioRxiv · 10.1101/2021.03.14.435353

Evaluation of UV-A LED technology on the reduction of spiked aflatoxin B1 and aflatoxin M1 in whole milk: toxicity analysis using liver hepatocellular cells

Kurup, A. H.·Patras, A.·Pendyala, B.·Vergne, M. J.·Bansode, R. R.
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Abstract

The effectiveness of a UV-A light emitting diode system (LED) to reduce the concentrations of aflatoxin B1, aflatoxin M1 (AFB1, AFM1) in whole milk (WM) was investigated. Irradiation experiments were conducted using an LED system operating at 365 nm. Known concentrations of aflatoxins were spiked in WM and irradiated at quantified UV doses which was calculated based on the average volumetric intensity. LC-MS/MS product ion scans were used to identify and semi-quantify photodegraded products of AFB1 and AFM1. It was observed that UV irradiation significantly reduced aflatoxins in WM, p<0.05. In comparison to control, the maximum UV-A exposure reduced AFB1 and AFM1 concentrations to 78.2 {+/-} 2.36 % (at 836 mJ/cm2) and 65.7 {+/-} 1.65% (at 857 mJ/cm2), respectively. In cell culture studies, our results demonstrated that the increase of UV-A dosage decreased the aflatoxins-induced cytotoxicity in HepG2 cells, and no significant aflatoxin-induced cytotoxicity was observed at highest given UV-A irradiation of 777 (AFB1), 838 (AFM1), and 746 (total AFs) mJ/cm2. Sensory quality of product, cytotoxicity, and mutagenicity of UV exposed aflatoxins in WM using animal models is warranted in the future.

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Kurup, A. H., Patras, A., Pendyala, B., Vergne, M. J., Bansode, R. R.. 2021-03-15. Evaluation of UV-A LED technology on the reduction of spiked aflatoxin B1 and aflatoxin M1 in whole milk: toxicity analysis using liver hepatocellular cells. https://doi.org/10.1101/2021.03.14.435353

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