Food Biosciences and Technology Program, Department of Agricultural and Environmental Sciences, College of Agriculture, Tennessee State University, Nashville, TN, 37209, USA.
Department of Pharmaceutical Sciences, Department of Chemistry and Biochemistry, Lipscomb University, Nashville, TN, 37204, USA.
Sci Rep. 2020 Aug 10;10(1):13473. doi: 10.1038/s41598-020-70370-x.
The efficacy of a UV-A light emitting diode system (LED) to reduce the concentrations of aflatoxin B, aflatoxin M (AFB, AFM) in pure water was studied. This work investigates and reveals the kinetics and main mechanism(s) responsible for the destruction of aflatoxins in pure water and assesses the cytotoxicity in liver hepatocellular cells. Irradiation experiments were conducted using an LED system operating at 365 nm (monochromatic wave-length). Known concentrations of aflatoxins were spiked in water and irradiated at UV-A doses ranging from 0 to 1,200 mJ/cm. The concentration of AFB and AFM was determined by HPLC with fluorescence detection. LC-MS/MS product ion scans were used to identify and semi-quantify degraded products of AFB and AFM. It was observed that UV-A irradiation significantly reduced aflatoxins in pure water. In comparison to control, at dose of 1,200 mJ/cm UV-A irradiation reduced AFB and AFM concentrations by 70 ± 0.27 and 84 ± 1.95%, respectively. We hypothesize that the formation of reactive species initiated by UV-A light may have caused photolysis of AFB and AFM molecules in water. 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 UV-A dose of 1,200 mJ/cm. Further results from this study will be used to compare aflatoxins detoxification kinetics and mechanisms involved in liquid foods such as milk and vegetable oils.
研究了紫外发光二极管（LED）系统降低纯水中黄曲霉毒素 B（AFB）、黄曲霉毒素 M（AFM）浓度的功效。本研究调查并揭示了黄曲霉毒素在纯水中破坏的动力学和主要机制，并评估了对肝原代细胞的细胞毒性。使用波长为 365nm 的 LED 系统进行辐照实验。将已知浓度的黄曲霉毒素加入水中，用紫外-A 剂量辐照，剂量范围为 0 至 1200mJ/cm。通过高效液相色谱法（HPLC）荧光检测测定 AFB 和 AFM 的浓度。使用 LC-MS/MS 产物离子扫描鉴定和半定量分析 AFB 和 AFM 的降解产物。结果表明，紫外-A 辐照可显著降低纯水中的黄曲霉毒素。与对照相比，在 1200mJ/cm 的紫外-A 辐照下，AFB 和 AFM 的浓度分别降低了 70 ± 0.27%和 84 ± 1.95%。我们假设紫外-A 光引发的活性物质的形成可能导致了水中 AFB 和 AFM 分子的光解。在细胞培养研究中，我们的结果表明，紫外-A 剂量的增加降低了黄曲霉毒素诱导的 HepG2 细胞的细胞毒性，而在 1200mJ/cm 的紫外-A 剂量下未观察到明显的黄曲霉毒素诱导的细胞毒性。本研究的进一步结果将用于比较牛奶和植物油等液体食品中黄曲霉毒素解毒的动力学和机制。
