不同氧环境下维生素C对核黄素光化学法灭活血浆中大肠杆菌的影响

The inactivation of Escherichia coli using riboflavin photochemistry combined with vitamin C in different oxygenic atmosphere

目的研究313nm作为激发光时,不同氧环境下维生素C(Vc)对核黄素(Rf)光化学法灭活血浆中大肠杆菌效果的影响。方法将含有50μmol/L的RF和0、12.5、25、37.5和50mmol/L维生素C的混合血浆与大肠杆菌液混合后盛装于12孔培养板、排除空气的PVC储血袋(乏氧)和充加纯氧的PVC储血袋(充氧),用313nm波长紫外光辐照,照射剂量为5J/mL,观察不同氧环境和Vc对RF化学灭活大肠杆菌效果的影响。结果在培养板中Vc有促进RF光化学灭活大肠杆菌的效能;在排除空气的PVC储血袋(乏氧)中,Vc促进RF光化学灭活大肠杆菌的效能的作用明显减弱;与乏氧环境相比较,在充加纯氧的PVC储血袋(充氧)中,Vc有促进RF光化学灭活大肠杆菌的效能,当Vc浓度为10mmol/L时,大肠杆菌的滴度下降4.3log/mL。结论在高含氧环境下Vc联合RF经313nm波长光源照射可有效灭活血浆中的大肠杆菌;Vc作为1种病原体灭活的光化学底物的可能性和可行性值得做进一步深入探讨。

Objective To study the effect of riboflavin（RF） photochemical method on E.coli in plasma using 313nm wavelength combined with vitamin C（Vc） to excite light in different oxygenic environments.Methods 50μmol/L RF and（0,12.5,25 or 37.5mmol/L） of Vc in pooled plasma were mixed with intesfinel E.coli.The mixture was irradiated by 313nm wavelength light in 12 well cultured plates or PVC blood storage bags（oxygen environment or hypoxic environment）.The dose of irradiation was 5J/mL.The inactivation effects on E.coli were observed in different oxygen environments.Results Vc promoted photochemical inactivation of E.coli in 12 well cultured plates.However,the promotion effect of Vc was not obvious in PVC storage bag（due to lack of oxygen）.Compared with the hypoxic environment,Vc was more likely to promote the RF photochemical inactivation of E.coli in the blood storage bag filled with pure oxygen.RF was then irradiated with 313nm wavelength,combined with 10mmol/L Vc,which led to a decrease in titer of E.coli by 4.3log/mL.Conclusion In an environment with high oxygen levels,the combination of RF and Vc irradiated by 313nm wavelength light source can effectively inactivate E.coli in plasma.Vc has the possibility to be one of the photochemical substrates used for pathogen inactivation.