Kinetic Study and Photoreactivation of Waterborne Fungal Spores Under Ultraviolet Light

In recent years, disinfection by ultraviolet (UV) light has been the subject of increasing interest, especially in relation to its efficacy against bacteria. However, its impact on fungi has been much less explored. In this study, we focused on investigating how two types of filamentous fungi react to exposure to UV inactivation, using a continuous flow ultraviolet light reactor (FTR-UV) containing a low-pressure mercury lamp. Our main objective was to understand the inactivation and reactivation characteristics of these fungi. To carry out the study, we suspended Aspergillus niger and Penicillium sp. spores in distilled water adjusted to a pH of 7.20 and exposed them to different doses of UV radiation as they passed through the reactor. Subsequently, we analysed the effects of inactivation and possible reactivation of the spores over a 24-h period, under both light and dark conditions. This approach allowed us to obtain detailed data on the efficacy of UV light in inactivating these fungi and to assess the conditions under which they might reactivate, providing a more complete picture of the potential of UV disinfection in the control of filamentous fungi.