Hsing Wu University 1 article published in JoVE Bioengineering Inactivation of Pathogens via Visible-Light Photolysis of Riboflavin-5′-Phosphate Chien-Wei Cheng1, Shwu-Yuan Lee2, Tang-Yu Chen1, Jeu-Ming P. Yuann1, Chi-Ming Chiu1, Shiuh-Tsuen Huang3,4, Ji-Yuan Liang1 1Department of Biotechnology, Ming Chuan University, 2Department of Tourism and Leisure, Hsing Wu University, 3Department of Science Education and Application, National Taichung University of Education, 4Department of Soil and Environmental Sciences, National Chung Hsing University Here, we present a protocol to inactivate pathogenic bacteria with reactive oxygen species produced during photolysis of flavin mononucleotide (FMN) under blue and violet light irradiation of low intensity. FMN photolysis is demonstrated to be a simple and safe method for sanitary processes.