Prof. Masayoshi Arai received the Ph.D. degree from Kitasato University (Tokyo Japan) in 1999, and his career as a researcher began from The Kitasato Institute. In the Kitasato Institute, he worked with Dr. Satoshi Omura, who was awarded the Nobel Prize in Physiology or Medicine in 2015, and studied bioactive natural products from terrestrial microorganisms. In 2004, he moved to Albert Einstein College of Medicine (NY, USA) as a Postdoctoral Fellow in Dr. William R. Jacobs Jr. Lab., and studied the target molecule of isoniazid, anti-tuberculosis drug. In 2007, he was appointed as a faculty member at Osaka University and was promoted to current position in 2020. After moving to Osaka University, he got a license for diving (!), and has started to search bioactive compounds, especially anti-tuberculosis and anti-cancer substances, from marine organisms and marine-derived microorganisms. His research interests also include the target identification of isolated bioactive compounds using the technique of chemical biology.