Dr. Sunja CHO, Associate Professor of Pusan National University, paid a visit to Institute of Hydrobiology, Chinese Academy of Sciences (IHB), on Feb. 9, 2015. During her visit, Dr. Cho gave a lecture with the title of “Nitrogen recovery & microalgal biotechnology—From consuming energy to producing energy”.   

Dr. CHO started her presentation with An Inconvenient Truth, which is a documentary about preventing green-house effect, advocated by Albert Arnold Gore Jr, the 45^th vice-president of United States. She then made introductions of 9 global environmental problems nowadays. Global N&P recycling plays the most vital role in environmental change, because a great amount of nitrogen and phosphorus is responsible for water eutrophication and other environmental issues. Dr. CHO explained the current nitrogen and phosphorus removal process and its limitations. In order to purify waste water, microalgae and bacteria are used in the process and Dr. CHO makes a 3R strategy for waste water.    

The presentation gave a lot of attention on effects of mircoalgae growth in waste water which contains bacteria. The research shows that some bacteria in waste water stimulates microalgae growth in initial stage while has inhibiting effect in late stage. Dr. CHO also hypothesizes that microalgae tend to combine with nitrogen-fixing bacteria when there is no more nitrogen, some bacteria will produce Biofilm on the surface of microalgae to prevent protozoa from eating microalgae and other bacteria can generate Bioemulsifier becoming a round with antagonism of algal-bacterial. This hypothesis caused a heat discussion among researchers and students.   

Since Dr. CHO studied on her research in Pusan National University in 2006, she has been devoting herself into research on nitrogen recycling, molecular microbial ecology, post genomics, and interactions between microalgae and other microorganism. Therefore she published many SCI papers in above-mentioned fields. Dr. CHO was invited to start a cooperative study in Institute of Hydrobiology by CMBB for one and half a month, thus she made an extensive and profound communication with colleagues in the institute.