3. Results and discussion
3.1. VFA production by alginate fermentation using mixed cultivation system
As mentioned in the materials and methods, the inoculum of alginate fermentation was the effluent from a CSTR. In fact, the CSTR was a VFA-producing system which can continuously pro-duce acetate, propionate and butyrate using L. japonica as sole car-bon source without adding any other nutrients. This system has been operated for over 1000 d in our previous research and stabi-lized more than 600 d. Therefore, the microbial community in the effluent from the CSTR was quite stable.