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In order to improve the quality of natural seawater to meet the needs of aquaculture production, a large-scale subsurface flow constructed wetland was constructed and operated stably for 2 years to study its purification effect on natural seawater. Studies had shown that the system could maintain high purification effect on natural seawater during aquaculture, and could effectively remove harmful algae such as Cyanobacteria, especially in warm months. The pyrosequencing of 16S ribosomal DNA revealed that Proteobacteria, Nitrospirae, chloroflexi were the main and key bacterial phyla in the system. Members of these key gates were regarded as the important roles in resisting water purification. In summary, the subsurface flow wetland system was suitable for large-scale seawater aquaculture plants, which could effectively improve seawater quality conditions and reduced the density of harmful algae cells.

The energy cost and the harm of the residual chlorine by-produced in the electrochemical processes are main hinders for the extensive use of the electrochemical recirculating aquaculture systems (ERAS). The present study conducted shrimp-culture experiments using pilot electrochemical systems to investigate the effects of current density, geometric feature, timing, and other parameters on the effective control of inorganic nitrogen, pathogens, and residual chlorine in aquaculture water. The 50-L electrochemical batch reactor, which featured 154 cm2 (area) of Ti-RuO2 / Ti electrodes and 66 mA/cm2 of current density, eliminated inorganic nitrogen and Vibrio in rearing seawater collected from a shrimp farm with an initial ammonia concentration of 1.2–4.0 mg/L in 5 min. Air strippings were used to resolve residual chlorine derived from electrooxidation, finding hypochlorous acid decreased from 5.0 mg/L initially to 2.5 mg/L in 2 h of continuous of air aeration to the batch reactor. In the experiments of shrimp culture, The ERAS equipped with a 50-L batch reactor and 500-L shrimp tank effectively keep the inorganic nitrogen concentration in rearing water as required when applying 4.3 g of nitrogen loads transformed from a daily quota of commercial prawn feeds. By precisely controlling the times of intermittent processes of electrooxidation and air stripping, an electrochemical recirculating aquaculture system can achieve both the removal of inorganic nitrogen and residual chlorine, disinfection and reduction of energy cost.

Coumarin is a kind of lactone compound with skeleton of benzo-alpha-pyranones, which have favorable druggability due to its advantages of outstanding pharmacological activities, little drug-resistance, lowtoxicity, simple skeleton, easy synthesis and structural modification, and extensive sources. The review summarizes the classification, synthesis methods, pharmacological effects of coumarin and its derivatives. It focuses on their latest progresses in anti-bacteria, anti-virus, anti-inflammation and anti-rheumatism, anti-autoimmune diseases, anti-oxidation, anti-coagulation, anti-cancer and antiangiogenic effects in detail. Especially, coumarins exhibited outstanding effects on clinical difficult miscellaneous diseases with rare drugs, difficult cure and bad prognosis, such as coronavirus disease-19, rheumatoid arthritis, autoimmune neuroinflammation, systemic lupus erythematosus, idiopathic pulmonary fibrosis, etc. The review would provide new skeletons and promising lead compounds with little drug-resistance, high-efficiency and lowtoxicity for new drug development for related diseases based on coumarins.