Inhibitory Effects Of Tannie Acid On The Growth Of Microcystis Aeruginosa

The occurrences of eutrophication are nowadays in a growing trend in China and algal blooms are becoming increasingly severe environmental problems, which poses great harm to water environment and ecological safety. Conventional algal inhibition method of physical, chemical and biological methods are usually unsatisfactory and likely to cause secondary pollution.This research focuses on the most common alga in water blooms.The study was designed to experiment to select the most appropriate degradation of algal kind of external conditions from the tannic acid concentration,temperature,light,and other aspects.Tannic acid on aquatic plants and animals need to be studied before doing the experiment.Zabra fish are selected to as an object of study to explore the tannic acid removal of Microcysis aeruginosa.The median lethal concentration (LC50) of tannic acid to the Zebra fish treated for96h is55.20mg/L.Safe concentration of Tannic acid on Zebrafish is12.94mg/L,and Tannic acid on zebrafish is low toxicity.The tannic acid effect against Microcystis aeruginosa shows that the concentration of80mg/L tannic acid has the best algae-lysing effect,with a removal rate of over98%within14days in terms of chlorophyll.The concentrationg of30mg/L-60mg/L tannie acid have moderate algae-lysing effects against Microcystis aeruginosa,with chlorophyll removal rates ranging from50%-80%within14days. Extracts from the concentration of less than30mg/L of tannie acid had unsatisfactory algae-lysing effects against Microcystis aeruginosa with chlorophyll a removal rates of less than30%within14days. Tannic acid can inhibit the growth of Microcystis aeruginosa,and Microcystis aeruginosa will not gorw again after being processedResult from the study on the effect of extracts from Microcystis aeruginosa showed that:there are many factors affect the degradation efficiency, in addition to the concentration outside temperature, light conditions.Tannic acid on Microcystis aeruginosa degradation of the best temperature is20℃within20℃～34℃.and the degradation efficiency decreased with increasing temperature. Illumination also have an impact on the degradation of Microcystis aeruginosa.after being processed, culturing the algae in the darkness first can maintain the inhibitory effect.