Screening And Identification Of Microorganisms For Water Purification In The Aquaculture Of Sea Cucumber

With the rapid development of the aquaculture industry in our country,pollution and accumulated harmful substances in aquaculture water should be highly concerned,which caused by excretion of aquaculture organisms and degradation of unconsumed aquatic feed.Therefore,it is the hotspot that how to regulate water quality of aquaculture effectively in wastewater treatment currently.Marine microorganisms have their own unique advantages because of the diversities and uniqueness of the marine environment.The efficiently stains for the water of marine microorganisms are more compatibility and security in application of aquaculture.And screening of treating microorganism for aquaculture water could provide a new train of thought for wastewater treatment and optional strains of purifing water quality in actual production.In this project,four strains of photosynthetic bacteria and four stains of heterotrophic nitrifier were isolated,which were screened and rescreened from the aquaculture water and sludge of sea cucumber in the sea of DaLian,China.And down to purify the aquaculture water of sea cucumber,respectively.The photoSynthetic baceria strain HS-PSB1 and heterotrophic nitrifier HS-NOB2 strain were isolated by measuring removal rate of nitrite nitrogen,ammonium nitrogen and COD,which of treating efficiently for aquaculture water of sea cucumber.The removal rate of nitrite nitrogen,ammonia nitrogen and COD for HS-PSB1 were 35.71%,36.22%and 23.81%,respectively.The removal rate of nitrite nitrogen,ammonia nitrogen and COD for HS-NOB2 were 39.62%,41.68%and 20.98%,respectively.Based on the morphological and 16S rDNA sequence analysis,the strain HS-PSB1 was identified as Kocuria sediminis.,the strain HS-NOB2 was identified as Arthrobacter sp.,which were named asKocuria sediminis.HS-PSB1,Arthrobacter sp.HS-NOB2,respectively.The culture of the strain HS-NOB2 was immobilized with 3%sodium alginate in order to study its removal rate of nitrite nitrogen and ammonia nitrogen in aquaculture water of sea cucumber and artificial wastewater.Compared the immobilized HS-NOB2 to the free cells in treatment of wastewater,the results showed that the removal rate of nitrite nitrogen and ammonia nitrogen for immobilization was 49.85%and 56.58%,respectively,which is higher than the free cells.