To effectively remove n-propylbenzene(n-PBZ)and isopropylbenzene(i-PBZ)leaked into seawater using Rhinomonas reticulata S6A(a newly isolated marine microalga),the effects of three inorganic nutrients and four environm...To effectively remove n-propylbenzene(n-PBZ)and isopropylbenzene(i-PBZ)leaked into seawater using Rhinomonas reticulata S6A(a newly isolated marine microalga),the effects of three inorganic nutrients and four environmental factors on their degradation were determined after 7 d of inoculation.Results show that NaNO_(3) at 300 mg/L caused a higher removal efficiency of both n-PBZ and i-PBZ(44.79%and 39.26%),while for NaH_(2) PO_(4)·H_(2) O,greater removal rates of two PBZs(47.30%and 42.23%)were achieved at 30 and 20 mg/L,respectively.NaHCO_(3) supplementation(500-750 mg/L)resulted in a large reduction(43.67%-45.04%)in i-PBZ concentration.The change in seawater pH(from 6 to 9)did not affect the elimination of n-PBZ and i-PBZ.The most suitable salinity and temperature were 30 and 25-30℃,respectively,leading to the PBZs removal of~40%.Light intensity exhibited significant influence on elimination of PBZs,and the maximum removal efficiencies of 56.07%(n-PBZ)and 55.00%(i-PBZ)were recorded under 200 and 600μmol/(m^(2)·s),respectively.In addition,the microalga could still remove PBZs when it failed to grow well due to darkness,strong light,low temperature,or low salinity,which might mean that good growth of alga is not always a necessary condition for PBZs removal.Therefore,attention should be paid to the suitability of nutrient levels and environmental conditions(excluding pH)in seawater when using microalgae for bioremediating PBZs-contaminated seawater.展开更多
基金Supported by the National Natural Science Foundation of China(No.42077335)。
文摘To effectively remove n-propylbenzene(n-PBZ)and isopropylbenzene(i-PBZ)leaked into seawater using Rhinomonas reticulata S6A(a newly isolated marine microalga),the effects of three inorganic nutrients and four environmental factors on their degradation were determined after 7 d of inoculation.Results show that NaNO_(3) at 300 mg/L caused a higher removal efficiency of both n-PBZ and i-PBZ(44.79%and 39.26%),while for NaH_(2) PO_(4)·H_(2) O,greater removal rates of two PBZs(47.30%and 42.23%)were achieved at 30 and 20 mg/L,respectively.NaHCO_(3) supplementation(500-750 mg/L)resulted in a large reduction(43.67%-45.04%)in i-PBZ concentration.The change in seawater pH(from 6 to 9)did not affect the elimination of n-PBZ and i-PBZ.The most suitable salinity and temperature were 30 and 25-30℃,respectively,leading to the PBZs removal of~40%.Light intensity exhibited significant influence on elimination of PBZs,and the maximum removal efficiencies of 56.07%(n-PBZ)and 55.00%(i-PBZ)were recorded under 200 and 600μmol/(m^(2)·s),respectively.In addition,the microalga could still remove PBZs when it failed to grow well due to darkness,strong light,low temperature,or low salinity,which might mean that good growth of alga is not always a necessary condition for PBZs removal.Therefore,attention should be paid to the suitability of nutrient levels and environmental conditions(excluding pH)in seawater when using microalgae for bioremediating PBZs-contaminated seawater.