title: Effect of linear alkylbenzene sulfonate on Cu(2+) removal by Spirulina platensis strain (FACHB-834).
abstract: The removal efficiency of Cu(2+) by Spirulina platensis (strain FACHB-834), in viable and heat-inactivated forms, was investigated in the presence and absence of linear alkylbenzene sulfonate (LAS). When the initial Cu(2+) concentration was in the range of 0.5-1.5 mg · L(-1) , a slight increase in growth rate of FACHB-834 was observed. In contrast, when Cu(2+) or LAS concentrations were at or higher than 2.0 or 6.0 mg · L(-1) , respectively, the growth of FACHB-834 was inhibited and displayed yellowing and fragmentation of filaments. The presence of LAS improved Cu(2+) removal by ~20%, and accelerated attainment of Cu(2+) retention equilibrium. For the 2- mg · L(-1) Cu(2+) treatments, retention equilibrium occurred within 2 d and showed maximum Cu(2+) removal of 1.83 mg · L(-1) . In the presence of LAS, the ratio of extracellular bound Cu(2+) to intracellular Cu(2+) taken up by the cells was lower (1.05-2.26) than corresponding ratios (2.46-7.85) in the absence of LAS. The percentages of extracellular bound Cu(2+) to total Cu(2+) removal (both bound and taken up by cells) in the presence of LAS ranged from 51.2% to 69.3%, which was lower than their corresponding percentages (71.1%-88.7%) in the absence of LAS. LAS promoted biologically active transport of the extracellular bound form of Cu(2+) into the cell. In contrast, the addition of LAS did not increase the maximum removal efficiency of Cu(2+) (61.4% ± 5.6%) by heat-inactivated cells compared to that of living cells (59.6% ± 6.0%). These results provide a theoretical foundation for designing bioremediation strategies using FACHB-834 for use in surface waters contaminated by both heavy metals and LAS.
authors.affiliation: College of Life Sciences, Wenzhou Medical University, Wenzhou, 325035, China.
authors.forename: Huili
authors.initials: H
authors.lastname: Wang
authors.affiliation: College of Life Sciences, Wenzhou Medical University, Wenzhou, 325035, China.
authors.forename: Xiaokai
authors.initials: X
authors.lastname: Zhao
authors.affiliation: Institute of Wenzhou Applied Technology for Environmental Research, Wenzhou Medical University, Wenzhou, 325035, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Fang
authors.affiliation: Department of Land, Air and Water Resources, University of California, Davis, California, 95616, USA.
authors.forename: Randy A
authors.initials: RA
authors.lastname: Dahlgren
authors.affiliation: College of Life Sciences, Wenzhou Medical University, Wenzhou, 325035, China.
authors.forename: Dong
authors.initials: D
authors.lastname: Li
authors.affiliation: Institute of Wenzhou Applied Technology for Environmental Research, Wenzhou Medical University, Wenzhou, 325035, China.
authors.forename: Xiaohan
authors.initials: X
authors.lastname: Yin
authors.affiliation: Institute of Wenzhou Applied Technology for Environmental Research, Wenzhou Medical University, Wenzhou, 325035, China.
authors.forename: Yuna
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Institute of Wenzhou Applied Technology for Environmental Research, Wenzhou Medical University, Wenzhou, 325035, China.
authors.forename: Xuedong
authors.initials: X
authors.lastname: Wang
keywords: Cu2+; FACHB-834; extracellular bound; heat-inactivated cells; intracellular uptake; linear alkylbenzene sulfonate; removal efficiency