TY - JOUR
T1 - Biosorption of cadmium by non-toxic extracellular polymeric substances (EPS) synthesized by bacteria from marine intertidal biofilms
AU - Camacho-Chab, Juan Carlos
AU - Castañeda-Chávez, María del Refugio
AU - Chan-Bacab, Manuel Jesús
AU - Aguila-Ramírez, Ruth Noemí
AU - Galaviz-Villa, Itzel
AU - Bartolo-Pérez, Pascual
AU - Lango-Reynoso, Fabiola
AU - Tabasco-Novelo, Carolina
AU - Gaylarde, Christine
AU - Ortega-Morales, Benjamín Otto
N1 - Funding Information:
Acknowledgments: Juan Carlos Camacho-Chab was funded for a research stay in the “Laboratorio Nacional de Nano y Biomateriales, Cinvestav Unidad Mérida” by a Ph.D. grant provided by CONACYT within the program “Becas Mixtas”. The authors are grateful to Wilian J. Cauich Ruiz for his invaluable help in the X-ray analysis.
Publisher Copyright:
© 2018 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2018/2/11
Y1 - 2018/2/11
N2 - Cadmium is a major heavy metal found in polluted aquatic environments, mainly derived from industrial production processes. We evaluated the biosorption of solubilized Cd2+ using the extracellular polymeric substances (EPS) produced by Bacillus sp. MC3B-22 and Microbacterium sp. MC3B-10 (Microbactan); these bacteria were originally isolated from intertidal biofilms off the coast of Campeche, Mexico. EPS were incubated with different concentrations of cadmium in ultrapure water. Residual Cd2+ concentrations were determined by Inductive Coupled Plasma-Optic Emission Spectrometry and the maximum sorption capacity (Qmax) was calculated according to the Langmuir model. EPS were characterized by X-ray photoelectron spectroscopy (XPS) before and after sorption. The Qmax of Cd2+ was 97 mg g−1 for Microbactan and 141 mg g−1 for MC3B-22 EPS, these adsorption levels being significantly higher than previously reported for other microbial EPS. In addition, XPS analysis revealed changes in structure of EPS after biosorption and showed that amino functional groups contributed to the binding of Cd2+, unlike other studies that show the carbohydrate fraction is responsible for this activity. This work expands the current view of bacterial species capable of synthesizing EPS with biosorbent potential for cadmium and provides evidence that different chemical moieties, other than carbohydrates, participate in this process.
AB - Cadmium is a major heavy metal found in polluted aquatic environments, mainly derived from industrial production processes. We evaluated the biosorption of solubilized Cd2+ using the extracellular polymeric substances (EPS) produced by Bacillus sp. MC3B-22 and Microbacterium sp. MC3B-10 (Microbactan); these bacteria were originally isolated from intertidal biofilms off the coast of Campeche, Mexico. EPS were incubated with different concentrations of cadmium in ultrapure water. Residual Cd2+ concentrations were determined by Inductive Coupled Plasma-Optic Emission Spectrometry and the maximum sorption capacity (Qmax) was calculated according to the Langmuir model. EPS were characterized by X-ray photoelectron spectroscopy (XPS) before and after sorption. The Qmax of Cd2+ was 97 mg g−1 for Microbactan and 141 mg g−1 for MC3B-22 EPS, these adsorption levels being significantly higher than previously reported for other microbial EPS. In addition, XPS analysis revealed changes in structure of EPS after biosorption and showed that amino functional groups contributed to the binding of Cd2+, unlike other studies that show the carbohydrate fraction is responsible for this activity. This work expands the current view of bacterial species capable of synthesizing EPS with biosorbent potential for cadmium and provides evidence that different chemical moieties, other than carbohydrates, participate in this process.
KW - Aquatic environments
KW - Bioremediation
KW - Biosorption
KW - Cadmium
KW - Extracellular polymeric substances
UR - http://www.scopus.com/inward/record.url?scp=85041947029&partnerID=8YFLogxK
U2 - 10.3390/ijerph15020314
DO - 10.3390/ijerph15020314
M3 - Artículo
C2 - 29439486
AN - SCOPUS:85041947029
SN - 1661-7827
VL - 15
JO - International Journal of Environmental Research and Public Health
JF - International Journal of Environmental Research and Public Health
IS - 2
M1 - 314
ER -