Removal of toxic compounds by a defined actinobacteria consortium

SINELI, PEDRO EUGENIO; BENIMELI, CLAUDIA SUSANA; ANTEZANA, PABLO EDMUNDO; APARICIO, JUAN DANIEL; FUENTES, MARÍA SOLEDAD; COLIN, VERÓNICA LETICIA; BRICEÑO, GABRIELA

Pucón - Cautín

Taller; III Taller Latinoamericano de PGPR y II Simposio de Biotecnología y Medioambiente; 2016

The continued human development increased the simultaneous presence of multiple contaminants in the environment. The ultimate goal of remediation is to protect human health and the environment. Among the remediation techniques, the bioremediation is a promising tool, which used together to metabolically versatile microorganisms such as actinobacteria, represents an interesting strategy for environmental clean-up. The aim of this work was evaluate the ability of an actinobacteria consortium to remove phenanthrene (Ph), lindane (γ-HCH) or Cr(VI), from liquid systems. For it, Streptomyces sp. A5, M7, MC1 and Amycolatopsis tucumanensis DSM 45259 previously selected for its ability to tolerate the studied toxic compounds, were used. The strains were simultaneously inoculated as a microbial consortium, in minimal medium added with Ph (0.1 mM), γ-HCH (2 mgL−1) or Cr(VI) (52 μgmL−1), respectively. The cultures were incubated 144 h at 30 ºC, taking samples every 48 h. The residual toxic compounds (μECD-GC, HPLC, colorimetric reagent, 1,5-diphenylcarbazide) and the microbial growth (dry weight) were determined. All tests were carried out in triplicate, with the corresponding controls. The microbial growth detected at the end of the assays was 0.14 ± 0.02 gL-1, 0.57 ± 0.06 gL-1, and 1.55 ± 0.11 gL-1 for Cr(VI), Ph and γ-HCH, respectively. In the presence of Cr(VI), a biomass decline throughout the assay was observed, suggesting a toxic effect of the metal on the consortium growth. The removal percentages detected were 0%, 52.21% and 83.34% for Cr(VI), γ-HCH and Ph respectively. The abiotic removal detected in Ph and γ-HCH controls ranged between 13.5-12.4%. Thus, the biological removal detected was 69.8% for Ph and 39.8% for γ-HCH. Based upon these findings, the studied consortium could represent a promising tool for bioremediation of liquid systems contaminated with organic compounds such as Ph and γ-HCH.