Metoxychlor Biodegradation by Defined Consortia of Indigenous Streptomyces Strains

FUENTES, M. SOLEDAD; ALVAREZ ANALÍA; SAEZ, JULIANA M.; BENIMELI CLAUDIA S.; AMOROSO MARÍA JULIA

INTERNATIONAL JOURNAL OF ENVIRONMENTAL SCIENCE AND TECHNOLOGY

CTR ENVIRONMENT & ENERGY RESEARCH & STUDIES

Año: 2013 vol. 11 p. 1147 - 1156

1735-1472

Methoxychlor is an organochlorine pesticideused worldwide against several insect pests, resulting inhuman exposure. This pesticide mimics endocrine hormonefunctions, interfering with normal endocrine activity inhumans and wildlife. For this reason, it is imperative todevelop methods to remove this pesticide from the environment, and though, bioremediation using microorganisms results as an excellent strategy. Five Streptomycesspp. strains previously isolated from organochlorine-polluted sites and capable to grow and remove methoxychlorwere combined as different mixed cultures to increasemethoxychlor removal. From the 39 consortia tested, oneconsortium (Streptomycesspp. A6, A12, A14, M7) wasselected because of its high pesticide removal and specificdechlorinase activity to be assayed on slurry and soil systems. This consortium showed higher biomass values(8.3 9106±5.79105CFU mL-1) and methoxychlorremoval (56.2 ±2.3 %) on enriched slurry than in nonenriched slurry (7.39105±1.29105CFU mL-1and45.6±7.4 % of pesticide removal). In soil systems,Streptomyces consortium showed higher growth(1.0 91011±5.091010CFU g-1) than in enrichedslurry, although differences in methoxychlor removalbetween both culture conditions were not statistically significant. Therefore, the selectedStreptomycesconsortiummay be suitable for the development of in situ (soil) and exsitu (slurry bioreactor) bioremediation methods because oftheir potential to remove methoxychlor from differentsystems.