Captación de lindano por streptomycetes acuáticos regionales

CLAUDIA S. BENIMELI; ADRIANA P. CHAILE; GUILLERMO OLIVER; MARÍA J. AMOROSO

Tafí del Valle, Tucumán, Argentina

Jornada; XIX Jornadas Científicas Asociación de Biología de Tucumán; 2002

Asociación de Biología de Tucumán

Lindane, an organochlorine pesticide, has been extensively used for the control of agricultural and medical pests. Streptomycetes, one of the main groups of bacteria in the soil and sediments, are Gram (+) and have a great potential for the biodegradation of organic and inorganic toxic compounds. The aim of this work is to determine if the removal lindane capacity by a regional aquatic streptomycete strain (M7) is carried out for degradation mechanisms or by accumulation in the cellular biomass. M7 was used for their capacity to growth in presence of lindane in a minimal medium (MM) and to remove it to the medium. M7 was previously adapted in glucose and lindane respectively and cultivated in MM added of glucose 10 g l-1 plus lindane 10 µg l-1, 96 h at 30ºC. Residual lindane was measured in supernatants samples and in the cellular biomass by gas chromatography; previously, extractions in solid phase and with ethyl acetate were made. When M7 was previously adapted in glucose the strain removed 55% of the compound until 48 h of incubation; the appearance of a pick corresponding to lindane was observed at 24 h of incubation inside cellular biomass. A diminished of 53% in this concentration was obtained after 48 h of incubation. When M7 was previously adapted in lindane, they were observed similar results in the supernatants, but in bacterial cells the decrease of the pesticide was 72% after 96 h of incubation. These results suggest that the streptomycete M7 is able to remove lindane of the medium by degradation mechanisms present in the bacterial cell.