Influence of glucose concentration in the lindane removal by a actinomycete strain

CS BENIMELI; AP CHAILE; MJ AMOROSO; GR CASTRO

Salt Lake City, Utah, USA

Congreso; American Society for Microbiology 102 nd General Meeting; 2002

American Society for Microbiology

Lindane is an organochlorine pesticide and its was been extensively worldwide used for the control of agricultural and medical pests. This insecticide is known for its persistence in the environment, bioaccumulation tendency and toxicity for non-target organisms, including human beings. Lindane was found in main hydrographic system of Tucumán-Argentina, at 2 ppm concentration. It has determinate that actinomycetes are one of the main groups of bacteria in the soil and sediments. These microorganisms are Gram (+) and have a great potential for the biodegradation of organic and inorganic compounds, and also could remove different pesticides when other carbon source is present in the medium. The aim of this work is to determine if the lindane removal capacity by a regional aquatic actinomycete strain can be improved in presence of  glucose. The streptomycete M7 was used for their capacity to grow 40% more in lindane than in glucose in minimal medium (MM). This microorganism was previously adapted in glucose and lindane respectively, and then inoculated in MM added of glucose (6 g l-1 or 1 g l-1), lindane (10 mg l-1) and glucose plus lindane respectively. The growth was determine as dry weight (g l-1), the residual lindane was measured by gas chromatography and the residual glucose by an enzymatic method. When M7 was previously adapted in glucose and inoculated in MM added of glucose 6 g l-1 and lindane, this strain removed both compounds until 24 h of incubation and 70% lindane at 96 h of incubation. When the strain was previously adapted in lindane, it was observed a removal of 80% lindane at 48 h and 100% at 96 h of incubation. In presence of glucose 1 g l-1 and lindane, previously adapted in glucose and lindane, the removal of the pesticide was only 45% at 96 h of incubation. These results indicate that high glucose concentration has a positive influence in the capacity of lindane removal by the streptomycete M7. This strain could have a great potential in bioremediation of lindane.