The aim of this study concerns the use of locally isolated microorganisms in bioremediation the
polluted soil with pesticides. Therefore, the study included isolation and identification of some
microorganisms from treated soil increasingly by carbofuran and tested for their tolerance and ability to
degrade carbofuran which is extensively used under Egyptian Agricultures against many pests. Obtained
results could be summarized as follows:
Only two kinds of the isolated microorganisms were able to grow and withstand the toxicity of
carbofuran. These microorganisms were identified as Streptomyces violaceusniger and Azospirillum
brasilense. Results also indicated that carbofuran dissipation rate in culture of A.brasilense was faster
than that in S.violaceusniger one, since only 7.5 and l0.5% of the applied carbofuran were detected by
GLC in the culture of A.brasilense and S.violaceusniger, respectively at the end of experiment (21 days).
S.violaceusniger was more efficient in biodegradation of carbofuran than A.brasilense since, six
metabolites were detectedin S.violaceusniger culture by GLC and TLC, three of them were identified as
carbofuran phenol,3-hydroxy carbofuran and 3-keto carbofuran, whereas the other three metabolites
could not be identified. A.brasilense degraded carbofuran to only three metabolites, two of them were
identified as carbofuran phenol and 3-keto carbofuran, while the third one could not be identified.
Moreover, carbofuran dissipation rate in cultivated soil with tomato and treated with carbofuran was
higher in case of inoculation with the mixture of S.violaceusniger and A.brasilense than that inoculated
with each one individually. Therefore, soil inoculation with either S.violaceusniger, A.brasilense or a
mixture of them is almost important for biodegradation of carbofuran and removing its residues from
the polluted soil.
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