Utilization and degradation of lindane by soil microorganisms

Area of Science:

• Environmental microbiology
• Bioremediation
• Pesticide degradation

Background:

• Lindane (gamma-1,2,3,4,5,6-hexachlorocyclohexane) is a persistent organochlorine pesticide.
• Soil microorganisms play a crucial role in the environmental fate of pesticides.
• Understanding microbial metabolism of lindane is vital for developing remediation strategies.

Purpose of the Study:

• To identify soil microorganisms capable of growing on and degrading lindane.
• To investigate the metabolic pathways of lindane utilization by selected microbes.
• To assess the potential of specific bacterial strains for lindane bioremediation.

Main Methods:

• Isolation and screening of microorganisms from loamy sand for lindane utilization.
• Cultivation of selected microbes in aqueous media with lindane as a sole carbon source.
• Identification of lindane metabolites using chromatographic techniques.
• Assessing bacterial adaptation and degradation of lindane and its metabolites via oxygen consumption measurements.

Main Results:

• 71 out of 147 soil isolates showed good growth on lindane and produced chloride.
• Thirteen soil microorganisms were selected for further study.
• Lindane was metabolized into several intermediates, including gamma-PCCH, alpha-TCCH, beta-TCCH, gamma-TCCH, and PCB.
• Pseudomonas sp. No. 62 adapted to and degraded lindane and its metabolites, including various tetrachlorobenzenes.

Conclusions:

• Soil microorganisms possess the capability to metabolize lindane into various chlorinated compounds.
• Specific bacterial strains, such as Pseudomonas sp. No. 62, can degrade lindane and its transformation products.
• These findings highlight the potential of microbial communities for the bioremediation of lindane-contaminated environments.