TRANSFORMATION OF ANILINE TO CATECHOL BY SEDIMENTARY EXTREME HALOPHILES IN VITRO

摘要

Aniline is a major contaminant originating from pesticides, manufacture of dye and agrochemicals; it undergoes complex environmental transformations, which are mediated by both biotic and abiotic factors. Goa, on the West Coast of India is a rapidly expanding urban tourist and industrial center and lies in the proximity of oil tanker routes; there have been several oil tanker spills and accidents in this region, which have often resulted in tar balls persisting in the estuarine network and (hypersaline) salt pans of this region. Eubacterial and extreme halophiles including those classified under Archaea represent a unique class of microorganisms in terms of their biochemical properties as well as their ecological distribution. In order to understand their possible role in transformation/bioremediation of a common organic contaminant like aniline, several archaeal halophiles isolated from the estuarine and continental shelf sediments of/off Goa were studied in vitro. Aniline was used as sole source(s) of carbon and nitrogen, in synthetic media (containing 20% NaCl). Catechol as a transformation product was detected/measured using the Arnow test. Catechol formation could be detected only when aniline was used as sole source of nitrogen. The results are indicative of the possible role of sedimentary halophilic archaea in bioremediation/transformation and fate of a pollutant like aniline in hypersaline conditions like saltmarsh ecosystems.