ABSTRACT

Department of Microbiology, Abeda Inamdar Senior College, 2390-KB Hidayatullah Road, Azam Campus, Camp, Pune 411001, Maharashtra, India

14.1 INTRODUCTION

14.1.1 WHAT ARE XENOBIOTICS?

Xenobiotics (Greek – Xenos: Strange, foreign, foreigner) are chemically synthesized compounds that are not found in nature and are therefore branded as “Foreign to Biosphere”. Microorganisms have not been exposed to such ‘strange’ structures during evolution. This leads to resistance to biodegradation of xenobiotics by microorganisms. These foreign compounds with unnatural structures are mostly toxic and are indeed harmful to life in general. Some of the core anthropogenic compounds (pollutants) present in the environment are petroleum hydrocarbons, halogenated solvents, endocrine disrupting drugs, explosives, agricultural chemicals, heavy metals, metalloids, and radionuclides. Pollutants with xenobiotic structural features like polycyclic aromatic hydrocarbons, halogenated aliphatic and aromatic hydrocarbons, nitroaromatic compounds, azo compounds, s-triazins, organic sulphonic acids, and synthetic polymers are also recalcitrant in the environment.