Advances in microbial bioremediation and the factors influencing the process

Abstract

Irrational and rapid global human societal development has culminated to a condition of environmental deterioration. Accidental leakage and deliberate use of organic and inorganic chemicals have contaminated the environment up to the level of ecosystem. Advancements have been made in the field of research on bioremediation of the hazardous contaminants especially in last three decades. Microbial bioremediation has been the most understood biotechnological process of environmental restoration. Bacteria and fungi because of their inherent ability to adapt and grow in extreme environments have been employed for either removal or degradation of the chemical contaminants. Researchers all over the world are getting breakthroughs in finding new bacterial strains having plasmid linked degradation/ reduction ability. Molecular biology and genetic engineering helped in crafting the microbes for the desired results on environment. Despite having favorable conditions, microbial remediation largely depends on environmental factors and on the basic biological characters of microbes, especially bacteria being Grampositive or Gram-negative. Metagenomic studies revealed the importance of microbial ecology as microbes work well in community, i.e., consortia. This review along with several other studies suggests the need of precision during microbial community identification, substrate specificity and the designing of microbes.

Plant–microbe interaction in aquatic system and their role in the management of water quality: a review

“…Moreover, molecular techniques such as denaturing gradient gel electrophoresis (DGGE) and terminal restriction fragment length polymorphism (TRFLP) fingerprints of PCR amplified 16S rDNA fragments can easily provide the information of overall pattern of microbial community of biofilm (Truu et al 2009). Metagenomics studies revealed that microbes perform well in the community, i.e., consortia (Srivastava et al 2014). In general, microbial communities in a biofilm provide plenty of opportunities to bacterial cells for exchange of genetic information through horizontal gene transfer (HGT) conferring resistance, tolerance and chemical degrading ability (Srivastava et al 2014).…”

“…Metagenomics studies revealed that microbes perform well in the community, i.e., consortia (Srivastava et al 2014). In general, microbial communities in a biofilm provide plenty of opportunities to bacterial cells for exchange of genetic information through horizontal gene transfer (HGT) conferring resistance, tolerance and chemical degrading ability (Srivastava et al 2014). Moreover, HGT is often held responsible for enhancing the competitiveness of bacteria in the natural environments (Ventura et al 2007).…”

“…Massive field application of organic compounds such as poly-aromatic hydrocarbons (PAHs), chlorinated organic compounds, poly-brominated biphenyls ethers (PBEs) and poly-chlorinated biphenyls (PCBs) have been a major cause of contaminated environmental media (Srivastava et al 2014) and the aquatic systems are the most vulnerable of all. Because of the catabolic activity, microbes are well-known bioremediators able to degrade virtually all classes of organic chemicals (Hiraishi 2008;Fennell et al 2011).…”

“…Voluminous research literature is available addressing the issues of aquatic pollution (Nagai et al 2007;Camargo and Alonso 2006;Khan and Srivastava 2008;Shukla et al 2009) and its biological remediation (Sooknah and Wilkie 2004;Nahlik and Mitsch 2006;Hadad et al 2006;Srivastava et al 2014) and the references therein. Furthermore, earlier scientific researches apparently indicate that most of the water quality improvement studies have been carried on the environmental pollutants and their removal either by aquatic plants (in situ and ex situ) or by microbes alone and only few reports are available indicating direct impact of the interaction of the aquatic macrophytes and microbes (Stout and Nüsslein 2010;Sharma et al 2013;Lamers et al 2012;Lu et al 2014) and its possible influence on water quality (Stottmeister et al 2003;Radhika and Rodrigues 2007;Srivastava et al 2007;Toyama et al 2011;Chakraborty et al 2013).…”

Plant-bacteria synergism: An innovative approach for the remediation of crude oil-contaminated soils

“…Despite the fact that hydrocarbon biodegradation can occur over an extensive range of temperatures, the rate of biodegradation usually declines with the diminishing temperature. It also has a major effect on microbial metabolism and consequently on microbial activity in the environment (Srivastava et al, 2014).…”