Bacterial production of hydroxylated and amidated metabolites of flurbiprofen

Review on fate and mechanism of removal of pharmaceutical pollutants from wastewater using biological approach

Due to research advancement and discoveries in the field of medical science, maintains and provides better human health and safer life, which lead to high demand for production of pharmaceutical compounds with a concomitant increase in population. These pharmaceutical (biologically active) compounds were not fully metabolized by the body and excreted out in wastewater. This micro-pollutant remains unchanged during wastewater treatment plant operation and enters into the receiving environment via the discharge of treated water. Persistence of pharmaceutical compounds in both surface and ground waters becomes a major concern due to their potential eco-toxicity. Pharmaceuticals (emerging micro-pollutants) deteriorate the water quality and impart a toxic effect on living organisms. Therefore, from last two decades, plenty of studies were conducted on the occurrence, impact, and removal of pharmaceutical residues from the environment. This review provides an overview on the fate and removal of pharmaceutical compounds via biological treatment process.

Microbial degradation of fluorinated drugs: biochemical pathways, impacts on the environment and potential applications

Since the discovery over 60 years ago of fluorocortisone's biological properties (9-α-Fluoro derivatives of cortisone and hydrocortisone; Fried J and Sabo EF, J Am Chem Soc 76: 1455-1456, 1954), the number of fluorinated drugs has steadily increased. With the improvement in synthetic methodologies, this trend is likely to continue and will lead to the introduction of new fluorinated substituents into pharmaceutical compounds. Although the biotransformation of organofluorine compounds by microorganisms has been well studied, specific investigations on fluorinated drugs are relatively few, despite the increase in the number and variety of fluorinated drugs that are available. The strength of the carbon-fluorine bond conveys stability to fluorinated drugs; thus, they are likely to be recalcitrant in the environment or may be partially metabolized to a more toxic metabolite. This review examines the research done on microbial biotransformation and biodegradation of fluorinated drugs and highlights the importance of understanding how microorganisms interact with this class of compound from environmental, clinical and biotechnological perspectives.

A convenient chemical-microbial method for developing fluorinated pharmaceuticals

A significant proportion of pharmaceuticals are fluorinated and selecting the site of fluorine incorporation can be an important beneficial part a drug development process. Here we describe initial experiments aimed at the development of a general method of selecting optimum sites on pro-drug molecules for fluorination, so that metabolic stability may be improved. Several model biphenyl derivatives were transformed by the fungus Cunninghamella elegans and the bacterium Streptomyces griseus, both of which contain cytochromes P450 that mimic oxidation processes in vivo, so that the site of oxidation could be determined. Subsequently, fluorinated biphenyl derivatives were synthesised using appropriate Suzuki-Miyaura coupling reactions, positioning the fluorine atom at the pre-determined site of microbial oxidation; the fluorinated biphenyl derivatives were incubated with the microorganisms and the degree of oxidation assessed. Biphenyl-4-carboxylic acid was transformed completely to 4'-hydroxybiphenyl-4-carboxylic acid by C. elegans but, in contrast, the 4'-fluoro-analogue remained untransformed exemplifying the microbial oxidation - chemical fluorination concept. 2'-Fluoro- and 3'-fluoro-biphenyl-4-carboxylic acid were also transformed, but more slowly than the non-fluorinated biphenyl carboxylic acid derivative. Thus, it is possible to design compounds in an iterative fashion with a longer metabolic half-life by identifying the sites that are most easily oxidised by in vitro methods and subsequent fluorination without recourse to extensive animal studies.

The microbial cell factory

Microorganisms have been used for decades as sources of antibiotics, vitamins and enzymes and for the production of fermented foods and chemicals. In the 21st century microorganisms will play a vital role in addressing some of the problems faced by mankind. In this article three of the current applications in which microbes have a significant role to play are highlighted: the discovery of new antibiotics, manufacture of biofuels and bioplastics, and production of fine chemicals via biotransformation.