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Profiling of microbial communities in environmental samples often utilizes phospholipid fatty acid (PLFA) analysis. This method has been used for more than 35 years and is still popular as a means to characterize microbial communities in a diverse range of environmental matrices. This review examines the various recent applications of PLFA analysis in environmental studies with specific reference to the interpretation of the PLFA results. It is evident that interpretations of PLFA results do not always correlate between different investigations. These discrepancies in interpretation and their subsequent applications to environmental studies are discussed. However, in spite of limitations to the manner in which PLFA data are applied, the approach remains one with great potential for improving our understanding of the relationship between microbial populations and the environment. This review highlights the caveats and provides suggestions towards the practicable application of PLFA data interpretation., (© 2015 The Society for Applied Microbiology.)

Environmental pressure from mining activities such as those from the platinum sector occurs through the fine-grounded slurry from the processing plants, with its associated extracting chemicals that reach the tailings disposal facility (TDF). It is important that the effects of these activities on the environment are examined, especially in South Africa where there is a general paucity on data pertaining to pollution from platinum mining. The aim of this study was to do a preliminary assessment of the possible effects of platinum TDFs on the surrounding soil environment from a microbial perspective that might be used as a possible indicator in future environmental assessment studies. This was achieved by using enzymatic analyses (β-glucosidase, urease, phosphatase and dehydrogenase activity) and signature lipid biomarkers. From a soil physical perspective there was a significant difference between the soil at the TDF site in comparison to the sites situated further along (increasing distances away from TDF) the area investigated. Chemically the soil on the TDF had higher C, N, NH4 and K levels in comparison to the other sampling sites as well as higher Cu and Ni levels. Results from the enzymatic activities indicated a decrease in activity further away from the TDF although the sampling site the furthest away from the TDF had the highest viable biomass as indicated by the phospholipid fatty acids (PLFA’s). [ABSTRACT FROM AUTHOR]

Bioremediation has become an important method for the treatment of terrestrial oil spills and is often favoured over strictly physical-chemical methods. In this study, enzymatic analyses and signature lipid biomarkers were employed to evaluate the efficacy of selected bioremediation products on control and oil contaminated soil plots. It is envisioned that these biological indicators may be used as possible adjuncts to the strictly physical-chemical criteria most commonly employed. The application of the enzymatic and signature biomarker methods for product evaluation proved successful. The enzymatic assays provided a valuable insight into shifts in the functional diversity of the soil microbial communities resultant from the various treatments. Stimulation or inhibition of the microbial communities as a result of the various treatments was also demonstrated, particularly with regards to dehydrogenase activity. Phospholipid fatty acid profiles proved sufficiently sensitive to allow differentiation between products and resultant microbial communities that corresponded to satisfactory and unsatisfactory petroleum hydrocarbon removal. [ABSTRACT FROM AUTHOR]