Seasonal variations in sugar contents and microbial community in a ryegrass soil

Effects of short-term ecosystem experimental warming on water-extractable organic matter in an ombrotrophic Sphagnum peatland (Le Forbonnet, France)

“…Similarly, mannitol as well as the non-reducing disaccharide trehalose are considered as osmolytes that can accumulate in microbial and plant cells in response to osmotic stress such as reduction in moisture or increase in temperature (Bohnert et al, 1995;Chaturvedi et al, 1997;Waisley, 2004, Medeiros et al, 2006. Under OTCs of the DRY site, mannitol had lower concentration in the rooting zone (2.5-7.5 cm depth) and this could indicate a decrease in osmotic stress.…”

“…Within such pools, the most labile OM has mainly been studied through the analysis of sugars which are considered as readily degradable constituents used preferentially by microorganisms (Haider, 1992;Volk et al, 1997). In investigating sugar composition and its link to microbial activity, Medeiros et al (2006) showed that some sugars such as mannitol, a polyol or reduced sugar, can also be seen as indicator of osmotic stress. On the other hand, the less labile OM of the WEOM is often investigated by way of specific ultra-violet absorbance at 280 nm (SUVA 280 ), which provides an estimate of aromaticity of the WEOM (Traina et al, 1990;Kalbitz et al 2003;Weishaar et al, 2003).…”

Effect of Sewage and Industrial Effluents on Bacterial and Archaeal Communities of Creek Sediments in the Taihu Basin

“…Previous studies of microbes in the environment have mainly been conducted using culture-based technique, but most microorganisms cannot be purified and separated in the laboratory, making it difficult to understand the differences in the microbial population structure under different habitats [1]. With the rapid development of molecular biotechnology, PLFA (phospholipid fatty acids), spectrogram analysis of phospholipid fatty acids [2,3], the Biolog method [4], polymerase chain reaction denaturing gradient gel electrophoresis(PCR-DGGE) [5,6], and high-throughput sequencing [7], have been widely applied to investigate microbial communities. Because of its high efficiency and accuracy, as well as its other characteristics [8], high-throughput sequencing has been widely used in the study of microbial communities in soil [9], freshwater ecosystems [10], and marine ecosystems [11].…”

Gas chromatography coupled to mass spectrometry for analyses of organic compounds and biomarkers as tracers for geological, environmental, and forensic research

“…Ergosterol is a primary fungal membrane sterol (C 28 ) and serves as a biomarker for determining fungal biomass in soil [e. g., 157] and aerosol [e. g., 158] samples. The disaccharide mycose is a known fungal metabolite [159,160] and has been detected in sediments [93], soils [161,162], and aerosols [e. g., 100,163,164]. Finally, usnic acid, which was detected in smoke samples from biomass burning [165], has been isolated from several species of lichen genera [166].…”

“…Ergosterol and trehalose (a.k.a. mycose) are also examples of microbial-derived compounds commonly used to study the fungal community in several soil samples [e. g., 157,161,259,260]. The use of GC -IRMS in soil science is significant and encompasses the investigation of origins (plant versus microbes) of homologous lipids (e. g., fatty acids, n-alkanes, n-alkanols) [261] and the fate and cycling of organic compounds by different microorganisms [e. g., 262] through the application of 13 C-labelled compounds (e. g., glucose), as well as the determination of individual turnover rates of specific lipid and non-lipid compounds (e. g., carbohydrates, lignin, lipids, and N-containing compounds) [263].…”