title: Supercritical fluid extraction of bacterial and archaeal lipid biomarkers from anaerobically digested sludge.
abstract: Supercritical fluid extraction (SFE) was used in the analysis of bacterial respiratory quinone (RQ), bacterial phospholipid fatty acid (PLFA), and archaeal phospholipid ether lipid (PLEL) from anaerobically digested sludge. Bacterial RQ were determined using ultra performance liquid chromatography (UPLC). Determination of bacterial PLFA and archaeal PLEL was simultaneously performed using gas chromatography-mass spectrometry (GC-MS). The effects of pressure, temperature, and modifier concentration on the total amounts of RQ, PLFA, and PLEL were investigated by 23 experiments with five settings chosen for each variable. The optimal extraction conditions that were obtained through a multiple-response optimization included a pressure of 23.6 MPa, temperature of 77.6 °C, and 10.6% (v/v) of methanol as the modifier. Thirty nine components of microbial lipid biomarkers were identified in the anaerobically digested sludge. Overall, the SFE method proved to be more effective, rapid, and quantitative for simultaneously extracting bacterial and archaeal lipid biomarkers, compared to conventional organic solvent extraction. This work shows the potential application of SFE as a routine method for the comprehensive analysis of microbial community structures in environmental assessments using the lipid biomarkers profile.
authors.affiliation: Department of Environmental and Life Sciences, Toyohashi University of Technology, Aichi 441-8580, Japan.|Center for Energy Resources Development, Agency for the Assessment and Application of Technology, Jakarta 10340, Indonesia.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Hanif
authors.affiliation: Department of Environmental and Life Sciences, Toyohashi University of Technology, Aichi 441-8580, Japan.
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Atsuta
authors.affiliation: Graduate School of Environment and Information Sciences, Yokohama National University, Kanagawa 240-8501, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Fujie
authors.affiliation: Department of Environmental and Life Sciences, Toyohashi University of Technology, Aichi 441-8580, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Daimon
mesh_terms: D000693:Anaerobiosis; D001105:Archaea / Q000737:chemistry* / Q000302:isolation & purification; D001419:Bacteria / Q000737:chemistry* / Q000302:isolation & purification; D015415:Biomarkers / Q000032:analysis; D025924:Chromatography, Supercritical Fluid / Q000379:methods; D005227:Fatty Acids / Q000032:analysis; D008055:Lipids / Q000032:analysis / Q000302:isolation & purification*; D010742:Phospholipid Ethers / Q000032:analysis; D010743:Phospholipids / Q000032:analysis; D011809:Quinones / Q000032:analysis; D012722:Sewage / Q000737:chemistry* / Q000382:microbiology*
chemical_list: D015415:Biomarkers; D005227:Fatty Acids; D008055:Lipids; D010742:Phospholipid Ethers; D010743:Phospholipids; D011809:Quinones; D012722:Sewage