Gc ms 7000d

Chemotaxonomic markers of the strains and their close phylogenomic neighbors were determined using standard thin-layer chromatographic procedures. To this end, isomers of diaminopimelic acid (A2pm) (Schleifer and Kandler, 1972 (link)) and polar lipid (Bligh and Dyer, 1959 (link); Tindall et al., 2007 (link)) patterns were carried out. Cellular fatty acids of the strains were extracted and analyzed by gas chromatography (Agilent 6890N) following the standard protocols of the microbial identification (MIDI) system (Sasser, 1990 ). Fatty acids were identified by a GC–MS run on an Agilent GC–MS 7000D instrument (Vieira et al., 2021 (link)). Isoprenoid quinones were extracted, separated by HPLC, and identified by using both a DAD and high-resolution mass spectrometer, according to the work of Schumann et al. (2021) (link). Biochemical and enzymatic properties of the strains and their phylogenomic neighbors were determined using API-ZYM and API 20NE strips, as instructed by the manufacturer (bioMerieux, Lyon, France).

The tissue sample was precisely weighed 50 mg, added into 1 mL of 6% phosphoric acid solution homogenate, and then transferred to a 20 mL headspace sample bottle. GC–MS 7000D (Agilent Technologies) was used to measure the changes of short‐chain fatty acids in the colon of mice for each intervention group. Static headspace injection was used with an incubation temperature of 85°C, incubation time of 30 min, injection needle temperature of 95°C, and injection volume of 1 mL. The selective ion monitoring mode was adopted. The mass‐to‐charge ratio of acetic acid, propionic acid, isobutyric acid, butyric acid, and valeric acid were 60, 74, 743, 60, 60 respectively. The collected peak area ratio of each peak was substituted into the standard curve to calculate the content of each component in the sample.