| MS Description
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Equal amounts of cells (10 ml cell culture … Equal amounts of cells (10 ml cell culture with OD730 = 1.0) were harvested by rapid filtration using a previously described method (Osanai et al., 2014a). GC‐MS was carried out using a GCMS‐QP2010 Ultra equipped with a CP‐Sil 8 CB‐MS capillary column (30 m × 0.25 mm × 0.25 μm; Agilent, Palo Alto, CA, USA). Helium was used as the carrier gas. The flow rate was 2.1 ml min−1. The injection volume was 1 μl with a split ratio of 1:10. An initial oven temperature of 60°C was maintained for 10 min, then raised to 315°C at 15°C min−1, and maintained for 6 min. The total running time was 33 min. The other settings were as follows: 250°C interface temperature, 200°C ion source temperature and electron impact ionization at 70 eV. Organic acids were derivatized prior to analysis. The dried residue was derivatized for 90 min at 30°C in 20 μl 20 mg ml−1 methoxyamine hydrochloride in pyridine. Subsequently, trimethylsilylation (TMS derivatization) was performed for 30 min at 37°C and then for 2 h at room temperature with 50 μl N‐methyl‐N‐(trimethylsilyl)trifluoroacetamide (Roessner et al., 2000; Strelkov et al., 2004). sner et al., 2000; Strelkov et al., 2004).
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