Phenyl methyl silox

Samples were analyzed on an Agilent 7890A/5975C GC-MS system (Agilent Technologies Inc., CA, USA) employing a HP-5 MS capillary column coated with 5% phenyl methyl silox (Agilent J & W Scientific, Folsom, CA, USA). The obtained GC/MS raw data in [D] format were converted to mzXML format using msConvert (ProteoWizard tool) and subsequently preprocessed, cleaned, deconvoluted and aligned using the Automated Mass Spectral Deconvolution and Identification System (AMDIS, National Institute of Standards and Technology, USA) interface to match against the freely available Mass Spectral (MS) and Retention Time Index (RI) (MSRI) library at the Golm Metabolome Database. Metabolites were then identified by comparison to the National Institute of Standards and Technology Mass Spectral Reference Library 2011 (NIST11/2011; National Institute of Standards and Technology, USA). Following log transformation and imputation with minimum observed values for each compound, the data were analyzed using one-way analysis of variance (ANOVA).

Samples were analyzed with an Agilent Gas Chromatography Mass Spectrometer (7890A/5975C GC-MS System, Agilent, CA, USA). The GC system employed a HP-5MS capillary column coated with 5% phenyl methyl silox (Agilent J & W Scientific, Folsom, CA, USA). Samples (1 μL) were injected at a split ratio of 20:1. As a carrier gas, helium was set to a constant flow rate of 1.0 mL/min. The temperatures were set to 280°C (injection), 250°C (transfer line) and 150°C (ion source), respectively. The initial temperature program was set at 2 min of isothermal heating at 70°C and then increased to 300°C at a rate of 10°C/min. The final temperature was maintained for 5 min. Electron impact ionization (70 eV) in a full scan mode with an m/z range of 35-780 was used for data acquisition.