19091s 433 column

A gas chromatography-mass spectrometry (GC-MS) analysis was performed to identify secondary metabolites from the partially purified crude fungal extracts. GC-MS was performed in the chemistry department at the University of KwaZulu-Natal (PMB). Briefly, GC-MS analysis was performed by splitless injection (spilt 20:80-8-200-5M-8-260-10M10-280-HP5-ETOH) of 1.0 µL of the sample in methanol on a Hewlett Packard 6890 (USA) gas chromatograph. The Agilent 19091S-433 column (30 m × 250 μm × 0.25 µm) was used to separate the samples. The starting column temperature was 35 °C with a hold time of 3 min. The temperature was set to increase at 8 °C/min, with a maximum temperature of 280 °C. One microliter of the sample was injected into the port, subsequently vaporized, and transported down the column utilizing helium as the carrier gas at a flow rate of 1 mL/min. At 70 eV, the MS spectrum was captured. Following the separation in the column, the components were identified and evaluated using a flame ionization detector (FID). Compounds were identified by comparing the spectrum of unknown compounds to the spectrum of known compounds in the National Institute of Standards and Technology (NIST MS 2.0) structural library to determine their names, molecular weight, and structure [46 (link)].

Lipid samples were silylated for GC analysis [68 (link)], and a 1-µL aliquot was injected into an Agilent Technologies Model 6890 Gas Chromatograph equipped with an Agilent 19091S-433 column (30.0 m × 250 µm × 0.25 µm). MS-analysis was conducted by coupling the column eluent to a Model 5973 Mass Selective Detector capable of electrical ionization (EI). The chromatography temperature program initially started at 50 °C for 1 min, then raised at a rate of 25 °C per min to 200 °C, held at 200 °C for 2 min, and again raised at a rate of 10 °C per min to 280 °C and maintained at that temperature for 2 min, then raised at 20 °C per min to 320 °C, where it was maintained for 20 min.