Agilent 7890b gc ms system

The skin samples from the EU+UVB group (n = 3) were treated with 10 mL of acetonitrile through sonication, followed by centrifugation. The subsequent residues were subjected to additional extraction with 5 mL of acetonitrile, followed by sonication and centrifugation. The supernatants were pooled and degreased by adding 5 mL of acetonitrile-saturated n-hexane. The acetonitrile layer was retrieved after centrifugation and desiccated in a 45 °C water bath using nitrogen gas. The residues were reconstituted in 500 μL of ethyl acetate for gas chromatography-mass spectrometry (GC-MS). The prepared samples were injected into an Agilent 7890B GC-MS system (Agilent, Santa Clara, CA, USA), using a 2 × 15 m × 0.25 mm × 0.25 μm HP-5MS column for separation.

LrSRRPs were treated with methanolic HCl (1 M) for 16 h and 5 μg of myo-inositol added as internal standard. Silver carbonate (~50 mg) was added to the solution, followed by 100 μL acetic anhydride and the reactions were incubated at room temperature for 16 h in the dark. Lipids were removed by three washes with heptane and the remaining methanolic phase was dried under a gentle nitrogen flow. Tri-Sil HTP reagent (200 μL) (ThermoFischer Scientific, Loughborough, UK) was added to the dried sample and the reaction was incubated at 80°C for 30 min. The solution was dried under nitrogen and 1 mL of hexane was used to extract sugars by sonication for 15 min. The samples were transferred to clean vials, dried and dissolved in dichloromethane (100 μL) before injection onto the GC–MS. The samples were analyzed on an Agilent 7890B GC–MS system paired with an Agilent 5977 A mass spectrometry detector (Agilent, UK), using a BPX70 column (SGE Analytical Science, Australia). Helium was used as the carrier gas. The inlet was maintained at 220°C, 12.9 psi, and 23 mL/min flow. The injection volume was 1 μL in split mode (1:20). The oven temperature increased initially from 100°C to 120°C over 5 min, followed by a second increase from 120°C to 230°C over 40 min.