2.2. Characterization of Phycocompounds by GCMS Analysis

The extraction was carried out by using 500 g of dry powder in ethanol (80%) at 70 °C by continuous hot percolation using the Soxhlet apparatus. It was continued for 24 h, and the ethanolic extract was then filtered and kept in a hot air oven (RDHO 80, Dry hot air oven, REMI, Bengaluru, India) at 40 °C for 24 h to evaporate the ethanol (Sigma-Aldrich, Bengaluru, India) from it. The extract obtained was concentrated to dryness under decreased pressure (150 mbar) at 20 °C using a rotary vacuum evaporator (Sigma Scientific, Nanganallur, Chennai, India). The obtained residue was kept separately in airtight containers and stored in a deep freezer (−20 °C, Esquire Biotech, Chennai, India).

For GC-MS analysis, the sample was injected into an EB-5 column in the JMS-T100GCV GC model used for chromatographic separation. Helium was used as carrier gas with a flow rate of 1 mL/min; the injector was operated at 200 °C and column oven temperature was programmed as 50–250 °C at a rate of 10 °C/min injection mode. The following MS conditions were used: For mass spectrometry analysis, AccuTof Mass from jeol was used. ionization voltage of 70 eV; ion source temperature of 250 °C; interface temperature of 250 °C; the mass range of 50–600 mass units. A gas chromatogram was obtained and the mass spectrum of the unknown phycocompounds was compared with the spectrum of the known components stored in the NIST library version 2005.