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92 PROCEEDINGS OF INTERNATIONAL SCIENTIFIC CONFERENCE ON APPLIED BIOTECHNOLOGY2.2. GC/FID-MS analysisWith the aid of the FID (flame ionization detection), the GC analysis of the obtained oil was completed using an Agilent Technologies GC HP7890A system with an HP-5MS column (5% phenyl, 95% dimethyl polysiloxane; 30m x 0.25mm, film thickness 0.25 %u00b5m) [8-10]. The oven temperature was increased by 5 oC/min from 40 to 250 oC, and then maintained isothermally at 250 oC for 10 min. The injector and detector were kept at 260 and 270 oC, respectively. Gas carrier He had a split of 1:9, and a flow rate of 1.0 mL/min.As with the GC-FID, the GC-MS analysis was carried out utilizing an Agilent Technologies 7890A GC linked with the MSD (mass spectrum detector) and an HP-5MS column. The ionization voltage was set at 70 eV, and the detector interface temperature was fixed at 280 oC. The acquisition mass was between 40 and 450 amu. The relative percentage of each component was calculated without correction using the GC peak area (the FID response). The retention indices (RIs) were calculated from gas chromatograms by using the logarithmic equation and the homologous series of n-alkanes (C-7 to C-30, USA) as standards. Each compound%u2019s name was determined by comparing its mass spectra and RIs to those in the Adams book and NIST Webbook [11, 12].2.3. Antimicrobial assaySeven microbacterial strains were used in this research, including three Gram-positive bacteria Enterococcus faecalis ATCC299212, Staphylococcus aureus ATCC25923, and Bacillus cereus ATCC14579, three Gram-negative bacteria Escherichia coliATCC 25922, Pseudomonas aeruginosa ATCC27853, and Salmonella enterica ATCC13076, and one yeast Candida albicans ATCC 10231. The method was described in our previous works, as provided in Supplementary Material [8-10].