Qp5050a system

The analysis of the chemical composition of the essential oil was performed at the Federal University of Piauí, using a gas chromatography coupled to mass spectrometer (GC/MS) in a Shimadzu instrument with mass selective detector QP5050A system, operating at 70 eV of ionization energy. Capillary column Agilent DB-5HT was used (30 m × 0.25 mm of internal diameter) with the following specifications: gun temperature of 270 °C and detector temperature of 290 °C, using helium gas as carrier gas (1.0 mL/min); linear speed of 47.3 cm/sec; total flux of 24 mL/min; carrier flux of 24 mL/min; pressure of 107.8 kPa; the heating temperature of the column was set to 60 °C (2 min) to 180 °C (1 min) at 4 °C/min and 180-260 °C at 10 °C/min (10 min). The identification of the compounds was carried out by comparisons between the respective mass spectrometer and patterns registered in the Wiley 229 database and between the retention index calculations and specialized literature values (Adams 2001 ).

GC-MS was performed on a QP5050A system (Shimadzu Corp., Kyoto, Japan) using an Equity-5 column (0.25 mm i.d. × 30 m, 0.25 μm film thickness; Supelco, Inc., Bellefonte, PA, USA). The HPLC consisted of a 626 pump with 996 photodiode array detector (Waters Corp., Milford, MA) equipped with a C-18 column (Inertsil ODS-3, 5 μm, 250 × 4.6 mm ID; GL Sciences, Inc., Tokyo, Japan). ¹H and ¹³C NMR spectra were recorded with tetramethylsilane as the internal standard using JNM-EX270 (270 MHz) and JNM-LA500 (500 MHz) NMR spectrometers (JEOL Ltd., Tokyo, Japan). High resolution mass spectra were obtained with a JMS-T100LC AccuTOF mass spectrometer (JEOL). The seeds used in the present study have been previously described6 (link). They were planted at a depth of 5 mm in pots (8 × 8 × 6 cm deep) containing sand and then incubated in an illuminated growth chamber (FLI-301N; Tokyo, Rikakikai, Co., Ltd., Tokyo, Japan) under a 16-h light/8-h dark cycle at 22 °C.