The seeds were sown at 25 days intervals on 20th May, 15th June and 10th July, 2010 in the experimental plots with 60 × 30 cm spacing. All agronomical management practices were performed as needed. The samples click here of leaves and whole plants were collected at pre flowering and full flowering stages. Samples of whole plant, leaves, spikes and husk were subjected to hydro-distillation for 4 h using a Clevenger-type apparatus to produce oil. The oils were dried over anhydrous sodium sulphate and stored in sealed vial at low temperature before analysis. GC/MS analyzes were performed with a Perkin Elmer Clarus 500 gas chromatograph
equipped with a split/splitless injector (split ratio 50:1) data handling system. The column was Rtx®-5 capillary columns (60 m × 0.32 mm, 0.25 μm film thickness). Helium (He) was the carrier gas at a flow rate 1.0 ml/min. The GC was interfaced with (Perkin Elmer Clarus 500) mass detector operating in the EI+ mode. The mass spectra were generally recorded over 40–500 amu that revealed the total ion current (TIC) chromatograms. Temperature program was used as follows: initial temperature of 60 °C (hold: 2 min) programmed at a rate of 3 °C/min to a final temperature of 220 °C (hold: 5 min). The temperatures of the injector,
transfer line and ion source were maintained at 210 °C, 210 °C and 200 °C, respectively. The components of the oils were identified by comparison of their mass spectra with those selleck chemicals llc of commercial libraries (NIST/Pfleger/Wiley)
or with authentic compounds and confirmed by comparison of their retention indices either with those of authentic compounds or with data published in literature. 17 The average oil content in different plant parts were obtained as 0.06–0.10% (whole plant), 0.10–0.14% (leaves), 0.13–0.23% (spike) and 0.10–0.13% (husk) during different sowing times. The highest oil content obtained in all the spike samples at different sowing times, which ranged from 0.16 to 0.23% (D1), 0.15–0.20% (D2) and 0.13–0.18% (D3), whereas lowest oil yield obtained in whole plant, varied between 0.06 and 0.09% (D1), 0.06–0.10% (D2 and D3). Table 1 shows the identified constituents and their relative content in the essential oils obtained DNA ligase from whole plant, leaves, spikes and husk of Perilla frutescens at 3 sowing times, D1-seeds sown on 20th May, D2-seeds sown on 15th June and D3-seeds sown on 10th July. D1 stage: The major compound was found as perilla ketone (52.34–90.28%) followed by 1-methyl-2-methylene trans-decalin (4.49–32.98%). The percentage of perilla ketone, the first major compound in all the oils, was found maximum in spikes (90.28%) followed by husk (64.54%), leaves (54.56%) and whole plant (52.34%). 1-Methyl-2-methylene trans-decalin was higher in leaves oil (32.98%) and lower in spikes essential oil (4.49%). The amount of trans-caryophyllene was higher in the essential oil obtained from whole plant (8.54%) and also in husk (5.08%).