Abstract
A reversed phase-high performance liquid chromatography-diode array detector (RP-HPLC-DAD) method was developed to determine the amount of gastrodin, the major active component of Grammatophyllum speciosum pseudobulbs. A previous study suggested that the ethanolic extract of G. speciosum had a potential to encourage stemness of keratinocytes. Therefore, in order to determine the quality of G. speciosum ethanolic extract, the quantitative analysis of gastrodin should be validated. The optimized RP-HPLC condition was achieved within 18 min, using a column, Inertsil ODS-3 (4.6 x 150 mm, 5 µm). The mobile phase consisted of a mixture of water: acetonitrile with a gradient from 1:99 to 100:0 in 14 minutes and keep constant at 1:99 for 4 minutes. The flow rate was 1.7 mL/min with the monitored UV wavelength of 220 nm. Gastrodin was eluted at the retention time of 6.5 minutes. The calibration curve of gastrodin at the concentration of 10 - 100 µg/mL showed good linearity (r2 = 0.999). In addition, the intraday and interday precisions of gastrodin were 1.05 and 0.38%, respectively. The percentage recovery was within 99.3 - 101.5%. Average gastrodin contents in 3 samples were 55.52 - 58.12 mg/g. The results indicate that this method can be utilized to control the quality of G. speciosum extract.
… Gastrodin was found to elute at the retention time of 6.5 minutes. Gastrodin was identified by comparing the chromatogram and retention time of G. speciosum extract with gastrodin standard (% purity > 98%) (Chengdu Biopurify Phytochemicals, Sichuan, China) …
