Wild-Simulated Gastrodia elata Bl.: Quality Assessment by High Performance Liquid Chromatography Fingerprinting and Antioxidant and Neuroprotective Activities

High performance liquid chromatography (HPLC) fingerprints and multi-component determination methods were established to investigate the differences in quality among the dried tubers of wild-simulated Gastrodia elata Bl. (Rhizoma Gastrodiae) from different geographical origins by combining fingerprint similarity evaluation, principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA). By comparative analysis of the fingerprints of 15 batches of Rhizoma Gastrodiae samples from major production regions in Guizhou province, a total of 14 shared peaks were identified and assigned to 6 signature components, including gastrodin, p-hydroxybenzyl alcohol, parishin E, parishin B, parishin C and parishin A. PCA showed that the first three principal components cumulatively explained 83.373% of the variance, and gastrodin and parishin A were selected as markers to discriminate between different categories of Rhizoma Gastrodiae. OPLS-DA ascertained that gastrodin, p-hydroxybenzyl alcohol, parishin C, parishin B, and parishin A affected the quality of Rhizoma Gastrodiae. The total content of signature components of Rhizoma Gastrodiae was 12.957–36.738 mg/g, and parishin A accounted for the largest proportion of it. Under the same limiting condition, significant differences in the contents of signature components were observed between wild-simulated and bag-cultivated Rhizoma Gastrodiae. The antioxidant capacity and neuroprotective activity of Rhizoma Gastrodiae were investigated by kits and in vitro cellular experiments, revealing that the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cationic radical and hydroxyl radical scavenging capacity and neuroprotective activities of wild-simulated Rhizoma Gastrodiae on PC12 and HT-22 neurons were superior to those of bag-cultivated Rhizoma Gastrodiae. This study provides data support for the establishment of quality standards for wild-simulated Rhizoma Gastrodiae.