RESUMO
ObjectiveTo establish the identification method of Dalbergiae Odoriferae Lignum（DOL） and its counterfeits by nuclear magnetic resonance hydrogen spectrum（1H-NMR） combined with multivariate statistical analysis. Method1H-NMR spectra of DOL and its counterfeits were obtained by NMR， and the full composition information was established and transformed into a data matrix， and the detection conditions were as follows：taking dimethyl sulfoxide-d6（DMSO-d6） containing 0.03% tetramethylsilane（TMS） as the solvent， the constant temperature at 298 K（1 K=-272.15 ℃）， pulse interval of 1.00 s， spectrum width of 12 019.23 Hz， the scanning number of 16 times， and the sampling time of 1.08 s. Similarity examination and hierarchical cluster analysis（HCA） were performed on the data matrix of DOL and its counterfeits， and orthogonal partial least squares-discriminant analysis（OPLS-DA） was used to analyze the data matrix and identify the differential components between them. In the established OPLS-DA category variable value model， the category variable value of DOL was set as 1， and the category variable value of the counterfeits was set as 0， and the threshold was set as ±0.3， in order to identify the commercially available DOL. The OPLS-DA score plot was used to determine the types of counterfeits in commercially available DOL， and it was verified by thin layer chromatography（TLC）. ResultThe results of similarity analysis and HCA showed that there was a significant difference between DOL and its counterfeits. OPLS-DA found that the differential component between DOL and its counterfeits was trans-nerolidol. The established category variable value model could successfully identify the authenticity of the commercially available DOL. The results of the OPLS-DA score plot showed that there were heartwood of Dalbergia pinnata and D. cochinchinensis in the commercially available DOL， and were consistent with the TLC verification results. ConclusionThere is a phenomenon that heartwood of D. pinnata and D. cochinchinensis are sold as DOL in the market. 1H-NMR combined with multivariate statistical analysis can effectively distinguish DOL and its counterfeits， which can provide a reference for the identification of them.
