Figure 7.

(A) Overlay of NMR spectra analyses of NIST SRM 3247 Ginkgo (G. biloba L.) extract (black trace) vs. a product obtained from the market purported to be Ginkgo extract (green line). Differences in peak frequencies and intensities were noted in the aromatic and aliphatic regions (6–8 and 1–3 ppm, respectively); green asterisks indicate rutin peaks. (B) Dendrogram analysis of the hierarchical clustering resulting from unsupervised analyses of NMR spectra of various Ginkgo products. Non-targeted NMR profiling of Ginkgo extracts (GbE) was conducted on NTP test articles (1, 1A, 1F), products procured from the U.S. market claimed as containing Ginkgo (A-T), NIST SRM 3247 Ginkgo extract (U), and NIST SRM 3248 Ginkgo SODF (V). Samples with spectra characteristic of Ginkgo clustered together (red), including NIST SRMs (black box), while samples with very low levels of flavonols and terpene trilactones were clustered separately (green and blue). Adapted with permission from Collins et al. (116), under Creative Commons license (https://creativecommons.org/licenses/by/4.0/legalcode).