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The age of the ginseng plant has been considered as an important criterion to determine the quality of this species. For age differentiation and structure interpretation of age-dependent key constituents of Panax ginseng, hairy root (fine root) extracts aged from four to six years were analyzed using a nontargeted approach with ultraperformance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-QTOFMS). Various classification methods were used to determine an optimal method to best describe ginseng age by selecting influential metabolites of different ages. Through the metabolite selection process, several age-dependent key constituents having the potential to be biomarkers were determined, and their structures were identified according to tandem mass spectrometry and accurate mass spectrometry by comparing them with an in-house ginsenoside library and with literature data. This proposed method applied to the hairy roots of P. ginseng showed an improved efficiency of age differentiation when compared to previous results on the main roots and increases the possibility of the identification of key metabolites that can be used as biomarker candidates for quality assurance in ginseng.

Two new polyhydroxylated macrolides, seimatopolides A (1) and B (2), were isolated from an EtOAc extract of Seimatosporium discosioides culture medium. The structures of the new compounds were established on the basis of spectroscopic analysis, including 1D and 2D NMR, and their absolute configurations were determined using the modified Mosher's method. Seimatopolides A (1) and B (2) activated peroxisome proliferator-activated receptor (PPAR)-γ with EC(50) values of 1.15 and 11.05 μM, respectively. The expression of PPAR-γ target genes in HepG2 hepatocytes was significantly altered; in particular, expression of the gluconeogenic genes glucose-6-phosphatase (G6Pase) and phosphoenolpyruvate carboxykinase (PEPCK) was reduced upon stimulation with 1, supporting the proposal that compound 1 is both a PPAR-γ agonist and a possible therapeutic candidate for treatment of diabetes.

Five new dimeric ent-kauranoids, biexcisusins A–E (1–5), were isolated from the aerial parts of Isodon excisus. The structures and relative configurations of these compounds were determined on the basis of spectroscopic data interpretation. Of these, biexcisusins C–E (3–5) are dimeric ent-kaurane diterpenoids exhibiting an unprecedented linkage through a nine-membered lactone ring between two ent-kaurane subunits. Compounds 1–5 showed no inhibitory effects on the LPS-induced production of nitric oxide in murine macrophage RAW264.7 cells, up to a dose of 50 μM.