Discovery of nontriterpenoids from the rot roots of Panax notoginseng with cytotoxicity and their molecular docking study and experimental validation.

Panax notoginseng (PN) is a well-known traditional Chinese medicine, with dammarane-type triterpenoid saponins characterized as major component and active ingredients, together with amino acids, flavonoids, polysaccharides, and polyacetylenes. The roots of PN are susceptible to root rot disease, which causes a huge loss and changes in the chemical components of this precious resource. In this study, sub-fractions of rot PN root extracts were preliminarily found to have admirable cytotoxicity on two human cancer cells. Further bioassay-guided isolation discovered nine new non-triterpenoids, including two novel N-methylacetamido-1-oxotetrahydropyrimidine alkaloids (1, 2), five 2H-furanones or 2H-pyranones (3-7), and two polyacetylenic alcohols (8, 9). Their structures were illuminated by extensive spectroscopic data, calculated ECD, and X-ray diffraction analysis. Among them, 3-7 were considered to be transformed from panaxatriol through the intermediates (8, 9). The new alkaloids (1, 2) displayed noteworthy cytotoxicity against five human cancer cells with IC50 values ranging from 14 to 24 µM. In silico target prediction and molecular docking studies showed that 1 and 2 may interact with EGFR, and were verified by the experimental inhibitory effect on EGFR tyrosine kinase.

New hydroperoxylated and 20,24-epoxylated dammarane triterpenes from the rot roots of Panax notoginseng.

BACKGROUND: Root rot is a serious destructive disease of Panax notoginseng, a famous cultivated araliaceous herb called Sanqi or Tianqi in Southwest China. METHODS: The chemical substances of Sanqi rot roots were explored by chromatographic techniques. MS, 1D/2D-NMR, and single crystal X-ray diffraction were applied to determine the structures. Murine macrophage RAW264.7 and five human cancer cell lines were used separately for evaluating the antiinflammatory and cytotoxic activities. RESULTS AND CONCLUSION: Thirty dammarane-type triterpenes and saponins were isolated from the rot roots of P. notoginseng. Among them, seven triterpenes, namely, 20(S)-dammar-25-ene-24(S)-hydroperoxyl-3ß,6α,12ß,20-tetrol (1), 20(S)-dammar-3-oxo-23-ene-25-hydroperoxyl-6α,12ß,20-triol (2), 20(S)-dammar-12-oxo-23-ene-25-hydroperoxyl-3ß,6α,20-triol (3), 20(S)-dammar-3-oxo-23-ene-25-hydroperoxyl-12ß,20-diol (4), 20(S),24(R)-epoxy-3,4-seco-dammar-25-hydroxy-12-one-3-oic acid (5), 20(S),24(R)-epoxy-3,4-seco-dammar-25-hydroxy-12-one-3-oic acid methyl ester (6), and 6α-hydroxy-22,23,24,25,26,27-hexanordammar-3,12,20-trione (7), are new compounds. In addition, 12 known ones (12-16 and 19-25) were reported in Sanqi for the first time. The new Compound 1 showed comparable antiinflammatory activity on inhibition of NO production to the positive control, whereas the known compounds 9, 12, 13, and 16 displayed moderate cytotoxicities against five human cancer cell lines. The results will provide scientific basis for understanding the chemical constituents of Sanqi rot roots and new candidates for searching antiinflammatory and antitumor agents.

GC-MS-based identification and statistical analysis of liposoluble components in the rhizosphere soils of Panax notoginseng.

Continuous cropping obstacle, mainly caused by microorganisms and organic components in soil, has become a serious problem for the plantation of Panax notoginseng (Araliaceae) due to the rapidly increased demands of this famous herbal medicine in recent decades. The rhizosphere soils cultivated with 3-year-old healthy and ill notoginseng were chemically investigated by gas chromatography-mass spectrometry (GC-MS) and compared with the corresponding soils without the plantation of notoginseng. Totally 47 liposoluble components were identified. Furthermore, the multiple statistical analysis showed that these constituents were qualitatively and quantitatively associated with the differences between the cultivated soil with P. notoginseng and the uncultivated soil. Among them, neophytadiene (4), d-α-tocopherol (38), (3ß,22E,24S)-ergosta-5,22-dien-3-ol (39), (3ß,24R)-ergost-5-en-3-ol (40), stigmasta-5,22-dien-3-ol (41), stigmast-4-en-3-one (44) and (5α)-stigmastane-3,6-dione (47) contributed most to the significant differences between the cultivated and uncultivated soils, whereas cyclopentadecane (3), octadecanoic acid methyl ester (16), docosanoic acid ethyl ester (31), nonacosane (34), 38 and 39 were found in much higher amount in the soils with ill P. notoginseng as compared to the case of those with the healthy P. notoginseng. On the other hand, liposoluble components in different cultivation areas were of great diversity; however, they were able to remain relatively consistent across the overall trend of differential substances.

Anti-inflammatory and Cytotoxic Triterpenes from the Rot Roots of Panax notoginseng.

Four new protopanaxatriol-type triterpenes (1-2) and glucosides (3-4), were isolated from the rot roots of Panax notoginseng (Burk.) Chen, along with four known ones (5-8). Their structures were elucidated on the basis of extensive spectroscopic analysis (HRESIMS, NMR, UV, IR, and OR) and acidic hydrolysis. The possible transformation pathway of these compounds were also speculated from ginsenoside Rg1. Compound 1, with a unique α,ß-unsaturated ketene in its side chain, showed significant inhibitory effects against NO production on Murine macrophage cells (IC50 = 4.12 ± 0.20 µM) and comparable cytotoxicities against five human cancer cell lines (myeloid leukemia HL-60, lung cancer A-549 cells, hepatocellular carcinoma SMMC7721, breast cancer MCF-7, and colon cancer SW480) to positive control, cisplatin (DDP).

Research of Panax spp. in Kunming Institute of Botany, CAS.

Panax, a genus of the Araliaceae family, is an important herbal group in traditional Chinese medicine (TCM). Nine species and three varieties are included in the genus of Panax, in which nearly all species have been used for medicinal purposes. Among them, Panax notoginseng (Burk) F. H. Chen, Panax ginseng C. A. Meyer and Panax quinquefolius L. are the most representative and valuable herbs world-wide, with a long history of cultivation. As the main bioactive chemical constituents, saponins with different aglycones are the major components in various Panax spp., and their pharmacological activities are mainly reflected in the effects on blood system, cardio- and cerebro-vascular systems, nervous system, metabolism, and immune regulation. Researchers of Kunming Institute of Botany (KIB), Chinese Academy of Sciences (CAS), have put many efforts into conducting the investigations on Panax species. Herein, we reviewed the research progress on Panax spp. in KIB, CAS, over the past few decades, from the aspects of history and origin, phytochemistry and pharmacological activities.