Chem. Pharm. Bull.(オピニオン)

Natural stilbenes: an overview

Medicinal and therapeutic potential of Sea buckthorn (Hippophae rhamnoides L.)

Medicinal plants of the Dendrobium genus are highly prized, and hence, methodologies have been developed to authenticate Dendrobium drugs from its adulterants. Many bioactive constituents of Dendrobium species have been identified. The macromolecules included lectins; the enzymes chalcone synthase, sucrose synthase, and cytokinin oxidase; and polysaccharides. The polysaccharides display immunomodulatory and hepatoprotective activities. Alkaloids exhibit antioxidant, anticancer, and neuroprotective activities. Other compounds manifest antioxidant, anticancer, and immunomodulatory.

Review of research on Dendrobium, a prized folk medicine.

https://www.rsc.org/suppdata/np/c2/c2np20049j/c2np20049j.pdf

Natural stilbenoids: distribution in the plant kingdom and chemotaxonomic interest in Vitaceae

In our investigation on the chemical constituents of Hippophae rhamnoides L., the chloroform-soluble fraction of the 80% acetone extract of branch bark was observed to inhibit nitric oxide (NO) production in a lipopolysaccharide and recombinant mouse interferon-γ-activated murine macrophage-like cell line, RAW 264.7 cells. Two new triterpenoids, 2-O-trans-p-coumaroyl maslinic acid (1) and 2-O-caffeoyl maslinic acid (2), and three known triterpenoids, oleanolic acid (3), 3-O-trans-p-coumaroyl oleanolic acid (4), and 3-O-caffeoyl oleanolic acid (5), and 6-methoxy-2H-1-benzopyran (6) and β-sitosterol (7) were isolated from the branch bark extract. Their inhibitory activities on the production of NO in RAW 264.7 cells and radical-scavenging activities were examined.

Triterpenoids from Hippophae rhamnoides L. and Their Nitric Oxide Production-Inhibitory and DPPH Radical-Scavenging Activities

9, 10-Dihydrophenanthrene derivatives from Pholidota yunnanensis and scavenging activity on DPPH free radical

New phenanthrenes, loddigesiinols A (1) and B (7), and stilbenes, loddigesiinols C (8) and D (9), were isolated from 80% ethanol extract of Dendrobium loddigesii ROLFE (Orcharedceae) along with known compounds, including five phenanthrenes, three stilbenes, two lignans, and three sterols. Their structures were determined by spectroscopic studies. These compounds were evaluated for their inhibitory activities against nitric oxide (NO) production and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging. Phenanthrenes (1-3, 7) and dihydrophenanthrenes (4-6) showed significant inhibitory activity against NO production. In particular, 2 showed stronger inhibitory activity against NO production than 5 and 6. This suggested that this phenanthrene is a stronger inhibitor of NO production than dihydrophenanthrene. The new phenanthrenes, loddigesiinols A (1) and B (7), significantly inhibited NO production with IC(50) values of 2.6 and 10.9 muM, respectively. One new dihydrostilbene, loddigesiinol D (9), showed weak inhibitory activity against NO production with an IC(50) value of 69.7 microM, but the other new dihydrostilbene, loddigesiinol C (8), did not show this activity at 100 microM.

New Phenanthrenes and Stilbenes from Dendrobium loddigesii

In vitro anti-allergic screening of medicinal herbal extracts revealed that the chloroform extract of the rhizoma of Kadsura coccinea inhibited nitric oxide (NO) production in a lipopolysaccharide (LPS) and recombinant mouse interferon-gamma (IFN-gamma) activated murine macrophage like cell line RAW 264.7. Further fractionation of the chloroform extract led to the isolation of three new lignans, including two dibenzocyclooctadiene lignans and one arylnaphthalene lignan, together with other three known dibenzocyclooctadiene lignans. This is the first report of NO production inhibitory activity of Kadsura coccinea and first report about the isolation of arylnaphthalene lignan from K. coccinea.

New lignans from Kadsura coccinea and their nitric oxide inhibitory activities.

Ethyl acetate extract of Pholidota chinensis L. showed strong NO production inhibitory activity in murine macrophage-like cell line, RAW 264.7, which was activated by a lipopolysaccharide (LPS) and interferon-gamma (IFN-gamma). Fractionation of the active extract led to the isolation of two new stilbene derivatives, 2,3'-dihydroxy-5-methoxy-3,4-methylenedioxydihydrostilbene (Pholidotol A) and 2-hydroxy-5-methoxy-3,4,3',4'-dimethylenedioxydihydrostilbene (Pholidotol B) together with six known stilbene derivatives. Pholidotols A both B and inhibited Nitric oxide (NO) production with an IC(50) value at 24.3 and 17.1 microM, respectively.

Jue Wang

Papers

Triterpenoids from Hippophae rhamnoides L. and Their Nitric Oxide Production-Inhibitory and DPPH Radical-Scavenging Activities

9, 10-Dihydrophenanthrene derivatives from Pholidota yunnanensis and scavenging activity on DPPH free radical

New Phenanthrenes and Stilbenes from Dendrobium loddigesii

New lignans from Kadsura coccinea and their nitric oxide inhibitory activities.

Stilbene derivatives from Pholidota chinensis and their anti-inflammatory activity.