The study was conducted to investigate candidate materials as anti-inflammation agent from plant resources. Activities of 33 plant parts extracts with the final concentration of 5μg/ml were evaluated on the several inflammation-related markers such as the release of proinflammatoty cytokine [tumor necrosis factor-alpha (TNF-α) & interleukin-6 (IL-6)], nitric oxide (NO), the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and inhibitor of nuclear factor kappa-B alpha (Ik-Bα) in lipopolysaccharide (LPS)-treated RAW 264.7 cells. The extracts in the final concentration of 10 μg/ml were also screened on peroxynitrite (ONOO-) scavenging activity. Eleven extracts selected from the screening assay were verified on the inhibition activity on peroxynitrite and total reactive species oxygen (ROS) in the several concentrations. As results, Alpinia officinarum Hance (rhizome), Inula britannica var. chinensis Regel (flower), Ulmus arvifolia Jacq (trunk peel) and Aster scaber Thunb. (aerial part) showed comparatively potent anti-inflammatory activities in vitro cells or chemical level systems, and then these four plant parts should be studied on the antiinflammatory mechanism by further studies.

For the investigation of possibility as a useful functional material, different parts of Lythrum salicaria L. harvested at four growth stages were studied in the aspect of bleeding characteristics, chemical composition and in vitro activity. Weights (g/plant) of L. salicaria plant parts were high in order to stem 〉 leaf 〉 flower 〉 root at the best growth time. Crude lipids (3.59~4.30%) and crude proteins (14.7~23.5%) of L. salicaria leaves were the highest among the other plant parts showed from 0.08~3.54%, and 4.0~21.9%, respectively. Free sugars (2.9~4.2%) and crude ash (11.9~14.8) of leaves also showed the highest value. Free radical scavenging activities of L. salicaria root on 2,2-diphenyl-1-picrylhydrazyl showed from 43.5 μg/ml to 47.6 μg/ml as IC50 which were followed by those of flower, leaf, and stem. Root of L. salicaria tested at 100 μg/ml also showed the most efficient inhibitory effect on lipopolysaccharide (LPS)-induced nitric oxide (NO) production in murine macrophage RAW264.7 cells. Cell viability of the plant parts tested by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyl tetrazoliumbromide (MTT) assay was high in order to flower, leaf, root, and stem. Total phenol content measured as tannic acid equivalent showed the highest value in flower. In conclusion, among the plant parts, especially leaf of L. salicaria, was rich in the chemical components, and showed efficient antioxidant/inhibitory activity on free radical and NO production, and was expected to be a functional material candidate.

Fifty percent ethanol extract of Lythrum salicaria Linne root (LSR) was tested in vitro on antioxidant activity, and furthermore was investigated on antioxidative and fibrosis protecting activities in CCL4-induced liver fibrosis rat model. Ratio of hepatic GSH/GSSG (reduced glutathione/oxidized glutathione) as bio-parameter of antioxidant level in CCL4 plus LSR-treated rats for 6 weeks significantly increased from 2.8- to 5.7-fold than that of CCL4-treated rats at p 〈 0.05. Thiobarbituric acid reactive substances (TBARS) contents in CCL4 plus LSR-treated rats ranged from 1.57- to 2.19-fold of normal rats and were lower than those in CCL4 plus silymarin-treated rats (1.78~2.46-fold of normal rats) (p 〈 0.05). Amounts of hydroxyproline of liver tissue showing the content of total collagen, a parameter of fibrosis, in CCL4 plus LSR-administrated rat livers were 4.9~8.8μg/mg (-47~-71%, compared with that in CCL4-treated rat livers (16.6μg/mg tissue), which were significantly lower than those in CCL4 plus silymarin-administrated rats being 8.4~11.7μg/mg (-30~-50%). This collagen reducing effect of liver tissue in CCL4 plus LSR-treated rats was supported by histological observation using microscopy assay. From the results, we conclude that the root of L. salicaria have efficient antioxidant potential and effective antifibrotic activities.

A variety of herbs and plants have been traditionally used in oriental folk medicine for the treatment of inflammatory diseases. In our attempt to search for anti-inflammatory agents from natural products, we investigated 64 methanol extracts from 42 medicinal plants belonging to 10 families which were evaluated for inhibitory activities of NO production in lipopolysaccharide (LPS)-stimulated macrophage RAW 264.7 cells. Among them, 16 extracts exhibited inhibitory activities of NO production (IC50 values ranging from 59.6 to 94.7 μg/ml). Only the extract from aerial parts of Hosta lancifolia (H. lancifolia) did not exert cytotoxic effects at the concentrations tested. The extract from H. lancifolia decreased the mRNA and protein levels of inducible nitric oxide synthase (iNOS) and pro-inflammatory cytokines in activated macrophage RAW 264.7 cells in dose-dependent manner. The results suggest that the extract may contain bioactive compounds that suppress expression of pro-inflammatory cytokines, which may prove beneficial with regard to the development of natural agents for prevention and treatment of inflammatory diseases.