Antioxidant Potential of Selected Korean Edible Plant Extracts.

This study aimed to evaluate the antioxidant activity of various plant extracts. A total of 94 kinds of edible plant extracts obtained from the Korea Plant Extract Bank were screened for cytotoxicity, following which the total phenolic content of 24 shortlisted extracts was determined. Of these, extracts from three plants, namely, Castanea crenata (CC) leaf, Camellia japonica (CJ) fruit, and Viburnum dilatatum (VD) leaf, were examined for antioxidant capabilities by measuring radical scavenging activity, ferric reducing/antioxidant power, and lipid peroxidation inhibitory activity. In addition, cellular antioxidant activities of the three extracts were assessed by a cell-based dichlorofluorescein assay and antioxidant response element (ARE) reporter activity assay. The results demonstrated that all three extracts concentration-dependently scavenged free radicals, inhibited lipid peroxidation, reduced the cellular level of reactive oxygen species, and increased ARE-luciferase activity, indicating antioxidant enzyme-inducing potential. In particular, CJ extract showed significantly greater antioxidative activity and antimigratory effect in a breast cancer cell line compared to CC and VD extracts. Hence, CJ extract deserves further study for its in vivo functionality or biologically active constituents.

Fermented red ginseng extract inhibits cancer cell proliferation and viability.

Red ginseng (Panax ginseng C.A. Meyer) is the most widely recognized medicinal herb due to its remedial effects in various disorders, such as cancers, diabetes, and heart problems. In this study, we investigated the anticancer effect of fermented red ginseng extract (f-RGE; provided by Jeonju Biomaterials Institute, Jeonju, South Korea) in a parallel comparison with the effect of nonfermented red ginseng extract (nf-RGE; control) on several cancer cell lines--MCF-7 breast cancer cells, HepG2 hepatocellular carcinoma cells, and reprogrammed MCF-7 cells (mimicking cancer stem cells). Cells were cultured at various concentrations of RGE (from 0.5 up to 5 mg/mL) and their viabilities and proliferative properties were examined. Our data demonstrate the following: (1) nf-RGE inhibited cell viability at ≥1 mg/mL for MCF-7 cells and ≥2 mg/mL for HepG2 cells, (2) in the presence of a carcinogenic agent, 12-O-tetradecanoylphorbol-13-acetate (TPA), nf-RGE treatment in combination with paclitaxel synergistically decreased MCF-7 as well as HepG2 cell viability, (3) f-RGE (which contained a greater level of Rg3 content) more effectively decreased the viability of MCF-7 and HepG2 cells compared to nf-RGE, and (4) f-RGE appeared more potent for inhibiting cancerous differentiation of reprogrammed MCF-7 cells in a synergistic fashion with paclitaxel, especially in the presence of TPA, compared to nf-RGE. These findings suggest that f-RGE treatment may be more effective for decreasing cancer cell survival by inducing apoptotic cell death and also presumably for preventing cancer stem cell differentiation compared to nf-RGE.

Platycosides from the Roots of Platycodon grandiflorum and Their Health Benefits.

The extracts and pure saponins from the roots of Platycodon grandiflorum (PG) are reported to have a wide range of health benefits. Platycosides (saponins) from the roots of PG are characterized by a structure containing a triterpenoid aglycone and two sugar chains. Saponins are of commercial significance, and their applications are increasing with increasing evidence of their health benefits. The biological effects of saponins include cytotoxic effects against cancer cells, neuroprotective activity, antiviral activity, and cholesterol lowering effects. Saponins with commercial value range from crude plant extracts, which can be used for their foaming properties, to high purity saponins such as platycodin D, which can be used for its health applications (e.g., as a vaccine adjuvant). This review reveals that platycosides have many health benefits and have the potential to be used as a remedy against many of the major health hazards (e.g., cancer, obesity, alzheimer's) faced by populations around the world. Methods of platycoside purification and analysis are also covered in this review.

Suppression of lipopolysaccharide-induced expression of inflammatory indicators in RAW 264.7 macrophage cells by extract prepared from Ginkgo biloba cambial meristematic cells.

CONTEXT: Ginkgo biloba L. (Ginkgoaceae) leaves have been used as an herbal medicine that has a complex range of biological activities. However, when we consider that biological activity of plant extracts is highly variable according to the source, location, and harvest season, technology to obtain the natural products with homogeneity is extremely important. OBJECTIVE: We established the technology to obtain the cambial meristematic cells (CMCs) of Ginkgo biloba, which were expanded in vitro with homogeneity through a suspension culture and then determined the anti-inflammatory activity of fractionated samples prepared from the ethanol extract of CMCs. MATERIALS AND METHODS: We determined the anti-inflammatory activity of samples using lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. Especially, influence of sample treatment on the expression of various indicators, such as nitric oxide (NO), inducible nitric oxide synthase (iNOS), cyclooxygenase (COX)-2, mitogen-activated protein (MAP) kinases, transcription factor, and cytokines, involved in inflammatory activity was assessed. RESULTS: A fractionated sample demonstrated 53.4% inhibition of LPS-induced NO production from the cells. Additionally, when fractionated samples were treated, iNOS and COX-2 expressions were almost completely suppressed. Fractionated samples also inhibited the phosphorylation of LPS-induced extracellular signal-regulated (ERK) and p38 MAP kinases more than 60%. IκB phosphorylation and subsequent nuclear factor (NF)-κB activation were also suppressed by fractionated samples. The expression of pro-inflammatory cytokines, IL-6 and tumor necrosis factor (TNF)-α, was significantly inhibited by the sample treatment. DISCUSSION AND CONCLUSION: Fractionated samples from the ethanol extract of Ginkgo biloba CMCs could potentially be the source of a powerful anti-inflammatory substance.