Kojongsi persimmon (Diospyros kaki L.) is the major cultivar of dried persimmon in Korea. The purpose of this study was to investigate the antioxidant and anti-inflammatory activities of water-soluble extracts from the calyx (PCE), peel (PPE) and leaf (PLE) of Kojongsi persimmon. PCE showed the highest total phenolic and flavonoid contents. In addition, the antioxidant activities (diphenylpicrylhydrazyl, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid), nitric oxide and reducing power) of PCE were higher than those of PPE and PLE. Moreover, PCE, PPE and PLE significantly suppressed the production of inflammatory mediators (nitric oxide and prostaglandinE 2 ) and pro-inflammatory cytokines (tumor necrosis factor-α and interluekin-1β) by lipopolysaccharide-stimulated RAW 264.7 cells in a dose-dependent manner. PCE showed the highest anti-inflammatory activity. Thus, these results suggest that the calyx of Kojongsi persimmon may be highly valuable as a natural product owing to its high-quality functional components as well as its-antioxidant, antiinflammatory activities.

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The red radish (Raphanus sativus L.; RR) sprout is a plant of the cruciferous family. In this study, we elucidated the effect of the water extract of RR sprout (RRSE) against α-amylase, α-glucosidase, and pancreatic lipase enzyme activity and adipogenesis in 3T3-L1 preadipocytes. α-amylase, αglucosidase, and pancreatic lipase enzyme activity was inhibited in a concentration-dependent manner by RRSE treatment. RSSE also abolished adipocyte differentiation and lipid and triglyceride accumulation without cytotoxicity in 3T3-L1 adipocytes. In addition, RRSE modulated the expression of the proteins related to adipogenic transcription factors: peroxisome proliferator-activated receptor (PPAR)γ, sterol regulatory element-binding protein 1 (SREBP-1), and CCAT/enhancer binding protein (C/EBP)α. RRSE also suppressed expression of the proteins responsible for lipid synthesis, transport, and storage: adiponectin, fatty acid synthesis (FAS), perilipin, and fatty acid bind protein-4 (FABP4). This study showed that RRS treatment has the potential to inhibit obesity by controlling the expression of adipogenic transcription factors and adipogenic proteins.

Diospyros lotus has been cultivated for its edible fruits, which are considered to have medicinal importance. The aim of this study was to evaluate the antioxidant and antipruritic activities of water-soluble, methanol extract, and ethyl acetate (EA) fractions from D. lotus leaves. The EA fraction showed the lowest IC50 vale (DPPH: 5.3 μg/mL, ABTS: 53.8 μg/mL). Therefore, we further investigated anti-inflammatory and antipruritic effects of the EA fraction. TNF-α production increased by PMA plus A23187 treatment was significantly inhibited by the EA fraction in a dose-dependent manner. The EA fraction also inhibited histamine release from rat peritoneal mast cells stimulated by compound 48/80, which promotes histamine release. Furthermore, EA fraction had inhibitory effects on scratching behavior induced by compound 48/80 in Balb/c mice. These results suggest that the EA fraction from D. lotus leaves has potential as ameliorative agent against oxidative stress and pruritus-related disease.

Perilla frutescens (L.) Britton var. sprouts (PFS) is a plant of the labiatae family. The purpose of this work was to assess the preventive effects of PFS ethanolic extracts (PFSEs) on cytokine-induced β-cell damage. Cytokines, which are released by the infiltration of inflammatory cells around the pancreatic islets, are involved in the pathogenesis of type 1 diabetes mellitus. The combination of interleukin-1β (IL-1), interferon-γ (IFN-γ), and tumor necrosis factor-α (TNF-α) induced formation of reactive oxygen species (ROS). Accumulation of intracellular ROS led to β-cell dysfunction and apoptosis. PFSEs possess antioxidant activity and thus lead to downregulation of ROS generation. Cytokines decrease cell viability, stimulate the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and induce the production of nitric oxide (NO). PFSEs prevented cytokine-induced cell viability in a dose-dependent manner. Incubation with PFSE resulted in significant reduction in cytokine-induced NO production that correlated with reduced levels of the iNOS and COX-2 protein expression. Furthermore, PFSE significantly decreased the activation of nuclear factor κB (NF-κB) by inhibition of IκBα phosphorylation in RINm5F cells. In summary, our results suggest that the protective effects of PFSE might serve to counteract cytokine-induced β-cell destruction. Findings indicate that consumption of Perilla frutescens (L.) Britton var. sprouts alleviates hyperglycemia-mediated oxidative stress and pro-inflammatory cytokine-induced β-cell damage and thus has beneficial anti-diabetic effects.Key words : Cytokines, diabetes, NF-κB, Perilla frutescents, RINm5F

Streptococcus mutans (S. mutans), which plays a major role in the etiology of human dental caries, is able to tolerate exposure to acid shock in addition to its acidogenicity. We investigated the effects of pH stress on membrane fluidity, activities and expression levels of F-ATPase, and proton permeability in S. mutans. Using 1,6-diphenyl-1,3,5-hexatriene, we observed membrane ordering at pH 4.8 and pH 8.8. The ordering effects were larger at pH 4.8 in cytoplasmic membranes isolated from S. mutans (CMSM). Increasing pH resulted in a decrease in the activities and expression levels of F-ATPase. The proton permeability was decreased at both acidic and alkaline pHs, and the lowest permeability was observed at pH 4.8. The lower permeability at pH 8.8 than pH 6.8 is likely to be caused by the decreased proton influx due to the decreased CMSM fluidity. In addition, it seems to be evident that extremely low permeability at pH 4.8 was caused by the decreased proton influx due to the decreased CMSM fluidity as well as the increased proton efflux due to the increased activity and expression level of F-ATPase. It is likely that CMSM fluidity and F-ATPase activity are two major key factors that determine proton permeability in S. mutans. We suggest that CMSM fluidity plays an important role in the determination of proton permeability, which sheds light on the possibility of using nonspecific membrane fluidizers, e.g., ethanol, for anti-caries purposes.

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