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This research was conducted to develop effective and safe marine-derived antiviral compounds against norovirus. The ethyl acetate (EtOAc)-extract from Eisenia bicyclis exhibited strong antiviral activity against murine norovirus (MNV) as a norovirus surrogate. Among the phlorotannins from E. bicyclis, dieckol (DE) and phlorofucofuroeckol-A (PFF) were known to possess the strongest antibacterial activity. In this study, DE and PFF were evaluated for antiviral activity against MNV. DE and PFF exhibited strong anti-MNV activity with 50% effective concentration (EC 50 ) of 0.9 μM. However, PFF exhibited more effective antiviral activity against MNV with higher selective index (668.87) than that of DE (550.60), due to its lower cell toxicity against RAW 264.7. This is the first report on the anti-MNV activity of phlorotannins from seaweed. The results obtained in this study suggest that the phlorotannins could be used as a potential source of natural antiviral agents.

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The objective of this study was to evaluate the antiviral activity of Phaeophyta extracts against feline calicivirus (FCV), used as a norovirus surrogate. A bioassay-guided cytotoxicity and virus infectivity assay revealed that methanolic extracts of Phaeophyta possessed significant antiviral activity against FCV. Among them, Eisenia bicyclis extract exhibited the highest antiviral activity against FCV. The 50% effective concentration of the extract (EC 50 ) inhibiting FCV viral replication by 50% was 80 µg/ mL. The extract also showed the highest selectivity index, calculated from the ratio of the median cellular cytotoxicity concentration (CC 50 ) and EC 50 , indicating antiviral efficacy against FCV. In addition, significant interruption of FCV infection was observed by pretreatment of host Crandall-Reese feline kidney cells with the E. bicyclis extract (200 µg/mL) prior to virus infection, in a dosedependent manner.

This study was performed to investigate the effects of flux and pre-treatment on the operation performance of a microfiltration drinking water treatment system through a pilot scale operation using lake water as raw water. The pilot plant had a capacity of 500 m3/day with a five membrane module and was operated for 1 year to carry out the experiments for the variation of filtration flux, physical cleaning conditions and pre-treatment conditions. Also, an experiment was performed when raw water with high turbidity flowed into the system as well as that pretreated with powdered activated carbon (PAC). When the MF system was operated with filtration flux of 2 m3/m2 day, it could not be operated more than 500 h due to the continuous TMP (Trans-membrane pressure) increase. In case of filtration flux of 1 m3/m2 day, the system could be operated continuously for more than 1300 hours without the increase in the TMP. During this experimentation period, raw water with high turbidity (above 400NTU) was fed into the membrane system. Therefore, the TMP increased by approximately 4.90 kPa compared to the TMP for the previous raw water with lower turbidity. In the case of the PAC pretreated membrane filtration process, the TMP tended to increase slightly. However, the TMP was reduced by performing coagulation and mixing after injecting PAC.

: 4,4'-diaminodiphenyl sulfone (dapsone) is a sulfone drug that has antibacterial effects on a variety of bacteria, especially Mycobacterium leprae; thus, it has been used to treat leprosy. Previous studies demonstrated that dapsone inhibits integrin-mediated adherence of neutrophils and production of prostaglandin E 2 by polymorphonuclear leukocytes. Hence, dapsone may act in immune cells and regulate cell-mediated inflammation processes. However, its antiinflammatory effects remain unclear. The present study demonstrated that dapsone modulates the production of inflammation-related cytokines in immune cells. We employed the spleen cells of mice, which are major immune cells, and lipopolysaccharide (LPS) as a causative agent of inflammation for experiments. Dapsone induced a proportional change in splenocyte subsets and the apoptosis of spleen cells. Interestingly, dapsone decreased the production of tumor necrosis factor-alpha and interleukin (IL)-10, but not IL-6, in LPS-treated spleen cells. In other assays, we measured the dapsone-induced production of nitric oxide (NO) and the expression of activation markers of spleen cells. Dapsone decreased NO production in LPS-treated spleen cells. Taken together, our results demonstrate that dapsone has antiinflammatory effects in immune cells and provide new insight into the potential uses of this agent.Keywords : anti-inflammatory activity, dapsone, inflammatory cytokines, spleen cells 서 론 재료 및 방법 실험동물과 시약C57BL/6과 BALB/c마우스는 오리엔트바이오(대한민국)에

: Bordetella (B.) bronchiseptica is a causative agent of swine atrophic rhinitis that promotes colonization of the mucous membrane of the swine nasal cavity by Pasteurella (P.) multocida. Mixed infection with B. bronchiseptica and P. multocida leads to growth inhibition of pigs, resulting in significant economic loss. There are many commercial vaccines for atrophic rhinitis, including B. bronchiseptica as a killed vaccine antigen (Ag). However, the immunogenicity of killed B. bronchiseptica Ag has not yet been elucidated; therefore, this study was conducted to investigate the immunogenicity of killed B. bronchiseptica Ag and the type of immune response it induces. In vitro assays using mouse spleen cells and flow cytometry revealed that B. bronchiseptica Ag induced high proliferation capability of lymphocytes, especially B lymphocytes, and the proliferating cells showed a significant response to interleukin (IL)-2. B. bronchiseptica Ag also enhanced the production of IL-12, a representative cytokine for cell-mediated immunity.In vivo experiments using mice showed that the injection of B. bronchiseptica Ag markedly induced Ag-specific antibody. Taken together, these results indicate that B. bronchiseptica Ag has high immunogenicity by itself. Keywords

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