• Journal of Korean Society of Environmental Engineers
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• v.22 no.12
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• pp.2197-2204
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• 2000

Lignin is a major component of wastewater generated in the chemical processing of wood. Because it is recalcitrant, it inhibits biological treatment of wastewater of pulp manufacturing, especially high concentration of lignin may inhibit the anaerobic digestion. The objective of this study was to evaluate the toxicity of high molecular hardwood lignin (lignosulfonate, MW $\geq$ 20,000) on aceticlastic methanogens in the batch reactors at different temperatures with different sludge concentrations, using anaerobic serum bottles. The hardwood lignin was found to inhibit anaerobic conversion of acetate to methane and carbon dioxide, shown with a long lag-phase before methanogenesis started. The methanogens assumed not to be able to acclimate to the lignin were found to be acclimated slowly in the batch experiments, finally reaching non-toxic levels in which methane production could start. The hardwood lignin was found not to be bacteriocidal but bacteriostatic to aceticlastic methanogens. Hardwood lignin(lignosulfonate) at 1.3, 2.6, and 3.9%(w/w) inhibited the acetateutilizing methanogens of anaerobic digester sludge by 14.5, 17.8, 21.1 days(in noninhibitory condition it took 10 days) to produce the same amount of methane. The inhibitory effect of lignin was examined at temperature ranges of $30^{\circ}C$ to $50^{\circ}C$. When 2.6% of lignin was contained in wastewater, methane production was highest at $30^{\circ}C$ during initial 8 days. At $4^{\circ}C$, methane production rapidly increased after 12 days of digestion, the value became higher than that at $30^{\circ}C$ after 14 days. However, the methane production was completely inhibited during whole digestion period at $50^{\circ}C$. High ratio of lignin concentration to initial anaerobic sludge concentration gave tolerance to the inhibition. In this experiment, high molecular hardwood lignin was not degraded and decolorized.

• Journal of Food Hygiene and Safety
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• v.26 no.3
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• pp.222-226
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• 2011

Salmonellosis is a major bacterial zoonosis that causes self-limited enteritis to fatal infection in animals and food-borne infection and typhoid fever in humans. Multidrug-resistant strains of Salmonella spp. has increased over the last several decades and recently causes more serious problems in public health. The present study was investigated bacteriocidal effects of sodium chlorate, sodium azide, sodium cyanide, and sodium salts mixture containing sodium chlorate, sodium azide, and sodium cyanide on infection with S. typhimurium in macrophage RAW 264.7 cells, and antibacterial effects of sodium salts mixture for murine salmonellosis. In infection assay of S. typhimurium in RAW 264.7 cells, bacterial survival rates within macrophage in all treated groups was significantly reduced comparing to that of the control group with the passage of incubation time. Administration of sodium salts mixture showed a therapeutic effect for S. typhimurium infected ICR mice. The mortality of mice treated with sodium salts mixture was 70% until 12 days, while that of control mice was 100% until 9 days after S. typhimurium infection. The results of this study strongly indicate that sodium salts mixture has a potency treatment for murine salmonellosis.

• Microbiology and Biotechnology Letters
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• v.16 no.2
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• pp.111-118
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• 1988

The growth inhibition of enteropathogenic Escheriohia coli $A_2$and Escherichia coli G$_7$, causing the diarrhea in piglets, by the organic acid producing bacteria was studied in vitro. The metabolites of the organic acid bacteria, such as lactic acid, acetic acid inhibited the growth of E. coli $A_2$and E. coli G$_7$ in BL medium. The more the organic acid producing bacteria have ability to produce the organic acids, the higher these bacteria excelled the inhibitory efficacy against enteropathogenic E. coli. Among the strains examined, Lactobacillus casei Y and Streptococcus faecium C showed relatively strong growth inhibition against enteropathogenic E. coli.. When the organic acid producing bacteria and the enteropathogenic E. coli were incubated simultaneously in BL medium, bacteriostasis of E. coli was observed when the pH of BL culture was lowered to 5.0, and bacteriocidal effect was observed when the pH became Bess than 4.5, E. coli. $A_2$was more resistant to the organic acid bacteria than E. coli G$_7$.

• Korean Journal of Environmental Agriculture
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• v.27 no.2
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• pp.156-162
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• 2008

Salmonellosis is a major bacterial zoonosis that causes a variety of disease syndromes, self-limited enteritis to fatal infection in animals and food-borne infection and typhoid fever in humans. Recently, the emergence of multidrug resistant strains of Salmonella spp. causes more serious problems in environment and public health. The present study was investigated the antibacterial effect of Houttuynia cordata ethanol extract(HCEE) for murine salmonellosis. In the cytotoxic effect of HCEE on RAW 264.7 cells, there was no detectable effect with any concentrations between 25 and 100 ${\mu}g/ml$ after 8 h incubation. The bacteriocidal effect of HCEE was not showed on a Salmonella enterica serovar Typhimurium(S. typhimurium). HCEE makes morphological change of the RAW 264.7 cells, and there was significant decreased bacterial uptake and intracellular replication within Salmonella infected cells. And further nitric oxide(NO) production of Salmonella infected RAW 264.7 cells with HCEE was decreased comparing to RAW 264.7 cells without HCEE until 8 h post infection. Oral administration of HCEE showed a therapeutic effect for S. typhimurium infected BALB/c mice. The mortality of HCEE treated mouse was 80% until 12 days, while that of HCEE untreated mouse was 100 % until 8 days after lethal dose of S. typhimurium infection. These data suggested that HCEE has a potency treatment for intracellular replicative pathogen including salmonellosis, brucellosis, tuberculosis, listeriosis etc., and the application of HCEE makes new strategies for safety medicine development without antibiotic resistance bacterial appearance and residue problem in food and solves the public health problem from antibiotic mis- and over use.

• Journal of Veterinary Clinics
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• v.24 no.4
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• pp.550-556
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• 2007

The purpose of this study is to assess healing effect of the green tea on Staphylococcus contaminated wound. On the back of 7 dogs, 6 full-thickness skin wounds($2cm{\times}2cm$) were made and Staphylococcus intermedius was inoculated. Each wound was applied with the 2%(experimental group I), 1%(experimental group II) extract of green tea and normal saline(control group I) after inoculation. The wound contraction rate of the experimental group I and II was higher than that of the control group in entire period. And from the $6^{th}\;to\;22^{nd}$ day, the wound contraction rate of the experimental group I and II was significantly higher than that of the control group(p<0.05). The occupation rate of wound healing in the experimental group I was higher than that of the control group from $0\;to\;9^{th}$ day except from $1^{st}\;to\;2^{nd}$ day and also higher than that of the experimental group II from $0\;to\;3^{rd}$ day except from $1^{st}\;to\;2^{nd}$ day. And the occupation rate of wound healing in the experimental group II was higher than that of the control group from $1^{st}\;to\;8^{th}$ day except from $2^{nd}\;to\;3^{rd}$ day. According to concentration of green tea extract increased, the wound contracted more vigorously in earlier period. The tensile strength of the experimental group I and II was significantly higher than that of the control group(p<0.05). And that of the experimental group I was also higher than in the experimental group II(p<0.05). The number of S. intermedius in the experimental group I and II was decreased more rapidly than that of the control group. From the $4^{th}$ to the $11^{th}$ day, the number of S. intermedius in the experimental group I was significantly lower than that of the experimental group II and the control group. And from the $4^{th}$ to the $7^{th}$ day, the number of S. intermedius in the experimental group was significantly lower than that of the control group. The histopathological findings of the experimental group I and II were similar to those of the control group on the $1^{st}\;and\;4^{th}$ day. On $14^{th}$ day, reepithelialization was completed in the experimental group I and II except the control group. Higher wound contraction rate, better bacteriocidal action, higher tensile strength and better histopathological findings were observed in the experimental group I and II than in the control group. These results suggest that the topical application of green tea extract can promote contaminated wound healing in dogs.

• Journal of Society of Preventive Korean Medicine
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• v.16 no.1
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• pp.43-56
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• 2012

Objective : In this study, we assessed the anti-bacterial effects and epidermal permeability barrier function of red onion juice comparing to yellow onion juice and $Houttuynia$ $cordata$ extract $in$ $vitro$. Methods : 3types of red and yellow onion juice were prepared as antibacterial agent candidates with Houttuynia cordata hot water extract using 4 different bacterial strains ($Escherichia$ $coil$, $Salmonella$ $enterica$ $subsp.$ $enterica$, $Staphylococcus$ $epidermidis$, $Staphylococcus$ $aureus$ $subsp$) by colony counting method. The expression of filaggrin, a marker of keratinocyte differentiation, and serine palmitoyl transferase (SPT), a marker of the formation of the stratum corneum lipid barrier, in human HaCat keratinocytes were analyzed using HaCaT cell line. The expression of COX-2 and AP-1 which is a factor of COX-2 transcription were also analyzed by western blotting method. Results : There was detectable anti-bacterial effects on $Staphylococcus$ $epidermidis$, $Staphylococcus$ $aureus$ $subsp$ among 1%, 5%, 10% extracts of yellow and red onion.(81%-100%) The bacteriocidal effects were not shown on $Escherichia$ $coil$, $Salmonella$ $enterica$ $subsp.$ $enterica$ among $Houttuynia$ $cordata$, yellow onion and red onion extracts. The in vitro results showed the concentration-dependent effects on the expression of both filaggrin and SPT in HaCat cells among 0.01%, 0.05%, 0.1%, 0.5% extracts in Houttuynia cordata and red onion, reflecting the notion that $Houttuynia$ $cordata$ and red onion can induce epidermal keratinocyte differentiation and improve the recovery of skin barrier functions. The concentration-dependent effects also have been shown on the expression of both COX-2 and AP-1 among 0.01%, 0.05%, 0.1%, 0.5% extracts in $Houttuynia$ $cordata$ and red onion, while slight effect in yellow onion. Conclusion : Red onion juice could be a potential candidate enhanser for the skin care and cosmetology.