• The Plant Pathology Journal
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• 제28권1호
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• pp.20-31
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• 2012

Endophytic bacterial communities of tidal flat plants antagonistic to oomycete plant pathogens were studied by the isolation of 256 root colonizing endophytic bacteria from surface-disinfected root tissues of six plants ($Rosa$ $rugosa$, $Suaeda$ $maritima$, $Vitex$ $rotundifolia$, $Carex$ $scabrifolia$, $Glehnia$ $littoralis$ and $Elymus$ $mollis$) growing in a tidal flat area of Namhae Island, Korea. To understand the antagonistic potential, an $in$ $vitro$ antagonistic assay was performed to characterize and identify strains that were antagonistic to the oomycete plant pathogens $Phytophthora$ $capsici$ and $Pythium$ $ultimum$ from the total population. Nine percent of the total number of isolated bacteria exhibited in vitro inhibitory activity against target plant pathogenic oomycetes. Taxonomic and phylogenetic placement of the antagonistic bacteria was investigated by analysis of the 16S rRNA gene sequences. The sequence analysis classified the antagonistic strains into four major classes of the domain bacteria ($Firmicutes$, ${\alpha}-Proteobacteria$, ${\gamma}-Proteobacteria$ and $Actinomycetes$) and 10 different genera. Further production of secondary metabolites, hydrolytic enzymes and plant growth promoting traits were determined for the putative new species of antagonistic endophytic bacteria. These new strains could not be identified as known species of ${\alpha}-Proteobacteria$, and so may represent novel bacterial taxa. The unexpected high antagonistic bacterial diversity associated with the tidal flat plants may be indicative of their importance in tidal flat plants as a promising source of novel antimicrobial compounds and biocontrol agents.

• Journal of Plant Biotechnology
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• 제34권2호
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• pp.145-152
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• 2007

Lactoferrin is an 80-kDa iron-binding glycoprotein known to exert many biological activities, such as facilitating iron absorption and having antimicrobial and anti-inflammatory effects. Rice can be a useful target for edible food plants to introduce human lactoferrin, because it has lower allergenicity and is likely to be safer than microorganisms or transgenic animals. A cDNA fragment encoding human lactoferrin (HLF) driven by the maize polyubiquitin promoter, along with herbicide resistance gene (bar) driven by CaMV 35S promoter, was introduced into rice (Oryza sativa L. cv. Dong Jin) using the Agrobacterium -mediated transformation system. Putative transformants were initially selected on the medium containing bialaphos. The stable integration of the bar and HLF genes into transgenic rice plants was further confirmed through polymerase chain reaction (PCR) and Southern blot analyses. The expression of the full length HLF protein from various tissues such as grains and young leaves of transgenic rice was verified by Western blot analysis. Analysis of progeny also demonstrated that introduced genes were stably inherited to the next generation at the Mendelian fashion.

• 한국임상수의학회지
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• 제34권4호
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• pp.261-267
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• 2017

The aim of this study was to investigate the antibacterial properties of chitosan silver nanocomposites (CAgNCs) using pathogenic Vibrio ichthyoenteri as a bacterial model. Results of agar disc diffusion and turbidimetric assays showed that CAgNCs could inhibit the growth of V. ichthyoenteri in concentration dependent manner. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of CAgNCs were 75 and $125{\mu}g/mL$, respectively. Furthermore, CAgNCs treatment induced the reactive oxygen species (ROS) level in V. ichthyoenteri cells in concentration and time dependent manner, suggesting that it generates oxidative stress, leading to bacterial cell death. The field emission scanning electron microscope (FE-SEM) images of CAgNCs treated V. ichthyoenteri exhibited strong cell membrane damage than un-treated control bacteria. MTT assay results showed the highest cell viability (22%) at $75{\mu}g/mL$ of CAgNCs treated bacteria samples. The results from this study suggest that CAgNCs is a potential antibacterial agent to control fish pathogenic bacteria.

• Preventive Nutrition and Food Science
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• 제22권2호
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• pp.138-143
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• 2017

The antifungal activity of isolated lactic acid bacteria (LAB) from a locally fermented cereal, "Kunu", was tested against toxigenic Aspergillus flavus. The liquid refreshment, "Kunu", was prepared under hygienic condition using millet, sorghum, and the combination of the two grains. The antifungal potential of isolated LAB against toxigenic A. flavus was carried out using both in vitro and in vivo antifungal assays. The LAB count from prepared "Kunu" ranged from $2.80{\times}10^4CFU/mL$ to $4.10{\times}10^4CFU/mL$ and Lactobacillus plantarum, Lactobacillus delbrueckii, Lactobacillus fermentum, Pediococcus acidilactici, and Leuconostoc mesenteroides were the isolated bacteria. Inhibitory zones exhibited by LAB against toxigenic A. flavus ranged from 5.0 mm to 20.0 mm. The albino mice infected with toxigenic A. flavus showed sluggishness, decrease in body weight, distortion of hair, and presence of blood in their stool, while those treated with LAB after infection were recovered and active like those in control groups. Except for the white blood cell that was increased in the infected mice as $6.73mm^3$, the packed cell volume, hemoglobin, and red blood cell in infected animals were significantly reduced (P<0.05) to 29.28%, 10.06%, and 4.28%, respectively, when compared to the treated mice with LAB and control groups. The antifungal activity of LAB against toxigenic A. flavus can be attributed to the antimicrobial metabolites. These metabolites can be extracted and used as biopreservatives in food products to substitute the use of chemical preservatives that is not appealing to consumers due to several side effects.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.411.1-411.1
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• 2014

This study evaluates the utility of an antibacterial microneedle composed of green tea extract (GT) and hyaluronic acid (HA), for the efficient delivery of GT. These microneedles have the potential to be a patient-friendly method for the conventional sustained release of drugs. In this study, a fabrication method using a mold-based technique to produce GT/HA microneedles with a maximum area of ${\sim}60mm^2$ with antibacterial properties was used to manufacture transdermal drug delivery systems. Fourier transform infrared (FTIR) spectrometry was carried out to observe the potential modifications in the microneedles, when incorporated with GT. The degradation rate of GT in GT/HA microneedles was controlled simply by adjusting the HA composition. The effects of different ratios of GT in the HA microneedles were determined by measuring the release properties. In HA microneedles loaded with 70% GT (GT70), a continuous higher release rate were sustained for 72 h. The in vitro cytotoxicity assays demonstrated that GT/HA microneedles are not generally cytotoxic to chinese hamster ovary cells (CHO-K1), human embryonic kidney cells (293T), and mouse muscle cells (C2C12), which were treated for 12 and 24 h. Antimicrobial activity of the GT/HA microneedles was demonstrated by ~95% growth reduction of gram negative [Escherichia coli (E. coli), Pseudomonas putida (P. putida) and Salmonella typhimurium (S. typhimurium)] and gram positive bacteria [Staphylococcus aureus (S. Aureus) and Bacillus subtilis (B. subtilis)], with GT70. Furthermore, GT/HA microneedles reduced bacterial growth in the infected skin wound sites and improved skin wound healing process in rat model.

• Biotechnology and Bioprocess Engineering:BBE
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• 제11권5호
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• pp.442-448
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• 2006

Human lactoferrin (hLf) is an iron-binding glycoprotein that has been considered to play many biological roles in the human, including the stimulation of the immune system, antimicrobial and anti-inflammatory effects, and regulation of iron absorption. We generated transgenic Siberian ginseng (Acanthopanax senticosus) cell cultures producing a functional hLf protein using the signal peptide sequence from the endoplasmic reticulum and driven by an oxidative stress-inducible SWPA2 promoter which is highly expressed in plant cell cultures. The production of hLf increased proportionally to cell growth and showed a maximal level (up to 3.6% of total soluble protein) at the stationary phase in suspension cultures. Full-length hLf protein was identified by immunoblot analysis in transgenic cell cultures of Siberian ginseng. Recombinant hLf (rhLf) was purified from suspension cells of Siberian ginseng by ammonium sulfate precipitation, cation-exchange and gel filtration chromatography. N-terminal sequences of rhLf were identical to native hLf (nhLf). The overall monosaccharide composition of rhLf showed the presence of plant specific xylose while sialic acid is absent. Antibacterial activity of purified rhLf was higher than that of nhLf. Taken together, we anticipate that medicinal Siberian ginseng cultured cells, as demonstrated by this study, will be a biotechnologically useful source for commercial production of functional hLf not requiring further purification.

• 대한한의학방제학회지
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• 제17권2호
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• pp.85-98
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• 2009

The fruits of Schisandra chinensis and Prunus mume have been traditionally used in the Oriental countries as an astringent against diarrhea and abdominal pain, a protectant for liver disease, an antimicrobial, and a blood tonic. However, little is known about the extract of Schizandrae Fructus and Mume Fructus (SMF-Ex) on dextran-sulfate sodium (DSS)-induced colitis in mice. In this study, we investigated the protective effects of SMF-Ex on DSS-induced colitis in mice. An experimental colitis was induced by daily treatment with 5% DSS. SMF-Ex was orally administrated the single dose (80 mg/kg, body weight/day) for 7 days with one time per day. SMF-Ex reduced significantly clinical sign of DSS-induced colitis, including body weight loss, shorten colon length, increased disease activity index (DAI), and histological colon injury. SMF-Ex also inhibited significantly nitric oxide (NO) and prostaglandine $E_2$ ($PGE_2$) productions in DSS-induced colitis mice. Furthermore, SMF-Ex increased significantly an superoxide anion (SOD), catalase, and glutathione peroxidase (Gpx) activity of the colon tissue in DSS-induced colitis mice. These results suggest that SMF-Ex administration could reduce significantly the clinical signs and inflammatory mediators, and increase antioxidant activity in DSS-induced colitis model mice and is a good candidate for further evaluation as an effective anti-ulcerative agent.

• Journal of Animal Science and Technology
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• 제60권5호
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• pp.8.1-8.9
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• 2018

Background: Indiscriminate use of antibiotics in livestock and poultry farming has caused emergence of new pathogenic strains. The situation has warrented the development of safe and alternative growth promoters and immunity enhancers in livestock. Herbal additives in animal and bird feed is a centuries-old practice. Thus, the present study investigated the efficacy of a standardized formulation of lipophilic turmeric extract containing curcumin and turmerones, (TF-36), as a natural growth promoter poultry feed additive. Methods: The study was designed on 180 one-day old chicks, assigned into three groups. Control group ($T_0$) kept on basal diet and supplemented groups $T_{0.5}$ and $T_1$ fed with 0.5% and 1% TF-36 fortified basal diet for 42 days. Each dietary group consisted of six replicates of ten birds. Body weight, food intake, food conversion ratio, skin colour, blood biochemical analysis and antioxidant status of serum were investigated. Results: Body weight improved significantly in $T_1$ with a 10% decrease in FCR as compared to the control. TF-36 supplementation in $T_1$ enhanced the antioxidant enzyme activity significantly (p < 0.05) with a decrease (p < 0.05) in lipid peroxidation. It also caused a slight yellow skin pigmentation without any change in meat color, indicating the bioavailability of curcumin from TF-36. However, no significant change in the concentration of serum creatinine, total protein and liver enzyme activities were observed, indicating the safety. Conclusion: In summary, we concluded that TF-36 can be a natural feed additive to improve growth performance in poultry, probably due to the better antioxidant activity and antimicrobial effects contributed by the better bioavailability of curcuminoids and turmerones. Besides, curcuminoids and turmerones were also known to be gastroprotective and anti-inflammatory agents.

• 식물병연구
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• 제19권3호
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• pp.177-182
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• 2013

Resvestrol has been known to inhibit bacterial and fungal growth in vitro, and can be accumulated in plant to concentrations necessary to inhibit microbial pathogens. Hence, stilbene synthase gene has been used to transform to synthesize resveratrol in heterologous plant species to enhance resistance against pathogens. In the present study, we investigated the antimicrobial activities of resveratrol and piceid to bacterial and fungal pathogens, which causing severe damages to rice plants. In addition, disease resistance was compared between transgenic rice varieties, Iksan 515 and Iksan 526 transformed with stlibene synthase gene and non-transgenic rice varieties, Dongjin and Nampyeong. Minimum inhibitory concentration of resveratrol for Burkolderia glumae was 437.5 ${\mu}M$, and the mycelial growth of Biplaris oryzae was slightly inhibited at concentration of 10 ${\mu}M$. However, other bacterial and fungal pathogens are not inhibited by resveratrol and piceid. The expression of the stilbene synthase gene in Iksan 515 and Iksan 526 did not significantly enhanced resistance against bacterial grain rot, bacterial leaf blight, sheath blight, and leaf blight. This study is the first report on the effect of resveratrol and piceid against pathogens of rice plant, and changes of disease resistance of transgenic rice plants transformed with stilbene synthase gene.

• 생약학회지
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• 제43권4호
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• pp.323-327
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• 2012

Acne, also known as Acne vulgaris, is a common disorder of human skin involving the sebaceous gland and Propionibacterium acnes (P. acnes). The purpose of this study was to demonstrate whether anti-acne herbal complex (AAHC), a functional extract from herbal complex can be used for acne treatment as a natural product. We first demonstrated anti-acne activity of AAHC in mouse acne model. Acne was induced by injecting P. acnes on the backside $2{\times}10^7$ CFUs in ICR mice and then the mice were treated with AAHC by dermal application once daily. ACFREE$^{(R)}$ (clindamicin phosphate) was used as a positive control. Treatment with AAHC decreased the P. acnes-induced skin swelling and inflammation. AAHC treatment significantly decreased serum DHT concentration in acne-induced mice. Especially, treatment of 20% AACH in mice was more effected than 40%. We next evaluated the antimicrobial property of AAHC against P. acnes, Staphylcococcus aureus (S.aureus), and Escherichia coli (E. coli). Incubation of P. acnes, S. aureus, and E. coli with AAHC showed minimal inhibitory concentration (MIC) values against the bacterial growth lower. Alamar blue method was also carried for the antibacterial activity. It was effectively MIC level at 6.25% of P. acnes. AAHC effectively inhibited the growth of S. aureus and E. coli at 0.097% on MIC level, respectively. Our results showed the potential of using AAHC as an alternative treatment for antibiotic therapy of acne and the application of AAHC as a herbal medicine for acne treatment.