• Journal of Microbiology and Biotechnology
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• v.32 no.9
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• pp.1126-1133
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• 2022

This study investigated the contribution of lipoxygenase (LOX) inhibitors, nordihydroguaiaretic acid (NDGA), tetra-O-methyl nordihydroguaiaretic acid (M₄N) and zileuton (ZIL), and thromboxane A2 (TXA₂) inhibitor 4,5-diphenylimidazole (DPI) in the proliferation of Brucella abortus infection. None of the compounds affected the uptake of Brucella into the macrophages. We determined the effect of neutralizing leukotriene B4 (LTB4) receptor and showed that the uptake of the bacteria was inhibited at 30 min post-infection. M₄N treatment attenuated intracellular survival of Brucella at 2 h post-incubation but it was not observed in the succeeding time points. DPI treatment showed reduced survival of Brucella at 24 h post-incubation while blocking LTB4 receptor was observed to have a lower intracellular growth at 48 h post-incubation suggesting different action of the inhibitors in the course of the survival of Brucella within the cells. Reduced proliferation of the bacteria in the spleens of mice was observed in animals treated with ZIL or DPI. Increased serum cytokine level of TNF-α and MCP-1 was observed in mice treated with M₄N or ZIL while a lower IFN-γ level in ZIL-treated mice and a higher IL-12 serum level in DPI-treated mice were observed at 7 d post-infection. At 14 d post-infection, ZIL-treated mice displayed reduced serum level of IL-12 and IL-10. Overall, inhibition of 5-LOX or TXA₂ or a combination therapy promises a potential alternative therapy against B. abortus infection. Furthermore, strong ligands for LTB4 receptor could also be a good candidate for the control of Brucella infection.

• Journal of Microbiology and Biotechnology
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• v.19 no.8
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• pp.792-802
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• 2009

Antimicrobial peptides (AMPs) are considered to be a promising alternative to conventional antibiotics for future generations. We identified four novel hexapeptides with antimicrobial activity: KCM11 (TWWRWW-$NH_2$), KCM12 (KWRWlW-$NH_2$), KCM21 (KWWWRW-$NH_2$), and KRS22 (WRWFIH-$NH_2$), through positional scanning of a synthetic peptide combinatorial library (PS-SCL). The ability of these peptides to inhibit the growth of a variety of bacteria and unicellular fungi was evaluated. KCM11 and KRS22 preferentially inhibited the normal growth of fungal strains, whereas KCM12 and KCM21 were more active against bacterial strains. Bactericidal activity was addressed in a clear zone assay against phytopathogenic bacteria, including Pectobacterium spp., Xanthomonas spp., Pseudomonas spp., etc. KCM21 showed the highest activity and was effective against a wide range of target organisms. Application of KCM21 with inoculation of Pectobacterium carotovorum subsp. carotovorum on detached cabbage leaves resulted in an immune phenotype or a significant reduction in symptom development, depending on the peptide concentration. Cytotoxicity of the four hexapeptides was evaluated in mouse and human epithelial cell lines using an MTT test. The results revealed a lack of cytotoxic effects.

• Biomedical Science Letters
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• v.15 no.3
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• pp.233-239
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• 2009

The aim of this study was to evaluate the photodynamic effect of various photosensitizing agents against methicillin-resistant Staphylococcus aureus (MRSA). MRSA was exposed to light from a 632 urn diode laser (15 J/$cm^2$) in the presence of various photosensitizer, such as photofrin, photogem, radachlorine and ALA. In vivo study was performed using ICR mice. Twenty eight mice had a standard wound ($100\;mm^2$) created on the dorsum, and MRSA was inoculated into the wound region. The four groups were classified as follows: (1) the untreated control group (bacteria alone), (2) the bacteria plus light group (15 J/$cm^2$), (3) the bacteria plus photofrin group (kept in the dark), and (4) the photodynamic therapy (PDT) group (bacteria, photofrin, and light). After photofrin (dose 1 mg/kg) injection, the experimental group was irradiated with 632 urn diode laser (15 J/$cm^2$) for 30 minutes after In vitro results of PDT showed the complete killing of MRSA at the photofrin, radachlorine, and photogem However, ALA-PDT was ineffective on MRSA viability. In vivo results showed that photofrin has therapeutic effect on the wound infection. These results demonstrate that selective lethal photosensitization of MRSA can be achieved using phofrin, photogem and radachlorin. Thus, PDT can inactivate MRSA survival.

• Journal of Applied Biological Chemistry
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• v.56 no.1
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• pp.49-51
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• 2013

In a previous study, we reported that 13(E)-labd-13-ene-$8{\alpha}$,15-diol (13E) possesses antiviral and anticancer activities. In this study, the anticancer and antimicrobial activities of 13(E) were evaluated against 4 cancer cell lines and 6 bacteria. 13(E) showed inhibitory effect on a variety of cancer cell lines. The $IC_{50}$ values was 8.3-21.3 ${\mu}g/mL$. 13(E) was the most effective growth inhibitor of murine leukaemia cell lines P388, producing approximately 8.3 ${\mu}g/mL$ of $IC_{50}$ in the cytopathic effect (CPE) method. 13(E) also inhibited the growth of the gram-positive bacteria (Staphylococcus aureus, Bacillus cereus and Listeria monocytogenes) and gram-negative bacteria (Vibrio parahaemolyticus, Escherichia coli and Salmonella enteritidis) with a range of minimum inhibitory concentration (MIC) values from 0.092 to 0.598 mg/mL and gram-negative bacteria were more sensitive to the compound (MIC, 0.092 mg/mL).

• The Journal of Advanced Prosthodontics
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• v.4 no.2
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• pp.84-88
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• 2012

PURPOSE. To evaluate the efficacy of sodium hypochlorite (1 : 10) and iodophor disinfectants on alginate impressions along with their effect on the survived bacterium count on the gypsum cast. MATERIALS AND METHODS. Four alginate impression on each dentate patients were made, of which Group I were not washed or disinfected, Group II impressions were merely washed with water, Group III were disinfected by spraying with sodium hypochlorite (1 : 10), Group IV were disinfected with iodophor (1 : 213). Gypsum cast (type III) were made from all the impression. Impressions and gypsum cast were swabbed in mid palatal region for bacterial culture. Bacterial colony counting done after 3 days of incubation at $37^{\circ}C$ in blood agar media. The data obtained was analyzed by one way ANOVA test at a significant difference level of 0.05. RESULTS. Group I and Group II showed significantly more bacteria compared to Group III and Group IV. Bacterial colonies on the alginate impression and gypsum cast in group disinfected with Sodium hypochlorite (1 : 10) were 0.18, 0.82 respectively compared to group treated with iodophor (1 : 213). There was an increase in bacterial count on dental cast compared to source alginate impressions. CONCLUSION. Sodium hypochlorite (1 : 10) was found to be better disinfectant for alginate impression. There was an indication of increase in number of bacteria from alginate impression to making of dental cast. Additional gypsum cast disinfectant procedures need to be encouraged to completely eliminate cross infection to dental laboratory.

• Journal of fish pathology
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• v.20 no.1
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• pp.33-40
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• 2007

Biochemical characteristic of Streptococcus iniae and Streptococcus parauberis that are pathogens of streptococcosis of cultured flounder, Paralichthys olivaceus, in Jeju area was examined. The result of experiments on the grow according to temperatures showed that only S. parauberis grew at 10℃, the result of hemolysis test showed that only S. iniae bacteria showed β hemolysis. Only S. parauberis were positive in VP test and HIP test, both bacteria used α-D-glucose, D-mannose, D-psicose, D-trehalose, pyruvatic acid methyl ester, and glycerol as substrates. L-lactic acid was used only S. iniae bacteria, and β-methyl-D-glucosid was used only by S. parauberis. S. iniae exhibited acute infection patten, differently S. parauberis exhibited chronic infection patten in pathogenic test.

• The Korean Journal of Health Service Management
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• v.11 no.4
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• pp.203-211
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• 2017

Objectives : This study aims to design a method for drying forceps jars. As part of the process, holes were made in the forceps jars. Drying time, rate of wet pack, and cost of rewashing linen were then determined. Moreover, the study looked into the bacteria incidence rate in the forceps jars. This study suggests a practical way for preventing infection in a hospital through a surgical device. Methods : This study investigated the effect of forceps jars with holes on reducing drying time, rate of wet pack, and cost of rewashing linen. It also looked into the bacteria incidence rate in the forceps jars through a parallel design. Data was collected and analyzed using SPSS version 21. Results : The drying time of a forceps jars was remarkably reduced from $18.44{\pm}0.2$ minutes(non-hole forceps jars) to $0.58{\pm}0.02$ minutes(4-hole forceps jars). The rate of wet pack of non-hole forceps jars was 51.4%. However, the rate of 4-hole forceps jars reached 4.6%. The cost of rewashing linen saw a decline from 38,073 won to 3,381 won. In addition, no bacteria and virus were detected from the 24-hours usage of forceps jars even though the jars had holes. Conclusions : The 4-hole forceps jars greatly increased work efficiency as a result of the reduced drying time, rate of wet-pack and cost of rewashing linen. The 4-hole forceps jars did not influence their sterilizing effect.

• Preventive Nutrition and Food Science
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• v.9 no.2
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• pp.161-166
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• 2004

The effects of kimchis intake on Helicobacter pylori infection in the stomach, the counts of lactic acid bacteria in the large intestine, and bacterial enzymes ($\beta$-glucosidase, $\beta$-glucuronidase) and pH in feces were examined. A total of 20 participants (age range 34 ∼ 57) were assessed for H. pylori infection status by Be urea breath test. Fourteen participants were eliminated because they were H. pylori-negative. This study consisted of 4 consecutive phase, each of which lasted 4 weeks. Three hundred grams of kimchi were administered to H. pylori-infected subjects during the kimchi phase, followed by 4 weeks of control phase. During the control phase, subjects consumed 60 g of kimchi, the minimum amount in their customary diets. All participants were found to be H. pylori-positive during all experimental periods. During the kimchi phase, delta over baseline (DOB) level was lower than during the control phase, although significant difference between the kimchi and control phases were not found (p=0.9439). However, the counts of Lactobacillus sp. and Leuconostoc sp. significantly (p < 0.0005) increased during the kimchi phase. $\beta$-Glucosidase and $\beta$-glucuronidase activities and pH were significantly decreased by kimchi intake compared to control (p=0.000l). These results suggested that kimchi consumption did not show any therapeutic effect on H. pylori in the stomach. However, kimchi seemed to be a good food for colon health, since it increased the beneficial bacteria such as lactobacillus and decreased toxic enzyme ($\beta$-glucosidase and $\beta$-glucuronidase) activity and pH.

• Mycobiology
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• v.29 no.4
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• pp.218-223
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• 2001

A rapid radicle assay for prescreening antagonistic bacteria to Phytophthora capsic4 causal agent of Phytophthora blight of pepper was developed. Sixty-four bacterial strains with in vitro antifungal activity selected out of 1,400 strains isolated from soils of Ansung, Chunan, Koyang, and Paju, Korea in 1998 were used for development of the bioassay. Uniformly germinated pepper seeds dipped in bacterial cells for 3 hours were placed near the edges of growing mycelia of P. capsici on water agar containing 0.02% glucose. Five-week-old pepper plants(cv. Nockwang) were inoculated to compare with results of the radicle assay developed in this study. For plant inoculation, pepper seeds were sown in potting mixtures incorporated with the bacterial strains, then transplanted into steam-sterilized soils 3 weeks later. Plants were hole-inoculated with zoospores of P. capsici 2 weeks after transplanting. Disease incidence and severity were determined in radicle and plant assessments, respectively. In radicle assay, six strains, GK-B15, GK-B25, OA-B26, OA-B36, PK-B09, and VK-B14 consistently showed the significant(P=0.05) disease reduction against radicle infection by the fungus, four of which also did in plant assessments. Strains OA-B36 and GK-B15 consistently reduced the fungal infection in both the radicle assay and the plant assessment. Therefore, prescreening strains using the radicle assay developed in this study followed by plant assay could reduce time and labor, and improved the possibility of selecting antagonistic bacteria for control of Phytophthora blight of peppers.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.408-420
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• 2016

This study proposes an alternative approach for the use of chitosan silver-based dressing for the control of foot infection with multidrug-resistant bacteria. Sixty-five bacterial isolates were isolated from 40 diabetic patients. Staphylococcus aureus (37%) and Pseudomonas aeruginosa (18.5%) were the predominant isolates in the ulcer samples. Ten antibiotics were in vitro tested against diabetic foot clinical bacterial isolates. The most resistant S. aureus and P. aeruginosa isolates were then selected for further study. Three chitosan sources were tested individually for chelating silver nanoparticles. Squilla chitosan silver nanoparticles (Sq. Cs-Ag⁰) showed the maximum activity against the resistant bacteria when mixed with amikacin that showed the maximum synergetic index. This, in turn, resulted in the reduction of the amikacin MIC value by 95%. For evaluation of the effectiveness of the prepared dressing using Artemia salina as the toxicity biomarker, the LC₅₀ was found to be 549.5, 18,000, and 10,000 μg/ml for amikacin, Sq. Cs-Ag⁰, and dressing matrix, respectively. Loading the formula onto chitosan hydrogel dressing showed promising antibacterial activities, with responsive healing properties for the wounds in normal rats of those diabetic rats (polymicrobial infection). It is quite interesting to note that no emergence of any side effect on either kidney or liver biomedical functions was noticed.