• Weed & Turfgrass Science
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• v.2 no.2
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• pp.202-206
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• 2013

Biocontrol potential of an isolate of Helicosporium spp. against Rhizoctonia solani, Fusarium oxysporium and Phytophthora drechsleri was evaluated in vitro and in vivo. A selected biocontrol agent designated as Helicosporium 0635BP strongly inhibited growth and lysed mycelium of Rhizoctonia solani and Fusarium oxysporium on PDA. Autoclaved culture filtrate of the agent also completely inhibited growth of the turfgrass large patch pathogen, R. solani AG2-2 IV at the concentration of 50 ml $L^{-1}$. The pathogen was killed when dipped under the 20% filtrate for four hours or 50% for one hr. In a field trial, plots applied with the crude or times diluted culture filtrate showed 100% control efficacy of the turfgrass large patch as a chemical applied for a comparison. Results indicated that Helicosporium 0635BP is a promising biocontrol agent on control of the turfgrass large patch disease and its culture filtrate contained unknown heat suitable antifungal substance (s). Further studies on mass production, purification and identification of the unknown compound (s) are in progress for practical use.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.5 no.1
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• pp.33-38
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• 2002

Purpose: The incidence of shigellosis had been decreased due to the use of antibiotics and the improvement of environmental sanitation but recently increases again. Shigellosis occurrs in mass outbreak through unsanitized meal preperation refered from welfare facility and school. We observed epidemic aspect and clinical coarse of childhood shigellosis. Methods: from December 2001 to January 2002, 22 inpatients with shigellosis in Dongbu Municipal Hospital were observed epidemiologically, clinically and microbiologically. Results: 1. The sexual ratio was 1:1 and mean age was $5.5{\pm}1.4$ years (14 months to 11 years). 2. The clinical manifestations were following: diarrhea (95.5%), high feve (10%) and asymptomatic (4.5%). The mean duration was $3.9{\pm}2.1$ days (1 to 12 days). All patients had no complication and normal serologic test. 3. S. sonnei was cultured in rectal swab, and was resistant to TMP/SMX and ampicillin, but susceptible to ampicillin/sulbactam and the 3rd generation cephalosporins. 4. The patients were treated by antibiotics with conservative treatment including electrolytes and fluid therapy for 5 days, resulting in improvement confirmed by negative reaction on stool culture. 5. These cases were all occurred in mass outbreak in day care center and were suspected to be secondary infection by members of family. Conclusion: This shigellosis occurred in day care center was secondary infection due to S. sonnei and had mild clinical coarse and improvement after antibiotic treatment.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 1994.06a
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• pp.11-26
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• 1994

Crown gall of stonefruit and nut trees is one of the very few plant diseases subject to efficient biological control. The disease is caused by the soil-inhabiting bacteria Agrobacterium tumefaciens and Agrobacterium rhizogenes and the original control organism was a non-pathogenic isolate of A. rhizogenes strain K84. Control is achieved by dipping planting material in a cell suspension of strain K84 which specifically inhibits pathogenic strains containing a nopaline Ti plasmid. Because the agrocin 84-encoding plasmid (pAgK84) is conjugative, it can be transmitted from the control strain to pathogenic strains which, as a result, become immune to agrocin 84 and cannot be controlled. To prevent this happening, the transfer genes on pAgK84 were located and then largely eliminated by recombinant DNA technology. The resulting construct, strain K1026, is transfer deficient but controls crown gall just as effectively as does strain K84. Field data from Spain confirm that pAgK84 can transfer to pathogenic recipients from strain K84 but not from strain K1026. The latter has been registered in Australia as a pesticide and is the first genetically engineered organism in the world to be released fro commercial use. It is recommended as a replacement for strain K84 to prevent a breakdown in the effectiveness of biological control of crown gall. Several reports indicate that both strains K84 and K1026 sometimes control crown gall pathogens that are resistant to agrocin 84. A possible reason for this is that both strains produce a second antibiotic called 434 which inhibits growth of nearly all isolates of A. rhizogenes, both pathogens and non-pathogens. Crown gall of grapevine is caused by another species, Agrobacterium vitis. It is resistant to agrocin 84 and cannot be controlled by strains K84 or K1026. It is different from other crown gall pathogens in several characteristics, including the fact that, although a rhizosphere coloniser, its also lives systemically in the vascular tissue of grapevine. Pathogen free propagating material can be obtained from tissue culture or, less surely, by heat therapy of dormant cuttings. A number of laboratories are searching for a biocontrol strain that will prevent, or at least delay, reinfection. A non-pathogenic A. vitis strain F/25 from South Africa looks very promising in this regard.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.46 no.4
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• pp.339-348
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• 2020

The purpose of this study was to investigate the possible use of the Boehmeria nivea var. nipononivea extract and fractions for the development of natural cosmetic ingredients. The leaves of B. nivea var. nipononivea, extracted by 70% ethanol, were sequentially fractionated with n-hexane, dichloromethane, ethylacetate, and n-butanol. As a result of DPPH and ABTS test, ethyl acetate fractionation was shown to be excellent in radical scavenging activity. For the antimicrobial activities against Staphylococcus aureus, Staphylococcus epidermidis, Cutibacterium acnes and antibiotic resistant strains, MIC and birth control rate were observed by paper disc method. In the antibacterial activity by the disc diffusion assay against S. aureus, S. epidermidis and C. acnes, the dichloromethane and ethylacetate fraction showed stronger antibacterial activity than the other fractions and extract. Moreover, the ethylacetate fraction showed strong nitric oxide (NO) production inhibitory effect in lipopolysaccharide (LPS)-stimulated RAW 264.7 cell. In conclusion, we found that B. nivea var. nipononivea extract was not cytotoxic and showed antioxidant, antimicrobial and anti-inflammatory effects. These results suggest that the Boehmeria nivea var. nipononivea extract and fractions could be applied as an effective cosmetic material with antioxidant activity.

• Korean Journal of Clinical Laboratory Science
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• v.54 no.1
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• pp.15-22
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• 2022

Procalcitonin (PCT) can provide an experimental rationale and a diagnostic lead to distinguish between bacterial and viral infections. This study sought to investigate the clinical characteristics and prognosis of patients with high PCT levels, to improve clinical diagnosis, and to determine whether PCT levels were associated with the subsequent development of sepsis in the general population. This was a retrospective observational study conducted on outpatients (N=127) over a year. The general data and laboratory parameters studied were PCT, C-reactive protein (CRP), and complete blood count (CBC). The positive rates of CRP and white blood cells (WBCs) in the elevated PCT group were higher than those of the normal group (P<0.05); the specificity and sensitivity of the PCT levels were obviously higher than those of the CRP and WBC levels at diagnosis (P<0.05). The mean PCT levels in the low group were significantly higher than those in the high or moderate group (P<0.001). There was a significant positive correlation with CRP, total WBCs, and neutrophils (P<.001). The main finding of this study was the significant association between an elevated PCT level and CRP and WBC levels, signifying a high diagnostic value. This has important implications for the diagnosis of bacterial infections and therapeutic implications for the use of antibiotic treatment in specific patients.

• Journal of Life Science
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• v.33 no.10
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• pp.842-850
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• 2023

Pyrrolnitrin, pyrrolomycin, and pyoluteorin are functional halogenated phenylpyrrole derivatives (HPDs) derived from microorganisms with diverse antimicrobial activities. Pyrrolnitrin is a secondary metabolite produced from L-tryptophan through four-step reactions in Pseudomonas fluorescens, Burkholderia cepacia, Serratia plymuthica, etc. It is currently used for the treatment of superficial dermatophytic fungal infections, has high antagonistic activities against soil-borne and foliar fungal infections, and has many industrial applications. Since pyrrolnitrin is easily decomposed by light, it is difficult to widely use it outdoors. As an alternative, fludioxonil, a synthetically produced non-systemic surface fungicide that is structurally similar and has excellent light stability, has been commercialized for seed and foliar treatment of plants. However, due to its high toxicity to aquatic organisms and adverse effects in human cell lines, many countries have established maximum residue levels and strictly control its levels. Pyrrolomycin and pyoluteorin, which have antibiotic/antibiofilm activity against Gram-positive bacteria and high anti-oomycete activity against the plant pathogen Pythium ultimum, respectively, were isolated and identified from microorganisms. This review summarizes the biosynthesis and production of natural pyrrolnitrin derived from bacteria and the characteristics of synthetic fludioxonil and other natural phenylpyrrole derivatives among the HPDs. We expect that a plethora of highly effective, novel HPDs that are safe for humans and environments will be developed through the generation of an HPD library by microbial biosynthesis and chemical synthesis.

• Journal of Yeungnam Medical Science
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• v.27 no.2
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• pp.113-121
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• 2010

Background and purpose : Patients with acute leukemia experience prolonged periods of neutropenia due to their disease or its treatment. For this reason, they often develop serious infectious complications. Although antibiotic therapy has improved in recent years, the fatality rate from infection remains high. For the control of infection, protected environment was developed. But because of economic issue, most of chemotherapy with acute myeloid leukemia have conducted in non-protected environment. So this study compared the rate of complete remission, days with neutropenia, rate of fever, rate of positive culture, rate of overt infection and use of antibacterial and antifungal agents with patients within non-protected environment and protected environment, retrospectively, Patients with acute myeloid leukemia during first remission induction chemotherapy were eligible for this study, Methods : Retrospective analysis was conducted between patients in non-protected (25 patients) and protected environment (14 patients) with acute myeloid leukemia during remission induction chemotherapy Results : Rate of overt infection, rate of fever, rate of positive culture and rate of use of antibiotics were significantly high in patients within non-protected environment compared with patients within protected environment. There were no differences in rate of complete remission and days of neutropenia Conclusions : This study suggests protected environment for patients with acute myeloid leukemia during remission induction chemotherapy could reduce rate of overt infection, and rate of use of antibiotics.

• Journal of dental hygiene science
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• v.1 no.1
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• pp.46-52
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• 2001

The purpose of this study was to examine dental personnels' concern for health, their personal protection manner, and whether or not they were inoculated against hepatitis B and made an inquiry of patients about that. It's ultimately meant to serve as a basis for the preparation of an anti-infection guide for the protection of dental personnels against all sorts of infectious diseases. After a survey was conducted from March 29 through May 9, 2001, the following findings were obtained: (1) The dental personnel group that had worked for 5 to less than 7 years took health examination the most, with 71.4%, before joining the hospital, and 61.5% of those who had served for 9 years or more, the greatest percentage, took medical checkup after joining the hospital(P<0.05). (2) The largest percentage of being inoculated against the anti-B type hepatitis after employment was 71.4% of the dental personnels over 35, and 57.7% of those with 9-year or more working experiences. Therefore, their age and service term made a significant difference(P<0.05). (3) There was no significant gap in personal protection practices between the dental hygienists and nurse aids(P>0.05). But the use of safety goggles for treatment was not properly done, with just 1.48 on the basis of 3 points, whereas the use of mask was scored 2.40 and the use of gloves was scored 1.96. (4) After a narcotic was used once, the leftovers were wasted by 89.7% of the dental hygienists and 70.0% of the nurse aids. More dental hygienists wasted them(P<0.05). (5) For hand washing, antibiotic liquid soap was used by 19.3% of the dental hygienists and 10.0% of the nurse aids, which were both very low percentage. And just 37.2% of the dental hygienists utilized a disposable paper towel to dry their hands, and only 36.0% of the nurse aids used the same(P<0.05).

• Pediatric Infection and Vaccine
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• v.14 no.2
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• pp.162-170
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• 2007

Purpose : While cases of vancomycin-resistant enterococci (VRE) have increasingly been reported worldwide since it was first reported in the late 1980s, there have been few systemic studies on the pediatric population. The purpose of this study is to contribute to the planning of VRE prevention by investigating the prevalence, risk factors and transmission of VRE infection. Methods : We studied 230 patients under age 15 years who were isolated VRE between January 2001 and December 2006 retrospectively. The patients were classified into the intensive care unit (ICU) and the non-ICU groups. We reviewed the procedures before VRE detection as well as antibiotic sensitivity of detected organisms. Results : The number of VRE-isolation cases was higher in the ICU group than the non-ICU group. Instances of VRE-isolation were also more prevalent in patients who underwent operations or active procedures while taking 3rd-generation cephalosporins or glycopeptides. Almost all antibiotics except tetracycline were resistant to VRE. The proportion of 3rd-generation cephalosporin use was higher than those of any other antibiotics before VRE detection. Additionally, the use of 3rd-generation cephalosporins has increased annually, but that of glycopeptides had decreased in 2006. Also, the rates of VRE isolation have been increasing since 1998. Conclusion : VRE infection is increasing in pediatric population. Strict adherence to appropriate infection control guidelines for the prevention of VRE transmission in hospitals, and tracking of VRE colonization through active surveillance in high risk units are recommended.

• Korean Journal of Agricultural Science
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• v.25 no.1
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• pp.52-67
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• 1998

The investigative research on the mammalian milk purely consisted of the physiological quality of lactoferrin was conducted to reveal the antimicrobial ativity of specifically functional foods with antibiotic characteristics as a basic data in food manufacturing. Bovine lactoferrin were isolated from raw milk samples, and was digested with pepsin, trypsin and chymotrypsin. It was necessary then to separate and purify lactoferrin from bovine raw milk, and in order to analyze the antimicrobial activity of the enzyme-treated bovine lactoferrin in their required quantitative fraction. Afterwards Escherichia coli and Staphylococcus aureus was incubated in it. It was that investigated to enzyme-treated fractions molecular weight and the peptide fragment with antimicrobial effect. 1. The purity of enzyme-treated bovine lactoferrin(BLF) was tested by SDS-PAGE. As a results of 12% SDS-PAGE assay, pepsin-treated LF did not exhibited band until if reaches 14 KDa, while trypsin and chymotrypsin treated LF, known to contain the non-digestive lactoferrin exhibited band at a molecular weight of 33 KDa. 2. Bovine lactoferrin was sucessfully purified through the use of Sephadex G-50 Column. In order to assay LF through the Sephadex G-50 column chromatography, the digestive bovine lactoferrin (BLFs) was eluted with a linear gradient of 0.05% Tris-HCl. When the gel-filtration analysis, pepsin, trypsin and chymotrypsin treatments of BLF fragments was showed 2, 3, and 2 peak, respectively. The results of the HPLC analysis confirmed that had a non-digestive lactoferrin receptor, and trypsin and chymotrypsin treated BLFs has an antimicrobial effect. 3. To measure the strength of the antimicrobial effect of enzyme treated lactoferrin it was compared to the antimicrobial activity taking place at the incubated Escherichia coli and Staphylococcus aureus. This might explain the resistance of the microorganisms for peptide fragment. The pepsin-treated of bovine lactoferrin was markedly reduced by incubation of the cells. Trypsin-treated of BLF was similar to chymotrypsin-treated of BLF. However, trypsin and chymotrypsin treatments of BLFs were showed the antimicrobial effect until eight hours incubation for native bovine lactoferrin. Therefore the enzyme-treated lactoferrin have an antimicrobial effect even non-digestive lactoferrin. 4. The digestive bovine lactoferrin fragments assay was carried out by the use of Sephadex G-50 column chromatography and SDS-PAGE. The pepsin and chymotrypsin-treated fragments has a low molecular weight and trypsin-treated lactoferrin was only showed a band. It was described that characteristics of digestive protein. It appeared that there may be a relation between virulence and resistance to enzyme-treated BLF.