• The Korean Journal of Pesticide Science
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• v.4 no.4
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• pp.66-71
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• 2000

Effect of temperature on resting spore germination of Plasmodioprora brassicae was indirectly estimated based on examining temporal change of number of inactive resting spores. Resting spore germination was the highest at $28^{\circ}C$ reaching 55.6% and 82.5%, 24hr and 132hr after treatment, respectively. Optimum pH for resting spore germination was pH6, following pH7 and pH8, and the germination was inhibited at pH 4, and pH9. termination of resting spores was stimulated by root extracts of radish, Chinese cabbage and kidney bean, but inhibited by that of lettuce. Number of inactive resting spores was increased as temperature increases and time prolongs after temperature treatment. However, degree of inactivation of resting spores after 1hr at $40{\sim}65^{\circ}C$ was similar with $40{\sim}60%$, but rapidly increased to 91.5% at $70^{\circ}C$. When root galls were submerged in water, density of inactive resting spores was increased rapidly and reached 60.3% 9 days after treatment. Flooding of infested soil resulted in 30% reduction of survived resting spores 5 months later. Among the two registered fungicides, fluazinam was better for inactivation of resting spores than flusulfamide, but both fungicides were inferior to phosphoric acid.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.1
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• pp.56-60
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• 1976

In order to find effective seed collection method from cultivated Porphyra, benthic diatom elimination, culturing conditions of Conchocelis, liberation of conchospores and treatment of the fronds to obtain monospores have been studied. Elimination of benthic diatoms from Porphyra fronds is successfully performed by careful brushing the fronds in sea water and freshwater alternatively. For the culturing of Conchocelis Schleiber's solution enriched with only soil extracts, vitamins and Fe-EDTA was satisfactory. Growth under 16 hours illumination is 1.29 times faster than those under 10 hours illumination. When the culturing water was airated the growth was $1.41\~l.50$ times faster than the growth in stagnant water. Total amount of conchospores liberated from Conchocelis which has been cultured under airation was much more than those of conchospores under stagnant condition. Effective liberation of monospores was observed in the fronds which have been dried in air for 6 hours $(21.23\~24.19\%\;water\;content)$.

• Journal of Life Science
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• v.20 no.2
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• pp.269-274
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• 2010

An antifungal antibiotic-producing strain, BCNU 2003, was isolated from forest soil in Korea. The morphological and physiological characters, and 16S rRNA sequences analysis of strain BCNU 2003 identified this strain as Bacillus genus. The Bacillus sp. BCNU 2003 showed strong antifungal activities against Aspergillus niger, Trichophyton mentagrophytes and Trichophyton rubrum with inhibition ranging from 62.05 to 63.49% by using dual culture technique. Bacillus sp. BCNU 2003 produced a maximum level of antifungal substances under aerobic incubation at 28oC and pH 6.5-7.2 for 6 days in LB broth. Ethyl acetate extract of the cultured broth showed strong antifungal activity and a broad antifungal spectrum against various pathogenic fungi. The minimum inhibitory concentration (MIC) values for its active extracts ranged between 0.0625 mg/ml and 1 mg/ml. In addition, Bacillus sp. BCNU 2003 was determined to have the ability to produce enzymes such as amylase, protease, gelatinase and catalase.

• Journal of Families and Better Life
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• v.28 no.5
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• pp.25-38
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• 2010

The purpose of this study was to investigate the trend changes of the health characteristics and the elements of Han-Ok appeared in the articles of the daily newspaper, and to provide basic information for applying to the healthy housing for the public living in modern society and furthermore the various facilities for healing. For the study, the relevant articles of 4 daily newspapers published from 1st of January in 1960 to 28th of February in 2010 were collected and analyzed. The results of the study were as follows: First, the articles about the health characteristics and the elements of Han-Ok have rapidly grown since the year of 2000. Especially, the residents' interviews, case reports and actual living condition of Han-Ok recently tend to increase. Second, the health characteristics of Han-Ok in the recent articles were focused more on the mental and social health than on the physical health. The physical health had the characteristics of the block of hazard environments, the offer of good quality environments, and the enhancements of residents' health. The mental health consisted of the psychological comfort, the sensory satisfaction and the emotional growth. There have been improvements of family relationships and the interactions with neighbors in the characteristics of social health since 2000. Third, the health elements of Han-Ok in terms of architecture and interior design were the structure, space, material, doors & windows, furniture & props, nature, and villages. The material elements were more stressed before 2000, but the spaces and the nature elements were highly focused after 2000 and the structure elements were steadily high regardless of years. Fourth, of the health elements, the structure and the material had the high effects on the physical health characteristics, on the other hand the spaces and the nature influenced more on the mental health. On-dol, Ma-dang, Dae-cheong, Ma-ru, soil, wood, Changhoji, natural environments, and doors & windows were the detail health elements which had high effects on the health characteristics of Han-Ok. For the future study, the experience based in-depth studies of the residents living in Han-Ok are suggested to grasp the actual effects of Han-Ok on the health. The professional consultations are also needed for the extracts of the health characteristics of Han-Ok and the functional elements which can be applied to the modern buildings.

• Journal of Microbiology and Biotechnology
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• v.26 no.12
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• pp.2159-2170
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• 2016

Many plant-pathogenic bacteria are dependent on quorum sensing (QS) to evoke disease. In this study, the population of QS and quorum quenching (QQ) bacteria was analyzed in a consecutive monoculture system of Pseudostellaria heterophylla. The isolated QS strains were identified as Serratia marcescens with SwrIR-type QS system and exhibited a significant increase over the years of monoculture. Only one QQ strain was isolated from newly planted soil sample and was identified as Bacillus thuringiensis, which secreted lactonase to degrade QS signal molecules. Inoculation of S. marcescens to P. heterophylla root could rapidly cause wilt disease, which was alleviated by B. thuringiensis. Furthermore, the expression of lactonase encoded by the aiiA gene in S. marcescens resulted in reduction of its pathogenicity, implying that the toxic effect of S. marcescens on the seedlings was QS-regulated. Meanwhile, excess lactonase in S. marcescens led to reduction in antibacterial substances, exoenzymes, and swarming motility, which might contribute to pathogensis on the seedlings. Root exudates and root tuber extracts of P. heterophylla significantly promoted the growth of S. marcescens, whereas a slight increase of B. thuringiensis was observed in both samples. These results demonstrated that QS-regulated behaviors in S. marcescens mediated by root exudates played an important role in replanting diseases of P. heterophylla.

• The Korean Journal of Food And Nutrition
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• v.15 no.3
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• pp.257-266
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• 2002

The purpose of this study is screening of microfloras involved in hydrolysis of seaweed tenella, seaweed fusiforme and green laver. This is a part of studies on the hydrolysis of seaweed using microorganisms. First, about two hundred microflora samples were obtained from mountain, rice field, dry field, sea, seaside and fish market in the vicinity of Yeosu. Thirty-three microflora samples were screened from the destruction of tissue in sea tangle and sea mustard. It was sufficient that results of the naked eye observation were obtained at eight microflora samples as a feces of bull, a decayed pine tree, a soil of dry field, the mud of the banks in a rice field, the water of a ditch in a rice field, the weed of the banks in a rice field, the water in a rice field and leaved in the air. Above all, extraction rate and contents of reducing sugar in extracts of seaweeds added a decayed pine tree(sample No. 8) and the water of a ditch in a rice field(sample No. 27) were showed high value. And the value of chemical analysis of the sample is much better in comparison with control. Accordingly the hydrolysis of seaweed using microorganisms in the inside of these microflora samples can be possible.

• The Plant Pathology Journal
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• v.33 no.4
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• pp.393-401
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• 2017

Efforts to control viral diseases in crop production include several types of physical or chemical treatments; antiviral extracts of a number of plants have also been examined to inhibit plant viral infection. However, treatments utilizing naturally selected microorganisms with activity against plant viruses are poorly documented. Here we report isolation of a soil inhabiting bacterium, Pseudomonas oleovorans strain KBPF-004 (developmental code KNF2016) which showed antiviral activity against mechanical transmission of tobamoviruses. Antiviral activity was also evaluated in seed transmission of two tobamoviruses, Pepper mild mottle virus (PMMoV) and Cucumber green mottle mosaic virus (CGMMV), by treatment of seed collected from infected pepper and watermelon, respectively. Pepper and watermelon seeds were treated with culture supernatant of P. oleovorans strain KBPF-004 or control strain ATCC 8062 before planting. Seeds germinated after treatment with water or ATCC 8062 yielded about 60% CGMMV or PMMoV positive plants, whereas < 20% of KBPF-004-treated seeds were virus-infected, a significantly reduced seed transmission rate. Furthermore, supernatant of P. oleovorans strain KBPF-004 remodeled aggregation of PMMoV 126 kDa protein and subcellular localization of movement protein in Nicotiana benthamiana, diminishing aggregation of the 126 kDa protein and essentially abolishing association of the movement protein with the microtubule network. In leaves agroinfiltrated with constructs expressing the coat protein (CP) of either PMMoV or CGMMV, less full-size CP was detected in the presence of supernatant of P. oleovorans strain KBPF-004. These changes may contribute to the antiviral effects of P. oleovorans strain KBPF-004.

• Weed & Turfgrass Science
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• v.5 no.4
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• pp.260-267
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• 2016

Amino acids in the plant were intermediate metabolites which produced by uptake and assimilation of nitrogen and these extracts which gained by bio-chemical digestion from protein of plant or animal were a source of functional fertilizer. This study was conducted to evaluate effects of keratin amino acid fertilizer (KAF) gained from animal hair or hoof on changes of turfgrass quality and growth by investigating turf color index, chlorophyll index, shoot number, clipping yield, and nutrient content in the turfgrass tissue. Treatments were designed as follows; non-fertilizer (NF), compound fertilizer (CF), keratin amino acid fertilizer treatments [CF + KAF $0.26ml\;m^{-2}$ (CKF), CF + KAF $0.52ml\;m^{-2}$ (2CKF)], and only keratin amino acid fertilizer treatment (KF). Shoot number, clipping yield, and nitrogen uptake of KF were higher than those of CF. As compared with CF, soil chemical properties, turf color index, chlorophyll index and clipping yield of keratin amino acid fertilizer were not significant, but shoot number and uptake of N and K were increased significantly. These results show that the application of keratin amino acid fertilizer increased shoot number and growth by increased uptake of nitrogen and potassium.

• Parasites, Hosts and Diseases
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• v.57 no.4
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• pp.341-357
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• 2019

Acanthamoeba, one of free-living amoebae (FLA), remains a high risk of direct contact with this protozoan parasite which is ubiquitous in nature and man-made environment. This pathogenic FLA can cause sight-threatening amoebic keratitis (AK) and fatal granulomatous amoebic encephalitis (GAE) though these cases may not commonly be reported in our clinical settings. Acanthamoeba has been detected from different environmental sources namely; soil, water, hotspring, swimming pool, air-conditioner, or contact lens storage cases. The identification of Acanthamoeba is based on morphological appearance and molecular techniques using PCR and DNA sequencing for clinico-epidemiological purposes. Recent treatments have long been ineffective against Acanthamoeba cyst, novel anti-Acanthamoeba agents have therefore been extensively investigated. There are efforts to utilize synthetic chemicals, lead compounds from medicinal plant extracts, and animal products to combat Acanthamoeba infection. Applied nanotechnology, an advanced technology, has shown to enhance the anti-Acanthamoeba activity in the encapsulated nanoparticles leading to new therapeutic options. This review attempts to provide an overview of the available data and studies on the occurrence of pathogenic Acanthamoeba among the Association of Southeast Asian Nations (ASEAN) members with the aim of identifying some potential contributing factors such as distribution, demographic profile of the patients, possible source of the parasite, mode of transmission and treatment. Further, this review attempts to provide future direction for prevention and control of the Acanthamoeba infection.

• Journal of Life Science
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• v.33 no.5
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• pp.414-421
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• 2023

Cnidium japonicum (C. japonicum) is a type of halophyte that inhabits soil of a high salinity, and according to previous studies, it is known to have antitumor effects. However, the skin's protective effect, particularly against UVB irradiation, has not been revealed. In this study, C. japonicum crude extract was studied to determine its effect on damage to human keratinocytes (HaCaT) induced by UVB irradiation, and ROS assays were performed, the results of which showed that C. japonicum crude extract affects UVB-induced photoaging damage in human keratinocytes. To examine inhibitory effects against the expressions of MMPs, RT-PCR and Western blot assay were performed by treating the crude extract at concentrations of 10, 50, and 100 ㎍/ml by irradiating UVB at 15 mJ/cm². As a result, it was confirmed that the mRNA and protein expression levels of MMP-1, MMP-3, and MMP-9 decreased in the group treated with C. japonicum crude extract, which also effectively regulated the antioxidant defense mechanism pathway by activating JNK, ERK, and p38. In conclusion, the current study suggested the possibility that C. japonicum could be used as a raw material for anti-photoaging cosmeceuticals in the future.