• Korean Journal of Microbiology
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• v.29 no.3
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• pp.184-188
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• 1991

Three strains of Clostridium thermocellum, JH01, JH20 and JH30 which are capable of producing ethanol directly from cellulose were isolated from composts. The morphological, cultural and physiological properties of the strains were similar to the ATCC type strain, except for carbon source utilization and degree of ethanol tolerance. All of the three isolates could use glucose and maltose as a sole carbon source and two of them, strains of JH01 and JH20 were three times more tolerant to ethanol than the ATCC type strain. Cellulases secreted by the isolated strains had higher activities than those of the ATCC type strain.

• The Plant Pathology Journal
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• v.31 no.3
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• pp.316-321
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• 2015

A small cationic peptide (JH8944) was tested for activity against a number of pathogens of agricultural crops. JH8944 inhibited conidium growth in most of the tested plant pathogens with a dose of $50{\mu}g/ml$, although one isolate of Fusarium oxysporum was inhibited at $5{\mu}g/ml$ of JH8944. Most conidia of Fusarium graminearum were killed within 6 hours of treatment with $50{\mu}g/ml$ of JH8944. Germinating F. graminearum conidia required $238{\mu}g/ml$ of JH8944 for 90% growth inhibition. The peptide did not cause any damage to tissues surrounding maize leaf punctures when tested at a higher concentration of $250{\mu}g/ml$ even after 3 days. Liposomes consisting of phosphatidylglycerol were susceptible to leakage after treatment with 25 and $50{\mu}g/ml$ of JH8944. These experiments suggest this peptide destroys fungal membrane integrity and could be utilized for control of crop fungal pathogens.

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.570-575
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• 2004

Three different strains of carotenoid accumulating XantlwphyUomyces dendrorhous mutants, JH1, JH2, and JH3, were isolated by NTG (N-methyl-N'-nitro-N-nitrosoguanidine) mutagenesis, which might potentially be useful for animal feed as well as for studies on the regulation and biosynthesis of astaxanthin. Mutants were selected based on the capability of growth and carotenoid production on the YM agar plate containing chemical inhibitor, $\beta$-ionone. Astaxanthin-overproducing mutant JH1 produced 4.032 mg astaxanthinlg dry cell weight, and this value was about 15-folds higher than that of wild-type. $\beta$-Carotene-overproducing mutant JH2 produced 0.273 mg $\beta$-carotene/g dry cell weight, and this was 4-folds increase from that of wild-type. In contrast, JH3 was a white-colored mutant that was unable to produce carotenoid pigment.

• Mycobiology
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• v.45 no.4
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• pp.370-378
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• 2017

Cylindrocarpon destructans is an ascomycete soil-borne pathogen that causes ginseng root rot. To identify effective biocontrol agents, we isolated several bacteria from ginseng cultivation soil and evaluated their antifungal activity. Among the isolated bacteria, one isolate (named JH7) was selected for its high antibiotic activity and was further examined for antagonism against fungal pathogens. Strain JH7 was identified as a Chromobacterium sp. using phylogenetic analysis based on 16S rRNA gene sequences. This strain was shown to produce antimicrobial molecules, including chitinases and proteases, but not cellulases. Additionally, the ability of JH7 to produce siderophore and solubilize insoluble phosphate supports its antagonistic and beneficial traits for plant growth. The JH7 strain suppressed the conidiation, conidial germination, and chlamydospore formation of C. destructans. Furthermore, the JH7 strain inhibited other plant pathogenic fungi. Thus, it provides a basis for developing a biocontrol agent for ginseng cultivation.

• Korean Journal of Microbiology
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• v.22 no.4
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• pp.257-263
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• 1984

A strain producing an extracellular cytosine deaminase was isolated from soil samples. The enzyme obtained from the strain possessed the substrate specificity to both cytosine and 5-fluorocytosine. From the results of its morphological, cultural, physiological, and biochemical properties, the strain was thought to be the genus Arthrobacter. Therefore, it was named as Arthrobacter sp. JH-13. The composition of optimum medium for the enzyme formation was 0.5% of peptone, 0.5% of meat extract, 0.5% of soluble starch, and 0.1% of KCl. The optimum pH for the enzyme formation was 8.0. When the microoganism was cultured aerobically in the above medium, enzyme production reached at maximum in 54 hours at $30^{\circ}C$.

• International Journal of Industrial Entomology and Biomaterials
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• v.45 no.2
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• pp.126-130
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• 2022

The silkworm is a food material that can simultaneously ingest phytochemicals from mulberry leaves, proteins with essential amino acids, and fatty acids. They are known to have hypoglycemic properties; however, further functional investigation is needed. In this study, four varieties of 3^rd day of fifth instar silkworm with different cocoon colors, namely Baegokjam (BG), Goldensilk (GS), Yeonnokjam (YN), and Juhwangjam (JH), were compared in terms of antioxidant properties and cholesterol-lowering effect. JH, which had the highest polyphenol content (+38% vs. GS, p<0.05) showed high antioxidant efficacy. Treatment with JH also resulted in the lowest cholesterol biosynthesis enzyme activity (28% vs. control, p<0.05). In the animal study, high-fat diet (HFD)-fed mice that were orally administered JH extract for 12 weeks showed lower body weight gain (-10.4% vs. HFD, p<0.05) and serum total cholesterol levels (-12.7% vs. HFD, p<0.05). Comparing the varieties, JH had the highest effect. In future studies, analysis of the active ingredients according to their variety should be done.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.11
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• pp.1222-1227
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• 2006

In this study, nine strains were isolated from heavy metal-contaminated soil in a mine. The high efficiency bacteria, JH1, to be able removal cadmium and copper, was selected by the screen test. JH1 was identified as Ralstonia eutropha by 16S rDNA analysis, fatty acid analysis, and its morphological and biochemical characteristics. After the cadmium-contaminated soil was washed with citric acid solution(pH 6, 10 mM), Ralstonia eutropha JH1 was inoculated in the soil washing water. In order to determine the optimal cell concentration for inoculation, cell concentrations were considered in 0.5, 1.0, 2.0, 4.0 g/L, respectively. The removal efficiencies for cadmium in each cell concentration of Ralstonia eutropha JH1 were 49.9, 84.4, 89.7% and 89.9% of 110 mg/L(Cd), after 5 days culture in soil washing water. When Ralstonia eutropha JH1 was inoculated in soil washing water containing each cadmium(110 mg/L) and copper(100 mg/L), each of them was removed completely during 6 days culture. The completely removing time for cadmium and copper in each low concentration, 10, 30 and 60 mg/L were 12, 18 and 48 hrs, respectively.

• Korean journal of applied entomology
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• v.31 no.2
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• pp.144-152
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• 1992

The juvenile hormone(JH) titers and juvenile hormone esterase (JHE) activities were mea¬sured in larval homogenates of the chestnut gall waL,J, Dryocosmus kuriphilus Yasumatsu, parasiting a susceptible and two resistant chestnut ( Cheuk-Pa, and Dan- Tak) varieties by GLC, Galleria wax test and Liquid scintilation counter. JH of the chestnut gall wasp was identified as JH- I. Their juvenile hormone titers were 35,800 GU/g(Cheuk-Pa), 30,900 GU/g (Dan-Tak), and 28,600 GU/g(susceptible variety). The juvenile hormone esterase activities were 1.48 n mole/min/ml(Cheuk-Pa), 1.63 n mole/min/ml(Dan- Tak), and 1.89 n mole/mini ml(susceptible variety). JH titer activity of the chestnut gall wasp parasiting resistant varie¬ties were higher than that from susceptible, whereas their JHE activity was higher in those from susceptible variety than those from resitant varieties. JH titer and JH specific esterase activity was inversely proportional.

• The Journal of Internal Korean Medicine
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• v.26 no.2
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• pp.341-352
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• 2005

Objectives: This study was carried out to investigate the effects of Jecksodoodangkuisan(JD) and Jecksodoodangkuisankahyunjicho(JH) against Colonic Mucosal Ulcer induced by indomethacin in mouse. Methods: The normal group consisted of mice that were not inflammation-induced. The control group was untreated gastro-inflammation-elicited mice. The sample group mice were those administered BO, JD and JH after gastro-inflammation elicitation. Results: In the immunohistochemical change, the distribution of COX-1 in mice treated with BO, JD and JH noticeably increased than control group(P<0.05). The distributions of $NF-{\kappa}B$, p50, COX-2, ICAM-1, HSP70 and Substance P in mice treated with BO, JD and JH noticeably decreased more than control group(P<0.05). And JH was most effective treatment against Colonic Mucosal Ulcer in the immunohistochemical change. Conclusions: According to the above results, Jecksodoodangkuisan and Jeckmdoodangkuisankahyunjicho are applicable treatments for Colonic Mucosal Ulcer.

• English Language & Literature Teaching
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• v.15 no.4
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• pp.75-94
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• 2009

This study was designed to assess demotivation factors and compare the factor between two secondary school student groups. It furthermore examined how the factors related to students' L2 proficiency. A 31-item questionnaire was completed by 407 junior (JH) and senior high school (SH) students. Five factors were extracted through the principal axis factoring: Teachers' competence and teaching styles, Dissatisfaction with English classes and grading system, Difficulty of learning English, Lack of motivation and interest in learning English, and Inadequate learning contents. Although both JH and SH students did not perceive their English teacher as a strong attribution of demotivation, Difficulty of learning English and Dissatisfaction with English classes and grading system were the two strongest demotivating factors. When compared the overall mean scores of each factor between JH and SH groups, significant differences were found in all factors except Factor 4, with SH students reporting stronger demotivation. JH students attributed their demotivation to Difficulty of learning English, while SH students attributed that to Dissatisfaction with English classes and grading system. Both groups tended to attribute their demotivation to external forces. The study also showed that several demotivation factors related negatively to L2 proficiency.