• Title/Summary/Keyword: Clear zone

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Flora of the Five West Sea Islands in Korea (서해 5도의 식물상)

  • Son, Dong Chan;Kim, Hyun-Jun;Lee, Dong-Hyuk;Jung, Su Young;Park, Soo Hyun;Chang, Kae Sun
    • Korean Journal of Plant Resources
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    • v.29 no.4
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    • pp.434-466
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    • 2016
  • In order to illustrate the flora of vascular plants distributed in the Five West Sea Islands, the authors collected vascular plants intensively in Baengnyeongdo and Socheongdo from May 2015 to August 2015. Also, voucher specimens from the previous investigations (Daecheongdo, Yeonpyeongdo and Soyeonpyeongdo) deposited at the Korean National Arboretum (KH) were re-identified. All of them were comprised of 108 families, 420 genera, 728 species, 6 subspecies, 86 varieties and 14 forms, totally 834 taxa. There were 8 endemic taxa, 19 rare taxa, 27 taxa for floristically specific to Korean floral zone except the species of their 1st and 2nd degree, and 107 naturalized taxa among the collected plants. Owing to their unusual phytogeography and low number of populations, the taxa Rosa maximowicziana Regel, Allium anisopodium Ledeb., Bistorta pacifica (Petrov ex Kom.) Kom., Scorzonera austriaca subsp. glabra (Rupr.) Lipsch. & Krasch. ex Lipsch., Iris dichotoma Pall., Amsonia elliptica (Thunb.) Roem. & Schult. were considered the most important. Based on these results, it is clear that appropriate plants to conserve the natural habitat of the Five West Sea Islands must be made immediately.

Eine Structure of the Pineal Body of the Snapping Turtle (자라 송과체의 미세구조)

  • Choi, Jae-Kwon;Oh, Chang-Seok;Seol, Dong-Eun;Park, Sung-Sik;Cho, Young-Kook
    • Applied Microscopy
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    • v.25 no.2
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    • pp.39-52
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    • 1995
  • Pinealocytes in the lower vertebrate are known to have photoreceptive function. These photoreceptor cells have been characterized morphologically in various species of lower vertebrates. No such ultrastructural studies, however, were reported in fresh water turtle. The purpose of this study is to characterize the pinealocytes and the phylogenetic evoluton of these cells is discussed in terms of functional analogy. I. Light microscopy: The pineal body was divided into incomplete lobules by connective tissue septa containing blood vessels, and parenchymal cells were arranged as irregular cords or follicular pattern. In the lobules, glandular lumina were present and contained often densely stained materials. II. Electron microscopy: The pineal parenchyma had three categories of cells: photoreceptor cells, supportive cells and nerve cells. The photoreceptor cells had darker cytoplasm compared to the supportive cells, and the enlarged apical cytoplasm(inner segment) containing abundant mitochondria and dense cored vescles protruded into the glandular lumen in which lamellar membrane stacks(outer segment), dense membranous materials, and cilia were present. Some of these lamellated membrane stacks appeared to be dege-nerating while others were apparently newly formed. Constricted neck portion of the photoreceptor cells contained longitudinally arranged abundant microtubules. centrioles and cross-striated rootlets. Cell body had well developed Golgi apparatus, abundant mitochondria, dense granules($0.5{\sim}1{\mu}m$), dense cored vesicles($70{\sim}100nm$), and rough endoplasmic reticulum occasionally with dense material within its cisterna. Basal portion of the photoreceptor cells had basal processes often with synaptic ribbons, which terminate in the complicated zone of cellular and neuronal processes. Synatpic ribbons often made contact with the nerve processes and the cell processes of neighboring cells. In some instances, these ribbons were noted free within the basal process and were also present at the basal cell mem-brane facing the basal lamina. Obvious nerve endings with clear and dense cored vesicles were observed among the parenchymal cells. Photoreceptor cells of the snapping turtle pineal body were generally similar in fine structure to those of other lower verterbrates reported previously, and suggested to have both photoreceptive and secretory functions which were modulated by pinealofugal and pinealopedal nerves. The supportive cells were characterized by having large dense granules($0.3{\sim}1{\mu}m$), abundant ribosomes, well developed Golgi apparatus and rough endoplasmic reticulum. These cells were furnished with microvilli on the luminal cell surfaces, and often had centrioles, striated rootlets, abundant filaments especially around the nucleus, and scattered microtubules. Some supportive cells had cell body close to the lumen and extended a long process reaching to basal lamina, which appeared to be a glial cell. Nerve cells within the parenchyma were difficult to identify, but some large cells located basally were suspected to be nerve cells, since they had synaptic ribbon contact with photoreceptor cells.

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Antimicrobial Activity of Garlic Extracts according to Different Cooking Methods (조리방법을 달리한 마늘 추출물의 항균활성)

  • Kim Yong Doo;Kim Ki Man;Hur Chang Ki;Kim Eun Sun;Cho In Kyung;Kim Kyung Je
    • Food Science and Preservation
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    • v.11 no.3
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    • pp.400-404
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    • 2004
  • This study was conducted to find the antimicrobial activity of garlic extracts by various processing methods(boiled, pan fried, microwave heated, pickled). Ethanol and water extracts from garlic sample were prepared and antimicrobial activities were determined against 10 microoganisms ; food borne pathogens, food poisoning microoganisms, food-related bacteria and yeasts. The ethanol extracts from the fresh and pickled garlic showed antimicrobial activities for test microoganisms, except lactic acid bacteria and yeast. However, the antimicrobial activities were decreased by heat treatment. The minimum inhibitory concentration(MIC) of the fresh garlic extracts was determined to 0.1 mg/mL against an gram positive bacterium and 0.5 mg/mL against an gram negative bacterium. The antimicrobial activities of the ethanol extracts were affected by heating methods and not by pHs.

Antimicrobial Activity against Helicobacter pylori and Antioxidant Activity of Yerusalem sage (Phlomis frutcosa L.) (예루살렘세이지(Phlomis frutcosa L.) 추출물의 Helicobacter pylori에 대한 항균활성과 항산화활성)

  • Kim, Jeung-Hoan;Yoon, So-Jeung;Cho, Young-Je
    • Applied Biological Chemistry
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    • v.48 no.2
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    • pp.178-182
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    • 2005
  • The concentration of total phenolic compounds of the water and ethanol extracts of Yerusalem sage were 9.4 mg/g and 11.1 mg/g respectively. The total antioxidant activities of water and ethanol extracts of Yerusalem sage were 96.8% and 91.4% in ABTS assay and 97.6% and 87.2% in DPPH assay, PF of the water and ethanolic extracts were 1.1 and 1.6, respectively. TBARS were $0.9{\times}10^{-3}\;{\mu}M$ and $0.3{\times}10^{-3}\;{\mu}M$, respectively. Antimicrobial effect against H. pylori of the ethanol extract was $9{\sim}15\;mm$ of clear zone diameter at $50\;{\mu}g/ml{\sim}200\;{\mu}g/ml$ of phenolic compound. Phenolic profiles in Yerusalem sage chlorogenic aicd was the highest both in water and ethanol extracts in HPLC analyses.

Isolation and Identification of Lactic acid Producing Bacteria from Kimchi and Their Fermentation Properties of Soymilk (젖산 생성능이 우수한 김치 유래 젖산균의 분리 및 두유 발효 특성)

  • Lee, Lan-Sook;Jung, Kyung Hee;Choi, Ung-Kyu;Cho, Chang-Won;Kim, Kyung-Im;Kim, Young-Chan
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.11
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    • pp.1872-1877
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    • 2013
  • Lactic acid bacteria were selected on the basis of lactic acid producing ability from kimchi, a traditional Korean fermented food. Among the initial screening of over 150 strains selected from the sample, 27 strains were selected as lactic acid producing bacteria, and 4 strains were finally selected based on their ability to produce relatively high levels of lactic acid. The four strains were identified as Lactobacillus (L.) plantarum Gk04, Pediococcus pentosaceus Gk07, L. brevis Gk35 and L. curvatus Gk36 by the conventional morphological, cultural, physiological and biochemical characteristics, as well as by 16S rRNA sequence analysis. Among the identified lactic acid bacteria, L. curvatus Gk36 was used for soymilk fermentation. The viable cell counts and acidity values measured for the L. curvatus Gk36 were comparable to the commmercial L. acidopillus. Thus, the L. curvatus Gk36 is a potential probiotic strain to prepare fermented soy products, such as kephir, yogurt, tempeh and soy sauce.

Effect of Pine Needle and Green Tea Extracts on the Survival of Pathogenic Bacteria (솔잎과 녹차 추출물이 식중독세균의 생존에 미치는 영향)

  • 박찬성
    • Korean journal of food and cookery science
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    • v.16 no.1
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    • pp.40-46
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    • 2000
  • The sensitivity of various pathogenic bacteria(Listeria monocytogenes, Staphylococcus aureus, Aeromonas hydrophila, Escherichia coli O157:H7 and Salmonella typhimurium) to the pine needle and green tea extracts was tested. Water extract of pine needle(PNW), 70% ethanol extract of pine needle(PNE), water extract of green tea(GTW) and 70% ethanol extract of green tea(GTE) were prepared for the test of antibacterial activty. Tryptic soy broth(TSB) containing 0∼2%(w/v) of pine needle and green tea extracts were inoculated with 10$\^$5/∼10$\^$6/ cells/ml of each bacterium and incubated at 35$\^{C}$ for 24 hours. The standard plate count method was used to measure the inhibitory effect of the extracts. Minimum inhibitory concentration(MIC) and minimum bactericidal concentration(MBC) were derived from the survival curves of pathogenic bacteria. Antibacterial activities of the pine needle and green tea extracts were compared with that of sodium benzoate, a preservative, by clear zone test. L. monocytogenes, S. aureus and A. hydrophila were completely inhibited at 0.4∼1.6% level while E. coli and S. typhimurium were very resistant to the pine needle extracts. Green tea extracts completely inhibited all strains tested at 0.2∼1.0% level and bactercidal to all strains except L. monocytogenes at 0.5∼2.0% level. Antibacterial activities of pine needle and green tea extracts were stronger than that of sodium benzoate. The order of antibacterial activities of pine needle and green tea extracts to the pathogenic bacteria was GTE > GTW > PNE > PNW. This result suggests that green tea extracts can be used as an effective natural antibacterial agent in food.

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Analysis of Antibacterial, Antioxidant, and In Vitro Methane Mitigation Activities of Fermented Scutellaria baicalensis Georgi Extract (발효 황금 뿌리 추출물의 항균, 항산화 효과 및 메탄가스 저감 효과 In Vitro)

  • Marbun, Tabita Dameria;Song, Jaeyong;Lee, Kihwan;Kim, Su Yeon;Kang, Juhui;Lee, Sang Moo;Choi, Young Min;Cho, Sangbuem;Bae, Guiseck;Chang, Moon Baek;Kim, Eun Joong
    • Korean Journal of Organic Agriculture
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    • v.24 no.4
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    • pp.735-746
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    • 2016
  • This study was conducted to investigate the antibacterial, antioxidant, and in vitro greenhouse gas mitigation activities of fermented Scutellaria baicalensis Georgi extract. Seven starter cultures were used, comprising four of lactic acid bacteria and three of Saccharomyces cerevisiae. Ten grams of S. baicalensis Georgi powder was diluted in 90 mL autoclaved MRS broth. Each seed culture was inoculated with 3-10% (v/v) S. baicalensis Georgi MRS broth and incubated at $30^{\circ}C$ for 48 h. Among the starter cultures used, only Lactobacillus plantarum EJ43 could withstand the fermentation conditions. This fermentation broth was dried and extracted with ethanol to assess its antibacterial, antioxidant, and in vitro methane mitigation activities. The extract of S. baicalensis Georgi fermented by L. plantarum EJ43 (SBLp) showed higher antibacterial activity (bigger clear zone) compared to the unfermented S. baicalensis Georgi extract (SB0). SBLp also presented 1.2 folds higher antioxidant activity than SB0. During in vitro rumen fermentation, SBLp showed reduction in methane production compared to SB0 or the control. In conclusion, fermentation by L. plantarum EJ43 may enhance antibacterial and antioxidant activities of S. baicalensis Georgi and decrease enteric methane production.

Comparative Efficacy for Dressing Methods of Iodine on Infected Full Thickness Skin Wound in the Mouse (흰 쥐의 감염된 전층피부 결손에서 Iodine의 드레싱 방법에 따른 창상치유 효과의 비교)

  • Lee, Jong-Hoon;Kim, Yo-Han;Min, Kyung-Hee;Hong, Sung-Hee;Lee, Won-Mi;Chae, Jeong-Don;Jun, Jin-Hyun
    • Archives of Plastic Surgery
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    • v.37 no.3
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    • pp.213-219
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    • 2010
  • Purpose: Iodine has been used for the prevention or management of wound infection as a topical agent. Although iodine was widely used mainly by Betadine$^{(R)}$ and cadexomer iodine, there was no comparative study on the efficacies of dressing methods of iodine. And also it's wound healing effect was not yet clear. The purpose of this study is to compare antibacterial effects and wound healing effects associated with various dressing methods of iodine on infected full thickness skin defect in the mouse. Methods: One full thickness skin defects in the mice (n=60) were developed on the back and left open for twenty-four hours. Sixty mice were divided into four groups : group S (dressing with Betadine$^{(R)}$ soaking, n=15), group T (dressing with Betadine$^{(R)}$ topping, n=15), group I (dressing with Iodosorb$^{(R)}$, n=15), group G (control group, dressing with dry gauze, n=15). The size of the wound defects and the grades of wound healing were evaluated in 4, 7, 10 days, and antibacterial effect was evaluated with restricted zone in Mueller Hinton agar by disk diffusion method. Results: After the wound was left open for twenty-four hours, many Staphylococcus aureus were cultured. The wound defect size was decreased in order of Betadine$^{(R)}$ soaking, Iodosorb$^{(R)}$, Betadine$^{(R)}$ topping and gauze dressing group in all days, but difference among experimental groups was not statistically significant. The grade score of wound healing was increased in order of Betadine$^{(R)}$ soaking, Iodosorb$^{(R)}$, Betadine$^{(R)}$ topping and gauze dressing group, and the difference was statistically significant. Antibacterial effect for S. aureus was increased in order of Iodosorb$^{(R)}$, Betadine$^{(R)}$ soaking, Betadine$^{(R)}$ topping and gauze dressing group, and the difference was statistically significant. Conclusion: Selection of the effective dressing method of iodine for infected wounds remains a controversial decision. According to this study, Iodosorb$^{(R)}$ may be most effective method for antibacterial effect and Betadine$^{(R)}$ soaking may be most effective method for infected wound healing. However, further study is necessary to evaluate the clinical efficacy of dressing methods of iodine and to search for the mechanisms that explain their effects.

Isolation of Pseudoxanthomonas sp. W12 and WD32 Producing Extracellular Protease (단백질분해효소를 생산하는 Pseudoxanthomonas sp. WD12와 WD32의 분리)

  • Cho, Woon-Dong;Lee, Je-Kwan;Lim, Chae-Sung;Park, A-Rum;Oh, Yong-Sik;Roh, Dong-Hyun
    • Korean Journal of Microbiology
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    • v.46 no.1
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    • pp.63-67
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    • 2010
  • Proteases catalyze hydrolytic cleavage of a peptide bond between amino acids and occupy pivotal positions in application in physiological and commercial fields. During the screening for novel bacteria producing extracellular protease, two bacterial strains, WD12 and WD32, were isolated from rotten trees and they made clear zone on LB plates supplemented with 1% skim milk. The similarities of 16S rRNA gene sequence of either WD12 or WD32 to GenBank database showed the highest to Pseuoxanthomonas mexicana as 97.8 and 99.8%, respectively. Phylogenetic analysis showed that both isolated was located within the cluster comprising P. mexicana and P. japonesis. WD12 and WD32 were catalase- and oxidase-positive, Gram-negative rod strains. In case of WD12, it could assimilate malate, but could not assimilate D-mannose, which were different characteristics from P. mexicana. Both Pseuoxanthomonas sp. WD12 and WD32 optimally produced extracellular protease at $35-37^{\circ}C$, and maximal activity showed as 656 unit/ml and 267 unit/ml, respectively.

Effects of alloy elements on electrochemical characteristics improvement of stainless steel in sea water (해수환경하에서 스테인리스강의 전기화학적 특성 개선을 위한 합금원소의 영향)

  • Lee, Jung-Hyung;Choi, Yong-Won;Jang, Seok-Ki;Kim, Seong-Jong
    • Journal of Advanced Marine Engineering and Technology
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    • v.38 no.7
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    • pp.890-899
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    • 2014
  • Austenitic stainless steel is widely used in various industries due to its excellent corrosion resistance. However, Cr carbides precipitation along the grain boundaries after heat treatment or welding may develop Cr depleted zone, which acts as a preferential site for intergranular corrosion attack. To resolve this, carbon stabilizing element such as Ti or Nb are added to suppress formation of Cr carbides. However, there are few reports on corrosion characteristics under seawater environment of the stabilized stainless steel. This study investigated the effects of alloying contents on the electrochemical characteristics in seawater of stainless steel containing stabilizing element(Ti and Nb). To achieve this, the changes on the microstructure due to alloying were observed with microscope, and the electrochemical characteristics were determined by measurement of natural potential and potentiodynamic polarization experiments. The microscopic observation revealed that all specimens had inclusions other than the austenite matrix phase due to the addition of alloying elements. Such inclusions are considered to have different electrochemical characteristics from those of the matrix, and thus a clear distinction was found according to the type of stabilizers and the contents. The results of this study suggest that it is important to consider the effects of alloying contents on the electrochemical characteristics in seawater with the addition of Ti or Nb into austenitic stainless steel.