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Fluctuation of the sensitivity of Colletotrichum spp. causing the red-pepper anthracnose to chlorothalonil (살균제 chlorothalonil에 대한 고추 탄저병균의 감수성 변화)

  • Kim, Joon-Tae;Lee, Kyeong-Hee;Min, Ji-Young;Cho, In-Joon;Kang, Beum-Kwan;Park, Seong-Woo;Bach, Nguyen Van;Kim, Yun-Sik;Hong, Seong-Taek;Rho, Chang-Woo;Kim, Heung-Tae
    • The Korean Journal of Pesticide Science
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    • v.8 no.3
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    • pp.231-237
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    • 2004
  • Monitoring for the sensitivity of Colletotrichum spp. causing red-pepper anthracnose to chlorothalonil was conducted by the agar dilution method, which were isolated from infected pepper fruits in 1999 and 2002. Among the isolates in 1999 or 2002, their sensitivity to fungicide was fluctuated. Investigating the inhibitory effect of $500{\mu}g/m\ell$ of chlorothalonil on the mycelial growth of Colletotrichum isolates isolated from the infected red-pepper fruits in 1999, the frequency of isolates was 23.4%, which showed 100% of inhibitory effect on mycelial growth, and 29.7% showing below 60%. Isolates in 2002, however, showed 34.6% and 14.8% of inhibitory effect on PDAs including the same concentration of fungicide, respectively, These results showed that the sensitivity of Colletotrichum isolates in 1999 was inferior to that in 2002. According to the sampling region, isolation frequency among isolates in 2002 showing less MIC rather than 1999 was increased in Kyunggi, Kangwon, Kyungbuk and Kyungnam while the frequency of resistant isolates was done in Chungnam, Chungbuk, Cheonnam and Cheonbuk Fungicide monitoring results in this report will be of use on controlling the anthracnose in each region cultivating red-pepper.

Improvement in Antagonistic Ablility of Antagonistic Bacterium Bacillus sp. SH14 by Transfer of the Urease Gene. (Urease gene의 전이에 의한 길항세균 Bacillus sp. SH14의 길항능력 증가)

  • 최종규;김상달
    • Microbiology and Biotechnology Letters
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    • v.26 no.2
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    • pp.122-129
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    • 1998
  • It were reported that antifungal mechanism of Enterobacter cloacae is a volatile ammonia that produced by the strain in soil, and the production of ammonia is related to the bacterial urease activity. A powerful bacterium SH14 against soil-borne pathogen Fusarium solani, which cause root rot of many important crops, was selected from a ginseng pathogen suppressive soil. The strain SH14 was identified as Bacillus subtilis by cultural, biochemical, morphological method, and $API^{circledR}$ test. From several in vitro tests, the antifungal substance that is produced from B. subtilis SH14 was revealed as heat-stable and low-molecular weight antibiotic substance. In order to construct the multifunctional biocontrol agent, the urease gene of Bacillus pasteurii which can produce pathogenes-suppressive ammonia transferred into antifungal bacterium. First, a partial BamH I digestion fragment of plasmid pBU11 containing the alkalophilic B. pasteurii l1859 urease gene was inserted into the BamH I site of pEB203 and expressed in Escherichia coli JM109. The recombinant plasmid was designated as pGU366. The plasmid pGU366 containing urease gene was introduced into the B. subtilis SH14 with PEG-induced protoplast transformation (PIP) method. The urease gene was very stably expressed in the transformant of B. subtilis SH14. Also, the optimal conditions for transformation were established and the highest transformation frequency was obtained by treatment of lysozyme for 90 min, and then addition of 1.5 ${mu}g$/ml DNA and 40% PEG4000. From the in vitro antifungal test against F. solani, antifungal activity of B. subtilis SH14(pGu366) containing urease gene was much higher than that of the host strain. Genetical development of B. subtilis SH14 by transfer of urease gene can be responsible for enhanced biocontrol efficacy with its antibiotic action.

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Adsorption Characteristics of Heavy Metals on Clay Minerals (점토광물에 의한 중금속 흡착 특성)

  • Moon, Jeong-Ho;Kim, Tae-Jin;Choi, Choong-Ho;Kim, Cheol-Gyu
    • Journal of Korean Society of Environmental Engineers
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    • v.28 no.7
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    • pp.704-712
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    • 2006
  • This research was designed to investigate the removal of heavy metals, such as $Al^{3+}$, $Cu^{2+}$, $Mn^{2+}$, $Pb^{2+}$ and $Zn^{2+}$, by adsorption on clay minerals. Bentonite(Raw-Bentonite), $Ca^{2+}$ and $Na^+$ ion exchanged bentonite(Ca- and Na-Bentonite) and montmorillonite, such as KSF and K10 from Sigma Aldrich, were used as adsorbents. The component of five inorganic adsorbents was analyzed by XRF, and the concentration of metal ions was measured by ICP. The cation exchange capacity(CEC) and the particle charge of adsorbents were measured. The initial concentration range of metal ions was $10{\sim}100$ mg/L. From the experimental results, it was shown that the adsorption equilibrium was attained after $1{\sim}2$ hours. The maximum percentage removal of $Al^{3+}$, $Cu^{2+}$, $Pb^{2+}$ and $Zn^{2+}$ on Na-Bentonite were more than 98% and that of $Mn^{2+}$ was 66%. $Al^{3+}$ was leached out from KSF with the higher concentration of hydrogen ion. Percentage removals of $Pb^{2+}$ and $Zn^{2+}$ on KSF were 88% and 59%, respectively. In general, the percentage removal of metal ions was decreased with the higher initial concentration of metal ions. The adsorption capacity of metal ions on Na-Bentonite was $1.3{\sim}19$ mg/g. Freundlich equation was used to fit the acquired experimental data. As the results, the adsorption capacity of metal ions was in the order of Na-Bentonite$\gg$Raw-Bentonite$\cong$K10>Ca-Bentonite>KSF. Freundlich constant, K of Na-Bentonite was the largest for metal ions. The order K of Na-Bentonite was Al>Cu>Pb>Zn>Mn, and the adsorption intensity(1/n) was determined to be $0.2{\sim}0.39$.

Efficiency Estimation for Desalination System of Seawater Using Reverse Osmosis Membrane (역삼투압막 해수담수화 장치의 미네럴 분리 성능평가)

  • Moon, Deok-Soo;Jung, Dong-Ho;Kim, Hyeon-Ju;Shin, Phil-Kwon
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.8 no.2
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    • pp.60-66
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    • 2005
  • When external pressure higher than osmosis pressure is reversely derived into solution, its solvent is moved into the solution having lower concentration, which is called 'reverse osmosis'. We investigated the desalination application of deep ocean water using reverse osmosis pressure of $40-70\;kgf/cm^2$ We observed how to operational factor j like flow rate, water temperature and pressure have effect on efficiency of reverse osmosis membrane and salts rejection. Fluxes of reverse osmosis membrane are directly proportional to water temperature and pressure. However, salts rejection rates are positively correlated with pressure and inversely proportional to water temperature. Separation efficiencies of osmosis membrane for major elements such as $Mg^{2+},\;Ca^{+2},\;Na^+\;and\;K^+$ are as follows in a strong electrolysis solution like seawater; $Ca^{2+},\;Mg^{2+}>K^+>Na^+$. Rejection rates of $Mg^{2+}\;and\;Ca^{2+}$ that have high electric charges are over 99% and show positively correlation with water temperature. Rejection rates of $Na^+$ having low electric charge is observed to be 98%-99%, which rates is much lower than those of $2^+$ charged ions like $Ca^{2+}\;and\;Mg^{2+}$. Ion rejection rates of boron, B, are much low because boron is present il free state or gas phase in seawater. Boron concentration in desalination water is over criteria of Korean drinking water, 0.3 mg/L. However, we could satisfied with the criteria of drinking water under the operation condition like temperature $5^{\circ}C$ and pressure $70kgf/cm^2$, using the relationship that rejection rates of boron is proportional to pressure and is inversely proportional to water temperature

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Improvement of Physical Properties for Edible Films from Alaska Pollack Protein (명태 단백질로 제조한 가식성 필름의 물성 개선)

  • Mok Jong Soo;Song Ki Cheol;Kang Chang Su;Chang Soo Hyun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.4
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    • pp.417-423
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    • 2002
  • The edible films were prepared from the protein of alaska pollack, Theragra chalcogrmma. Effects of plasticizer, cross linker and laminated film on physical properties such as tensile strength (TS), elongation (E) and water vapor permeability (WVP) of films were investigated. In adding various kinds of plasticizers, TS of the films prepared with propylene glycol (PG) was the highest, and followed sorbitol, polyethylene glycol 200 (PEG 200) and glycerol. Elongation of the films prepared with glycerol was the highest, then sorbitol, PEG 200 and PG. WVP of films showed lower in order of PG, sorbitol, glycerol and PEG 200.75 decreased with the increment of plasticizer concentration, but elongation increased, The addition of both PG and PEG 200 effected weakly on elongation, so they were inadequate as plasticizer for the film. Mixtures of glycerol and sorbitol, which showed opposing both TS and elongation in the films, could control the physical properties of the films. With increasing relative humidity, TS decreased, while elongation and equilibrium moisture content increased. By adding the cross linkers such as ascorbic acid, citric acid and succinic acid, TS and m of films increased, while elongation decreased. Ascorbic acid, citric acid, succinic acid were most effective for TS at 0.2, 0.1 and $0.1\%, respectively. Laminated film with alaska pollack protein and corn zein improved TS above two times, reduced WVP about $20\~30\%$, as compared with the Elm from alaska pollack protein. Two films did not show the difference to oxygen permeability, but they showed about tenfold greater oxygen resistance than polyethylene film. Laminated film showed higher b and $\Delta$E value of color difference, lower a and L value than the film from alaska pollack protein.

High Density Tilapia Culture in a Recirculating Water System without Filter Bed (무여과순환수 탱크 이용 Tilapia의 고밀도 사육실험)

  • KIM In-Bae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.16 no.2
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    • pp.59-67
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    • 1983
  • An experiment on the rearing of tilapia stocked in closed recirculating tanks eliminating biological filter beds was carried out at the Fish Culture Experiment Station of the National Fisheries University of Pusan, from May 18 through October 21, 1982, and the growth rates, feed conversion, water quality, spawning prevention and space utilization efficiency were discussed. Finally discussed is the feasibility on the establishment of commercial production units. On the water quality, the water temperature ranged from $22.8^{\circ}C\;to\;29.1^{\circ}C$, and total ammonia arround 10 ppm or slightly up. Maintaining phytoplankton bloom was not successful probably because of the active consumption by the heavily stocked tilapia. Several attempts were made by changing the culture water with green water from a nearby earthen pond with results of fading-away in a couple of days. Feed conversions were relatively high ranging from 0.9 to 1.2 except for experiment 1 when the fish were not fully recovered from weakened wintering state. The feed used was partly laboratory prepared $25\%$ protein diet and mostly commercially available $39\%$ protein carp feed. Spawning was completely controlled during the experiment, resulting from density effect, which ranged from 10kg to 40.7kg per square meter with water depth of 0.5 to 0.6m. Space utilization efficiency was very high. Daily net production from the experiment division 3, which showed the highest result, was 6.206 kg per tank, which is calculated 3,235 metric tons per hectare per year, This time, water temperature ranged from 27.8 to $29.1^{circ}C$, average being $28.4^{circ}C$, and total ammonia arround 10 ppm. An estimation for the commercial set-up of the production system based on the results of experiment divisions which had initial stocking rate $15\;kg/m^2$ or up, is made. If the total facility, 8 tanks comprising $56\;m^2$ in surface area, is used for the present study, the yield would become 5,639 kg from 200 day rearing, which would be possible under double sheets vinyl house without additional heating, and it is thought feasible in the economic view point, when 10 or more units are operated.

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EVALUATION OF PERIODONTAL LIGAMENT CELL VIABILITY IN RAT TEETH ACCORDING TO VARIOUS EXTRA-ORAL DRY STORAGE TIMES USING MTT ASSAY (구강 외 노출시간에 따른 흰쥐 치아 치주인대세포 활성도의 MTT 검색법을 이용한 평가)

  • Jeon, In-Soo;Kim, Eui-Seong;Kim, Jin;Lee, Seung-Jong
    • Restorative Dentistry and Endodontics
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    • v.31 no.5
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    • pp.398-408
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    • 2006
  • The purpose of this study was to verify the usefulness of MTT analysis as a tool of measurement of the periodontal ligament cell viability from the extracted rat molar. A total of 80 Sprague-Dawley white female rat of 4 week-old with a body weight of 100 grams were used. The maxillary left and right, first and second molars were extracted under Ketamine anesthesia. Twenty-four teeth of each group (divided as five groups depending upon the time-lapse after extraction such as Immediate, 10, 20, 40 and 60 minutes) were immersed in $200{\mu}l$ of MTT solution (0.5 mg/ml) and processed for optical density measurements. Another 10 teeth of each group were treated as same as above and sectioned at $10{\mu}m$ for microscopic examination. All measurements values were divided by the value of hematoxylin-eosin staining which represented the volume of each corresponding samples. Immediate and 10 minute groups showed highest MTT values followed by 20, 40, and 60 minutes consecutively. Statistical significance (p<0.05) existed between all groups except in immediate versus 10 minute groups and 40 versus 60 minutes. Histological findings also showed similar findings with MTT results in crystal shape and crystal numbers between the experimental groups. These data indicate that in vivo MTT analysis nay be of value for evaluation of the periodontal ligament cell viability without time- consuming cell culturing processes.

A Study on the Origin and Transformation of Jeonju-Palkyung (전주팔경의 시원(始原)과 변용(變容)에 관한 연구)

  • Rho, Jae-Hyun;Son, Hee-Kyung;Shin, Sang-Sup;Choi, Jong-Hee
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.33 no.3
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    • pp.1-15
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    • 2015
  • Based on the analysis and interpretation of the headwords and poetic words of a group of eleven collecting sceneries of Jeonju, the origin and transformations of the Jeonju-Palkyung(Eight sceneries of Jeonju) investigated by a time-series analysis are as follows. As there is no collection of landscape with a formal structure similar to that of the current Jeonju-Palkyung, prior to the Palkyung by Chujae(秋齋) Cho Soo-Sam(趙秀三, 1762~1849), there is no significant problem in assuming the eight poems in Chujaejib(秋齋集) are the origins of the Jeonju-Palkyung, and it is estimated to have been produced in 1829. In the late-19th century poem 'Wansanseunggyeong(完山勝景)', 'the Palkyung in Yeollyeo Chunhyang Sujeolga', and 'the Palkyung delivered by poet Shin Seokjeong in the Japanese colonial era', only the 'Dongpogwibeom(東浦歸帆)' changed from Dongjipo to Dongchon of Bongdong as for 'Landscape Setting There($L_{ST}$)' according to changes in district administration; despite this change, the fact that they are not too different from the Palkyung of Cho Soo-Sam, also supports this. Moreover, according to the headword concordance analysis, it is proven that the Jeonju-Palkyung was established in the late-19th century and continued to be the region's representative sceneries even during the Japanese colonial era, and later 'Namcheonpyomo(南川漂母)' and 'Gonjimangwol(坤止望月)' were added to expand to the Jeonju-Sipkyung(ten sceneries of Jeonju). But when we see there are famous spots that are the origins of the Jeonju-Sipkyung, including Gyeonggijeon, Geonjisan, Jogyeongdan, Omokdae, and Girinbong, Deokjinyeon, and Mangyeongdae, all of which have great representational significance as the capital of Jeolla Provincial Office as well as of the place of origin for Joseon Dynasty in the grouping of sceneries during the early Joseon Dynasty, including "Paehyangsipyeong (沛鄕十詠)", "Gyeondosipyeong (甄都十詠)", and "Binilheonsipyeong(賓日軒十詠)", the beginnings of the semantic Jeonju-Palkyung should be considered up to the first half of Joseon Dynasty. During this period, not only the fine sceneries with high retrospective merit as the capital of Hubaekje, like Gyeonhwondo(甄萱都), but also the sceneries like Mangyeongdae that reminds people of Jeong Mongju(鄭夢周) and Yi Seonggye(李成桂) in the late period of Goryeo appeared, elevating the status of Jeonju as the capital of Hubaekje and shortening the historical gaps as the place of origin of the Joseon Dynasty. The Jeonju-Palkyung is an organic item that carries the history of the Joseon Dynasty after Hubaekje and has gone through many cycles of disappearing and reappearing, but it has continued to change and transform as the region's representative sceneries. The Jeonju-Palkyung is a cultural genealogy that helps one understand the 'Jeonju Hanpunggyeong(韓風景: the sceneries of Korea in Jeonju)', and the efforts to preserve and pass it down to the next generation would be the responsibility of the people of Jeonju.

Changes in Quality of Lettuce During Storage by Immersion-Type Hydrocooling (침지식 냉수냉각에 의한 상치의 저장중 품질변화)

  • Jeong, Jin-Woong;Kim, Byeong-Sam;Kim, Oni-Woung;Nahmgung, Bae;Park, Kee-Jai
    • Korean Journal of Food Science and Technology
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    • v.27 no.4
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    • pp.537-545
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    • 1995
  • Quality changes of lettuce were studied during storage to investigate the efficiency, cooling properties and the washing and storage effects of immersion-type hydrocooling. As a result of plotting the nondimensionalized lettuce temperature versus cooling time, its cooling rate coefficient was shown to be $-0.365\;min^{-1}{\sim}-0.255\;min^{-1}\;(R^2=0.99{\sim}0.88)$. Rate of weight loss was not significantly (p>0.05) different between lettuces with various treatment conditions during storage at $5^{\circ}C$. However, during storage at $15^{\circ}C$, weight loss of hydrocooled lettuce was lower than that of non-treated lettuce after from 10 to 15 days. Especially, The lettuce packed with PE was more effective than that packed with try in terms of packing condition after hydrocooling. Lettuce pretreated with sterilizing agent, packed with PE vinyl film, removed residual water after hydrocooling had lower decaying rate than any other lettuces. Changes of L and b values in hydrocooled lettuce were slower than those of non-treated one. During changes of chlorophyll content, the initial value, $115.7{\sim}147.3\;mg%$ was decreased to $50{\sim}60%$ after 25 days of storage at $5^{\circ}C$ and within 15 days of storage at $15^{\circ}C$. It could be presumed that the addition of sterilizing agent reduced the initial level of overall total and coliform count and its growth rate during storage. The respiration rate of hydrocooled lettuce at $5^{\circ}C$ was $23.95\;mg{\cdot}CO_2/kg\;hr$, which is 10% of those of non-treated lettuce.

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The Comparison and Index Components in Quality of Salt-Fermented Anchovy Sauces (멸치 액젓의 품질 비교 및 품질 지표성분에 관한 연구)

  • Oh, Kwang-Soo
    • Korean Journal of Food Science and Technology
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    • v.27 no.4
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    • pp.487-494
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    • 1995
  • To assay the quality of anchovy sauce, 10 kinds of commercial anchovy sauce(CAS) were purchased from markets and traditional anchovy sauce(TAS) were prepared. And their physicochemical-microbial characteristics were compared. The compositions of CAS were as followed; pH $5.5{\sim}5.7$, salinity $21.0{\sim}23.2%$, VBN $92.8{\sim}305.4\;mg/100g$, total nitrogen $928.0{\sim}1870.9\;mg%$, amino-nitrogen $338.6{\sim}680.3\;mg%$, and acidity $11.58{\sim}24.58\;ml$. The CAS was lower in pH, smaller in contents of VBN, total-N, amino-N and larger in contents of moisture, salinity than TAS. In Hunter values, CAS was generally lower in L, b values whereas higher in a and ${\Delta}E$ values than TAS. Viable cell counts on 0% NaCl-medium of CAS and TAS were $6.4{\times}10^1{\sim}3.0{\times}10^5\;and\;8.7{\times}10^4$, and those on 2.5% NaCl-medium were $0.8{\times}10^2{\sim}2.2{\times}10^5\;and\;1.6{\times}10^4{\sim}4.5{\times}10^5$, respectively. These viable cell counts in CAS and TAS were gradually decreased according to storage time. In composition of extractives, total free amino acid contents of CAS and TAS were $5498.5{\sim}12123.8\;mg%$, 12797.9 mg%, and these contents were gradually decreased during storage. The major amino acids were found glutamic acid, alanine and leucine in CAS, and alanine, glutamic acid, leucine and valine in TAS. Also contents of hypoxanthine, TMAO, TMA in CAS and TAS were shown $86.4{\sim}161.2\;mg%,\;51.6{\sim}99.2\;mg%,\;23.2{\sim}42.9\;mg%$ and 103.7 mg%, 128.8 mg%, 55.8 mg%, respectively. We may conclude from the results of present experiments that parts of tested CAS were somewhat putrefied and there was a great difference in the quality compared with TAS, whereas TAS maintained good conditions for preserving the quality until storage 2 years.

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