• Title/Summary/Keyword: $R_max$

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Identifications of a Sprout-Rot Pathogen Pseudomonas Species SN239 and Selection Resistant Soybean Line (콩나물 부패균 Pseudomonas sp. SN239 동정과 콩나물 부패병 내병성 계통 선발)

  • Lim, Jong-Soo;Do, Kum-Sook;Lee, Dong-Sun;Kang, Sang-Gu;Suh, Sang-Gon;Park, Eui-Ho
    • Journal of Life Science
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    • v.18 no.12
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    • pp.1771-1774
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    • 2008
  • Control microbial contamination in pathogens to soy sprouts has always been highly concerned in soybean sprout industries because the soybean sprouts are consumed largely as a nutritious fresh vegetable around the world. However, pathogens in soy sprouts are little known. Here, we isolated a strain of Pseudomonas sp. SN239 that caused severer symptoms in sprouts of many soybean cultivars. In phylogenetic relationships using 16S ribosomal RNA sequences of the Pseudomonas species, the identified Pseudomonas sp. SN239 was grouped with P. putita, P. plecoglossicida, P. monteilii and P. mevalonii. Thus, the bacterial strain SN239 might be a newly identified Pseudomonas species which closely related to P. putida. Furthermore, we found that a Korean indigenous soybean (Glycine max) cultivar YNPCSS3-19 has strong resistance against the Pseudomonas sp. SN239.

Purification and Characterization of Lipase from Acinetobacter sp. B2 Isolated from Oil­contaminated Soil (유류오염지역에서 분리한 Acinetobacter sp. B2로부터의 Lipase 정제 및 특성)

  • Son Seung Hwa;Park Kyeong Ryang
    • Korean Journal of Microbiology
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    • v.40 no.4
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    • pp.320-327
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    • 2004
  • Three hundreds thirty two bacterial colonies which were able to degrade crude oil were isolated from soil sam­ples that were contaminated with oil in Daejeon area. Among them, one bacterial strain was selected for this study based on its higher oil degrading ability, and this selected bacterial strain was identified as Acinetobactor sp. B2 through physiological-biochemical tests and analysis of its 16S rRNA sequence. Acinetobactor sp. B2 was able to utilize various carbohydrates but did not utilize trehalose and mannitol as a sole carbon source. Acinetobactor sp. B2 showed a weak resistance to antibiotics such as kanamycin, streptomycin, tetracycline and spectinomycin, but showed a high resistance up to mg/ml unit to heavy metals such as Ba, Li, Mn, AI, Cr and Pb. The optimal growth temperature of Acinetobactor sp. B2 was $30^{\circ}C.$ The lipase produced by Acinetobactor sp. B2 was purified by ammonium sulfate precipitation, DEAE-Toyopearl 650M ion exchange chromatography and Sephadex gel filtration chromatography. Its molecular mass was about 60 kDa and condition for the optimal activity was observed at $40^{\circ}C$ and pH 10, respectively. The activation energy of lipase for the hydrolysis of p­nitrophenyl palmitate was 2.7 kcal/mol in the temperature range of 4 to $37^{\circ}C,$ and the enzyme was unstable at the temperature higher than $60^{\circ}C.$ The Michaelis constant $(K_m)\;and\;V_{max}$ for p-nitrophenyl palmitate were 21.8 uM and $270.3\;{\mu}M\;min^{-1}mg^{-1},$ respectively. This enzyme was strongly inhibited by 10 mM $Cd^{2+},\;Co^{2+},\;Fe^{2+},\;Hg^{2+},$ EDTA and 2-Mercaptoethalol.

Extraction Method of Anthocyanin and Tannin Pigments in Colored Rice (유색미 안토시아닌계 및 탄닌계색소의 추출법)

  • Choi, Hae-Chune;Cho, Mi-Yeong;Kim, Soo-Un;Oh, Sea-Kwan
    • Applied Biological Chemistry
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    • v.39 no.4
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    • pp.327-331
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    • 1996
  • This experiment was conducted to establish the efficient extraction condition for anthocyanin and tannin pigments contained in rice bran of colored rices. Efficiency of the pigment extraction was maximum when the concentration of mired solvent of methanol(3) : ethanol(7) was 70%. In purple rite(anthocyanin pigment), ‘Kilimheugmi’, 80% ethanol containing 0.5% malic acid showed the highest extraction efficiency and stability with a maximum absorbance wavelength$(\lambda_{max})$ at 538 nm. In red rice(tannin pigment), ‘Jagwangdo’, 80% ethanol containing 0.01% citric acid showed the highest extraction efficiency and stability with a maximum absorbance wavelength$(\lambda_{max})$ at 456 nm. The relative optical density of the pigments increased until the solvent temperature was reached at $70^{\circ}C$, but drastically decreased over at $90^{\circ}C$ due to color change. The higher amount of the pigment was ertracted from the longer shaking time of the solvent. Ten minutes was enough for the grinding time of rite bran in solvent. Supernatant of the pigment extractives after one day storage at $4^{\circ}C$ in dark chamber revealed higher optical density than the filtration of the pigment extractives.

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Effect of Presowing Treatment with Growth Regulators on Different Growth and Yield Contributing Parameters in Soybean [Glycine max (L.) Merril] (식물생장과 조절제의 종자처리가 콩의 생장과 수량구성요소에 미치는 영향)

  • Eun Oh, Kwon;Ja Ock, Guh
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.32 no.4
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    • pp.392-402
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    • 1987
  • To know the effect of presowing seed soaking with some growth substances (kinetin, IAA, ethrel and salicylic acid) on vegetative growth and yield contributing parameters in soybean [Glycine max (L.) Merrill] the investigation was undertaken. The salient features from the study are;-All the treatments showed the enhancement effect on vegetative growth, viz. seediling emergence, germination percentage, plant height, number of leaves and branches per plant as compared with control, whereas salicylic acid delayed the seedling emergence process and lowered the germination percentage.-Nodule initiation, number of nodules and nodule weight were hastened and increased respectively under all the treatments whereas IAA showed an opposite effect on all the parameters at the early stages of nodule development.-Kinetin, IAA and ethrel showed the significant enhancement effect on the levels of biochemical parameters throughout the time of seed development whereas salicylic acid and water showed the tendency similar to that of control.-Yield and its components, viz. number of flowers, pods and seeds per plant were significant increased under all the treatments but they didn't show any significant enhancement effect on number of seeds per pod and pod setting rate. One hundred seed weight was lower under all the treatments, indicating the dilution effect resulting from incapability of increased number and size of source to provide the increased size of sink with assimilates.

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Supercritical Fluid Extraction of Sesame Oil with High Content of Sesamol (초임계 유체를 이용한 세사몰 고함유 참기름 추출 연구)

  • Ju Young-Woon;Son Min-Ho;Lee Ju-Suk;Lee Moon-Young;Byun Sang Yo
    • KSBB Journal
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    • v.20 no.3
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    • pp.205-209
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    • 2005
  • Studies for the commercial production of sesame oil using th supercriticl carbon dioxide were made. Characteristics of sesame oil containing one of natural antioxidant 'sesamol', which only exist at sesame seed were also studied during the supercritical fluid extraction. Among the various factors influencing the sesamol contents in the sesame oil, the roasting time and temperature were checked, because sesamol can be converted from sesamol in through pyrolysis. We found that the sesamol content was increased rapidly under the condition of roasting temperature over $200^{\circ}C$ with longer roasting time. The sesamol content was increased as the temperature and pressure increased, which was caused by increase of solubility of sesamol against sesamol oil. And the sesamol content was increased also with lower speed of supercritical fluid, which increased the contact time with the raw material. The sesamol content was also increased using water increase up to $1\%$ as the entrainer. When the extraction performance with the supercritical fluid was compared to the conventional compressed extraction, the sesamol content was increased up to 11.5 times with the entrainer.

Supercritical $CO_2$ Extraction of Sesame Oil with High Content of Tocopherol (초임계 이산화탄소를 이용한 토코페롤 고함유 참기름 추출)

  • Ju Young-Woon;Son Min-Ho;Lee Ju-Suk;Byun Sang Yo
    • KSBB Journal
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    • v.20 no.3
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    • pp.210-214
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    • 2005
  • The characteristics of sesame oil containing one of natural antioxidant, ' $\gamma$-tocopherol', were studied with the supercritical $CO_2$ extraction. Although $\gamma$-tocopherol has a lower vitamin E value in biological systems than $\alpha$-tocopherol, it is a more potent antioxidant with in oils. For the research of various factors influence to the $\gamma$-tocopherol contents increment, we have checked roasting time and temperature, as well as pressure, temperature and flow rate of supercritical fluid. As a result, we found that the $\gamma$-tocopherol content was maintained constant under the condition of roasting temperature over $200^{\circ}C$. With the longer roasting time, $\gamma$-tocopherol content was increased. Except 250 bar, the $\gamma$-tocopherol content was maintained constant under the condition of the various pressure of supercritical fluid. But $\gamma$-tocopherol content was increased with lower flow rate of supercritical fluid from 1 $m{\ell}$/L to 3 $m{\ell}$/L. When the extraction performance with the supercritical fluid was compared to the conventional compressed extraction, $\gamma$-tocopherol content was increased up to 1.6 times.

Development of an Actuated Traffic Signal Control Strategy to Minimize Dilemma Zone (딜레마 구간 최소화를 위한 감응식 신호제어전략의 개발)

  • Kim Youngchan;Huh Jung Ah
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.1 no.1
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    • pp.58-69
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    • 2002
  • Most of the traffic accidents are a rear-end collision and a clash generated in the signalized intersection on the local roads. So, it is demanded that the high-quality of signal control and dilemma zone control. According to the cases generated by foreign countries, we established the strategies which are composed of Volume-Density Control, strategy of the dilemma zone control using R-detector (microwave detector) In Japan and EC-DC Control. MOEs(Measure of effectiveness) are car numbers in the dilemma zone , max-out probability in the safe side and the average stopping delay in the progress side. We choose a signalized intersection in rural highway to analyze the effect of the strategies and practiced an on-the-spot survey. The result of the survey is applied to the basic data in the simulator. Consequently, strategy of the dilemma zone control using R-detector(microwave detector) in Japan is the best effective in the safe side and EC-DC control is the best in the progress side. Based on the result, we developed the effective strategy of the signal control . This strategy is composed of the strategy of Japan and the detector on the stopping line used in the EC-DC control. On the result of the analysis, new strategy is the best effective in two sides.

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Effect of Hot Water Extract Powder from Safflower (Carthamus tinctorius L.) Seed on Quality of Noodle (홍화씨 열수추출 분말 첨가가 국수의 품질에 미치는 영향)

  • Kwak, Dong-Yun;Kim, Jun-Han;Choi, Myung-Sook;Shin, Seung-Ryeul;Moon, Kwang-Deog
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.31 no.3
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    • pp.460-464
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    • 2002
  • Quality of noodle processed by addition of hot water extract powder from roasted safflower seed (RSHE) was investigated. Proximate compositions of RSHE was 4.70% of moisture, 32.63% of crude Protein, 6.52% of crude fat, 15.62% of crude ash and 40.53% of carbohydrate. There was no significant difference (p<0.05) in hunter's color value between noodles with and without RSHE. The ‘L’vague of noodle processed by addition of powder from roasted safflower seed (RSP) was very low and significantly different (p<0.05) from other products. With the increase of RSHE addition, the volume and weight of cooked noodles increased (R$^2$=0.9688). The breaking force of dry noodle decreased with the increase of RSHE addition. In the mastication test of cooked noodles, max. weight, strength and hardness increased with the increase of RSHE addition. Dry noodle with 0.3% and 0.5% RSHE recorded high rank, but that with RSP recorded the lowest rank in score of appearance and color by sensory evaluation. The noodle processed with 0.3∼0.5% RSHE showed high sensory quality.

Biochemical Characterization of an Extracellular Xylanase from Aestuariibacter sp. PX-1 Newly Isolated from the Coastal Seawater of Jeju Island in Korea (대한민국 제주도 연안 해수에서 새롭게 분리한 Aestuariibacter sp. PX-1이 생산하는 자일라네이즈의 생화학적 특성)

  • Kim, Jong-Hee
    • Microbiology and Biotechnology Letters
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    • v.48 no.2
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    • pp.215-222
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    • 2020
  • The marine microorganism PX-1, which can hydrolyze xylan, was isolated from coastal sea water of Jeju Island, Korea. Based on the 16S rRNA gene sequence and chemotaxonomy analysis, PX-1 was identified as a species of the genus Aestuariibacter and named Aestuariibacter sp PX-1. From the culture broth of PX-1, an extracellular xylanase was purified to homogeneity through ammonium sulfate precipitation and subsequent adsorption chromatography using insoluble xylan. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration chromatography estimated the molecular weight of the purified putative xylanase (XylA) as approximately 64 kDa. XylA showed xylanase activity toward beechwood xylan, with a maximum enzymatic activity at pH 6.0 and 45℃. Through thin-layer chromatographic analysis of the xylan hydrolysate produced by XylA, it was confirmed that XylA is an endo-type xylanase that decomposes xylan into xylose and xyloligosaccharides of various lengths. The Km and Vmax values of XylA for beechwood xylan were 27.78 mM and 78.13 μM/min, respectively.

Yield and Quality of Black Soybean (Glycine max L.) in Paddy Field under Different Sowing Dates (검정콩 논재배에서 파종시기가 수량 및 종실 특성에 미치는 영향)

  • Jo, Yeong-Min;Heo, Byong Soo;Choi, Kyu-Hwan
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.67 no.1
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    • pp.53-60
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    • 2022
  • Recently, Black soybean (Glycine max L. Merr.) is being cultivated in paddy fields instead of rice. However, research related to the effective sowing date is insufficient in paddy fields. This study aimed to identify the sowing date for stable cultivation of black soybean by investigating its yield and seed characteristics in a paddy field. In the study, cultivation experiment with five different sowing dates (May 25, June 10, June 25, July 10, July 25) were conducted in 2019 and 2020. Days from sowing to flowering can be shortened by delaying the sowing date. In the present study, the yield of black soybean in paddy fields was the highest with June 10 as the sowing date and was calculated as 224 kg·10a-1 and 200 kg·10a-1 in 2019 and 2020, respectively. However, the highest values of seed coat cracking was 51.1±5.1% and that of total anthocyanin contents was the 3.99±0.72 mg/g, both of which were observed in 2020 for the experiment with May 25 as the sowing date. Regression analysis showed a positive correlation (R2=0.9312) between soil water contents and seed coat cracking rate during the flowering period. Hence, the soil water contents during the flowering period would have a negative effect on the seed coat development.