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Growth Inhibition against Contaminants in Aseptic Chocolate Milk Using Physicochemical Methods (물리.화학적 처리에 의한 멸균 초콜릿 우유 오염균의 생육억제 효과)

  • Choi, Moon-Kyoung;Yoon, So-Young;Lee, So-Young;Kim, Koth-Bong-Woo-Ri;Lee, Chung-Jo;Jung, Ji-Yeon;Kwak, Ji-Hee;Kim, Min-Ji;Kim, Dong-Hyun;SunWoo, Chan;Lee, Ju-Woon;Byun, Myung-Woo;Ahn, Dong-Hyun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.8
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    • pp.1157-1163
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    • 2011
  • This study was conducted to investigate the cause of microbiological contaminants in aseptic chocolate milk and evaluate the effect of a physicochemical treatment on the growth inhibition of isolated bacterial strains. The bacterium isolated from aseptic chocolate milk was identified as Bacillus lentus and was named B. lentus M1. In the heat and pH treatment, the growth of B. lentus was inhibited at 110$^{\circ}C$ for >15 min and at pH's <5 and >10. An electrolyzed water treatment against B. lentus M1, revealed 5 mm growth past the inhibition zone. The effect of ozone gas on B. lentus M1 growth was evaluated using viable cell counts. When the initial number of B. lentus M1 was $10^2$ and $10^3$ CFU, the bacteria were completely suppressed by ozone gas treatment for 10 and 30 min, respectively. In a microwave treatment, B. lentus M1 was sterilized following microwave treatment for 1 min. As the result of ${\gamma}$-irradiation against B. lentus M1, numbers decreased as the ${\gamma}$-irradiation dosage increased. These results show the growth inhibition effects against contaminants in aseptic chocolate milk using physicochemical treatments.

Callus Initiation and Organ Formation from in vitro Culture of Pelargonium spp. (In Vitro Culture에 의한 Pelargonium spp.의 Callus 유도 및 기관분화에 관하여)

  • Lee, Chun-Ha;Chung, Hae-Joon
    • The Journal of Natural Sciences
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    • v.4
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    • pp.143-159
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    • 1991
  • In order to investigate the micropropagation of Pelargonium, 2 cultivars of P. peltatum 'Pouletta' and P. zonale 'Pinto Red' were cultured in vitro on the MS basal medium supplemented with various concentrations of growth regulators. It attempted to study the induction of callus and the differentiation of organs from leaf disc, petiole segments, stem segments. hypocotyle segments and flower stalk segments. The results are summarized as follows; A. As for the initiation of callus, stem explant was proved to be the most suitable one among various explants of P. zonale 'Pinto Red'. The medium was supplemented with 1.0mg/1 BAP and 1.0mg/1 NAA. As NAA concentration increased, callus formation was enhanced, but higher concentration of NAA inhibited callus fromation. Leaf and hypocotyle explants showed less callus formation than stem and petiole explants. B. In P. zonale 'Pinto Red' petiole culture, the condition of cullus culture such as hormone concentration resulted in affecting shoots differentiation. The best result of shoots formation from the callus reculture were obtained from the combination of 0.5-1.0mg/1 BAP and 0.1-1.0mg/1 NAA when the callus was cultured in 1.0mg/1 BAP and 0.05mg/1 NAA. When the callus was cultured in medium without BAP, the shoot was not differentiated in subculture regardless to BAP and NAA concentration. and only callus was formed. C. Poly-phenol substance was observed in MS medium supplemented without PVP, in which callus was not formed from the leaf of P. peltatum 'Rouletta'. Polyphenol substance was not observed in MS medium supplemented with PVP, in which callus formation was increased. D. The callus formation of P. peltatum 'Rouletta' showed the stem explant being best result. The best result particularly in the stem explant among others. The optimal hormonal concentration was 0.1mg/1 NAA and 5.0mg/1 BAP. The shoot formation was observed at 0.05mg/1 NAA and 1.0mg/1 BAP, 0.1mg/1 NAA and 5.0mg/1 BAP. The shoot was malformed and the tissue recultured turned necrotic.

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Antimicrobial Activity of Medicinal Herbs against Staphylococcus aureus (Staphylococcus aureus에 대한 한약재의 항균활성)

  • Cho, Jae-Yong;Lim, Sang-Cheol;Choi, Il
    • Korean Journal of Plant Resources
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    • v.19 no.4
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    • pp.491-496
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    • 2006
  • Antimicrobial activity of 18 different traditional medicinal herbs extracts against Staphylococcus aureus was determined by a paper disc method. The Prunella vulgaris, Caesalpinia sappan and Rhus javanica extracts in 5 mg/ml, Poncirus trifoliata, Lonicera japonica and Seutellaria baicalensis extracts in 10 mg/ml and Schizandra chinensis, Alpinia katsumadai, Siegesbeckia orientalis extracts in 30 mg/ml showed a significant antimicrobial activity against Staphylococcus aureus. Minimum inhibitory concentrations of medicinal herbs extracts were in the range of $1{\sim}34\;mg/ml$ and $1{\sim}46\;mg/ml$, in the case of MeOH extracts and EtOH extracts, respectively. In addition, the antimicrobial activity of each solvent fraction was most significant with EtOAc layer. Optical density at 620nm after 24 hours incubation of Staphylococcus aureus in the presence of 100, 300 or 500 ppm of Caesalpinia sappan extract ranged from 0.02 to 0.03 compared to 0.4 in the absence of Caesalpinia sappan extract, indicating that growth of Staphylococcus aureus was significantly inhibited within 24 hours by the addition of at least 100 ppm of Caesalpinia sappan extract. Optical density at 620 nm after 24 hours incubation of Staphylococcus aureus in the presence of 300 ppm of Rhus javanica extract ranged from 0.02 to 0.03 compared to 0.4 in the absence of Rhus javanica extract, indicating that growth of Staphylococcus aureus was also significantly inhibited within 24 hours by the addition of at least 300 ppm of Rhus javanica extract. Optical density at 620 nm after 24 hours incubation of Staphylococcus aureus in the presence of 300 ppm of Seutellaria baicalensis extract ranged from 0.02 to 0.07 compared to 0.4 in the absence of Seutellaria baicalensis extract, indicating that growth of Staphylococcus aureus was also significantly inhibited within 24 hours by the addition of at least 300 ppm of Seutellaria baicalensis extract. In conclusion, these findings suggest that extracts from medicinal herbs may play important roles for antimicrobial activities against Staphylococcus aureus.

The fracture resistance of heat pressed ceramics with wire reinforcement (금속선 강화에 따른 열 가압 도재의 파절저항)

  • Jo, Deuk-Won;Dong, Jin-Keun;Oh, Sang-Chun;Kim, Yu-Lee
    • The Journal of Korean Academy of Prosthodontics
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    • v.47 no.2
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    • pp.191-198
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    • 2009
  • Statement of problem: Ceramics have been important materials for the restoration of teeth. The demands of patients for tooth-colored restorations and the availability of various dental ceramics has driven the increased use of new types of dental ceramic materials. Improved physical properties of theses materials have expanded its use even in posterior crowns and fixed partial dentures. However, ceramic still has limitation such as low loading capability. This is critical for long-span bridge, because bridge is more subject to tensile force. Purpose: The wire reinforced ceramic was designed to increase the fracture resistance of ceramic restoration. The purpose of this study was to evaluate the fracture resistance of wire reinforced ceramic. Material and methods: Heat pressed ceramic(ingot No.200 : IPS Empress 2, Ivoclar Vivadent, Liechtenstein) and Ni-Cr wire(Alfa Aesar, Johnson Matthey Company, USA) of 0.41 mm diameter were used in this study. Five groups of twelve uniform sized ceramic specimens(width 4 mm, thickness 2 mm, length 15 mm) were fabricated. Each group had different wire arrangement. Wireless ceramic was used as control group. The experimental groups were divided according to wire number and position. One, two and three strands of wires were positioned on the longitudinal axis of specimen. In another experimental group, three strands of wires positioned on the longitudinal axis and five strands of wires positioned on the transverse axis. Three-point bending test was done with universal testing machine(Z020, Zwick, Germany) to compare the flexural modulus, flexural strength, strain at fracture and fracture toughness of each group. Fractured ceramic specimens were cross-sectioned with caborundum disc and grinded with sandpaper to observe interface between ceramic and Ni-Cr wire. The interface between ceramic and Ni-Cr wire was analyzed with scanning electron microscope(JSM-6360, JEOL, Japan) under platinum coating. Results: The results obtained were as follows: 1. The average and standard deviation in flexural modulus, flexural strength and fracture toughness showed no statistical differences between control and experimental groups. However, strain was significantly increased in wire inserted ceramics(P<.001). 2. Control group showed wedge fracture aspects across specimen, while experimental groups showed cracks across specimen. 3. Scanning electron microscopic image of cross-sectioned and longitudinally-sectioned specimens showed no gap at the interface between ceramic and Ni-Cr wire. Conclusion: The results of this study showed that wire inserted ceramics have a high strain characteristic. However, wire inserted ceramics was not enough to use at posterior area of mouth in relation to flexural modulus and flexural strength. Therefore, we need further studies.

Evaluations on Deodorization Effect and Anti-oral Microbial Activity of Essential Oil from Pinus koraiensis (잣나무 정유의 소취효과 및 구강균에 대한 항균활성 평가)

  • Hwang, Hyun Jung;Yu, Jung-Sik;Lee, Ha Yeon;Kwon, Dong-Joo;Han, Woong;Heo, Seong-Il;Kim, Sun Young
    • Korean Journal of Plant Resources
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    • v.27 no.1
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    • pp.1-10
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    • 2014
  • Essential oils of various plants have been known for potential biological effects such as antibacterial, antifungal, spasmolytic, antiplasmodial activities and insect-repellent property. Recently, the essential oils have attracted considerable interest in oral disease therapy. This essential oil has been known as being effective on easing sick house syndrome, giving forest aroma therapy effect and acting as repellent against pest. The essential oil of Pinus koraiensi, a native plant from Hongcheon-gun, Gangwon-do, was obtained by hydrodistillation. In light of its medicinal importance, in this study its composition, antibacterial activity and the reducing effect of offensive odor have been analyzed. The composition of essential oil was determined by GC and GC-MS. We have identified 14 compounds, of which 1R-${\alpha}$-pinene (19.38 %), 3-carene (10.21 %), camphene (9.82 %), limonene (9.00 %), bicyclo[2,2,1] heptan-2-ol (8.76 %) and ${\beta}$-phellandrene (7.98 %) were the main components. Essential oils from P. koraiensis, Chamaecyparis obtusa, Abies holophylla and Pinus densiflora were compared in terms of alleviating effect of malodors caused from formaldehyde, ammonia, trimethylamine and methylmercaptan. P. koraiensis essential oil was found to decrease the amounts of ammonia and trimethylamine by 75.17 % and 77.36 %, respectively. Antibacterial activity against Streptococcus mutans and Streptococcus sobrinus, which were known as oral cavity inducer, was investigated using the paper disc agar diffusion method. The inhibition zone was observed against S. mutans (5.97 mm) and S. sobrinus (1.40 mm), respectively. P. koraiensis essential oil shown effective deodorization and inhibitory activity against oral cavity in this study might be potential material in oral sanitary industry.

Comparison of Disk Tension Infiltrometer and van Genuchten-Mualem Model on Estimation of Unsaturated Hydraulic Conductivity (장력 침투계(Disk Tension Infiltrometer)와 van Genuchten-Mualem 모형 적용에 따른 불포화수리 전도도의 비교 해석)

  • Hur, Seung-Oh;Jung, Kang-Ho;Park, Chan-Won;Ha, Sang-Keun;Kim, Geong-Gyu
    • Korean Journal of Soil Science and Fertilizer
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    • v.39 no.5
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    • pp.259-267
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    • 2006
  • Hydraulic conductivity is the rate of water flux on hydraulic gradient. The van Genuchten Mualem (VGM) model is frequently used for describing unsaturated state of soils, that is composed with the function of soil water potential and soil water content and requests various parameters. This study is to get the value of VGM parameters used Rosetta computer program based on neural network analysis method and to calculate VGM parameters. VGM parameters included Ko(effective saturated hydraulic conductivity), ${\theta}r$(residual soil water content), ${\theta}s$(saturated soil water content), L, n and m. The unsaturated hydraulic conductivity at 10 kPa was calculated by using Rosetta program. Unsaturated hydraulic conductivities of 17 soil series at 1, 3, 5, 7 kPa were also obtained by applying saturated hydraulic conductivity by disk tension infiltrometer based on Gardner and Wooding's equation. Water flow at the water potential of 3 kPa was very low except Namgye, Hagog, Baegsan, Sangju, Seogcheon, Yesan soil series. Unsaturated hydraulic conductivity at 1 kPa showed the highest value for Samgag soil series and was in order of Yesan, Hwabong, Hagog and Baegsan soil series. Those of Gacheon, Seocheon and Ugog soil series were very low. When the value by VGM was compared with the value by disc tension infiltrometer, there was a tendency with exponential function to soils without gravel but there was no tendency to soils including gravel. Conclusively, it would be limited that VGM model for unsaturated hydraulic conductivity analysis applies to Korean agricultural land including gravel and having steep slope, shallow soil depth.

Treatment by Injection-Acupuncture with Apitoxin and Apitoxin Combined by Chinese Herbal Medicine in Patients with Canine Bind Limb Paralysis : Case Report (후지마비견(後肢痲痺犬)에 대한 봉독(蜂毒) 약침(藥鍼) 및 봉독(蜂毒) 약침(藥鍼)과 한약제(漢藥劑)의 병용치료(倂用治療) : 증례보고(症例報告))

  • Jun, Hyung-Kyou;Park, Se-Kun;Kim, Duck-Hwan;Kim, Mun-Ho;Hsu, Chin-Yuan;Hsu, Chin-Ling;Liao, Jim-Cai;Chueh, Hao-Jen;Cheng, Han-Wen
    • Journal of Veterinary Clinics
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    • v.24 no.2
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    • pp.225-228
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    • 2007
  • The therapy by injection-acupuncture (AP) with bee-venom (apitoxin) and injection-AP with apitoxin combined by administration of Chinese herbal medicine was applied in 2 cases with canine intervertebral disc disease (IVDD). Case 1 was diagnosed as thoraco-lumbar IVDD (T11-T12, T12-T13, L3-L4 and L4-L5) and case 2 was diagnosed as IVDD at T10-T11 and T12-T13, respectively Injection-AP with apitoxin($Apitoxinc{(R)}$, total $200{\mu}g$ of apitoxin, 0.1 ml/acupoint) plus physical exercise (walking with gocart, TID/day) and aquatherapy (swimming treatment, BID/week) were given to each patient. The used acupoints were GV20 (Bai Hui), GB30 (Huan Tiao), ST36 (Zu San Li), GB34 (Yang Ling Quan), ST40 (Feng Long), ST41 (Jie Xi) and BL40 (Wei Zhong), the lesions, and trigger points. In addition, Chinese herbal medicine (Koda Pharmaceutical Co., Taiwan) including Zheng Gu Zi Jin Dan (正骨紫金丹 : 1 g), Shiuh Duann(續斷 : 0.2 g), Du Zhong(杜仲 : 0.2 g), Mo Yao(沒藥 : 0.2 g), Ru Xian(乳香 : 0.2 g) and Pyrite(自然銅 : 0.2 g) were orallly mdeicated BID for 0\9days in case 2. Walking was possible after session 11 for 4 weeks in case 1 and after session 6 for 2 weeks in case 2, respectively.

Antimicrobial Activity of the Sargassum fulvellum Ethanol Extract and the Effect of Temperature and pH on Their Activity (모자반 에탄올 추출물의 항균활성과 열 및 pH 안정성)

  • Yoon, So-Young;Lee, So-Young;Kim, Koth-Bong-Woo-Ri;Song, Eu-Jin;Lee, So-Jeong;Lee, Chung-Jo;Park, Na-Bi;Jung, Ji-Yeon;Kwak, Ji-Hee;Nam, Ki-Wan;Ahn, Dong-Hyun
    • Korean Journal of Food Science and Technology
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    • v.42 no.2
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    • pp.155-159
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    • 2010
  • The antimicrobial activity of Sargassum fulvellum (SF) was investigated using the agar diffusion assay and MIC test. In addition, the stability of this activity under extreme heat and pH conditions was examined. The SF ethanol extract was shown to display strong antimicrobial activities against B. subtilis, C. perfringens, L. plantarum, S. aureus, L. monocytogenes, S. cerevisae and C. tropicalis in the agar diffusion assay at the concentration of 4 mg/mL. The MIC value of the SF ethanol extract against the tested microbes ranged from 0.05 to 0.0063%. In the heat and pH stability test, the antimicrobial activity of the SF ethanol extract was not altered when the temperature was maintained at $121^{\circ}C$ for 15 min, and it was also not affected in the pH range of 2-10. These results suggest that the SF ethanol extract is highly stable against drastic changes in temperature and pH.

Isolation, Purification and Some Properties of Polyphenol Oxidase from Pear (배과실(果實)의 Polyphenol Oxidase의 분리(分離) 정제(精製) 및 그 특성(特性))

  • Kang, Yoon Han;Sohn, Tae Hwa;Choi, Jong Uck
    • Current Research on Agriculture and Life Sciences
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    • v.4
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    • pp.55-64
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    • 1986
  • Polyphenol oxidase in japanese pear (Pyrus communis var. mansamkil) was isolated, partially purified and its some properties were investigated. Polyacrylamide disc gel electrophoresis indicated two bands with polyphenol oxidase activity in the extract from acetone dry powder of par flesh. These two polyphenol oxidases (PPO A and PPO B) were purified through acetone precipitation and diethylaminoethyl cellulose column chromatography. PPO A and B were purified 7.8 fold and 8.7 fold by the present procedure, respectively. The Rm values of partially purified PPO A and B were estimated to be 0.58 and 0.68, respectively. The optimum temp, and pH of PPO A activity were $33^{\circ}C$ and pH 7.0, while those of PPO B were $30^{\circ}C$ and pH 4.2, respectively. Two PPO were unstable over the temperature of $60^{\circ}C$. The substrate specificity of pear PPO showed high affinity toward o-diphenolic compounds, especially catechol in PPO A and chlorogenic acid in PPO B, but inactive toward m-diphenol, p-diphenol and monophenols. PPO A showed affinity toward the trihydroxyphenolic compound. $Zn^{{+}{+}}$ activated the PPO A activity but $Fe^{{+}{+}}$ inhibited PPO B activity, while $Fe^{{+}{+}}$ and $Zn^{{+}{+}}$ activated the PPO B activity, while $Fe^{{+}{+}}$ and $Zn^{{+}{+}}$ activated the PPO B activity but $K^+$, $Mg^{{+}{+}}$, $Ca^{{+}{+}}$ and $Hg^{{+}{+}}$ inhibited at 10mM concentration. $Cu^{{+}{+}}$ activated the enzyme action at low concentrations but inhibited at high concentration. Inhibition studies indicated that L-ascorbic acid, L-cysteine and thiourea were most potent. The Km values of PPO A and PPO B for catechol were 20mM and 14.3mM, respectively.

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Anatomical Studies on the Features of Rays in Compression Wood of Korean Red Pine(Pinus densiflora S. et Z.) (소나무(Pinus densiflora S. et Z.) 압축이상재(壓縮異常材)의 방사조직(放射組織) 특성(特性)에 관한 해부학적(解剖學的) 연구(硏究))

  • Chung, Youn Jib;Lee, Phil Woo
    • Journal of Korean Society of Forest Science
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    • v.78 no.2
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    • pp.119-131
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    • 1989
  • This experiment was executed to investigate and compare qualitative and quantitative anatomical features in compression wood, opposite wood, and side wood formed in a bent stem, a straight branch, and an exposed horizontal root of Korean red pine(Pinus densiflora S. et Z.). The respective four discs containing compression wood taken at 20cm interval both in stem and branch as well as a disc containing well developed compression wood from horizontal root were analyzed. Percentage of compression wood and eccentricity showed decreasing tendency with the increasing distance in height direction of stem and length direction of branch. The qualitative anatomical features of compression wood appeared to differ from those of side and opposite wood in very gradual tracheid transition from earlywood to latewood, roundish tracheid shape on cross surface, tracheid distortion at tip on radial surface, existence of intercellular space, and helical cavity in tracheid wall. And the differences in these qualitative features among the compression wood, opposite wood, and side wood became less intensive with the decreasing trends in percentage of compression wood and eccentricity. The quantitative anatomical features in compression wood also appeared to be wider in that respective widths of fusiform and uniseriate ray than those of opposite and side wood, but the heights of fusiform and uniseriate ray in compression wood were smaller than in opposite and side wood. The number of horizontal resin canal(fusiform ray) and uniseriate ray, however, showed no differences among the compression wood, opposite wood, and side wood. And the number of vertical resin canal in unit area, $4{\pi}mm^2$ of compression wood was fewer than that in opposite wood, whereas numerous vertical resin canals contained in a growth ring. These rays of compression wood seemed to be characterized by smaller height and wider width than those of opposite and side wood.

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