• 미생물학회지
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• 제27권3호
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• pp.310-315
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• 1989

식물의 잎에 세균성 정무늬병을 야기시키는 식울 병원성균인 Pseudomonas syringae pv. tuhaci는 tabtoxin 이라는 phytotoxin 을 생성하는데 이 toxin을 미생물학적으로 간편하게 검색하는 방법플 여러가지 지시균주를 사용하여 각족 배지에서 검토하였다. Minimal A agar medium에서는 tabtoxin 검색에 Agrobactcrium tumefaces가 가장 유용한 균주였으며 minimal glucose agar m$\varepsilon$dium 에서도 역시 마찬가시의 견과를 얻였다 Complex agar medium 에서는 사용된 모든 지시균주에 대해 증식저지환이 형성되지 않아, tabtoxin이 생성되지 않음알수 있었다. 배양온도에 따른 tabtox의 생성능은 $20^{\circ}C$ 빛 $30^{\circ}C$ 에서 최적이였으며 배양시간이 경과함에 따라 tabtoxin 생성량이 증가 하였다. Glutamine을 minimal glucose agar medium에 첨가하여 tabtoxin 에 대한 지시 균주의 반응은 첨 가한 glutamine 의 양이 증가할수록 tabtoxin에 의한 생육억제가 감소함을 알 수 있었다.

• 한국동물위생학회지
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• 제44권3호
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• pp.149-155
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• 2021

In virucidal efficacy testing, the chemical inactivation cannot be determined for all viruses due to the difficulties or the inability to culture sufficiently or the risk of exposure to the viruses. Therefore, disinfectants against these viruses could be evaluated by different methods and surrogate viruses are used as alternative. In this study we developed a method for efficacy testing of veterinary disinfectants using one of the candidate surrogate viruses, bacteriophage MS2, as part of the research on the selection of surrogate viruses for efficiency of efficacy testing of veterinary disinfectants. This method is based on the Animal and Plant Quarantine Agency (APQA) guidelines for efficacy testing of veterinary disinfectants. Bacteriophage and disinfectant are reacted in suspension in accordance with the APQA guidelines and then a newly established double agar layer method is applied for the efficacy test. The double agar layer method is summarized as follows: 1) The bottom agar with 1.5% agar is boiled and cooled before poured into petri dishes at volume of 20 mL, and dried under biological safety cabinet. 2) The top agar with 0.7% agar is boiled and kept at 50℃ before E. coli culture was seeded. 3) The serially diluted bacteriophage MS2-disinfectant mixtures 0.05 mL and E. coli host 0.01 mL (OD₆₀₀ 0.2~0.3) are mixed with 5 mL of top agar and incubate them at 50℃ for 5 min for reaction. 4) The resulting mixture is poured over top of a bottom agar plate and rocked sufficiently to ensure that the top agar covers the entire surface of the bottom agar. 5) The double agar layer is then placed under biological safety cabinet to allow the agar layer to solidify and subsequently incubated at 37℃ for 24 hr. 6) Following incubation, the plates may be inspected for plaques and record results.

• 한국미생물·생명공학회지
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• 제22권5호
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• pp.561-563
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• 1994

For the more effective isolation of soil actinomycetes, we have developed HHV (Hair hydrolysate-vitamin) agar medium, containing hair as the sole source of carbon and nitrogen. The HHV agar medium was superior to other media such as colloidal chintin agar, glycerol-arginine agar and starch-casein-nitrate agar, and HV (humic acid-vitamin) agar. The maximum effect of this medium has been shown in hair dry weight 0.4 g/l medium. Of each soil sample, the greatestest number of actinomycetes was isolated from the potato annual planted soil among the tested samp- les. The genus of actinomycetes isolated from the potato annual planted soil sample was identified such 5 group as Stretomyces, Micromonospora, Microbispora, Nocardia and Saccharopolyspora.

• Journal of Plant Biology
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• 제6권1호
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• pp.8-10
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• 1963

1. 한천배양기상에서의 토마토즙함량과 사탕무 갈반병균 Cercospora beticola 의 포자형성도와의 관계를 조사하였다. 2. 감자즙한천배양기상에서 포자를 형성하지 않는 배양균 C. beticola는 토마도즙을 10% 이상 함유하고 있는 한천배양기상에서 이식후 48시간만에 포자를 형성하였다. 3. 토마도즙을 10% 함유하고 있는, 한천배양기상에서는 극히 소수의 포자가 형성되었으나, 토마도즙 함량이 20% 이상인 한천배양기상에서는 다수의 포자가 형성되었고, 한천배양기상의 토마도즙함량이 높을수록 더 많은 포자가 형성되었다.

• 한국식품영양과학회지
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• 제39권5호
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• pp.764-768
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• 2010

식품공전에 Cronobacter sakazakii 분리배지로 등재되어 있는 3종의 분리배지에 대한 평가실험을 실시하였다. Chromogenic Enterobacter sakazakii agar, Enterobacter sakazakii agar가 VRBG agar에 비하여 뚜렷한 색택과 모양의 집락을 생성하였다. 3종의 분리배지 모두 30종의 Cronobacter sakazakii에 대한 sensitivity가 100%로 측정되었지만 Cronobacter sakazakii 이외의 Enterobacteriaceae 균주를 이용한 specificity 실험에서는 Chromogenic Enterobacter sakazakii agar, Enterobacter sakazakii agar가 100%로 측정되었지만 VRBG agar는 0%로 측정되었다. 인위적으로 접종한 식품에서의 회수율은 실험에 공시된 3종 배지에서 커다란 차이가 없었다.

• 한국식품조리과학회지
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• 제4권1호
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• pp.17-26
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• 1988

The polysaccharide produced by pseudomonas elodea, Gellan gum, was rheologically characterized, compared with agar. Rheological properties were determined from the change in the value of intrinsic viscosity with the pH and salt concentration. At the range of pH 2∼ll and salt 0∼0.16M KC1, the intrinsic viscosity of Gellan gum ranged from 8.8 to 21.2dl/g and agar ranged from 1.97 to 11.46d1/g. In the absence of salt, the intrinsic viscosity of Gellan gum increased as the pH of solution increased up to neutral pH then decreased slightly at alkaline pH, whearas the intrinsic viscosity of agar increased as the pH of solution increased up to pH 9 then decreased slightly. Intrinsic viscosity of Gellan gum and agar decreased with an increase in salt concentration. The chain stiffness parameter for the Gellan gum was 0.033. The overlap parameter of Gellan gum and agar were 0.047g/dl and 0.087g/dl, respectively. Gellan gum and agar were shear rate dependent or pseudoplastic. The yield stress and proportionality constant of Gellan gum increased slightly as the concentration increase, on the other hand, the shear index of Gellan gum showed a maximum at 0.75g/dl and gradually decreased as the concentration increase. The apparent viscosity of Gellan gum and agar decreased as the temperature increase. A lower concentration of the divalent cations calcium and magnesium is required to obtain maximum gel strength than for the monovalent cations sodium and potassium.

• 한국식품조리과학회지
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• 제7권2호
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• pp.19-23
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• 1991

본 연구에서는 gel화를 유도할 수 있는 첨가제를 첨가하여 만든 5가지 옥수수 전분 gels와 아무것도 첨가하지 않은 control옥수수 전분 gel의 관능적 물성적 특성을 조사 비교하였다. 1. 관능검사를 실시한 결과 \circled1 Agar의 hardness는 control보다 유의하게 높았고, pectin은 control 보다 유리하게 낮았다. \circled2 CMC와 pectin의 adhesiveness는 control 보다 유의하게 높았고 agar는 control보다 유의하게 낮았다. \circled3 전체적인 acceptability는 CMC와 Pectin은 control보다 유의하게 선호도가 낮았고 나머지 시료들은 control과 유의차가 없었다. 2. Instron을 이용한 물성검사 결과 \circled1 Agar의 hardness는 control보다 유의하게 높았고, 나머지 시료들의 hardness는 control보다 유의적으로 낮았다. \circled2 Agar와 casein의 cohesiveness는 control보다 유의하게 높았으며 gelatin은 control보다 유의하게 낮았다. 3. 관능검사나 Instron에 의한 기계적 검사에 있어서 시료의 차이를 가장 잘 구분해 주는 특성치는 hardness라고 생각되어진다

• 원예과학기술지
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• 제30권2호
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• pp.201-207
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• 2012

본 연구는 딸기 소식물체의 급속대량 증식을 위한 기내배양에서 적정한 지지물과 최적의 MS 배지 이온강도를 구명하기 위해 수행되었다. 딸기($Fragaria$ $ananassa$ 'Houkouwase') 절편체는 지지물로 agar와 Tosilee(상업적 플러그 육묘용 배지) 배지를 사용하고, 공급된 MS 배지는 기본 MS(대조구), 1/2 MS, 1/4 MS의 강도로 공급하여 자가영양배양 하에서 미세증식하였다. Agar 배지에서 생육을 비교했을 때 1/2 MS 강도에서 초장과 근장이 가장 길었다. 또한 1/2 MS 강도에서 지상부 생체중과 건물중, 그리고 엽면적이 1/4 MS와 기본 MS 강도에서보다 우수했다. 기본 MS의 Tosilee 배지에서 딸기 소식물체를 배양했을 때 초장, 근장, 지상부와 지하부의 생체중과건물중이 agar 배지에서 배양했을 때보다 더 양호했다. 자가영양배양을 통한 기내미세번식 딸기 소식 물체는 1/2 MS 강도의 agar 배지에서 배양하기보다는 기본 MS 강도의 토실이배지에서 가장 우수한 생육을 나타냈다.

• 한국식생활문화학회지
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• 제23권4호
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• pp.499-506
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• 2008

This study was conducted to determine the quality characteristics of grape jellies for the elderly. The jellies contained sugar (control) or sugar derivative sweeteners (erythritol, isomaltooligosaccharide, sorbitol, and xylitol). Agar (0.31%) and $\kappa$-carrageenan (0.27%) were the gelling agents. The average age of the subjects participating in the acceptance test was 79. The lightness (L), redness (a), and yellowness (b) values of the agar gel with erythritol mostly decreased, indicating a darker and pale red color. The L and b values of the carrageenan gel with sugar derivative sweeteners increased, indicating brighter and yellowish color. The agar and carrageenan gels with sorbitol showed higher gelling and melting temperature, indicating that gelation occurred easily and did not easily melt. The agar and carrageenan gels with xylitol showed a low-melting temperature, indicating low stability with temperature change. The break-down rate of the agar and carrageenan gels with erythritol was low, whereas that of agar gel with sorbitol was relatively high despite its high melting temperature. Hardness, cohesiveness, gumminess, and chewiness of the gels with sugar derivative sweeteners decreased, and this tendency was most distinct with isomaltooligosaccharide in the agar gel and with sorbitol in the carrageenan gel. The rupture properties of the gel were the same as the hardness of the gel. Sensory acceptance of the agar gels with erythritol, sorbitol, isomaltooligosaccharide, and the carrageenan gel with erythritol was fairly high, whereas that of the agar gel with xylitol and the carrageenan gel with isomaltooligosaccharide and xylitol was low. The results show that sorbitol and erythritol are appropriate as sugar substitutes in grape jellies for the elderly about the acceptability and stability of the gels.

• Journal of Microbiology and Biotechnology
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• 제18권3호
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• pp.579-584
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• 2008

A commercial chromogenic agar medium (DFI) was supplemented with glucose (mDFI) to enhance the specificity of Enterobacter sakazakii (E. sakazakit) detection. Escherichia vulneris (E. vulneris), a putative false-positive strain on the DFI medium, produces ${\alpha}$-glucosidase. The enzyme ${\alpha}$-glucosidase hydrolyzes a substrate, 5-bromo-4-chloro-3-indolyl-${\alpha}$, D-glucopyranoside $(X{\alpha}Glc)$, producing green colonies. E. sakazakii strains produced green colonies on both DFI and mDFI agar, whereas E. vulneris produced green colonies on DFI agar but small white colonies on mDFI agar. E. sakazakii and E. vulneris were also readily differentiated by colony color when the mixed culture of the two strains was plated on mDFI agar and incubated for 24 h at $37^{\circ}C$. The results indicate that the selectivity of the commercial chromogenic agar medium could be improved by a simple supplementation with glucose.