• 한국조리학회지
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• 제4권
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• pp.413-436
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• 1998

In order to guarantee the safety of Korean Naeng Myon Broth in summer, pH and micrological quality of iced noodle gravy which is cooked and sold in public restaurant were investigated. And the variations of pH, taste and microorganism were studied with organic acid treatment during storage period. The micrological status of iced noodle gravy showed that average number of total aerobic bacteria was 2.7${\times}$105CFU/$m\ell$ and fecal coliform was 8.3${\times}$103CFU/$m\ell$ respectly. Food poison microorganisms not detected and average of pH was 4.8. pH changed slightly during storage period and deceased with increasement of organic acid added. Sour taste of organic acid increased acetic acid, citric acid, lactic acid order and there was no organic acid having with more sour taste than iced noodle gravy which is cooked and sold in public restaurant. Salmonella was destroyed when treated with 1% of acetic acid and lactic acid and Escherichia coli became extinct at treatment with 0.8% acetic acid and 1% lactic acid. in case of same concentration, inhibition effects to Escherichia coli multiplication show citric acid, lactic acid, acetic acid order. In conclusion, treatment with more than 0.8% acetic acid and above 1.0% lactic acid or more than 1.0% citric acid in case of production and consumption a day can prevent from Escherichia coli pollution in Korean Naeng Myon Broth.

• 한국토양비료학회지
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• 제49권5호
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• pp.461-468
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• 2016

One of the important phytohormones produced by plant growth promoting bacteria is the auxin; indole-3-acetic acid (IAA), with L-tryptophan as the precursor. In this study, we focused on the investigation of optimal conditions for the production of IAA by Bacillus megaterium BM5. We investigated culturing conditions, such as incubation temperature, pH of the culture medium and incubation period, with varying media components such as inoculation volume, tryptophan concentration and carbon and nitrogen source. Besides, optimization study intended for high IAA production was carried out with fermentation parameters such as rpm and aeration. The initial yield of $42{\mu}g\;IAA\;ml^{-1}$ after 24 hr increased to $85{\mu}g\;ml^{-1}$ when 5% (v/v) of L-tryptophan was used in the culture broth. The maximum yield of $320{\mu}g\;IAA\;ml^{-1}$ was observed in trypticase soy broth (TSB) supplemented with starch and soybean meal as C and N sources with a C/N ratio of 3:1 (v/v) at $30^{\circ}C$, pH 8.0 for 48 hrs with 1.0 vvm and 250 rpm in 5 L working volume using 10 L scale fermenter. The bacterial auxin extracted from the culture broth was confirmed by thin layer chromatography and high-performance liquid chromatography and effect on plant growth was confirmed by root elongation test.

• Mycobiology
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• 제43권3호
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• pp.266-271
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• 2015

Several types of yeasts were isolated from wild flowers around Jangseong Lake in Jeollanam-do, Republic of Korea and identified by comparing the nucleotide sequences of the PCR amplicons for the D1/D2 variable domain of the 26S ribosomal DNA using Basic Local Alignment Search Tool (BLAST) analysis. In total, 60 strains from 18 species were isolated, and Pseudozyma spp. (27 strains), which included Pseudozyma rugulosa (7 strains) and Pseudozyma aphidis (6 strains), was dominant species. Among the 60 strains, Bullera coprosmaensis JS00600 represented a newly recorded yeast strain in Korea, and its microbiological characteristics were investigated. The yeast cell has an oval-shaped morphology measuring $1.4{\times}1.7{\mu}m$ in size. Bullera coprosmaensis JS00600 is an asporous yeast that exhibits no pseudomycelium formation. It grew well in vitamin-free medium as well as in yeast extract-malt extract broth and yeast extract-peptone-dextrose (YPD) broth, and it is halotolerant growing in 10% NaCl-containing YPD broth.

• 약학회지
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• 제37권1호
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• pp.1-8
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• 1993

A procedure for the high-performance liquid chromatographic determination of Nebramycin factors in fermentation broth of Streptoalloteichus hindustanus ATCC 31218 mutant was investigated using pre-column derivatization and LTV detection. The method is based on pre-column derivatization of Nebramycin factors with 2,4-dinitrofluorobenzene(DNFB) in the presence of Tris (hydroxymethyl)aminoethane. The chromatographic separation of derivatives of Nebramycin factors and unknown impurities is achieved using reversed-phase column (NOVA-PAK $C_{18}$, Waters Co.) and AcCN : H$_{2}$O : AcOH (53.0:46.5:0.5) as a mobile phase. The mixture of these derivatives were separated within 35 minutes and the optimum wavelength($\lambda_{max}$ ) of the UV detector was 353 nm. The linearity of response for derivatives of Nebramycin factors is demonstrated for concentrations up to 500 $\mu\textrm{g}$/ml and the relative standard deviation is less than 0.79%. Detection limit was 1.67 ng for the 10 $\mu\textrm{l}$ sample volume employed.

• The Korean Journal of Physiology
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• 제5권1호
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• pp.15-18
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• 1971

The effects of ginseng on the penetration of glucose into Saccharomyces cerevisiae were studied by determining the amount of glucose in the supernatant of the glucose broth medium in which some dose of water extracts of ginseng or saponin were added and the yeast was cultured for 1 hour. 1. In the 1 hour culture with 0.04%, 0.08%, 0.16%, 0.32% and 0.64% dry ginseng glucose broth medium, the penetration rate of glucose into yeast was increased 4.76%, 7.96%, 10.09%, 9.08% and 7.48% respectively. 2. In the 1 hour culture with $10^{-6}%,\;10^{-5}%,\;10^{-4}%,\;10^{-3}%,\;and\; 10^{-2}%$ of saponin glucose broth medium, the penetration rate of glucose into yeast was increased 3.05%, 6.57%, 5.595, 4.44%. and 2.87% respectively. 3. Since the highest increasing percentage of penetration of ginseng and saponin were 10.19% and 5.89% respectively, the increasing rate of the ginseng was about twice that of the saponin. Therefore it could be concluded that the saponin contained in ginseng and other unkown components of ginseng affect the cell permeability.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.726-731
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• 1999

It was discovered that ammonium phosphate in the medium played an important role in both growing mycelium and producing exopolysaccharides (EPS) from G. lucidum. In lower concentration levels of ammonium phosphate (0-3 g/l), an improved mycelial growth was observed by maintaining more filamentous morphology than in high concentrations (5-11 g/l). In addition, it was confirmed by comparing the factual dimension and frequency of the area regarding the mycelial pellets. This must be attributed to limitations of nutrient transfer by maintaining filamentous mycelium during the cultivation in a low ammonium phosphate containing medium. On the other hand, the best EPS production was observed in medium with the absence or low concentration of ammonium phosphate. The shear stress of the culture broth was greatly affected by the shear rate, as compared with that of the culture broth with high ammonium phosphate concentration. The rheological characteristics of the fermentation broth and filtrate worked well according to the Herschel-Bulkley model. It was also found that the morphological changes of the mycelium resulting from the ammonium phosphate concentration directly affected the rheological characteristics of the system and resulted in reversely affecting the EPS production levels. Based on these results, it can be concluded that delicate regulation of the ammonium phosphate concentration in the culture media should be provided in order to obtain optimal mycelial growth and/or EPS production.

• 한국미생물·생명공학회지
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• 제42권1호
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• pp.67-72
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• 2014

A new substrate, breadcrumbs, was investigated for biomass accumulation, the pH of the cultural broth, the formation of primary metabolites such as the proteins and endopolysaccharides of Schizophyllum commune 1768 and Trametes versicolor 353, as well as its bioconversion efficiency. The results showed that S. commune gives more mycelial mass ($23.96{\pm}0.8g/l$) and in a shorter period (4 days) than T. versicolor ($15.76{\pm}0.5g/l$ in 5 days). The pH values changed from the initial 6.1 to 3.6 in S. commune cultural broth and to 4.4 in T. versicolor cultural broth. Maximal endopolysaccharide content in the mycelia of S. commune and T. versicolor were 7.13% and 6.42%, correspondingly. Crude protein content in S. commune mycelium was 18.83 % on the 4th day of cultivation, and 20.03%, in the mycelium of T. versicolor, on the 6th day of cultivation. Kinetic parameters for the quantitative estimation of cultivation efficiency were calculated for biomass, endopolysaccharide, and crude protein concentrations.

• 한국식품영양과학회지
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• 제20권2호
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• pp.179-186
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• 1991

Aspergillus fumigatus IFO 5840을 공시균주로 하여 cytosine deaminase의 생성 최적조건을 밝히기 위하여 각종 탄소원, 질소원과 같은 영양소 및 배양 온도, 초기 pH, 배양시간, 통기성의 영향을 조사하였다. 본 공시균의 cytosine deaminase의 생성을 위한 최적 배지의 조성은 2% 포도당, 1% 효모추출물로, 배지의 초기 pH는 8.5이었다. 배양 최적 조건은 $30^{\circ}C$에서 28시간 진탕 배양이 양호했다. 이러한 최적조건에서 500ml 용량의 진탕 flask에 배지 100ml를 넣었을때 효소생성이 최고에 달하였다. 공시균주의 세포내 효소의 생성이 무기질소원에 의해 억제 되었으나 유기질소원인 yeast extract에 의해서는 촉진되었다.

• 한국응용곤충학회지
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• 제48권3호
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• pp.385-392
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• 2009

Xenorhabdus nematophila (Xn)와 Photorhabdus tempeerata subsp. temperata (Ptt)의 곤충병원세균을 배추좀나방(Plutella xylostella)의 혈강에 주입할 경우 높은 병원력을 보였다. 본 연구는 이들 세균 배양액의 섭식 처리에 따른 배추좀나방에 대한 병원성 유기를 조사하였다. 세균 배양액만을 이용하여 배추좀나방 3령충에 섭식 처리한 결과 뚜렷한 병원성을 유발하지 못하였으나, Bacillus thurigiensis(Bt) 와 혼합 처리하였을 때 높은 Bt 병원성 제고 효과를 나타냈다. 물질 추적을 위해서 이 세균 배양액을 유기 용매를 이용하여 헥산, 에틸아세테이트 및 수용액 추출 분획구로 분리하였다. 대부분이 Bt 상승효과는 에틸아세테이트 추출 분획구에서 나타났다. Thin layer chromatography 분석 결과는 에틸아세테이트 분획구가 대사물질을 포함하고 있으며, 이들이 헥산 또는 수용액 추출 분획구에 포함된 물질과는 상이하다는 것을 나타냈다. 이러한 결과는 이들 곤충병원세균이 Bt 병원성을 제고시키는 물질을 생산하고 배양액으로 분비한다고 제시하고 있다.

• 한국약용작물학회지
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• 제15권3호
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• pp.162-169
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• 2007

여러 가지 추출조건을 통해 얻은 오미자 추출물과 전통발효공정을 통해 얻은 오미자 발효액의 면역증진 활성을 비교하였다. 오미자 발효액이 B cell과 T cell에서 시료를 첨가하지 않은 대조군과 비교하여 각각 30%와 22%이상의 수치를 나타내며 가장 좋은 활성을 나타내었다. B, T cell의 cytokine 분비량 측정을 통한 실험에서도 오미자의 전통발효액이 생육증진과 유의적으로 가장 많은 분비량을 나타내었다. 대식세포를 이용한 NO$^-$ 생성능 측정에서 오미자 발효액 및 추출물의 활성이 LPS와 비교해 비슷하거나 높은 것을 확인하였다. 또한 시료를 LPS와 같이 첨가하였을 때 시료만을 첨가했을 때보다 높은 활성을 나타내어 농도에 따른 유의적 활성 증가가 이루어질 것으로 사료된다. NK cell의 활성측정에서 모든 시료 조건에서 6일 동안 생육이 증가하였으며 오미자 발효액을 첨가한 것이 아무것도 첨가하지 않은 대조군과 비교하여 약 1.4배의 생육도 증진을 나타내어 1.2배의 생육도 증진을 보인 100$^{\circ}$C에서 초음파를 병행한 물 추출물보다 높은 활성을 나타내었다. HPLC를 이용한 추출물들의 성분 분석에서 전통발효 공정을 통해 추출공정에서 확인할 수 없었던 특정 성분의 생성 및 기존 성분의 용출 증진이 이루어지는 것을 확인하였고, 이에 따라 면역활성의 증진이 이루어지는 것으로 추정할 수 있었다. 이상의 결과에서 오미자는 면역활성을 가지는 성분을 함유하고 있으며 전통발효 공정을 통해 생성되는 대사산물이 면역실험에서 유효활성 증진을 나타내는 것을 확인하였다. 이는 전통발효 공정을 통해 생성된 성분의 활성으로 세포독성이 감소하고 세포활성이 증가하기 때문인 것으로 생각된다. 이상의결과는 기존에 면역활성 증진 효과를 나타내는 초음파병행 공정 보다 높은 증진 효과로 전통발효 공정 및 활성성분에 대한 다각적인 연구가 필요할 것으로 사료된다.