• Korean Journal of Food Science and Technology
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• v.48 no.3
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• pp.214-222
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• 2016

This study was performed to increase the production of ${\gamma}$-aminobutyric acid (GABA) by lactic acid bacteria (Lactobacillus brevis CFM11) and manufacture an optimum medium using the sap from Darae (Actinidia arguta). The concentration of GABA in the fermented sap was determined using GABase enzymatic assay. The isolated L. brevis CFM11 produced $605.67{\mu}g/mL$ GABA after incubation for 24 hours at $37^{\circ}C$ in broth. The sap was fermented by L. brevis CFM11 under optimum conditions of $32^{\circ}C$ for 48 hours with 40% rice bran extract, 1.0% sucrose, 3.0% soytone, 0.2% magnesium sulfate, and 0.2% MSG. The fermented sap produced a concentration of $1366.13{\mu}g/mL$ GABA. These results demonstrate that fermenting Darae sap using L. brevis CFM11 can produce a fermented sap beverage with increased GABA content.

• Journal of Bio-Environment Control
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• v.8 no.2
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• pp.83-89
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• 1999

Butterhead lettuce was grown hydroponically in a plant factory during summer season. To decrease the occurrence of tipburn and increase productivity, optimum cultivars, substrates, gully slope and height, and the amount of irrigation were evaluated in this experiment. Cultivars ‘Rex’ and ‘Flandria’ showed higher productivity with less tipburn as compared to the others in spite of lower growth rates and appeared to be suitable cultivars during summer season. Cocopeat showed high productivity due to superior physio-chemical characteristics. Appropriate gully slope which makes nutrient solution easy to flow was shown to be 1 to 2%. The amount of irrigation was appropriate at 2$\ell$/gully. Higher growth of the butterhead lettuce observed when the bed was at a lower position. Low bed was thought to be good for lettuce growth with proper humidity and average temperatures.

• The Korean Journal of Mycology
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• v.10 no.2
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• pp.75-83
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• 1982

As a primary study for cell growth and alcohol production of a cider yeast, Saccharomyces sp. R-11, cultural and nutritional characteristics of the strain were investigated. The results obtained were as follows: The optimum culture medium for this strain was a synthetic medium, Henneberg B, and sucrose was the best carbon source for yeast growth and alcohol production. Optimum sugar concentrations for yeast growth and alcohol production were 15% and 25%, respectively. Optimum pH and temperature of the basal medium for growth of this strain were 4.5 and $30^{\circ}C$ respectively. The yeast growth was enhanced by the addition of 100 ppm of $Mg^{2+}$, but significantly inhibited by the addition of 100 ppm of $Co^{2+}$. Lower temperature and maintenance of optimum pH for yeast growth increased the final alcohol concentration. Under optimum condition for cell growth at stationary culture, generation time and specific growth rate of the strain were 7.5 hr and 0.092 $hr^{-1}$, respectively. At 8% initial alcohol concentration, yeast growth was inhibited about 50% and this strain could not be grown at more than 12% initial alcohol. The strain could be grown at less than 125ppm $SO_2$without alcohol addition, and at less than 75 ppm $SO_2$ with 8% initial alcohol. The higher sulfur dioxide concentration of a medium, the longer lag phase in yeast growth was observed. This strain could induced alcoholic fermentation at less than 10% initial alcohol concentration with 0 and 25 ppm $SO_2$, at less than 8% initial alcohol with 50 and 75 ppm $SO_2$, and at less than 6% initial alcohol with 100 and 125 ppm $SO_2$.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.46-46
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• 2022

본 연구의 목적은 약용과 식용으로서의 활용도가 높은 일당귀[Angelica acutiloba (Siebold & Zucc.) Kitagawa]의 GA₃농도에 따른 생육특성을 확인하고, 최적의 재배기술 개발 및 지속가능한 안정적인 작물생산에 대한 기초자료의 제공에 있다. 연구재료는 강원도 태백시에 위치하는 일당귀 재배농가에서 2021년 10월에 채종한 종자를 구입하였고, 영주시 풍기읍에 위치한 연구온실에서 연구를 수행하였다. 일당귀의 종자를 증류수에 48시간 침지 후 GA₃농도 4조건(50 ppm, 100 ppm, 500 ppm, 1,000 ppm)에 24시간 처리 후 72구 포트에 파종 후 출아율과 생육특성을 조사하였다. 연구결과 일당귀 종자는 16일이 경과한 시점부터 출아를 시작하였고, 500 ppm처리구에서 73.3%로 가장 높은 출아율을 나타냈다. 생육특성조사는 출아 후 40일(1차)과 80일(2차) 경과된 시점에서 총 2회를 수행하였는데 1차 생육조사에서는 주근길이와 직경을 제외한 모든 생육특성에서 처리구별 생육의 차이가 확인되지 않았으나 2차 생육조사에서는 지상부와 지하부의 모든 생육특성에서 처리구별 생육의 차이가 확인되었다. 잎수(6.3개)와 주근길이(4.26 cm)는 500 ppm처리구에서 가장 높은 생육량을 나타냈고, 지상부 높이(21.81 cm), 잎길이(9.0 cm), 잎너비(10.77 cm), 주근직경(5.71 mm)은 1,000 ppm처리구에서 가장 높은 생육량을 나타냈다. 따라서 GA₃ 처리에 따른 일당귀의 생육특성은 생육초기보다 후기로 갈수록 발현량이 높게 나타나는 것으로 판단된다. 또한 저농도의 GA₃처리보다 500-1,000 ppm 사이의 처리농도가 적합한 것으로 판단되며, 추후 일당귀의 유용성분 분석을 통한 이화학적 연구가 추가된다면 최적의 재배기술 확립을 통한 안정적인 작물 생산에 기여할 수 있을 것이라 사료된다.

• Journal of Life Science
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• v.14 no.4
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• pp.608-613
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• 2004

Pyrimidine nucleotide N-ribosidase (pyrimidine 5'-nucleotide phosphoribo (deoxyribo) hydrolase/pyrimidine 5'-nucleoude nucleosidase, EC 3.2.2.10) directly catalyzes pyrimidine 5'-nucleotide to pyrimidine base and ribose (deoxyribo) 5-phosphate. In order to clarify the best nutritional conditions for the growth and the pyrimidine nucleotide N-ribosidase production of Pseudomonas oleovorans ATCC 8062 the effects of various nutrients such as different carbon and nitrogen sources were studied. For the both the growth and the enzyme production, 2% fumarate, 1.5% peptone, 5% corn steep liquor (CSL) and 1% ammonium chloride were excellent carbon and nitrogen sources, respectively. Optimum pH, temperature, and cultivation time for the enzyme production were 7.0, $28^{\circ}C$, and 48 h, respectively. The pyrimidine nucleotide N-ribosidase of P. oleovorans ATCC 8062 was not induced by UMP and its derivatives, and was constitutive enzyme.

• Journal of Life Science
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• v.22 no.10
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• pp.1295-1306
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• 2012

A microorganism producing carboxymethylcellulase (CMCase) was isolated from seawater and identified as Bacillus atrophaeus. This species was designated as B. atrophaeus LBH-18 based on its evolutionary distance and the phylogenetic tree resulting from 16S rDNA sequencing and the neighbor-joining method. The optimal conditions for rice bran (68.1 g/l), peptone (9.1 g/l), and initial pH (7.0) of the medium for cell growth was determined by Design Expert Software based on the response surface method; conditions for production of CMCase were 55.2 g/l, 6.6 g/l, and 7.1, respectively. The optimal temperature for cell growth and the production of CMCase by B. atrophaeus LBH-18 was $30^{\circ}C$. The optimal conditions of agitation speed and aeration rate for cell growth in a 7-l bioreactor were 324 rpm and 0.9 vvm, respectively, whereas those for production of CMCase were 343 rpm and 0.6 vvm, respectively. The optimal inner pressure for cell growth and production of CMCase in a 100-l bioreactor was 0.06 MPa. Maximal production of CMCase under optimal conditions in a 100-l bioreactor was 127.5 U/ml, which was 1.32 times higher than that without an inner pressure. In this study, rice bran was developed as a carbon source for industrial scale production of CMCase by B. atrophaeus LBH-18. Reduced time for the production of CMCase from 7 to 10 days to 3 days by using a bacterial strain with submerged fermentation also resulted in increased productivity of CMCase and a decrease in its production cost.

• Microbiology and Biotechnology Letters
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• v.14 no.5
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• pp.391-397
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• 1986

Three kinds of microoganisms were isolated and identified from the ginseng and ginseng products to research the properties of the molds which spoil the ginseng and ginseng products. The results obtained were as follows: (1) The predominant strains on ginseng products were Aspergillus sp., Penicillium sp.-A and Penicillium sp.-B. These predominant fungi deteriorated ginseng products exclusively, (2) Aspergillus sp. showed the greatest mycelial growth at $40^{\circ}C$ and its optimum pH was 5, meanwhile Pencillium sp. showed the greatest mycelial growth at $30^{\circ}C$ and its optimum pH was 3. (3) The growth of the isolated strains was stimulated with the increase in the concentration of saponin at the lower concentration, meanwhile it was inhibited at 1.0% concentration of saponin.

• Food Science and Preservation
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• v.6 no.2
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• pp.221-227
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• 1999

The immobilized culture system of Saccharomyces cerevisiae was examined to improve the efficiency of vinegar production from persimmon juice. Optimum concentration of Na-alginate for the immobilization was 2%. When the 1eakage of yeast from get beads was checked by turbidity of culture medium with varying concentration of Na-alginate from 1 to 4%, turbidity of culture medium increased from 8 hrs of cultivation with 1% Na-alginate concentration showing optical density of 0.82 at 20 hrs. However, the increase in turbidity of culture medium was slow with 2-4% Na-alginate showing optical density of 0.55-0.58 at 20 hrs. Microscopical analysis of gel matrix showed that the immobilized yeast was grown well regardless of Na-alginate concentration. Optimum size of gel bead and amount of inoculation were 2-3 m and 33mg, respectively. For ethanol production aerobic cultivation for 121hrs using cohen plug followed by anaerobic cultivation using silicon plug equipped with a check valve was the most effective.

• Journal of Mushroom
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• v.15 no.3
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• pp.104-110
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• 2017

In order to determine the possibility of artificial cultivation of Ganoderma lucidum, a study was carried out to optimize the medium composition used for bed culture. Sawdust spawn of medium composition for optimal growth was found to be the combination of 75% oak-sawdust, 10% cotton-seed meal, and 15% beet pulp. The optimal conditions for the formation of fruiting bodies were shown to be a temperature of $28-30^{\circ}C$, light intensity of 1,000-1,500 lux, and $CO_2$ concentration of 1%.

• Applied Biological Chemistry
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• v.48 no.3
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• pp.207-211
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• 2005

The metabolites released from cultures of rhizosphere bacteria can inhibit plant growth. Bacillus subtilis IJ-31 inhibited plant growth by the production of hydrocinnamic acid (HCA). The production of HCA by plant-growth inhibiting rhizobacterium B. subtilis IJ-31 was optimized. $90.5\;{\mu}g/ml$ of HCA was obtained under the condition of 1% rice bran as carbon source, 0.5% tryptone as nitrogen source, 0.1% $ZnCl_2$ as metal source at $37^{\circ}C$ for 60 h (pH 7.0). The optimal condition for the HCA production by B. subtilis IJ-31 in the jar fermenter was established using response surface methodology (RSM) of statistical analysis system(SAS) program. The production of HCA by B. subtilis IJ-31 in the jar fermenter culture reached $102.99\;{\mu}g/ml$ when 2.24% soil extracts was added and agitation speed was 290 rpm under the same condition. And the experimental value of HCA production is $102.5\;{\mu}g/ml$ in the same culture condition. The production of HCA by B. subtilis IJ-31 is higher as 12% than that from the flask culture.