• 한국미생물·생명공학회지
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• 제9권2호
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• pp.77-82
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• 1981

Candide tropicalis was selected for its ability to utilize spent waste generated by the alcohol distillery using tapioca starch as a raw material. Optimum pH and temperature on batch culture of the organism were 4.0 and 3$0^{\circ}C$. The growth of the organism was markedly increased when 0.2% of ammonium sulfate, 0.002% of potassium phosphate dibasic, add 0.04% of magnesium sulfate were supplemented to the filtrate. At these conditions, maximum specific growth rate and saturation constant were 1.0 hr$^{-1}$ and 4.4 g.1$^{-1}$ , respectively. At a dilution rate of 0.5hr$^{-1}$ , a productivity of 1.84 g.1$^{-1}$ . hr$^{-1}$ was obtained and about 70% of carbohydrate was assimilated. Protein content of dried cell was about 60%.

• 한국식품과학회지
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• 제31권5호
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• pp.1315-1323
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• 1999

Automated turbidometer, Bioscreen(Labsystem)을 이용하여 tryptic soy broth에 에탄올(3%, 5%. 7%(v/v)) 및 유기산( 초산, 구연산 .젖산, 피로피온산 및 주석만(W/V))을 단독으로 첨가하거나, 혼합하여 Staphylococcus aureus, Salmonella typimurium, Escherichia coil O157 : H7, Listeria monocytogenes의 증식 곡선의 면적(AREA)과, 최대성장율(MGR), MGT(minimum generation time), DT(detection time)를 조사하였다. 모든 균주는 7% 에탄올에서 24 시간 동안 전혀 증식하지 못했으나 0.1% 유기산에서는 미생물의 종류와 유기산의 종류에 따라 다양한 양상을 보였다. S. aureus의 경우 프로피온산이 뚜렷한 증식 저해 효과를 나타내었으며, S. typhimurium의 경우 초산이 비교적 높은 효과를 보였다 L. monocytogenes에 대해서는 프로피온산, 주석산 및 젖산이 뚜렷한 증식 저해 효과를 보인 반면, E. coil O157 : H7의 경우에는 초산과 프로피온산이 효과가 있었다. 1%· 에탄올과 0.01% 유기산을 병용했을 때 S. typhimurium은 AREA에서 2% 에탄올 및 0.05% 초산의 증식 저해율과 비슷한 효과를 보였으며, L. monocytogenes는 AREA에서 0.05%프로피온산 및 MGR, MGT, DT에서 2% 에탄올과 비슷한 저해율을 보였다. S. aureus은 0.01% 프로피온산을 단독으로 사용했을 때가 오히려 0.01% 프로온피산과 1% 에탄올을 동시에 처리한 경우보다도 월등히 증식 저해 효과를 나타내었으며, E. coil O157 : H7은 1% 에탄올과 0.01% 유기산을 동시에 사용해도 AREA를 제외하고는 증식 저해를 받지 않았다.

• Journal of Ginseng Research
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• 제7권2호
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• pp.102-107
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• 1983

The effects of saponin, one of major components (Panax ginseng C.A. Meyer), on the growth of E. coli K-12 and the formation of siderphore was observed The following results were obtained. 1. When E. coli was grown on medium containing 1${\times}$10-5%-11${\times}$10-1% of the saponin, the rate of growth was stimulated at 10-1% of the saponin significantly compared to that of control. 2. When E. coli K-12 was grown on medium containing 1${\times}$10-1% of the saponin, the amount of siderphore was two times as much as the control. 3. The growth of E. coli was observed to be dependent on the concentration of siderophore when siderophore was added to medium. 4. The effect of saponin on the formation of siderophore in vitro was observed to reach maximum at 1${\times}$10-3% of the saponin. Such results suggest that the growth rate of E. coli K-12 could be enhanced by ginseng saponin fraction through stimulation of siderphore formation. We have described the fast growth of E. coli, K-12 and B. subtilis, rapid uptake of 14C-glucose, and high level of other metabolites such as lipids and proteins of E. coli, and B. subtilis in medium containing saponing fraction compared to that of microorganisms without saponin fraction.1∼3Such differences were claimed to be due to rapid uptake of 14C-glucose by widened periplasmic region throught unknown mechanism in the prescence of saponin fraction in medium3 and have raised a question whether there is another possible factor, siderophore4(Greek for iron bears), since microorganisms must secure a sufficient amount of iron for normal growth. These are known to be synthesized by the cells under iron-deficient condition and in most case, excreted into the medium5, where they can complex and solubilize any iron present there. It is generally believed that these complexes are then taken into the cells presumably by specific transport systems, thus providing iron for cell metabolism. Within the group of enteric bacteria, only three species (E. coli, S. typhimurium, and A. aerogense) have, so far, been studied in a ny detail. The main iron-binding compound produced by these species is enterochelin, and its role in iron transport is now well established. And biosynthesis of enterochelin from 2, 3- dihydroxybenzoate and serine in the prescence of magnesium ions and ATP was reported6. 2, 3-dihydroxybenzoate was also shown to involve isochorismate and 2, 3-dihydro-2, 3-dihydroxybenzoate as intermediate.7∼11 The present paper deals with the effect of ginseng saponin fraction on growth, the level of enterochelin formation in vivo and the conversion of 2, 3-dihydroxybenzoate and serine into entrochelin in vitro, and entrochelin obtained on the growth in relation to possible explanation of ginseng saponin fraction on the rapid growth of E. coli, K-12.

• 한국식품과학회지
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• 제37권5호
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• pp.850-855
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• 2005

본 연구는 냉장돈육에서의 식중독 원인균이면서 냉장온도에서 성장이 가능한 병원성균인 L. monocytogenes에 대한 적절한 위생관리를 제시하기 위하여 포장돈육 작업장 원료돈육에서 분리된 야생균주 L. monocytogenes 이용하여 돈육포장공정 및 유통조건에서의 L. mnocytogenes에 대한 성장예측모델을 제시하고자 실시하였다. 성장실험은 온도 5, 10, 15, $20^{\circ}C$ 시간은 0, 1, 2, 3, 18, 48, 120시간에서 실시하였으며, 이를 바탕으로 온도별 Gompertz value인 A, C, B, M의 값과 Growth kinetic인 exponential growth rate(EGR), generation time(GT), lag phase duration(LPD), maximum population density(MPD)를 산출하였다. GT, LPD는 온도가 상승할수록 그 값이 점점 낮아지는 경향을 나타났으며, EGR의 경우는 반대로 온도가 높아질수록 점점 높아지는 경향을 나타냈다. Gompertz value중 B와 M 값을 이용하여 온도를 주요 control factor로 선정한 반응표면분석(Response surface analysis)을 실시하여 온도에 따른 다항식을 산출하였고 이 식을 Gompertz 식에 적용하여 온도와 시간에 따른 냉장돈육에서의 L. monocytogenes에 대한 성장정도를 예측할 수 있는 성장예측모델을 제시하였다. 개발된 성장예측모델에 대한 검증은 GT, LPD, EGR에 대한 실험값과 예측값의 비교를 통하여 실시하였으며, 그 결과 GT, LPD, EGR 모두 통계적으로 유의하게 나타났다(p<0.01). 따라서 이 모델은 risk assessment 중 exposure assessment를 위한 성장예측모델로 충분히 이용가능 한 것으로 보이며, 추후 냉장돈육 위성관리기준에 대한 과학적 근거자료로 활용될 수 있을 것으로 보인다.

• 한국환경과학회지
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• 제6권5호
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• pp.481-488
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• 1997

Microorganisms capable of degrading trlchloroethylene(TCEI using phenol as a induction substrate were isolated from industrial effluents and soil. The strain MS-64K which had the highest blodegradablllty was identified as the genus Micrococcus. The optimal conditions of medium for the growth and blodegadatlon of trlchloroethylene were observed as follows; the initial pH 7.0, trlchloroethylene 1, 000ppm as the carbon source, 0.2% ${(NH_4)}_2SO_4$, as the nitrogen source. respectively. Lag period and degradation time on optimal medium were shorter than those on Isolation medium. Growth on the optimal medium was Increased. Addition of 0.1% Triton X-100 Increased the growth rate of Micrococcus sp. MS-64K, but degradation was equal to optimal medium. Trlchloroethylene degradation by Micrococcus sp. MS-64K was shown to fit logarithmic model when the compound was added at initial concentration of 1, 000ppm.

• 한국토양비료학회지
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• 제46권6호
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• pp.673-680
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• 2013

Phosphorus accumulating microorganisms (PAOs) are influenced by various environmental factors and heavy metals. This study was performed to evaluate the effects of the selected heavy metals on the growth and phosphorus removal capacity of Bacillus sp. 3434 BRRJ, Pseudomonas aerunogisa, and Bacillus Subtilis, well known as PAOs. The heavy metals used in this study included Cu, Cd, As, and Zn. The $IC_{50}$ (median inhibition concentration) values of Bacillus sp. 3434 BRRJ for the Cu, Cd, As, and Zn were 8.07 mg $L^{-1}$, 0.18 mg $L^{-1}$, 73.62 mg $L^{-1}$ and 0.25 mg $L^{-1}$, respectively. The $IC_{50}$ values of Pseudomonas aerunogisa for the Cu, Cd, As, and Zn were 4.45 mg $L^{-1}$, 0.16 mg $L^{-1}$, 18.51 mg $L^{-1}$ and 2.34 mg $L^{-1}$, respectively. The $IC_{50}$ values of Bacillus Subtilis for the Cu, Cd, As, and Zn were 3.81 mg $L^{-1}$, 0.18 mg $L^{-1}$, 11.31 mg $L^{-1}$ and 0.47 mg $L^{-1}$, respectively. The phosphorus removal efficiencies of the three bacteria, Bacillus sp. 3434 BRRJ, Pseudomonas aerunogisa, and Bacillus subtilis were 93.12%, 71.81%, and 65.31%, respectively. Based on the results of the three PAOs obtained from the study, it appears that Bacillus sp. 3434BRRJ may have the best results in terms of their growth rate and P removal efficiencies.

• 한국식물병리학회지
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• 제11권4호
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• pp.292-297
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• 1995

We developed an in vitro assay method for evaluating plant growth promotion and providing an evidence that the growth promotion is rendered by growth enhancing factors. The amendment of culture filtrates of Trichoderma harzianum T95 and Gliocladium virens G872 and G872B in Murashige and Skoog (MS) agar medium enhanced the cotyledon growth of cucumber in terms of fresh weight and primary leaf area of cucumber cotyledon cuttings, of which the treatment of G. virens G872B was the most effective. The mycelial culture filtrate of G872B was more effective in the growth promotion than its conidial germling filtrate. The addition of 1% sucrose in MS mineral medium with 0.1% culture filtrates of the antagonists (T95 and G872B) was optimum for enhancing the effect of the filtrates on the growth of cotyledon cuttings in vitro. When cucumber seeds treated with G872B, Pseudomonas putida Pf3 or the G872B-Pf3 mixture were planted in a greenhouse, the rate of seed germination, biomass of shoot and root, and yield of cucumber fruits were increased, especially by G872B or the G872B-Pf3 mixture. Correspondingly, cucumber fruit yields in early to middle-cycles of harvest were significantly greater in the plots of G872B than the control and Pf3-treated plots, and the final yield was highest in the plots of the G872B-Pf3 mixture applications.

• 한국환경과학회지
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• 제24권1호
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• pp.17-23
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• 2015

This study was aimed to determine the effect of basal application of Effective Microorganisms (EM) on the grow and yield of cucumber. For treatments, the EM was applied to soil with fertilizer composed with $N-P_2O_5-K_2O$-manure (24.0-16.4-23.8-2,000kg) in the 1.0 strength (defined as EM+1S), 2/3 strength (defined as EM+2/3S), 1/2 strength (defined as EM+1/2S), without fertilizer (defined as EM), or only fertilizer in the 1.0 strength (defined as 1S). In result, there was no significant differences of organic substance content and pH with the EM treatment. While the EC (Electric conductivity) concentration was decreased, plant-available P (phosphorus) was markedly increased. Chlorophyll content was highest in the treatment of EM+standard application rate for both semi-forcing and retarding culture. In contrast, no significant difference was found in plant height and internode length under the fertilizer treatment. Weekly harvested number of cucumber was highest at the treatment of EM+standard application for the semi-forcing culture, while it was 3.6 at the EM+1/2 application for the retarding culture. Weekly yield was greatest at the EM+standard application treatment and decreased with the decrease of fertilizer application rate. In addition, weekly yield was significantly reduced in the treatment of EM. There was no significant difference in yields by production time with the fertilizer applications?. Yield was increased with temperature for the semi-forcing culture, while consistent pattern was maintained for the retarding culture.

• Asian-Australasian Journal of Animal Sciences
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• 제12권1호
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• pp.139-147
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• 1999

Peptides are formed in the rumen as the result of microbial proteinase activity. The predominant type of activity is cysteine ptoteinase, but others, such as serine proteinases, are also present. Many species of protozoa, bacteria and fungi are involved in ptoteolysis; large animal-to-animal variability is found when proteinase activities in different animals are compared. The peptides formed from proteolysis are broken down to amino acids by peptidases. Different peptides are broken down at different rates, depending on their chemical composition and particularly their N-terminal structure. Indeed, chemical addition to the N-terminus of small peptides, such as by acetylation, causes the peptides to become stable to breakdown by the rumen microbial population; the microorganisms do not appear to adapt to hydrolyse acetylated peptides even after several weeks exposure to dietary acetylated peptides, and the amino acids present in acetylated peptides are absorbed from the small intestine. The amino acids present in some acetylated peptides remain available in nutritional trials with rats, but the nutritive value of the whole amino acid mixture is decreased by acetylation. The genus Prevotella is responsible for most of the catabolic peptidase activity in the rumen, via its dipeptidyl peptidase activities, which release dipeptides rather than free amino acids from the N-terminus of oligopeptides. Studies with dipeptidyl peptidase mutants of Prevotella suggest that it may be possible to slow the rate of peptide hydrolysis by the mixed rumen microbial population by inhibiting dipeptidyl peptidase activity of Prevotella or the rate of peptide uptake by this genus. Peptides and amino acids also stimulate the growth of rumen microorganisms, and are necessary for optimal growth rates of many species growing on tapidly fermented substrates; in rich medium, most bacteria use pre-formed amino acids for more than 90% of their amino acid requirements. Cellulolytic species are exceptional in this respect, but they still incorporate about half of their cell N from pre-formed amino acids in rich medium. However, the extent to which bacteria use ammonia vs. peptides and amino acids for protein synthesis also depends on the concentrations of each, such that preformed amino acids and peptides are probably used to a much lesser extent in vivo than many in vitro experiments might suggest.

• 농업과학연구
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• 제47권1호
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• pp.193-204
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• 2020

This experiment was conducted to study the effect of organic fertilizer on the growth of Peucedanum japonicum Thunberg and the change of soil chemical characteristics. The organic matter contents of coffee sludge and dried food waste powder were 44.26 and 51.18%, respectively. These values exceed the organic matter content of organic fertilizers recommended by the Rural Development Administration (RDA) of South Korea by more than 30%. Accordingly, they indicate the possibility of their use as organic fertilizers. The results from the analysis of soil properties after cultivation showed that the organic matter content of coffee sludge amended soils was two-fold higher than that of dried food waste powder amended soils. However, the content of available phosphorus was two times lower in the coffee sludge amendments. It is expected that the dried food waste powder was actively used to decompose organic substances, and that phosphoric acid was added by the soil microorganisms used to decompose organic substances. In terms of Peucedanum japonicum Thunberg growth, leaf discoloration was observed for all treatments except with the standard rate of dried food waste powder. The standard rate of dried food waste powder also produced relatively better results than other treatments with regard to other growth characteristics such as root length (34.08 cm), root diameter (0.78 cm), and fresh root weight (4.77 g plant^-1). Therefore, the standard rate of dried food waste powder produced better results than other treatments and can be used as an organic fertilizer in the growth of Peucedanum japonicum Thunberg.