• 한국식생활문화학회지
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• 제2권1호
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• pp.9-16
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• 1987

In early 1956, MSG (monosodium glutamate) had been produced by hydrolysis of the vegetable proteins in Korea. In accordance with development of fermentation technology mainly led by the Japanese scientists, its major production method has been changed to microbial fermentation since 1962. Meanwhile, 5'-ribonucleotides which are nucleic acid-related condiments have been produced by the enzymic hydrolysis of yeast RNA and/or the direct fermentation by Miwon Co. and Cheil sugar Co., respectively since 1977. At the technological viewpoints, Korean fermentation level seems relatively highly-reputated over the world in terms of production yield and unit-consumption level. For further progress of technology, our emphasis on this research area should be laid on both improvement of bacterial strain by means of modern biotechnology and process development through the immobilization and/or computerized control technics, etc.

• 대한미생물학회지
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• 제22권2호
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• pp.185-193
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• 1987

Ten species of herbae, which have been used to treat cancers in Chinese medicine, were tested to investigate their mutagenicity or antimutagenicity in S. typhimurium TA97, TA98, TA100, TA1535, and TA1538. Scolopendra centipede was weakly active in reversion of the frameshift mutation in S. typhimurium TA97 strain and the base-pair substitution in TA100 and TA1535 strains. Other herbae such as Coix lachryma, Dianthus superbus, Tricanthoshse kirilowii, Eupatorium formosanum, Lithospermum erythrorhizon, Ansaema japonicum, Curcuma zedoaria, Helicteres angustifolia, and Euonymus sieboldianus did not show any of the mutagenic potential, regardless of the metabolic activation with rat hepatic microsomal fraction. Dianthus superbus, Eupatorium formosanum, and Euonymus sieboldianus exhibited suppressive activities on microbial mutagenesis of N-methyl-N'-nitrosoguanidine, a base-pair substitution mutagen, in TA1535 and TA100 tester strains. The antimutagenic activities of Dianthus superbus and Euonymus sieboldianus appeared to be dose-dependant.

• Preventive Nutrition and Food Science
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• 제3권2호
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• pp.128-132
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• 1998

7S globulin has been isolate from the defatted soybean meal(glycine max,. merill) by Sepharose-6B column chromatography and CM-Sephadex column chromatography. Coagulum of 7S globulin formed at a temperature of $65^{\circ}C$ in microbial enzyme treatment. In order to characterize the structure of the coagulum, three kinds of coagulum (enzyme-, calcium-and acid-induced coagulum)were compared througth the Scanning Electron Microscope(SEM). The network structure was found to be of two levels. First, there was an appearance on the molecular level in the form of strands. Second, there was a denser network with a fine structure.

• Preventive Nutrition and Food Science
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• 제1권1호
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• pp.53-58
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• 1996

The characterstics of the soy protein curd(eczyme-, HCI- and Ca-surd) were shown by scanning electron micrographs and gel electrophoreis. The emulsion stability of enzyme-curd showed high value in the range of pH 2~10and wide range of temperature(20~8$0^{\circ}C$). While at the isoelectric point(pH5.0), the emulsion stability of the HCI-and Ca-curd was decreased remarkably, and the emulsion stability of temperature was reduced quickly to the 60% and 40% at the 4$0^{\circ}C$. The foam stability of enzyme-curd was slightly higher than that HCI-and CA-curd in all ranges of pH and temperature. The feature of SEM of enzyme-cured produced degradation products faster than that of the HCI- and Ca-curd.

• 한국식품과학회지
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• 제53권3호
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• pp.348-355
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• 2021

Bacteriophages (phages) are known determinants of kimchi microbial ecology. Lactobacillus plantarum is related to kimchi over-acidification during the late stages of kimchi fermentation. A phage infecting Lac. plantarum was isolated from kimchi and characterized. The phage population for kimchi in a market was 2.3 log particles/mL, which corresponded to 32% of the bacterial population on a log scale. The isolated phage was designated as ΦLP12116. ΦLP12116 which belonged to the Siphoviridae family and has a very narrow host range, infecting only Lac. plantarum. The phage was stable at a lactic acid concentration of 1.0% and pH 4.0 at 4℃, indicating that it could survive in kimchi. In the kimchi extract broth treated by the phage, the growth of Lac. plantarum KCCM 12116 was inhibited by 2.2 log CFU/mL compared to the growth in non-phage-treated broth. Therefore, this study suggests that the growth of Lac. plantarum, which is known as an acid-producing strain during late fermentation in kimchi, may be controlled using the phage.

• 한국미생물·생명공학회지
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• 제51권3호
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• pp.325-327
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• 2023

This paper presents the complete genome sequence of a novel marine actinomycete, Streptomyces sp. MMBL 11-1. The genome of Streptomyces sp. MMBL 11-1 was obtained through next-generation sequencing using the PacBio Sequel system and Illumina platform provided by Macrogen, Korea. The assembled genome consists of five contigs, with a total length of 8,496,900 bp and a G+C content of 71.6%. The genome harbors multiple biosynthetic gene clusters (BGCs) associated with producing microbial natural products (MNPs). The comprehensive genomic information of this type of strain will serve as a valuable resource for identifying other marine actinomycetes strains.

• KSBB Journal
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• 제24권1호
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• pp.41-46
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• 2009

식물성 오일은 다양한 생물제품 생산에 적합한 저가의 원료이다. 식물성 오일의 주성분인 oleic acid와 linoleic acid와 같은 불포화 지방산의 함량은 콩기름의 경우 각각 22%와 55%, 옥수수기름의 경우 26%와 60%, 유채기름의 경우 61%와 21%에 달한다. Hydroxy나 keto group으로 치환된 불포화 지방산들은 다른 지방산에 비해 높은 점도와 반응성 등의 특별한 화학적 특성 때문에 가소제, 계면활성제, 윤활유, 세제 등에 사용되는 유용한 산업 화합물이다. 본 연구에서는 Flavobacterium sp. strain DS5 (NRRL B-14859)를 oleic acid로부터 중간생성물로서 10-hydroxystearic acid (10-HSA)를 거쳐 10-ketostearic acid (10-KSA)로의 전환에 이용하였다. 두 개의 생물전환 생성물인 10-KSA와 10-HSA는 GC, GC-MS, $^1H-NMR$, $^{13}C-NMR$을 이용하여 정량 및 정성분석을 수행하였다. 플라스크 배양에서 10-KSA와 10-HSA의 최대 생산량은 각각 3.4 g/L와 0.5 g/L 이었다. 10-KSA 생산을 위한 최적 glucose 농도 yeast extract 농도, oleic acid 첨가시간, 첨가부피는 각각 20 g/L 이하, 5 g/L 이상, 접종 후 18 h, 0.3 ml/50 ml 이었다.

• 한국토양비료학회지
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• 제35권2호
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• pp.118-126
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• 2002

토양의 특성과 재배 환경이 상이한 13개 토양을 대상으로 미생물의 다양성을 분석하여 토양 환경별 미생물상 지표의 기준을 설정하기 위해서 실험한 결과는 다음과 같다. 희석 평판법에 의한 토양별 미생물의 군집은 호기성 세균은 $2{\sim}27{\times}10^6$, 형광성 Pseudomonas는 $1{\sim}1364{\times}10^5$, 그람 음성 세균은 $1{\sim}126{\times}10^4$, 중온성 Bacillus는 $1{\sim}110{\times}10^5$ 범위로 토양간에 현저한 차이를 보였다. 특히 그람 음성 세균은 충북 음성 고추 재배지 (4번 토양)과 충북 괴산 고추 재배지 (6번) 토양이 현저히 많았고, 형광성 Pseudomonas는 경남 진주의 시설재배지 (7번 토양)에서 현저히 높은 군락을 형성하였고, 이 들 토양은 작물의 생육이 양호한 토양이었다. 따라서 시설재배인 토양에서는 그람 음성 형광성 Pseudomonas 및 mesophillic bacillus의 군집이 토양 환경 및 작물 생육과 미생물의 지표로서 가능성을 제시하였다. 13개 토양에서 분리한 579 균주 중 호기성 세균은 Agrobacterium 102 isolates, Bacillus 112 isolates, Pseudomonas 32 isolates, Kocuria 44 isolates, Paenibacillus 34 isolates 등의 다양한 군집을 이루고 있었고, 또한 624균주의 그람 음성 세균은 Pseudomonas 속이 51%로 제일 많은 군집을 이루고 있었는데 이 들 속내에는 Pseudomonas putica, Pseudomonas fluorescens 등이 많았고 그 다음으로는 Senotrophomonas maltophilia, Bukhodenis cepacia 순으로 다양한 군집을 이루고 있었다. RAPD 분석에 의한 Pseudomonas의 종 다양성은 토양에 따라서 4-31개의 균주 types을 보였으며 특히 4, 6번 토양에서 균주의 다양성이 높게 나타났다. 특히 형광성 Pseudomonas의 군집을 많이 이루었던 7번 토양에서는 26균주에서 5개 균주 types을 보여 종 다양성이 단수하였다. 토양 환경별 미생물 군집은 논 토양에서 신규 세균으로 추정되는 다수의 새로운 분리균이 출현되어 새로운 지표 미생물의 가능성을 제시 하였으며, 또한 MIDI 분석에서 no match 되는 분리균에 대한 미생물 자원의 이용성이 높이 평가되었다.

• Journal of Applied Biological Chemistry
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• 제54권2호
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• pp.135-142
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• 2011

우모분으로부터 높은 함량의 아미노산을 생성하는 Elizabethkingia meningoseptica CS2-1 (729.7 ${\mu}mol/mL$)를 선발하였다. 선발 균주의 protease 활성과 우모 분해능을 위한 최적배지 및 배양조건을 확립하고 우모 분해산물 아미노산의 특성을 조사하였다. E. meningoseptica CS2-1의 최적 배양조건은 $25^{\circ}C$, pH 7.5, 180 rpm이었으며, 효소는 pH 8.0, $40^{\circ}C$에서 가장 높은 활성을 나타내었다. E. meningoseptica CS2-1의 아미노산 생산을 위한 최적 배지조건은 $NH_4Cl$ 0.05%, NaCl 0.05%, $K_2HPO_4$ 0.03%, $KH_2PO_4$ 0.03%, $MgCl_2{\cdot}6H_2O$ 0.01%, urea 0.1%, 닭 우모분 2%이었다. E. meningoseptica CS2-1를 최적 배지 및 배양조건에서 배양한 결과, 아미노산의 총 함량은 1063 ${\mu}mol/mL$로 기본조건 (729.7 ${\mu}mol/mL$)보다 46%로 향상되었고 필수 아미노산 함유량은 315.9 ${\mu}mol/mL$로 기본조건 (219.3 ${\mu}mol/mL$)보다 44%로 향상되었다. 닭 우모분으로부터 추출되 는 17 종류의 아미노산 중 proline (14%), aspartic acid (12%), serine (10%), alanine (10%), glycine (9%), tyrosine (7%)이 주요 아미노산으로 추출되는 특징을 나타내었다. 따라서, E. meningoseptica CS2-1은 닭 우모로부터 아미노산 생산을 위한 미생물유전자원 소재로서 잠재적 가치가 클 것으로 판단된다.

• Journal of Animal Science and Technology
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• 제59권6호
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• pp.15.1-15.5
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• 2017

Background: The horse intestinal tract is sensitive and contains a highly complex microbial population. A shift in the microbial population can lead to various issues such as inflammation and colic. The use of nutraceuticals in the equine industry is on the rise and curcumin is thought to possess antimicrobial properties that may help to minimize the proliferation of opportunistic bacteria. Methods: Four cecally-cannulated horses were utilized to determine the optimal dose of liposomal-curcumin (LIPC) on reducing Streptococcus bovis/equinus complex (SBEC), Escherichia coli K-12, Escherichia coli general, Clostridium difficile, and Clostridium perfringens in the equine hindgut without adversely affecting cecal characteristics. In the first study cecal fluid was collected from each horse and composited for an in vitro, 24 h batch culture to examine LIPC at four different dosages (15, 20, 25, and 30 g) in a completely randomized design. A subsequent in vivo $4{\times}4$ Latin square design study was conducted to evaluate no LIPC (control, CON) or LIPC dosed at 15, 25, and 35 g per day (dosages determined from in vitro results) for 9 days on the efficacy of LIPC on selected bacterial strains, pH, and volatile fatty acids. Each period was 14 days with 9 d for acclimation and 5 d withdrawal period. Results: In the in vitro study dosage had no effect ($P{\geq}0.42$) on Clostridium strains, but as the dose increased SBEC concentrations increased (P = 0.001). Concentrations of the E. coli strain varied with dose. In vivo, LIPC's antimicrobial properties, at 15 g, significantly decreased (P = 0.02) SBEC when compared to 25 and 35 g dosages. C. perfringens decreased linearly (P = 0.03) as LIPC dose increased. Butyrate decreased linearly (P = 0.01) as LIPC dose increased. Conclusion: Further studies should be conducted with a longer dosing period to examine the antimicrobial properties of curcumin without adversely affecting cecal characteristics.