• 한국식품영양학회지
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• 제10권3호
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• pp.350-359
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• 1997

백김치를 담근 후 15$^{\circ}C$에서 60일간 밀폐상태로 발효시키면서 발효일수 경과에 따른 pH, 총산함량 및 미생물수의 변화를 조사하고, 주요 미생물군집을 분리.동정하였다. 담금 즉시의 김치는 pH 6.15, 총산 0.03%였고, Gram 음성 간균류가 치우점 미생물이었으며 이들의 주요 속 구성은 Pseudomonas 55%, Enterobacter 40%, Erwinia 5%였다. 젖산균은 발효 2일 이후부터 최우점 미생물이 되었으며, 발효 4일, 12일 및 50일에 젖산균의 1차, 2차 및 3차 정상기를 각각 나타내었다. 젖산균 2차 정상기의 김치는 pH 3.51, 총산 0.59%로 적숙상태에 해당되며, 이 때 주요 젖산균의 종 구성은 Lactobacillus bavaricus 55%, Leuconostoc mesenteroides subsp. mesenteroides 42.5%, Leuconostoc paramesenteroides 2.5%였다. 젖산균 3차 정상기의 김치는 pH 3.40, 총산 1.10%로 과숙상태에 해당되며, 이 때 주요 젖산균의 종 구성은 Lactobacillus plantarum 65%, Lactobacillus brevis 35%였다. 젖산균들을 동정할 때에 Leuconostoc mesenteroides subsp. mesenteroides, Leuconostoc paramesenteroides, Lactobacillus plantarum 및 Lactobacillus brevis로 동정된 균주들은 기존의 분류체제에 비교적 잘 일치하였으나, Lactobacillus bavaricus로 동정된 균주들은 일치하지 않는 점들을 많이 나타내었다. 젖산균의 수가 증가할 때에 효모의 수가 감소하였고, 젖산균의 수가 감소할 때에 효모의 수가 증가하였다. 효모의 정상기는 젖산균이 제2정상기와 제3정상기의 사이인 30일에 나타났으며, 이 때 주요 효모의 속은 모두 Saccharomyces였다.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 춘계학술발표대회
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• pp.554-557
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• 2000

Strain JV3 was isolated from commercial Swiss cheese products and identified as a bacteriocin producer, which has bactericidal activity against Leuconostoc mesenteroides KCCM 11324. Strain JW3 was identified tentatively as Lactococcus lactis by the API test. The activity of lacticin JW3, named tentatively as the bacteriocin produced by Lactococcus lactis JW3, was detected during the mid-log growth phase, and reached a maximum during the early stationary phase, and decreased after the late stationary phase. Its antimicrobial activity on sensitive indicator cells was completely disappeared by protease IV. The inhibitory activities of lacticin JW3 were detected during treatments of up to $121\'^{circ}C$ for 15 min. Lacticin JW3 was very stable over a pH range of 2.0 to 9.0 The apparent molecular mass of lacticin JW3 was estimated to be in the region of 3-3.5kDa, which was determined by the direct detection of bactericidal activity after SDS-PAGE.

• KSBB Journal
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• 제23권5호
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• pp.449-451
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• 2008

Saccharomyces cerevisiae를 배양하여 ceramide를 생산하였다. 각기 다른 growth phase에서의 ceramide 생산량을 비교 실험하였다. Ceramide는 ELSD가 장착된 HPLC를 통하여 분석하였으며 stationary phase에 접어든 후 12시간 후에 회수, 추출된 양(2.01 mg ceramide/g cell)이 최대인 것으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제13권5호
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• pp.687-691
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• 2003

Whole-cell immobilization of the hydrocarbon rich microalgae, Botryococcus braunii and B. protuberans, in alginate beads under air-lift batch cultures resulted in a significant increase in chlorophyll, carotenoid, dry weight, and 1ipid contents at stationary and resting growth phases, as compared to free cells. Photosynthetic activity in both the species, of Botryococcus was enhanced, relative to free cells, at any growth phase of cultures. Immobilization exerted a protective influence on ageing of the cultures as reflected by higher chlorophyll and dry weight contents. Entrapment also stabilized the chlorophyll and carotenoid contents even at stationary and resting phases as compared to free cells in both the species.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.278.3-279
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• 2003

A chiral stationary phase (CSP) prepared by bonding (18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TA) to aminopropyl silica gel by HPLC was used in resolving several racemic drugs containing primary amino moiety. Most compounds used in this study were resolved on the CSP using 80％ methanol in water (V/V) containing 10mM sulfuric acid as a mobile phase. These results on the CSP were compared to those on the similar CSP derived from 18-C-6-TA of the same chiral selector by different connecting method.

• Journal of Microbiology and Biotechnology
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• 제9권6호
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• pp.732-736
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• 1999

The superoxide dismutase (SOD) in Lactococcus lactis was measured quantitatively and qualitatively under various culture conditions. The L. lactis SOD was induced by oxidative stress. As the concentration of paraquat to produce superoxide radicals increased, the growth of L. lactis decreased with concomitant increase of SOD activity. The SOD activity was found to be growth-phase dependent: when aerobically grown cells entered to the stationary phase, the activity increased gradually until the late stationary phase. From inhibition studies, L. lactis SOD was found to be insensitive to KCN and $H_2O_2$ which are known to inhibit Cu/ZnSOD and FeSOD, respectively. Moreover, as the concentration of manganese in the medium increased, the activity of SOD also increased. These data strongly suggested that L. lactis possessed a single manganese-containing SOD (MnSOD). Finally, a putative sod gene fragment of 510 bp was identified in L. lactis using a polymerase chain reaction (PCR) with degenerate primers designed from the deduced DNA sequences of known SOD genes.

• 약학회지
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• 제32권2호
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• pp.112-116
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• 1988

The resolution of N-trifluoroacetyl (N-TFA) ter-isopropylesters of Ala, Ile, Leu, Val and Phe by gas chromatography on the (S)-5-isobutyl-$N^3$-phenyl-2-thiohydantoin as stationary phase was investigated. The phase was employed at several column temperatures $(140^{\circ}C{\sim}200^{\circ}C)$ and the separation factors were $1.18{\sim}1.45$ range for five amino acid enantiomers. The possible mechanism of chiral recognition was investigated by NMR technique and the association constant$(K_c)$ was calculated as 201.3(r=0.98) for alanyl derivative.

• Bulletin of the Korean Chemical Society
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• 제17권12호
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• pp.1117-1123
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• 1996

Chiral recognition models for resolving π-basic N-acyl-α-(1-naphthyl)alkylamines and π-acidic N-(3,5-dinitrobenzoyl)-α-amino alkyl esters on a (S)-tyrosine-derived chiral stationary phase (CSP) containing both π-basic and π-acidic interaction site have been proposed. In the models, the CSP was supposed to interact with the analytes through the π-π interaction between the 3,5-dinitrophenyl or the 3,5-dimethylphenyl group of the CSP and the 1-naphthyl or the 3,5-dinitrophenyl group of the analyte, and through the hydrogen bonding interaction between the appropriate N-H hydrogen of the CSP and the appropriate carbonyl oxygen of the analyte. In this instance, the alkyl substituent of the pertinent enantiomer of the analyte was found to intercalate between the adjacent strands of the bonded phase and consequently control the trends of the separation factors.

• Bulletin of the Korean Chemical Society
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• 제16권4호
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• pp.344-348
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• 1995

As an effort to elucidate the chiral recognition mechanisms exerted by the (S)-naproxen-derived CSP bearing both π-acidic and π-basic sites, a homologues series of π-basic N-acyl-α-(1-naphthyl)alkylamines and π-acidic N-(3,5-dinitrobenzoyl)-α-amino esters were prepared and resolved. Based on the chromatographic resolution trends of the homologues series of analytes on the (S)-naproxen-derived chiral stationary phase, we proposed chiral recognition mechanisms which demonstrate that the intercalation of the substituent in the analyte molecule between the strands of bonded phase does significantly influence the enantioselectivity for resolving N-acyl-α-(1-naphthyl)alkylamines but the intercalation process is not involved in resolving N-(3,5-dinitrobenzoyl)-α-amino esters.

• Journal of Microbiology
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• 제39권3호
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• pp.168-176
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• 2001

Five different types of catalases from photosynthetic bacterium Rhodospirillum rubrum S1 grown aerobically in the dark were found in this study, and designated Catl (350 kDa), Cat2 (323 kDa), Cat3 (266 kDa), Cat4 (246 kDa), and Cat5 (238 kDa). Analysis of native PAGE revealed that Cat2, Cat3, and Cat4 were also produced in the cells anaerobically grown in the light. It is notable that only Cat2 was expressed much more strongly in response to the anaerobic condition. Enzyme activity staining demonstrated that Cat3 and Cat4 had bifunctional catalase-peroxidase activities, while Catl, Cat2, and Cat5 were typical monofunctional catalases. S1 cells grown aerobically in the presence of malate as the sole source of carbon exhibited an apparent catalase Km value of 10 mM and a Vmax of about 705 U/mg protein at late stationary growth phase. The catalase activity of Sl cells grown in the anaerobic environment exhibited a much lower Vmax of about 109 U/mg protein at late logarithmic growth phase. The catalytic activity was stable in the broad range of temperatures (30$\^{C}$-60$\^{C}$), and pH (6.0-10.0). R. rubrum S1 was much more resistant to H$_2$O$_2$in the stationary growth phase than in the exponential growth phase regardless of growth conditions. Cells of stationary growth phase treated with 15 mM H$_2$O$_2$for 1 h showed 3-fold higher catalase activities than the untreated cells. In addition, L-glutamate induced an 80-fold increase in total catalase activity of R. rubrum S1 compared with magic acid. Through fraction analyses of S1 cells, Cat2, Cat3, Cat4 and Cat5 were found in both cytoplasm and periplasm, while Catl was localized only in the cytoplasm.