• 제목/요약/키워드: Microbiological Change

검색결과 239건 처리시간 0.019초

조림간장의 표준화와 조리특성 (Standardization and Cooking Properties of Spiced Soy Sauce)

  • 박승애;신미혜
    • 한국식품조리과학회지
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    • 제14권1호
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    • pp.97-105
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    • 1998
  • This study was carried out in order to standardize the processing method of spiced soy sauce, to get the sensory scores for organoleptic properties in different cooking of each food items, and to analyze the microbiological and chemical properties during storage periods. In determining the optimum conditions for standardizing of spiced soy sauce, the best sensory score was found in the ratio of soy sauce to sugar of 1:0.7. In the result of microbial experiment on standardized spiced soy sauce, the stability of storage at 40$^{\circ}C$ up to 6 weeks was proved. The standardized spiced soy sauce which was composed of about 45.5% water, 6% crude protein, 11.7% reducing sugar and 32.1% invert sugar has not shown any significant difference during storage for 6 weeks at 40$^{\circ}C$ compared with the state immediately after processing. In the test of saltiness, specific gravity, viscosity and Hunter's color value, there was no notable change during storage at 40$^{\circ}C$. In the experiment of free amino acid and total amino acid, main amino acids were glutamic acid and aspartic acid, which were not significantly changed during storage compared with processing state. In the analysis of mineral contents, sodium accounts for 95% of the total minerals, followed by phosphorus, magnesium, etc., in order, and there was no change during storage.

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김치의 저온 발효 중 미생물 변화 양상 (Change of Microbial Communities in Kimchi Fermentation at Low Temperature)

  • 박정아;허건영;이정숙;오윤정;김보연;민태익;김치경;안종석
    • 미생물학회지
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    • 제39권1호
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    • pp.45-50
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    • 2003
  • 분자 생물학적 방법 인 DGGE를 이용하여 저온에서 김치가 발효되는 동안 관여하는 미생물의 다양성과 변화양상을 분석하였다. 김치를 저온 ($4^{\circ}C$)에서 발효시키는 60 일 동안 5 일 마다 시료를 채취하였으며, 채취한 김치 시료에서 genomic DNA를 추출하여 실험을 수행하였다. 김치 시료 genomic DNA로부터 16S rDNA의 V3영역을 증폭하여 DGGE를 수행한 결과에서 관찰된 amplicon들의 염기서열을 분석한 결과 저온에서 김치가 발효되는 동안 젖산균들이 주요 미생물 군집으로 나타났으며, 그 중에서도 Weissella koreensis가 발효 전 과정 동안, Lactobacillus sakei의 경우는 발효 10 일째부터, 그리고 Leuconostoc gelidurn은 발효30 일째부터 amplicon들의 농도가 진하게 나타나 이들이 저온에서 김치 발효 과정 동안의 우점종 균주들 임을 알 수 있었다.

Rhodospirillum rubrum Plasmid pKY1의 유전정보 분석과 그의 활용에 관한 연구 (Genetic Analysis and its Application of Rhodosprillum rubrum PKY1 Plasmid)

  • 김복환;김정목
    • 미생물학회지
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    • 제40권2호
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    • pp.172-177
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    • 2004
  • 광합성 박테리아 Rhodospirillum rubrum은 광원의 조건에 따라 균주 내의 신진대사 양상이 변화된다고 보고 되어 왔다. 이러한 광조건에 의한 신진대사 변환 과정을 담당하는 유전자에 대한 연구는 광합성 박테리아에 관한 주된 과제 중 하나이다. 근래 이러한 광조건에 의한 균주내 변화 과정이 균주가 지니는 extrachromosomal plasmid와 관련이 있음이 보고되었다. 본 연구는 광합성 박테리아 R. rubrum의 extrachromosomal plamid pKYl 을 분리 정제하고 이를 제한효소 HindIII로 단편화 하여 이들 단편의 일부에 대한 염기서열을 분석하고 이들의 기능을 추론하였다. 본 연구를 통하여 plasmid pKY1에 박테리아의 유전적 재조합 (genetic recombination)에 관여하는 단백질에 대한 정보가 위치하고 있음을 유전자 및 아미노산 상동성 조사를 통하여 알 수 있었다.

백김치 유래 유산균을 이용한 요구르트의 Anti-Helicobacter pylori 활성 (Anti-Helicobacter pylori Activity of Yogurt Fermented with Lactic Acid Bacteria from Baikkimchi)

  • 임성미;김덕술;안동현
    • 미생물학회지
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    • 제50권4호
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    • pp.334-344
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    • 2014
  • 백김치로부터 분리된 유산균으로 제조된 요구르트를 냉장 보관하는 동안 미생물학적 및 물리화학적 특성 및 Helicobacter pylori ATCC 43504에 대한 항균 활성을 조사하였다. 요구르트의 유산균수, 적정산도, 점도 및 총 고형물 함량은 사용된 균주에 따라 유의적인 차이가 있었으나, 발효 직후부터 7일간 저장하는 동안 유의할만한 차이 없이 일정하게 유지되었다. Lactobacillus brevis BK11과 Lactobacillus paracasei BK57 균주로 발효시킨 요구르트는 인공 위액과 담즙액에 대해 다른 균주들 보다 강한 저항성을 보였다. 한편, 이들 유산균으로 제조한 요구르트 내에 존재하는 유산 생성량은 상대적으로 높았으므로 H. pylori와 혼합 배양한 결과 대조구에 비해 유의적인 항균 효과를 나타낸 것으로 추정되었다. 특히, L. brevis BK11에 의해 발효시킨 요구르트에 의해선 AGS 세포에 대한 H. pylori의 부착을 억제할 수 있었고, 이들이 생산하는 urease의 활성을 낮추는데도 효과적이라는 것을 확인하였다.

Lichen Flora around the Korean Antarctic Scientific Station, King George Island, Antarctic

  • Kim, Ji-Hee;Ahn, In-Young;Hong, Soon-Gyu;Andreev, Mikhail;Lim, Kwang-Mi;Oh, Mi-Jin;Koh, Young-Jin;Hur, Jae-Seoun
    • Journal of Microbiology
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    • 제44권5호
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    • pp.480-491
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    • 2006
  • As part of the long-term monitoring projects on Antarctic terrestrial vegetation in relation to global climate change, a lichen floristical survey was conducted around the Korean Antarctic Station (King Sejong Station), which is located on Barton Peninsula, King George Island, in January and February of 2006. Two hundred and twenty-five lichen specimens were collected and sixty-two lichen species in 38 genera were identified by morphological characteristics, chemical constituents, TLC analysis and ITS nucleotide sequence analysis.

Identification of Essential Amino acid Residues in Valine Dehydrogenase from Streptomyces albus

  • Hyun Chang-Gu;Kim Sang-Suk;Suh Joo-Won
    • Journal of Microbiology
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    • 제44권1호
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    • pp.50-53
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    • 2006
  • Cys-29 and Cys-251 of Streptomyces albus valine dehydrogenase(ValDH) were highly conserved in the corresponding region of $NAD(P)^+$-dependent amino acid dehydroganase sequences. To ascertain the functional role of these cysteine residues in S. albus ValDH, site-directed mutagenesis was performed to change each of the two residues to serine. Kinetic analyses of the enzymes mutated at Cys-29 and Cys-251 revealed that these residues are involved in catalysis. We also constructed mutant ValDH by substituting valine for leucine at 305 by site-directed mutagenesis. This residue was chosen, because it has been proposed to be important for substrate discrimination by phenylalanine dehydrogenase (PheDH) and leucine dehydrogenase (LeuDH). Kinetic analysis of the V305L mutant enzyme revealed that it is involved in the substrate binding site. However it displayed less activity than the wild type enzyme toward all aliphatic and aromatic amino acids tested.

Aspergillus tubingensis의 acid protease에 관한 연구 I (Studies on acid protease produced from Aspergillus tubingensis I)

  • 정윤수;조영;한석현
    • 미생물학회지
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    • 제20권3호
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    • pp.105-112
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    • 1982
  • The strain of Aspergillus, 6368A, producing acid protease showing high activity was isolated from soil, as a result of wide research about mold group. This strain was identified as a species of Aspergillus tubingensis by the investigation of morphological characteristics. The change of the enzyme production under the various media and culture condition was also studied. The optimum pH and stability of crude acid protease are 2.5, 2.0~4.5 and the optimum temeprature and thermal inactivation waas shown $50^{\circ}C,\;55^{\circ}C$, respectively. From the result of the study on the effects of metal ions, it was found that $MnCl_2,\;CoCl_2,\;CuCl_2,\;SrCl_2,\;and\;NiCl_2$ slightly increased the enzyme activity, on the other hand $ZnCl_2,\;CaCl_2,\;MgCl_2,\;SLS,\;and\;KMnO_4$ decreased it.

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L-Glutamic Acid 생성균에 관한 연구 1 (Studies on L-Glutamic Acid-Producing Bacteria(I))

  • 홍순우;하영칠;차승희
    • 미생물학회지
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    • 제12권1호
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    • pp.37-51
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    • 1974
  • Three strains which accumulated large quantities of L-hlutamic acid as the chief product of metabolism in the presence of glucose and inorhanic ammonium salt under the aerobic condition sere newly isolated. These strains have the general characters as follows: Gram-positive, short fod-shaped, non-sporulating, non-motile, and facultative anaerobe. A change of cell shates was not almost observed in their life cycles and neither a phenomenon of cell-elongation nor a pleomorphism was recognized in any cases. Together with rigid stability in Gram-stain, these characters as above indicated evidences that newly isolates would belong to genus Brevibacterium clearly differentiated from genus Corynebacterium. At the same time the newly isolates, in addition to nutritional requirement of biotin and thiamine, showed the distinctive character of requirement of special amino acid such as histidine or cysteine for their considerable growth. These physiological characters including nitrates reduction, reaction on milk, and slow formation of acid from sugar also were useful in confirming that these bacteria would be Brevibacterium ammoniagenes.

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펌제와 염모제가 곱슬모에 미치는 영향에 관한 연구 (The study on Effects of Curly Hair by the Permnent wave and Dye)

  • 이하나;강상모
    • 한국패션뷰티학회지
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    • 제6권2호
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    • pp.73-79
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    • 2008
  • To study of the rate of damage and morphological change when apply perm and dye according to kinds of curly hair, measured the thickness of hair and divided the samples into groups. Measured the chromaticity and thickness according to kinds of curly hair and chemical treatment with Spectrum colormeter and Micrometer. Measured the tensile strength of hair then calculated the damage rate. After tensile test, took photographs of the section and surface with the electron microscope.

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S. peucetius subsp. caesius와 S. platensis의 원형질체 융합 및 융합균주의 분리 (The Interspecific Protoplast Fusion between S. peucetius subsp. caesius and S. platensis)

  • 임미송;이강만
    • 약학회지
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    • 제38권6호
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    • pp.696-702
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    • 1994
  • An interspecific fusant strain, MS1, was obtained by protoplast fusion between S. peucetius subsp. caesius and S. platensis. We studied on the microbiological and cultural characteristics of the fusant MS1. In liquid culture, the viscosity of culture broth of S. peucetius increased during incubation However the fusant MS1 formed pellet like S. platensis without viscosity change. On agar medium the colony morphology of MSI resembled S. platensis but the color was similar to S. peucetius. The fermentation products of the fusant MS1 was identical with S. peucetius.

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