• Food Science and Biotechnology
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• 제17권3호
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• pp.679-682
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• 2008

A lactic acid bacterium producing an antimicrobial substance against Escherichia coli O157:H7 was isolated from raw milk and identified as Lactobacillus amylovorus ME-1. In addition to E. coli O157 :H7, the antimicrobial substance also inhibited the growth of Bacillus cereus, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, Staphylococcus aureus, Streptococcus agalactiae, Streptococcus pyrogenes, and Yersinia enterocolitica. The antimicrobial substance was stable at pH 2-12 and $121^{\circ}C$ for 15 min and insensitive to proteinase K, protease, amylase, and catalase. Purification of the antimicrobial substance was conducted through methanol and acetonitrile/ethylacetate extraction, ultrafiltration with a 500 Da cutoff, thin layer chromatography (TLC) with silicagel 60, and high performance liquid chromatography (HPLC) with a $C_{18}$ reverse phase column. The ${\lambda}_{max}$ of the purified antimicrobial substance was determined as 192 nm by ultra violet (UV) scanning, while the molecular weight was estimated as 453 Da based on the mass spectrum. Accordingly, the current results suggest that the antimicrobial substance from the L. amylovorus ME-1 was not a bacteriocin, but rather a new non-proteinaceous substance distinct from acidophilin, acidolin, diacetyl, and reuterin.

• Applied Microscopy
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• 제28권3호
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• pp.329-343
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• 1998

Early wound healing responses in the skin of the Korean fire bellied toad, Bombina orientalis, were examined using histochemical , scanning and transmission electron microscopical techniques. Cutaneous wounds were induced by sharp razor blade , and maintained in special cages for up to 3 days. By this treatment whole parts of epithelium and dermis were profoundly affected. After injury, retraction of damaged surface of the skin was observed. At 3 hours after injury, poly-band was form by mucous substance. The wound skin consisted of mucous gland secreted mucous substance which flows into wound cavity and the wound area was sealed by mucous substance which form thick layer at 6 hours. It appeared that natural disposition showed acid and neutral mucous substance by reaction of PAS and Alcian blue (pH 2.5) staining. After formation of the poly-band, epithelial cells were formed by migration of regenerating epithelial cells. These cells moved over the wound surface by migration at 12 hours after wounding. Poly-band was much increased in thickness and migrating cells were completely formed wound closure at 24 hours post-wounding. After 72 hours regenerated epithelial layer consists of four or five cell layers which are similar to clear, granular, and spinous layer.

• 한국미생물·생명공학회지
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• 제1권2호
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• pp.89-92
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• 1973

항효모성물질인 Astradix-P의 항균력은 염기성 아미노산이 존재할 때 길항적으로 감소하였다. 금번에는 염기성물질 및 vitamin이 항생력에 어떠한 영향을 미치는가 조사한 결사 adenine 및 thiamine, riboflavin, pyridoxin cobalamin, nicotinic acid, folic acid, p-aminobenzoic acid, pantothenic acid, biotin, inositol등에 의해서는 전혀 영향을 받지 않았다

• 한국식품영양과학회지
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• 제23권1호
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• pp.104-109
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• 1994

For Selection of powerful antagonistic bacteria for biological control of soil borne Erwinia rhapontici causing rot of the vegetables and fruit, excellent straints (S43, S62) were selected from rhizopere in vegetables root rot suppressive soil. Selected strains were identified to be Pseudomonas sp. with Apl 20NE kit tests. Optimum culture condition for the maximum production of antagonistic substance was determined , when isolate was cultured in 523 synthetic broth media at pH 7.0 and 30 during 3 days. Antagonistic substance productivity of isolated Pseudomonas sp. (S43, S62) in the fertilizer soil were increased to about 40-50% compared to that in the non fertilizer soil.

• 한국미생물·생명공학회지
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• 제14권2호
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• pp.145-153
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• 1986

본 연구에서는 토양으로부터 분리한 Aspergillus 속의 한 균주가 Colubridae과 독사의 사독 주성분인 출혈독을 강하게 불찰성화 시키는 물질을 생성하므로 이 물질을 분리한 후 부분적으로 정제하여 결정이 형성됨을 확인하였다. 본 물질은 Colubridae과의 Agkistrodon bromohoffi brevicaudus, A. saxatilis, Trimersurus flavoviridis, A. acutus 사독의 출혈독을 정량적으로 불활성화 시키며, 최대 저해률은 80-90%에 이르며 실험한 대상 동물에 따라 활성차이가 다소 있음이 인정되었다. 예로서 병아리 피하반응에 있어서는 T. flavoviridis 사독을 동량의 시료로서 처리하였을 때 완전히 출혈활성이 저해되나 mouse 족도 조직내 반응에서는 사독의 8배량의 시료로서 출혈활성이 거의 저해되었다. 또 본 시료는 출혈독이 지니고 있는 치사활성에 있어서도 독량의 약 3배량의 시료에 의해서 거의 치사 활성을 저해하며, T. flavoviridis 사독의 HR-I 및 HR-II부종활성에 대해서는 본 물질의 1/2량 이상의 농도에서는 시료농도에 관계없이 약 50% 정도로 저해하는 반면 A. bromohoffi brevicaudus 전독의 부종은 거의 완전히 저해하였다. 사용 균은 2종의 항출혈성 물질을 생성하고 있음이 가면피내 반응에서 확인되었다.

• Environmental Engineering Research
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• 제15권1호
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• pp.3-7
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• 2010

To better understand the ecology of tetrade forming organisms (TFOs) floating in a large amount of dairy wastewater treatment plant (WWTP) effluent (sequencing batch reactor [SBR]) during the inefficient phosphorus (P) removal process of an enhanced biological P removal system, the TFOs from the effluent of a full scale WWTP were separated and attempts made to culture the TFOs in presence/absence of oxygen. The intact TFOs only grew aerobically in the form of unicellular short-rods. Furthermore, to identify the intact TFOs and unicellular short-rods the DNAs of both were extracted, analyzed using their denaturing gradient gel electrophoresis (DGGE)-profiles and then sequenced. The TFOs and unicellular short-rods exhibited the same banding pattern in their DGGE-profiles, and those sequencing data resulted in their identification as Acinetobacter sp. The intact TFOs appeared in clumps and packages of tetrade cells, and were identified as Acinetobacter sp., which are known as strict aerobes and efficient P-removers. The thick layer of extracellular polymeric substance surrounding Acinetobacter sp. may inhibit phosphate uptake, and the cell morphology of TFOs might subsequently be connected with their survival strategy under the anaerobic regime of the SBR system.

• 생물정신의학
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• 제24권3호
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• pp.134-141
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• 2017

Objectives A retrospective case series study was conducted to investigate the clinical characteristics of psychotic disorders induced by appetite suppressants, phentermine and phendimetrazine. Methods A retrospective electronic medical record review identified 5 admitted patients who had psychotic symptoms after taking phentermine or phendimetrazine. Clinical information was reviewed and summarized in each case. Results Hallucinations were reported in all cases, including auditory, visual, olfactory and somatic hallucinations. After discontinuation of phentermine or phendimetrazine, the symptoms rapidly improved with low dose of antipsychotics. Patients tended to have less prominent negative symptoms and higher insight into illness, and often showed depressive mood. These clinical characteristics were similar to psychosis induced by amphetamines. Two patients developed stimulant use disorder while using phentermine. Conclusions These findings call for awareness of the risks associated with use of appetite suppressants. Prescription of phentermine or phendimetrazine should be accompanied by close monitoring of mental status, and suspicion for substance/medication-induced psychotic disorder.

• Applied Biological Chemistry
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• 제14권1호
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• pp.35-41
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• 1971

신미종(辛味種)고추의 추숙(追熟)에 따른 지질(脂質)의 변화(變化)를 중성지질(中性脂質)과 극성지질(極性脂質)로 분획(分劃)하여 실험(實驗)한 결과(結果)는 다음과 같다. 1. 중성지질(中性脂質)의 함량(含量)은 cli. stage에서 최저치(最低値)가되고 극성지질(極性脂質)의 함량(含量)은 post-cli. stage에서 격감(激減)하고있다. 2. 중성지질(中性脂質)의 지방산(脂肪酸)으로서 주(主)가 되는 것은 linoleic acid이고 이것은 추숙(追熟)에 따라 점감(漸減)하고 있다. 3. 중성지질(中性脂質) fatty acid의 saturates/unsaturates치(値)가 cli. stage에서 최저(最低)가 되는데, 이것을 중성지질함량(中性脂質含量)도 cli.stage에서 최저(最低)를 가리키는 것과 아울러 생각할때 climacteric rise가중성지질(中性脂質)의 대사(代謝)와 관계(關係)가 있는것 같다. 4. 극성지질(極性脂質)의 지방산(脂肪酸) 조성(組成)은 추숙(追熟)에 따라 linoleic acid가 줄곧 감소(減少)하고 linoleic acid가 증가(增加)하여 cli. stage에서 역전(逆轉)하고 있는데, 이것은 고추의 climacteric rise에 따라 일어나는 막성분(膜成分)의 변화(變化)를 가리키는 한 지표(指標)가 될 수 있을 것 같다.

• 한국미생물·생명공학회지
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• 제42권4호
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• pp.393-401
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• 2014

청국장으로부터 Bacillus cereus에 대한 항균활성이 가장 높은 균주를 분리하여 형태학적, 생화학적 특성과 16S rDNA 염기서열 결정을 통해 Bacillus subtilis HH28으로 동정 및 명명하였다. B. subilis HH28의 생육시기에 따른 항균활성을 측정해 본 결과, 생육이 대수증식기인 9시간부터 생성되어 사멸기인 60시간에 가장 높은 활성(80 AU/ml)을 나타내었고 144시간(6일)까지 항균활성을 유지하였다. 항균물질의 정제는 황산암모늄 침전과 DEAE-sepharose fast flow, sephacryl S-200HR를 이용하였고, 19.7배의 정제도와 38.4%의 수율로 정제되었다. Tricine SDS-PAGE와 directed detection을 통해 항균물질의 분자량이 약 3,500 Da임을 알 수 있었다. 또한 본 연구의 항균물질을 B. cereus 뿐만 아니라 Listeria monocytogenes, Vibrio parahaemolyticus의 식중독 균에서도 우수한 항균활성을 나타내었고, 항균작용의 기작은 미생물을 사멸시키는 살균작용이였다. 또한 온도 안정성 실험에서 $40-80^{\circ}C$까지 안정했고, pH 안정성 실험에서는 pH 2-9까지 안정하여 비교적 온도와 pH에 안정하였다. 효소에 대한 영향 실험에서는 단백질 분해효소에 의해 항균활성이 실활되어 본 연구의 항균물질은 단백질성임을 알 수 있었다. 위와 같은 특성으로 보아 B. subtilis HH28이 생산하는 항균물질은 천연 식품 보존제 및 사료 보존제, 항생제 대체 의약품으로 사용할 수 있는 잠재력을 가지고 있으며, 향후 이 항균물질의 정확한 구조 및 특성 규명 등의 연구가 필요하다.

• 상하수도학회지
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• 제22권1호
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• pp.73-78
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• 2008

Water resource can be examined using biological sensors. Algae has been one of the biological sensors used to evaluate and to monitor the water pollution. The monitoring system, however, has not been used to determine what kind of the toxicological substance is in the water. It needs additional expensive chemical test to figure out the cause of the water pollution. In this study, an endeavor is made to identify the toxicant in the water using the shape of the chlorophyll fluorescence induction curve(FIC) from algae using monitoring system. Fundamental curves are obtained from the experiments with specified amount of toxicant. Baysian method is utilized to determine the unknown toxicant in the water by comparing it with the fundamental curves. The results shows that the proposed method works fairly well.