• 한국응용과학기술학회지
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• 제37권6호
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• pp.1635-1645
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• 2020

In this study would like to find extending or increasing the efficacy of the antibiotic substance for the strains with resistance to antibiotics or persister cells by inhibition of the resistance. This study was used different species of 'legal high' plants leaves from Leonotis leonurus, Mitragyna speciosa, and seeds from Ipomoea murucoides with antibiotics which are Amoxicillin, Chloramphenicol, Ciprofloxacin, Kanamycin, Oxacillin, and Vancomycin. Legal highs were extracted with methanol. Minimum inhibitory concentration(MIC) testing for a range of antibiotics with extracts of plant was fulfilled by broth dilution methods. In this essay, it was determined in a microdilution assay utilizing suspended in ISB up to a final concentration of 512㎍/ml in 96 wells microtitre plates, threefold and serial dilutions. After that, the microplates were kept in incubator between 35℃ and 37℃ for overnight. Leonotis leonurus, Mitragyna speciosa, and Ipomoea murucoides of Legal highs (512㎍/ml) investigated small activity to inhibit against pathogens which are susceptible Staphylococcus aureus, resistant Staphylococcus aureus, susceptible Enterococcus faecalis, resistant Escherichia coli.

• Mycobiology
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• 제36권4호
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• pp.249-254
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• 2008

Minimal growth inhibitory concentrations (MICs) of chitosan acetate (M.W. 60 kDa) on heterotrophic bacteria (strains MK1, S, and R) isolated from the soft-rotten tissues of Neungee mushroom (Sarcodon aspratus) were measured. The slimy substance produced by the MK1 strain was responsible for the diseased mushroom’s appearance. The S and R strains were members of the Burkholderia cepacia complex. These strains showed different levels of susceptibility toward chitosan acetate. The MIC of chitosan acetate against the MK1 and S strains was 0.06%. The MIC against the R strain was greater than 0.10%. Survival fractions of the MK1 and S strains at the MIC were $3\;{\times}\;10^{-4}$ and $1.4\;{\times}\;10^{-3}$ after 24 h, and $2\;{\times}\;10^{-4}$ and $7\;{\times}\;10^{-4}$ after 48 h, respectively. Survival fractions of the R strain after 24 and 48 hr at 0.1% chitosan acetate were $1\;{\times}\;10^{-2}$ and $6.9\;{\times}\;10^{-3}$, respectively. Compared to the MK1 and S strains, the low susceptibility of the R stain towards chitosan acetate could be due to the ability of the R strain to utilize chitosan as a carbon source. Thirty-eight percent of Neungee pieces treated in a 0.06% chitosan acetate solution for $2{\sim}3$ second did not show any bacterial growth at 4 days, whereas bacterial growth around untreated mushroom pieces occurred within 2 days. These data suggest that chitosan acetate is highly effective in controlling growth of indigenous microorganisms on Neungee. The scanning electron micrographs of the MK1 strain treated with chitosan revealed a higher degree of disintegrated and distorted cellular structures.

• 한국미생물·생명공학회지
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• 제43권3호
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• pp.187-194
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• 2015

인간의 위장관은 매우 복잡한 장내균총으로 이루어져 있으며, 장내균총은 인간의 생리 기능에 있어 매우 중요한 역할을 담당하고 있다. 특히 유아기의 장내균총의 불균형은 면역연관 질병을 일으키는 요인이며 치료 목적으로 probiotics가 유용하게 활용되고 있다. Probiotics의 대표 균종은 L. plantarum으로서 영유아기에 병원균보다 가장 먼저 정착해야 면역 질환을 예방할 수 있다. 그러나 아직 Lactobacillus가 장의 우점종으로 정착하기 위한 환경적 요인과 항생물질분비 조절에 대한 이해는 부족한 실정이다.

• 생명과학회지
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• 제29권1호
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• pp.84-89
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• 2019

신규 항세균물질을 탐색하는 사전조사에서 몇몇 분리균주들이 그람양성 세균과 그람음성 세균 모두에 항균활성을 보이며, 심지어 methicillin내성 Staphylococcus aureus (MRSA)에도 항균활성을 나타내었다. 이들 균주 중에서 한 균주가 표현형과 계통분석을 이용하여 특히 16S 리보좀 RNA 유전자 염기서열에 기초하여 Pseudomonas aeruginosa로 동정되었다. BCNU 1204 균주의 항균물질은 King's medium B (pH 7.0)에서 $35^{\circ}C$의 온도 조건으로 4일 배양 후 가장 최대로 생산되었다. 항균물질을 각종 유기용매로 분획한 결과, P. aeruginosa BCNU 1204의 dichloromethane (DCM)분획과 ethylacetate (EA) 분획이 그람 양성 세균에 강력한 항균활성을 보였으며, 특히 ethylacetate (EA) 분획이 methicillin내성 Staphylococcus aureus (MRSA)에 대하여 강한 항균활성을 나타내었다. Recycling preparative LC와 preparative TLC 로 활성물질 하나(분획 5-2)를 분리하여 GC-MS 분석한 결과 phenazine 화합물에 속하는 phenazine-1-carboxylic acid 로 동정하였다. 그리고 MRSA 균주에 대한 최소저해농도(minimum inhibitory concentration, MIC)가 MRSA균주인 CCARM 3089, 3090, 3091 그리고 3095 균주에 대하여 각각 $25{\mu}g/ml$, $50{\mu}g/ml$, ${\geq}25{\mu}g/ml$ 그리고 ${\geq}50{\mu}g/ml$ 임을 확인하였다. 그러므로 P. aeruginosa BCNU 1204 분리균주는 항 MRSA 항생물질을 개발하기 위한 잠재 가치가 높은 생물자원으로 기대되며, P. aeruginosa BCNU 1204 균주로부터 리더 화합물을 획득하기 위한 보다 많은 연구가 요구된다.

• 한국식품위생안전성학회지
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• 제22권4호
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• pp.317-322
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• 2007

본 연구는 고흡습성 필름에 고추냉이 추출물을 첨가하여 제작한 항균흡습필름의 고등어 중 존재하는 식품위해 미생물에 대한 살균효과를 확인하고자 하였다. 총호기성균 및 식품위해미생물인, Escherichia coli O157:H7, Listeria monocytogenes Vibrio parahaemolyticus를 점 접종하여 항균흡습필름으로 포장한 후 저장온도, 기간별 및 항균 필름의 코팅 횟수가 균의 성장 및 사멸에 미치는 영향을 관찰하였다. $5^{\circ}C$에서 총균수, Escherichia coli O157:H7, Listeria monocytogenes의 성장 억제 효과는 $10^{\circ}C,\;15^{\circ}C$에서 보다 우수하였다. 특히 Usrio Vibrio parahaemolyticus는 $5^{\circ}C$에서 저온에 민감한 반응을 보이면서 모든 시료에서 1일, 4일 후 각각 약 $1\;log_{10}cfu/g\;and\;1.80\;log_{10}cfu/g$ 정도 감소하다가 7일 후에는 검출한계 아래로 모두 사멸하였다. 고추냉이 추출 물질이 함유된 흡습필름은 $10^{\circ}C,\;15^{\circ}C$에서 보다 $5^{\circ}C$ 에서 우수한 항균효과를 보였다. 세 가지 농도별 항균효과는 $5^{\circ}C$ 에서 두드러진 농도별 항균효과 차이를 보였으며 코팅 횟수가 늘어날수록 항균효과가 컸다. 이는 항균필름, 한 가지로만은 저장기간 향상에 한계가 있고 냉장저장이라는 hurdle을 동시에 적용하여 항미생물 synergy 효과를 보인다는 증거가 된다.

• 대한미생물학회지
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• 제35권3호
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• pp.225-237
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• 2000

Vibrio vulnificus, a halophilic vibrio is an estuarine gram-negative bacteria that is associated with severe and frequently fatal wound infections and life-threatening septicemia. Bacteriocins are defined as antibacterial substance produced by various species of bacteria which are usually active against closely related organisms. Bacteriocins have found widespread application in epidemiological studies as specific markers of bacteria. It was proposed by Ha et al. (1990. J. Korean. Soc. Microbiol. 25: 586.) to give the bacteriocins produced by V. vulnificus the name "vulnificins". In the present study, a total of 72 strains of V. vulnificus isolated from patients and oysters were subjected to screen potential producers and indicators of vulnificin, applying ultraviolet induction method. Sensitivity of several strains of Serratia marcesans, Pseudomonas aeruginosa, Shigella flexneri, Salmonella typhi and Yersinia enterocolitica to vulnificins were also examined out. All the tested strains of V. vulnificus produced vulnificins active against indicator strains with various different inhibitory patterns. The spectrum of vulnificin activity and sensitive spectrum of indicator strains were considerably broad. Interestingly, almost all strains of S. marcescens, P. aeruginosa, Salmonella sp., Shigella sp. and Y. enterocolitica tested were sensitive to 1-7 vulnificin(s). Taken together, the present study demonstrated that all of the isolates of V. vulnificus produced vulnificins and that 8 good vulnificin producers and 10 good indicators were detected. These strains can be employed efficiently for establishing vulnificin typing scheme of V. vulnificus and for the detection of bacteriocinogeny and sensitivity in V. vulnificus. Biological role of vulnificin remains to be further elucidated.

• 한국축산식품학회지
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• 제27권4호
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• pp.509-516
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• 2007

Starters of lactic acid bacteria(LAB) were isolated from the commercial yoghurt products and the four isolates have been studied on their identification and some physiological characteristics. For the purpose of identification, microscopic examination, API test, and 16s rRNA gene sequencing were conducted. Isolate A from a yogurt product of local dairy company A was shown to be Gram-positive rod-shaped bacterium. All strains isolated were turned out to be as Lactobacillus paracasei by using a API 50 CHL kit. In contrast, isolate A was identified as a strain of Lactobacillus helveticus based on the 16S rRNA sequencing data, and L. casei ssp. casei for both B and D and L. paracasei for C. All the isolates survived the simulated gastric juice, pH 2.0 within 3 hours and sharply decreased in viability so that no viable cell was observed after 4.5 hours incubation. In addition, the four isolated strains were almost identical in antibiotic susceptibility to six different kinds of antibiotics including erythromycin ($15\;{\mu}g$), ampicillin ($10\;{\mu}g$), gentamycin ($10\;{\mu}g$), neomycin ($30\;{\mu}g$), but rather resistant to colistin ($10\;{\mu}g$) and streptomycin ($10\;{\mu}g$). It was noteworthy that four isolates were confirmed to produce antibacterial substance against foodborne pathogens of Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli 0157:H7 as test organisms based on the inhibitory zones on an MRS soft agar medium. At presence, the inhibitory factor is unknown so that further studies are required to ascertain the active factor responsible for the inhibitory activities.

• 치위생과학회지
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• 제12권2호
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• pp.155-162
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• 2012

본 연구는 소목(Caesalpinia sappan L.)의 6가지 유기용매 분획물 중 IP-3의 항균활성을 및 부착능을 측정하고 다음과 같은 결과를 얻었다. 1. Methanol에 의해 분리된 소목의 항균 물질 수율은 총 4.8%로 나타났으며, 여러 분획물 가운데 EtOAc 분획물(IP-3)에서 3.94%로 가장 높은 수율을 보였다. 2. 소목의 EtOAc 분획물에서 최종 정제된 활성물질은 UV 288.3 nm에서 최대 흡수피크를 나타내었으며, NMR spectrum을 통해 brazilin(($C_{16}H_{14}O_5$)으로 확인되었다. 3. S. mutans에 대한 소목의 EtOAc 분획물의 항균 활성은 최소억제농도(MIC) 3.1 mg/ml에서 균의 생장을 억제하였다. 4. S. mutans 부착억제효과는 하이드록시아파타이트(HA)를 S. mutans와 24 시간 동안 함께 배양한 대조군은 균 부착률이 높게 관찰되었으나, 소목의 EtOAc 분획물을 처리한 군에서는 HA에 S. mutans의 부착이 매우 적게 나타났다. 이상의 결과를 통해, 소목에서 추출된 EtOAc 분획에 존재하는 brazilin이 구강 내 우식원성세균에 강한 항균력을 가지고 있는 것으로 판단되며, 특히 S. mutans의 부착 억제능이 확인되어 우식원성 균주에 대한 생약치료제로 활용이 가능할 것으로 사료된다.

• 대한화장품학회지
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• 제47권3호
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• pp.247-254
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• 2021

여드름은 털피지샘단위(pilosebaceous unit)와 관련된 만성 염증 피부 질환으로, 여드름 병변에서는 피지 과다분비(hyperseborrhea)나 이상분비(dysseborrhea), 염증반응, 그리고 다른 피부상재균들에 비해 증가된 Cutibacterium acnes (C. acnes)로 인한 피부 미생물 균총의 불균형이 관찰된다. 이 연구는 개똥쑥 추출물(Artemisia annua extract: AAE)의 항여드름 효과를 확인한 것으로, 피부 미생물 균총의 균형유지와 관련된 항균효과와 염증반응의 억제, 과도한 피지 분비의 감소 측면에서 실험을 진행하였다. C. acnes와 Staphylococcus epidermidis(S. epidermidis)를 AAE와 공동배양 하였을 때, S. epidermidis의 성장률은 저해되지 않았지만 C. acnes의 성장률은 저해된 것을 확인하였다. 또한 AAE를 처리하여 배양한 C. acnes 배양배지를 세포에 처리하였을 때, 인터루킨-1β(IL-1β), 종양괴사인자-α(TNF-α)와 인터루킨-6(IL-6) 같은 사이토카인 분비의 감소와 TLR2 활성 억제도 확인하였다. 마지막으로 피지세포에 AAE를 처리한 결과, 팔미트산에 의해 유도된 피지형성을 감소시키는 것을 확인하였다. 이 결과들은 AAE가 다양한 타깃을 지닌 천연추출물로써 여드름의 주요 원인들인 C. acnes의 선택적 성장저해와 C. acnes로부터 유도되는 염증반응을 억제할 수 있으며, 과도한 피지형성을 감소시켜 결과적으로 여드름을 완화시키는 물질로 사용될 수 있다는 것을 제시한다.

• 대한미생물학회지
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• 제11권1호
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• pp.27-32
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• 1976

Sodium amylosulfate(SAS) has been reported to be an effective substance to inactivate the anti-bacterial activity of blood in blood culture media. The advantage of the use of SAS over sodium polyanethol sulfonate(SPS) is that it does not inhibit the growth of some bacteria! species which are known to be inhibited by SPS. As to S. typhi, SPS is reported to enhance the growth, however the effect of SAS on this organism is not known as yet. Using 43 strains of S. typhi, isolated from clinical materials, the authors tried to determine the effect of SAS on this organism. The methods used for this study were : the SPS and SAS paper disk I sensitivity test, tests on the growth in trypticase soy broth(TSB) with SPS and with SAS, and experimental blood culture in SPS and SAS incorporated TSB. The following results were obtined. 1). S. typhi strains with the turbidity of No. 0.5 tube of MacFarland nepherometer were inoculated onto Mueller-Hinton plate and 1mg disk of SPS and SAS were applied. After 24-hour incubation, none of the 43 strains showed inhibition zone by SPS disk, but all of them showed zones by SAS disk with a mean zone diameter of 9.5mm(Table 1). 2) Inocula consisting of one to 54 viable counts of 37 strains were inoculated into three different media; TSB with 0.05% SPS, TSB with 0.05% SAS and TSB alone. After 24-hour incubation the mean of the optical densities of each medium were 0.483, 0.482 and 0.459 respectively, showing that SAS does not inhibit the growth of S. typhi. Moreover it was shown that there was no correlation between the amount of inocula and growth(Table 2 and Fig. 1). 3). Each set of media in 5 ml amounts consisting of one tube of TSB with 0.05% SPS, one tube of TSB with 0.05% SAS and two tubes of TSB were inoculated with 8, 64. 640 and 6400 viable counts of bacteria. Then 0.5 ml of fresh normal blood was added to all tubes except for one tube of TSB. Macroscopic observation after 24 hour incubation showed a heavy growth in all tubes except for the tube of TSB plus blood, which showed only a light growth in the tube of the heaviest inoculum. This result clearly demonstrates that the growth of S. typhi is inhibited by some antibacterial activities of fresh blood, which are counter acted by SPS and SAS(Table 3). Between SPS and SAS, there was no significant difference found(Table 4 and Fig. 2). With all these results it can be postulated that the addition of SAS into a rountine blood culture media may raise the positivity of S. typhi isolation and shorten the incubation period.