• 한국식품영양학회지
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• 제21권1호
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• pp.15-21
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• 2008

In this study, the minimum inhibition concentration(MIC), growth inhibition activity, and colony forming inhibitory activity of water soluble propolis against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae and Salmonella enteritidis were tested. The MICs of the water soluble propolis against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, and Salmonella enteritidis were 312.5 ppm, below 156.3 ppm, 625 ppm, 10,000 ppm, above 10,000 ppm, 10,000 ppm, above 10,000 ppm, above 10,000 ppm, 10,000 ppm, and above 10,000 ppm, respectively. The growth inhibition concentrations against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, and Klebsiella pneumoniae were 156.3 ppm, below 156.3 ppm, 625 ppm, 5,000 ppm, 10,000 ppm, 10,000 ppm, 10,000 ppm, 10,000 ppm, and 5,000 ppm, respectively. However, 10,000 ppm did not inhibit the growth of Salmonella enteritidis. Finally, the colony forming inhibitory activities against Bacillus cereus, Bacillus subtilis, Listeria monocytogenes, Staphylococcus aureus, Streptococcus mutans, Citrobacter freundii, Enterobacter aerogenes, Escherichia coli, Klebsiella pneumoniae, and Salmonella enteritidis were 98.0%, 99.8%, 69.8%, 98.1%, 62.0%, 63.1%, 79.5%, 61.9%, 79.6%, and 0.0%, respectively.

• 한국식품영양학회지
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• 제19권4호
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• pp.526-531
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• 2006

자몽 종자 추출물의 항균성을 조사하기 위하여 그람 양성균인 Bacillus cereus, Bacillus subtilis, Listeria monocytogenes와 그람 음성균인 Escherichia coli, Salmonella enteritidis, Serratia marcescem를 대상으로 하여 최소 저해 농도, 생육 저해 활성, 콜로니 형성 저해 활성을 실험하였다. 그람 양성균에 대한 자몽 종자 추출물의 최소 저해 농도는 12.5 ppm정도로 상대적으로 낮았으며, 그람음성균의 최소저해 농도는 50ppm 이상으로 상대적으로 높았다. 균주의 증식에 대한 생육 저해 활성을 조사한 결과 Bacillus cereus는 1ppm 이하, Bacillus subtilis는 6.25 ppm, Listeria monocytogenes는 1ppm 이하, Escherichia coli는 6.25 ppm, Salmonella enteritidis는 25 ppm Serratia marcescem는 25pp부터 생육이 저해되었다. 그람 양성균의 콜로니 형성 저해활성은 Bacillus cereus는 93.9%, Bacillus subtilis는 94.0%, Listeria monocytogenes는 99.9%, 그람 음성균의 콜로니 형성 저해 활성은 Escherichia coli는 4.4%, Salmonella enteritidis는 82.7%, Serratia marcesem는 86.4%로, 그람 양성균에 대해서는 높은 저해 활성을 보였으며, 그람 음성균에 대해서는 비교적 낮은 저해 활성을 보였다.

• 대한한방종양학회지
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• 제2권1호
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• pp.75-90
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• 1996

This experiment was designed to study the antitumor effects and Activity of Natural Killer Cell of semen Tiglii plus Rhizoma Rhei. The cytotoxic and antitumor effects were evaluated on human cell lines(A549, Caki-1, LL2, Sarcoma 180, NIH/3T3) after exposure to prebrewed Semen Tiglii plus Rhizoma Rhei water extract 0.1, 0.2, 0.4, 0.8, 1.6mg/ml using in MTT assay, LDH, colony forming efficency and SRB assay which were regarded as a valuable method for cytotoxic and antitumor effects of unknown compound on tumor cell lines. The results obtained in this studies were as follows. 1. From the result of MTT assay, the cytotoxicity of ST(生巴豆霜), ST+RR(生巴豆霜加大黃) were concentration-dependently increased in both group of the ST and ST+RR, the cytotoxicity of ST+RR(生巴豆霜加大黃) was similar to that of ST(生巴豆霜). 2. From the result of LDH, the cytotoxicity of ST, ST +RR were concentrati -on-dependently increased in both group of the ST and ST+RR, the cytotoxicity of ST+RR was similar to that of ST. 3. The antitumor effect on A549 tumor cell from the result of colony forming efficiency showed the inhibitory effect on the growth in both group of the ST and ST+RR, the inhibitory effect on growth was low slightly in the ST+RR. 4. From the result of SRB assay, the antitumor effect on caki-1 tumor cell of ST, ST+RR showed the inhibitory effect on the growth in both group of the ST and ST+RR, the antitumor effect of ST+RR was similar to that of ST. 5. Median survival time and increased life span were increased slightly in both group of the ST and ST+RR. 6. The inhibitory effect on the growth of Sarcoma 180 and Lewis lung carcinoma tumor cell were increased slightly in both group of the ST and ST+RR. 7. The activity of NK cell was increased in the ST+RR.

• 한국식품영양학회지
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• 제14권6호
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• pp.579-584
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• 2001

Chitosna을 Bacillus pumilus BN-262 유래의 chitosanase로 처리하여 trimer, tetramer, pentamer가 전체 올리고당 중 64.3%에 달하는 비교적 저분자의 chitooligosaccharides로 구성된 LMW-chitooligosaccha-rides를 얻었으며, chitosan을 Trichoderma viride 유래의 cellulase로 처리하여 중합도7이상의 것이 전체 올리고당 중 49.3%에 달하는 상대적으로 분자량이 큰 chitooligosaccharides로 구성된 HMW-chitooligosac-charides를 얻었다. 제조된 chitooligosaccharides의 항균성과 콜로니 형성 저해 활성을 측정하였다. LMW chitooligosaccharides의 Bacillus cereus, Bacillus subtilis, Candida albicans, Escherichia coli, Escherichia coli O157:H7, Lactobacillus plantarum, Listeria mo-nocytogenes, Pseudomonas aeruginosa, Salmonella enteritidis, Salmonella typhimurium, Staphylococcus aureus, Streptococcus mutans에 대한 MIC(최소저해농도)는 각각 1.5%, 1.5%, above 2.0%, 1.5%, 1.5%, below 0.5%, 2.0%, 1.5%, above 2.0%. 1.0%, 1.5%, 1.0%였으며, HMW-chitooligosaccharides의 Bacillus cereus, Bacillus subtilis, Candida albicans, Esche-richia coli, Escherichia coli O157 : H7, Lactobacillus plantarum, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella enteritidis, Samlmonella typhimurium, Staphylococcus aureus, Streptococcus mutans에 대한 MIC는 각각 1.0%, 1.0%, 2.0% 이상, 1.0%, 1.0%, 0.25% 이하, 1.0%, 1.0%, 2.0%, 1.0%, 1.0%, 0.5%였다.

• 한국식품과학회지
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• 제49권2호
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• pp.146-150
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• 2017

본 연구에서는 지금까지 거의 보고된 바 없는 corosolic acid의 항균활성에 대해 대표적 식중독균 중 하나인 S. aureus를 대상으로 연구하였다. 대수기의 S. aureus에 corosolic acid를 처리하여 생장 저해 여부를 확인하였고, broth micro-dilution 방법과 agar disc diffusion 방법을 통해 corosolic acid의 S. aureus에 대한 항균활성을 측정해본 결과, corosolic acid의 농도에 비례하여 S. aureus 생장이 저해되는 것으로 확인되었다. 또한 corosolic acid의 존재 조건에서 S. aureus의 바이오필름 형성능이 MIC 보다 높은 농도뿐 아니라 낮은 농도에서 역시 저해되는 것으로 관찰되었다. 따라서 천연물질인 corosolic acid는 S. aureus에 의한 식품 오염을 억제하고 식중독 예방 및 잠재적 치료제로서 개발 될 가능성이 있는 것으로 판단되며, 나아가 다른 종류의 식중독균들에 대한 적용 가능 연구가 필요할 것으로 사료된다.

• 한국컴퓨터정보학회논문지
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• 제21권5호
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• pp.135-139
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• 2016

Scrophularia ningpoensis hemsl has been traditionally used in China and Vietnam for treatment of bacteria, atopy, pimple, tonsillitis, angina and encephalitis for a long time. The main objectives of this study were to evaluate the antibacterial activity of the Scrophularia ningpoensis hemsl extract on biofilm formation of Klebsiella pneumoniae. Antibacterial activity was conducted using disc diffusion assay and minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) were determined using the broth micro dilution method in accordance to Clinical and Laboratory Standards Institute guidelines(CLSI). Furthermore, cytotoxicity on L929 were assessed using animal cell culture for the proliferation test(MTT cell assay) and the biofilm forming capacity of the K. pneumoniae were determined using the colony forming unit (CFU) assay. The extract exhibited considerable antibacterial activity. K. pneumoniae was susceptible to the extract with the MIC and MBC of 0.1875 and $1.5mg/m{\ell}$ respectively. Cytoxicity test in L929 showed no sign of toxicity at the concentration of $0.75mg/m{\ell}$ and at the same concentration the extract caused inhibition of bacterial biofilm formation. The extract of Scrophularia ningpoensis hemsl possesses an in vitro antibacterial antibiofilm activities against K. pneumoniae, with no sign of cytoxicity on L929.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2003년도 생물공학의 동향(XIII)
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• pp.740-744
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• 2003

The antimicrobial substance produced by Lactobacillus bulgaricus was inactivated by pretense, which confirmed it as a bacteriocin and referred to 'bulgaricin HJ'. The bulgaricin HJ showed the inhibitory activity against mastitis pathogens, gram-positive and gram-negative bacteria. The optimal conditions for the production of bulgaricin HJ were at the temperature of $30^{\circ}C$ and 10 h after cultivation of L. bulgaricus. Staph. and Strep. agalactiae, common bovine mastitis pathogens, were treated with bulgaricin HJ by the agar well diffusion method and showed antimirobial activities to the bovine mastitis pathogens. The activity of the bulgaricin HJ was maintained at pH 6-7 and $100^{\circ}C$ for 60 min against the mastitis pathogens. The bulgaricin HJ was determined as class IV bacteriocin by various enzyme treatments. Colony forming units analysis with indicator strains by the treatments of bulgaricin HJ indicates that the mode of bacteriocin action was bactericidal rather than bacteriostatic.

• 한국미생물·생명공학회지
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• 제48권4호
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• pp.429-438
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• 2020

The emergence of multi-drug resistant, pathogenic methicillin-resistant Staphylococcus aureus (MRSA) is a threat to global health and has created a need for novel functional therapeutic agents. In this study, we evaluated the underlying mechanisms of the anti-MRSA effect of an azaphilone pigment, sclerotiorin (SCL) from Penicillium sclerotiorum. The antimicrobial activity of SCL was evaluated using agar disc diffusion, broth microdilution, time-kill assays and biophysical studies. SCL exhibits selective activity against Gram positive bacteria including MRSA (range, MIC = 128-1028 ㎍/ml) and exhibited rapid bactericidal action against MRSA with a > 4 log reduction in colony forming units within three hours of administration. Biophysical studies, using fluorescent probes and laser or electron microscopy, demonstrated a SCL dose-dependent alternation in membrane potential (62.6 ± 5.0.4% inhibition) and integrity (> 95 ± 2.3%), and the release of UV260 absorbing materials within 60 min (up to 3.2 fold increase, p < 0.01) of exposure. Further, SCL localized to the cytoplasm and hydrolyzed plasmid DNA. While in vitro checkerboard studies revealed that SCL potentiated the antimicrobial activity of topical antimicrobials such as polymixin, neomycin, and bacitracin (Fractional Inhibitory Concentration Index range, 0.26-0.37). Taken together these results suggest that SCL targets the membrane and DNA of MRSA to facilitate its anti-MRSA antimicrobial effect.

• 한국축산식품학회지
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• 제40권4호
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• pp.668-674
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• 2020

Manuka honey (MH) has been shown anti-bacterial activity against several pathogenic bacteria. However, the inhibitory effect of MH on biofilm formation by Escherichia coli O157:H7 has not yet been examined. In this study, MH significantly reduced E. coli O157:H7 biofilm. Moreover, pre- and post-treatment with MH also significantly reduced E. coli O157:H7 biofilm. Cellular metabolic activities exhibited that the viability of E. coli O157:H7 biofilm cells was reduced in the presence of MH. Further, colony forming unit of MH-treated E. coli O157:H7 biofilm was significantly reduced by over 70%. Collectively, this study suggests the potential of anti-biofilm properties of MH which could be applied to control E. coli O157:H7.

• Asian-Australasian Journal of Animal Sciences
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• 제20권8호
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• pp.1190-1195
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• 2007

This study was conducted to improve efficiency of a follicle culture system without reducing developmental competence of intrafollicular oocytes. Preantral follicles (100 to $125{\mu}m$ in diameter) of F1 hybrid (B6CBAF1) mice were cultured singly for 216 h in modified ${\alpha}$-MEM-glutamax medium, to which 2.5 IU/ml hCG and epidermal growth factor was added 16 h prior to the end of culture. Medium change was either performed three times (54 h interval), twice (72 h interval), once (108 h interval), or not at all (216 h interval). Maturation (progression to the metaphase II stage) of intrafollicular oocytes was detected from 4 days after culture in the three-times change treatment, while all treatments yielded mature oocytes from day 5 of culture. Compared with the three-times change, decreasing the change frequency to once did not reduce the capacity to begin maturation (germinal vesicle breakdown of 82 to 86%), to mature (78 to 79%) and to develop into blastocysts after parthenogenetic activation (29 to 32%). Morphological parameters were similar among these treatments. Except for the no medium change treatment, similar colony-forming activity of inner cell mass cells after culturing of blastocysts in leukemia inhibitory factor-containing medium was detected, while the morphology of the colony-forming cells deteriorated in the change-once treatment compared with the change twice or three-times. In conclusion, the efficiency of the preantral follicle culture system could be improved by reducing frequency of medium change up to a 72 h interval (three times in total 216 h culture) without decreasing developmental competence of oocytes.