• Journal of Microbiology and Biotechnology
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• 제13권6호
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• pp.998-1000
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• 2003

This study was carried out to elucidate the mode of bacteriostatic property of xanthostatin (XS), a novel depsipeptide antibiotic with an N-acetylglycine side chain and selective antimicrobial activity against Xanthomonas spp. Two biotransformed XSs were isolated by the treatment of XS with the cell lysate of Xanthomonas campestris pv. citri, a solvent partition, preparative TLC, and HPLC. Structure determination of those two biotransformed XSs demonstrated deletion of the N-acetylglycine side chain. Noteworthily, they showed no antimicrobial activity against Xanthomonas spp. This result suggests that the N-acetylglycine side chain plays a critical role in the antimicrobial activity of XS, and that the bacteriostatic property of XS is due to susceptibility of the ester bond between the hexadepsipeptide nucleus and the N-acetylglycine side chain to hydrolytic enzyme(s) produced by Xanthomonas spp.

• 한국수산과학회지
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• 제23권5호
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• pp.394-400
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• 1990

수산제품의 처리, 가공에 사용되는 sodium poly-phosphate, sodium pyrophosphate, polymixer 등 의 사용시에 운반되어질 수 있는 가열, 동결, 금속염의 첨가 및 pH 변화에 따른 항균력 변화를 조사한 결과는 다음과 같다. 1. Sodium polyphosphate의 항균력은 $100^{\circ}C$ 이하에서의 가열에 의하여는 거의 영향을 받지 않았으나 121에서의 15분간 가열처리에 의하여 그 감퇴경향이 균종에 따라서 뚜렸하였다. 2. 중합인산염 함유 균체 현탁액의 가열 및 동결처리는 세균의 중합인산염에 대한 감수성을 증대시키는 것으로 나타났다. 3. 중합인산염의 항균력은 $CaCl_2$, KCl 및 $MgSO_4$ 등 금속염류의 첨가에 의하여 감퇴되었으며 이러한 항균력 감퇴를 유발시키는 금속염의 종류는 균종에 따라 달랐다. 4. 중합인삼염의 항균력은 대체로 pH 6.5 이하에서 강력하였다.

• 한국식품위생안전성학회지
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• 제23권1호
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• pp.68-72
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• 2008

Antimicrobial stability of grape seed extract ($ActiVin^{TM}$), pine bark extract ($Pycnogenol^{(R)}$), and oleoresin rosemary ($Herbalox^{(R)}$) on the growth of Aeromonas hydrophila was investigated in cooked ground beef. When compared to the control, the populations of A. hydrophila were most effectively reduced by 4.06 log CFU/g for 1% $Pycnogenol^{(R)}$ added after cooking at 10 days of refrigerated storage, followed by 3.06 log CFU/g for 1% $Pycnogenol^{(R)}$ added before cooking and 1.36 log CFU/g for $ActiVin^{TM}$. Bacteriostatic and bactericidal activities were observed for $Pycnogenol^{(R)}$ added before and after cooking, respectively. $Pycnogenol^{(R)}$ consists of heat-labile and heat-stable compounds. $ActiVin^{TM}$ and $Pycnogenol^{(R)}$ could be considered for use as multifunctional preservatives in meat and meat products.

• Preventive Nutrition and Food Science
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• 제14권2호
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• pp.162-167
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• 2009

Various fermented foods were screened in search of food-grade bacteria that produce bacteriocins active against Gram-negative pathogens. An isolate from a mold-ripened cheese presented antibacterial activity against Gram-positive and Gram-negative bacteria. The most active isolate was identified as Lactobacillus casei by a biochemical method, ribotyping, and membrane lipid analysis, and was designated as OSY-LB6A. The cell extracts of the isolate showed inhibition against Escherichia coli p220, E. coli O157, Salmonella enerica serovar Enteritidis, Salmonella Typhimurium, and Listeria monocytogenes. The antibacterial nature of the cell extract from the isolate was confirmed by eliminating the inhibitory effects of acid, hydrogen peroxide, and lytic bacteriophages. The culture supernatant and cell extract retained antibacterial activity after heating at $60{\sim}100^{\circ}C$ for $10{\sim}20$ min. The activity of the cell extract from Lb. casei was eliminated by pronase and lipase. Finally, the cell extract showed a bactericidal mode of action against E. coli in phosphate buffer solution, but it was bacteriostatic in broth medium and food extracts.

• 한국환경보건학회지
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• 제22권1호
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• pp.21-27
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• 1996

5.7-Dibromo-8-hydroxyquinolinyl-N-ethylcarbamate, one of the carbamate derivative which are generally used as insecticide, was newly synthesized. Its physical properities were determined and chemical structure was identified by means of I.R., nmr in addition to elemental analysis. The yield of addition, using triethylamine as catalyst, 5.7-dibromo-8-hydroxyquinoline and isocyanate was better than that of condensation of 5.7-dibromo-8-hydroxyquinoline with carbamoylchloride. The present organic synthesized compound showed the bacteriostatic action on salmonella typhi, escherichia coli and pseudomonas aeruginosa, but no otherwise effect of contraction of rabbit's ileum in the concentration of $100 \mu g/ml$.

• 한국환경보건학회지
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• 제22권2호
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• pp.19-24
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• 1996

Carbamates are generally used as insecticide, thus 5.7-dichloro-8~hydroxyquinolinyl- N-ethylcarbamate was newly synthesized. Its physical properties were determined and chemical structure was identified by means of I.R., nmr in addition to elemental analysis. The yield of addition, using triethylamine as catalyst, 5.7-dichloro-8-hydroxyquinoline and isocyanate was better than that of condensation of 5.7-dichloro-8-hydroxyquinoline with carbamoylchloride. The effct of the compound on rabbit's ileum, and antibacterial activity against Staphylococcus aureus, Salmonella typhi, Echerichia coli, and Pseudomonas aeruginosa were examined. The present organic synthesized compound showed the bacteriostatic action on salmonella typhi, escherichia coli, and pseudomonas aeruginosa, but no otherwise effect of contraction of rabbit's ileum in the concentration of $250 \mu g/ml$.

• 생약학회지
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• 제35권4호통권139호
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• pp.375-379
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• 2004

According to the traditional chinese herbal Cuscuta japonica Choisy and C. australis R.Be (original plant of Semen Cuscutae in Korea) have been used to cure pimple. In order to prove their bacteriostatic effects against Propionibacterium acnes, we performed the micro broth dilution method. The minimal inhibitory concentration (MIC) of C. japonica juice was 27.3 mg/ml, but C. australis juice showed no effect. The MIC of water extracted C. japonica seed and Wontosa and Bupjetosa were $960\;{\mu}g/ml$. The MIC of both water and ethanol extracts of C. australis seed was $9240\;{\mu}g/ml$. But ethanol extracts of C. japonicaseeds, Wontosa and Bupjetosa had no bacteriostatic activity. We also performed the disk diffusion test, C. japonica juice had prominent effect. Water extracts of C. japonica seed, Wontosa and Bupjetosa showed bacterio-static effect in 10 mg/ml, and C. australis seed in 10 mg/ml. The ethanol extract of C. japonica seed, Wontosa and Bupjetosa, and C. australis seed showed bacteriostatic effect in 20 mg/ml.

• 농업과학연구
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• 제21권2호
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• pp.122-132
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• 1994

본(本) 연구(硏究)는 초유(初乳) 중(中)에 다량(多量) 존재하면서, 국소면역(局所免疫)을 담당하고 있는 것으로 알려진 Secretory immumoglobulin A (SIgA)를 분리(分離)하여 사람에게 급성위장병 및 집단 식중독을 일으키는 장독소형(腸毒素型) Salmonella속(屬) (S. enteritidis, S. typhimurium)의 성장억제효과(成長抑制效果)를 시험하였다. 우유(牛乳) 초유(初乳) 중(中)에서 분리한 SIgA를 각각 $0.1{\sim}5.0mg/m{\ell}$의 수준이 되도록 stock solution을 제조하여 성장억제효과(成長抑制效果)를 비교 검토하였으며, 한편 항균성물질(抗菌性物質로)로 알려진 egg lysozyme을 $0.5mg/m{\ell}$의 수준으로 단독(單獨) 첨가(添加) 및 SIgA와 혼합(混合) 첨가(添加)하면서, 그에 따른 성장억제효과(成長抑制效果)를 검토(檢討)하였다. 1. 우유(牛乳) 초유(初乳) 중(中)에 존재(存在)하는 SIgA는 gel filtration 및 ion exchange chromatography 방법으로 순수하게 분리(分離)할 수 없었으며, 또한 SIgA rich fraction 중(中)에는 dimeric-$IgG_1$이 상당히 혼재(混在)되어 있는 것이 확인되었다. 2. Human SIgA는 $0.5{\sim}1.0mg/m{\ell}$의 농도(濃度)에서 효과적인 성장억제효과(成長抑制效果)를 보였으며, 그 이상의 농도(濃度)에서는 억제효과(抑制效果)의 증가추세가 둔화되었다. Bovine SIgA는 농도가 증가함에 따라 점진적인 성장억제효과(成長抑制效果)를 보였으며, 특히 $2.0mg/m{\ell}$이상의 농도(濃度)에서는 뛰어난 억제효과(抑制效果)를 보여 주었다. Bovine IgG는 Salmonella속 (屬) 2균주(菌株)에 대하여 성장억제효과(成長抑制效果)를 보이지 않았다. Egg lysozyme의 성장억제효과(成長抑制效果)는 bovine SIgA와 비슷한 경향을 나타냈으며 농도(濃度)를 증가시킬수록 억제효과(抑制效果)가 증가(增加)하는 경향을 보여 주었다. 3. Human SIgA와 egg lysozyme을 단독(單獨) 또는 혼합첨가(混合添加)하면서 시간 경과에 따른 성장억제효과(成長抑制效果)를 시험한 결과, 2균주(菌株) 모두에서 egg lysozyme은 대조구(對照區)에 비하여 월등한 성장억제효과(成長抑制效果)를 나타내는 반면 human SIgA 단독(單獨) 및 egg lysozyme과 혼합처리구(混合處理區)에는 경미한 억제효과(抑制效果)를 나타내었다. 4. Bovine SIgA와 egg lysozyme을 단독(單獨) 또는 혼합(混合) 첨가(添加)하면서 시간경과에 따른 성장억제효과(成長抑制效果)를 시험한 결과, S. enteritidis의 경우 세처리구 모두 월등한 성장억제(成長抑制)를 보였으며, S. typhimurium의 경우 egg lysozyme 단독처리구(單獨處理區)만 뛰어난 성장억제효과(成長抑制效果)를 보여 주었다.

• Biomaterials and Biomechanics in Bioengineering
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• 제2권3호
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• pp.159-172
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• 2015

Treatment of polymicrobial infected musculoskeletal defects continues to be a challenge in orthopaedics. This research investigated single and dual-delivery of two antibiotics, vancomycin and amikacin, targeting different classes of microorganism from a biodegradable calcium sulfate-chitosan-nHA microsphere composite scaffold. The addition of chitosan-nHA was included to provide additional structure for cellular attachment and as a secondary drug-loading device. All scaffolds exhibited an initial burst of antibiotics, but groups containing chitosan reduced the burst for amikacin at 1hr by 50%, and vancomycin by 14-25% over the first 2 days. Extended elution was present in groups containing chitosan; amikacin was above MIC ($2-4{\mu}g/mL$, Pseudomonas aeruginosa) for 7-42 days and vancomycin was above MIC ($0.5-1{\mu}g/mL$ Staphylococcus aureus) for 42 days. The antibiotic activity of the eluates was tested against S. aureus and P. aeruginosa. The elution from the dual-loaded scaffold was most effective against S. aureus (bacteriostatic 34 days and bactericidal 27 days), compared to vancomycin-loaded scaffolds (bacteriostatic and bactericidal 14 days). The dual- and amikacin-loaded scaffolds were effective against P. aeruginosa, but eluates exhibited very short antibacterial properties; only 24 hours bacteriostatic and 1-5 hours bactericidal activity. For all groups, vancomycin recovery was near 100% whereas the amikacin recovery was 41%. In conclusion, in the presence of chitosan-nHA microspheres, the dual-antibiotic loaded scaffold was able to sustain an extended vancomycin elution longer than individually loaded scaffolds. The composite scaffold shows promise as a dual-drug delivery system for infected orthopaedic wounds and overcomes some deficits of other dual-delivery systems by extending the antibiotic release.

• Journal of Microbiology and Biotechnology
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• 제32권4호
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• pp.522-530
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• 2022

In this study we aimed to develop novel ZnO-NP/chitosan/β-glycerophosphate (ZnO-NP/CS/β-GP) antibacterial hydrogels for biomedical applications. According to the mass fraction ratio of ZnO-NPs to chitosan, mixtures of 1, 3, and 5% ZnO-NPs/CS/β-GP were prepared. Using the test-tube inversion method, scanning electron microscopy and Fourier-transform infrared spectroscopy, the influence of ZnO-NPs on gelation time, chemical composition, and cross-sectional microstructures were evaluated. Adding ZnO-NPs significantly improved the hydrogel's antibacterial activity as determined by bacteriostatic zone and colony counting. The hydrogel's bacteriostatic mechanism was investigated using live/dead fluorescent staining and scanning electron microscopy. In addition, crystal violet staining and MTT assay demonstrated that ZnO-NPs/CS/β-GP exhibited good antibacterial activity in inhibiting the formation of biofilms and eradicating existing biofilms. CCK-8 and live/dead cell staining methods revealed that the cell viability of gingival fibroblasts (L929) cocultured with hydrogel in each group was above 90% after 24, 48, and 72 h. These results suggest that ZnO-NPs improve the temperature sensitivity and bacteriostatic performance of chitosan/β-glycerophosphate (CS/β-GP), which could be injected into the periodontal pocket in solution form and quickly transformed into hydrogel adhesion on the gingiva, allowing for a straightforward and convenient procedure. In conclusion, ZnO-NP/CS/β-GP thermosensitive hydrogels could be expected to be utilized as adjuvant drugs for clinical prevention and treatment of peri-implant inflammation.