• 대한미생물학회지
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• 제19권1호
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• pp.41-48
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• 1984

The present study was undertaken to elucidate the antibacterial spectrum of L. casei phage type $J_1$ strain isolated from a fermented milk product against pathogenic enteric bacteria. Growth inhibitory effects and minimum inhibitory concentration(MIC) of culture supernatants of L. casei grown in MRS broth were measured by both plate culture method and microplate broth dilution technique against Salmonella typhi, Salmonella typhimurium, Shigella flexneri, Shigella dysenteriae, enterpathogenic E. coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. The results are summarized as follows: 1. The MRS broth culture of L. casei gave a similar extent of growth inhibitory effects against S. typhi, S. typhimurium, S. flexneri, S. dysenteriae, E. coli, K. pneumoniae and P. aeruginosa, respectively. 2. The inhibitory effects of L. casei culture were observed either in whole broth culture or in culture supernatant, but neither the bacterial suspension nor the neutralized culture supernatant showed such as antibacterial activities. 3. The MIC titres of the culture supernatants were ${\log_2}5$ to ${\log_2}6$, whereas those of the neutralized culture supernatant dropped markdely to ${\log_2}2$ to ${\log_2}3$. These results indicated that major portion of growth inhibitory effects of MRS broth culture of L. casei against enteric bacterial pathogens was possibly due to the acids produced, and minor portion to other antibacterial substances.

• Fisheries and Aquatic Sciences
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• 제22권6호
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• pp.13.1-13.9
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• 2019

Background: Marine invertebrates are well known as pivotal bioresources with bioactive substances such as anti-inflammatory sterols, antitumor terpenes, and antimicrobial peptides. However, there are few scientific reports on chemical compositions and bioactivities of marine invertebrates from the East Sea of South Korea. Methods: In this study, chemical compositions and biological activities were evaluated on both 70% EtOH and hot water extracts of 5 species of marine invertebrates (Crossaster papposus japonicus, Actinostola carlgreni, Stomphia coccinea, Actinostola sp., and Heliometra glacialis) collected from the East Sea of South Korea. The antioxidant activities were measured by ABTS radical scavenging assay. The cytotoxicity and anti-inflammatory activity were evaluated using MTT and Griess reagents. Moreover, the antibacterial effect was evaluated using paper disc assay and minimum inhibitory concentration (MIC) assay. Results: In the results of antioxidant activities, 70% EtOH extract of A. carlgreni showed the highest activity ($IC_{50}\;0.19{\pm}0.03mg/ml$) compared to other extracts. Moreover, 70% EtOH extract of A. carlgreni could significantly suppress the nitric oxide (NO) production in lipopolysaccharide-induced RAW 264.7. All extracts treated under $400{\mu}g/ml$ have no cytotoxic effects on RAW 264.7 macrophages. In the antibacterial test, both 70% EtOH extracts of C. papposus japonicus and H. glacialis showed a significant antibacterial effect on Staphylococcus aureus. The MIC values were evaluated at 256 and $512{\mu}g/ml$, respectively. Conclusions: These results suggested the bioactive potentials of marine invertebrates from the East Sea of South Korea in pharmaceutical and nutraceutical applications.

• 한국표면공학회지
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• 제54권3호
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• pp.144-151
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• 2021

In the present work, planar-type ZnO powder of [0001] plane with a high aspect ratio range of 20:1 to 50:1 was synthesized. Ag or CuO could be coated on the planar-type ZnO powder by wet methods such as centrifugation or ball milling. During the coating, the average size of the powder was slightly increased while maintaining the shape and XRD pattern of ZnO. When Ag or CuO was coated, the absolute value of the zeta potential, as well as the concentration of oxygen vacancy, was increased. Ag or CuO coated planar-type ZnO power exhibited excellent antibacterial performance, which seems to be related to their high electrostatic attraction force. They could be made into a masterbatch by mixing with ABS resin, and their applicability to antibacterial substances was confirmed by manufacturing the caps of a keyboard.

• Journal of Animal Science and Technology
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• 제65권1호
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• pp.225-243
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• 2023

Large amounts of additives are used during meat product processing to maintain product quality and shelf life. With the growing interest in healthy foods, natural plant-based additives are being used as alternatives to synthetic additives. In this study, six types of natural extracts with excellent antibacterial activity were selected, and their antibacterial and antioxidant activities against four types of pathogens were evaluated in various combinations. In addition, the pH, color, amount of thiobarbituric acid reactive substances (TBARS), and growth of pathogenic microorganisms were analyzed during the storage of sausages treated with various combinations of these extracts. The natural extract mixtures exhibited different antibacterial activities, depending on the combination. Compared to grapefruit seed extract, a mixture of natural extracts extracted with ethanol (M4) reduced the Escherichia coli content by more than 99.9% after 8 days of storage and slowed the growth of Listeria monocytogenes and Salmonella spp. by more than 80% after 14 days. Compared to untreated (NC) and grapefruit extract (PC)-treated sausages, sausages treated with the natural extract mixtures showed a significant decrease in CIE L^* and an increase in CIE a^* and CIE b^* (p < 0.05). The pH value was significantly lower in sausages containing natural extract mixtures than in the NC and PC sausages (p < 0.05). The natural plant extract mixtures significantly prevented lipid oxidation (p < 0.05). In summary, different types of natural extract mixtures have a synergistic effect when used together, suggesting that natural preservatives can generally inhibit the growth of microorganisms and oxidation of processed meat.

• 한국미생물·생명공학회지
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• 제41권1호
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• pp.44-51
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• 2013

국내 토양시료에서 분리한 174 Corallococcus 속 균주와 207 Myxococcus 속 균주들의 배양추출물을 제조하고 Candida albicans, Pseudomonas aeruginosa, Staphylococcus aureus에 대한 항균 활성을 비교하였다. 항진균 활성을 보이는 균주의 비율은 Corallococcus가 7.5%(174균주 중 13균주)로 51.7%(207균주 중 107균주)를 보인 Myxococcus에 비해 낮았다. 하지만, 항세균 활성을 보인 균주의 비율은 Corallococcus가 12.1%(21균주)로 1%(2균주)를 보인 Myxococcus에 비해 상대적으로 높았다. Corallococcus 균주 중 P. aeruginosa, S. aureus에 모두 활성을 보이는 6 C. coralloides 균주들은 자실체 형성에서는 차이를 보였지만 항세균 활성을 나타내는 배양추출물의 HPLC 크로마토그램은 유사하였는데, 이들이 생산하는 항세균 물질의 생산은 CYS 배지에서 6일 이상 배양할 때 가장 높았다.

• Preventive Nutrition and Food Science
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• 제2권2호
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• pp.109-120
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• 1997

In order to elucidate roles of lactic acid bacteria(LAB) for the antibiosis occurring in th fermenting environment of Kimchi, 2.052 strains of LAB were isolated from Kimchi. Fifty tow strains which showed antagonistic effect against 4 indicator strains were finally selected and investigated. Based upon responses to protease treatment, antibiosis of the 52 strains of LAB were classified into 3 types. Type A antibiosis resulted from action of antibiotic-like substances which were not affected by protease treatment and which had broad action spectra against even natural inhabitants of Kimchi. Type B antibiosis was due to bacteriocin-like substances which were very sensitive to treatment of protease and more effective against foreign bacteria than original inhabitant microflora. Type C antibiosis was owing to proteinaceous compounds which were activated or induced by the presence of protease and then exerted antibacterial activities. Therefore, lactic acid bacteria appeared to contribute to antibiosis of Kimchi by the concerted action of these three different types of antibacterial compounds. As one of model system for type B bacteriocin, the antagonistic compound produced by LAB31-9 as well as th producer strain itself was further charaacterized. Strain LAB31-9 was identified as L. casei. Bacteriocin produced by LAB31-9 was proteinaceous and stable over wide range of pH and to various solvents, but very labile to heat treatment. Its mode of action was bactericidal. Based upon these data, bacteriocin produced by LAB31-9 was named as 'caseicin K319'. Genetic determinant for the bacteriocin production of LAB31-9 was located in the chromosome.

• 한국식품저장유통학회지
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• 제16권6호
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• pp.924-928
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• 2009

녹차에 관한 최근까지의 연구결과에서, 녹차는 생리활성의 촉진작용뿐아니라 항암, 항산화, 고혈압 억제효과, 체중 조절 등 다방면의 약리효과를 보이는 것으로 보고되고 있다. 아울러, 녹차의 항균 및 항진균 작용에 관한 연구결과도 발표되고 있으며, 본 연구팀에 의해서도 녹차추출물의 항균작용을 확인한 바 있어, 본 연구에서는 탁월한 항균작용을 소유하고 있는 녹차분획물질을 분리하여 그 분자구조를 동정하는데 목적이 있다. 따라서, 녹차추출물에서 탁월한 항균력을 가지는 항균활성물질을 HPLC 분리방법 및 NMR 분석법으로 분리 동정한 결과, 각각 (-)-epicatechin gallate 및 (-)-epigallocatechin gallate로 확인되었다.

• 한국염색가공학회지
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• 제20권6호
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• pp.18-25
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• 2008

The functional non-woven fabrics have been applied in various industry fields, such as clothing, hygiene, environment, medical and so forth. The functional non-woven fabrics were manufactured by meltblown and finishing processes. These functional non-woven fabrics were based on 5wt% masterbatch using 2,000ppm nano-silver resin composite. Silver is one of the most universal antimicrobial substances. Nano-technology enables us to expand the surface area of silver particles markedly. Silver nano particles were successfully produced less than 50nm in size. The functional non-woven fabrics including nano-silver particles showed excellent antibacterial activities against Staphylococcus aureus (ATCC 6538) and Klebsieila pneumoniae (ATCC 4352). From the results, functional non-woven fabrics including silver nano particels probably will be available as a good and safe antibiotic alternative, such as mask medium filter, water purifier filter, hygiene wet tissues, marine products pad and so forth.

• 한국식품과학회지
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• 제24권6호
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• pp.552-557
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• 1992

영지추출액의 세균, 효모, 곰팡이에 대한 항균활성을 cup cylinder method와 MIC로 검색한 결과 세균에 대해서만 활성을 나타내었으며 그 중에서 영지의 ethylacetate fraction B와 fraction E에서 강한 활성을 보였다. Fraction B는 Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Salmonella typtimurium 및 Pseudomonas aeruginosa 등에서 활성을 나타냈고 특히 Staphylococcus aureus와 Salmonella typtimurium에 대한 최소저해농도(MIC)는 0.8%(8,000 ppm)로 향신료로 사용되는 celery가 Staphylococcus aureus에 대하여 10,000 ppm인 것과 유사하였다. Fraction E는 Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Salmonella typtimurium에서 활성을 나타내었고, 특히 Staphylococcus aurues에 대한 최소저해농도(MIC)는 0.187%(1,875 ppm)로 향신료로 사용되는 rosmary가 Staphylococcus aureus에 대하여 MIC가 5,000 ppm인데 비하여 약간 강한 항균활성을 나타내었다.

• 한국식품과학회지
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• 제29권2호
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• pp.348-354
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• 1997

본 연구는 여러가지 유해세균과 인체장암세포에 대한 다양한 농도에서의 마늘 추출물의 효과를 고양하고자 계획하였다. 미생물에 대한 항균효과는 그 최소 발육저지농도가 alliin의 경우에는 $5,000{\sim}20,000\;ppm$, 그리고 ethanol extract의 경우에는 $1,250{\sim}10,000\;ppm$이었으며, 또한 이들 성분의 암세포증식억제는 첨가농도가 증가함에 따라 점차 강하게 억제시킴을 알 수 있었다. 그리고 HCT-15의 형태적 관찰에서도 위축됨을 알 수 있었으며, 위의 결과들로 부터 항균과 암세포증식억제에 있어서의 활성물질은 열에 안정하고 에탄올에 의해 추출되는 성분임을 알 수 있었다.