• 한국생물공학회:학술대회논문집
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• 2003.10a
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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.

• Biomolecules & Therapeutics
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• v.1 no.2
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• pp.196-203
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• 1993

We compared in vitro antibacterial activity of DWC-751, a new parenteral cephalosporin antibiotic, with those of cefpirome (CPR), cefotaxime (CTX) and ceftazidime (CAZ). DWC-751 showed a broad antimicrobial spectrum against Gram-positive and negative bacteria. The antibacterial activity of DWC-751 against Stapylococcus aureus was equal to that of CPR and superior to those of CTX and CAZ. The activity of it against Excherichia coli was more potent than those of CPR, CTX and CAZ. Against Pseudomonas aeruginosa, DWC-751 was slightly inferior to that of CAZ and superior to those of CPR and CTX. The antibacterial activity of DWC-751 was superior to those of CPR, CTX and CAZ against clinical isolates and ofloxacin resistant strains. DWC-751 showed bactericidal action against Escherichia coli at concentrations close to the MIC and induced the formation of filament and burge and lysis of Escherichia coli in a microscopic examination.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.04a
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• pp.12-12
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• 1997

CFC-222 is a novel fluoroqinolone antibacterial agent synthesized and under development by the Cheil Jedang Corporation, Korea. CFC-222 exerts the antibacterial activity by inhibition of bacterial DNA gyrase leading to bactericidal action. In in vitro and in vivo preclinical testing, CFC-222 has been shown to possess a broad spectrum of antibacterial activity. In particular CFC-222 is very potent against Gram-positive bacteria such as Staphylococcus spp., Streptocuccus spp. (in particular penicillin G-resistant and -susceptible S. pneumoniae) and Enterococcus spp. when compared to other quinolones (ciprofloxacin, ofloxacin or lomefloxacin). CFC-222 also showed potent activity against the methicillin resistant clinical isolates of S. aureus (MRSA). Against Gram-negative bacteria (E. coli, Pseudomonas and Sarcina) the activity of CFC-222 was slightly weaker than that of ciprofloxacin, but was more potent than that of ofloxacin or lomefloxacin. In urinary systemic infections caused by both Gram-positive and -negative bacteria, CFC-222 demonstrated a potent therapeutic efficacy in particular against Cram-positive bacteria S. aureus, S. pyrogen 203 and S. pneumonia TypeIII.

• Journal of Microbiology and Biotechnology
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• v.10 no.4
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• pp.539-543
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• 2000

A new bacteriocin, named lacticin 10790, was purified from Lactococcus lactis subsp. cremoris KFCC 10790 by sequential adsorption, immobilized metal-affinity, cation-exchange, and $C_{18}$ reverse-phase chromatographies. The molecular mass of the bacteriocin was estimated to be between 3,000 and 3,500 Da. Lacticin 10790 showed a broad antimicrobial spectrum against many gram-positive bacteria. The bacteriocin was stable to heat and in the pH range between 2 and 6. Lacticin 10790 was destroyed by digestion with proteases and exhibited a bactericidal mode of action. An amino acid composition analysis of purified lacticin 10790 revealed a high concentration of hydrophobic amino acids. The N terminus of the bacteriocin was found to be blocked, upon analysis by Edman degradation. The results suggest that lacticin 10790 is a class I bacteriocin.

• Food Science and Biotechnology
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• v.18 no.4
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• pp.833-841
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• 2009

Monoterpenes, in special limonene and its derivatives, are well studied in the literature due to their several properties. They are well recognized as major components of essential oils; some of them, are important industry residues, and others present some important biological activities. In this review, the biotransformation of the inexpensive limonene into flavor compounds was briefly reviewed and the main pathways for limonene biotransformation are presented. Furthermore, some important biological properties of these compounds were also considered, like bactericidal activity, induction of immune response, and role in disease prevention, with a little emphasis on some possibilities related to the mechanisms of anticancer action.

• Food Science of Animal Resources
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• v.36 no.4
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• pp.452-457
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• 2016

Lactoferrin is a glycoprotein with various biological effects, with antibacterial activity being one of the first effects reported. This glycoprotein suppresses bacterial growth through bacteriostatic or bactericidal action. It also stimulates the growth of certain kinds of bacteria such as lactic acid bacteria and bifidobacteria. In this study, Asn-Leu-Asn-Arg was selected and chemically synthesized based on the partial sequences of bovine lactoferrin tryptic fragments. Synthetic Asn-Leu-Asn-Arg suppressed the growth of Pseudomonas fluorescens, P. syringae and Escherichia coli. P. fluorescens is a major psychrotrophic bacteria found in raw and pasteurized milk, which decreases milk quality. P. syringae is a harmful infectious bacterium that damages plants. However, synthetic Asn-Leu-Asn-Arg did not inhibit the growth of Lactobacillus acidophilus. It is expected that this synthetic peptide would be the first peptide sequence from the bovine lactoferrin C-lobe that shows antibacterial activity.

• Food Science of Animal Resources
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• v.35 no.1
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• pp.137-142
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• 2015

A lactic acid bacterium presenting antimicrobial activity against a Lactobacillus acidophilus strain used for eradication of acid inhibition was isolated from a natural cheese. The 16S rRNA gene sequence of the isolate best matched with a strain of L. rhamnosus and was designated L. rhamnosus CJNU 0519. The antimicrobial activity of the partially purified bacteriocin of CJNU 0519 was abolished when treated with a protease, indicating the protein nature of the bacteriocin. The partially purified bacteriocin (rhamnocin 519) displayed a narrow antimicrobial activity against L. acidophilus, Listeria monocytogenes, and Staphylococcus aureus among several tested bacterial and yeast strains. Rhamnocin 519 in particular showed strong bactericidal action against L. monocytogenes.

• The Journal of the Korean Society for Microbiology
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• v.13 no.1
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• pp.75-79
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• 1978

There has been many investigations on phytoagglutinin and especially, Moon et al reported a number of research works on phytoagglutinins prepared from the Korean plants. The present report describes results of experiment on the biological effect of 14 Korean phytoagglutinins to microorganism for the first time. 1) Kaolin rubi and Ricinus communis L. among 14 different species of Korean phytoagglutinins had agglutinating activities to microoganisms. 2) Kaolin rubi agglutinated E. coli, Staph. aureus, Ps. aeruginosa, Prot. vulgaris, B. subtilis, Sal. typhi, Sh. dysenteriae, C. albicans and Sa. cerevisiae but Ricinus communis L. showed only agglutination of Sa. cerevisiae. 3) Agglutinating titers of Kaolin rubi to various microorganisms were 500-1,000 but titer of Ricinus communis L. was only 50. 4) Ricinus communis L. showed bactericidal action to Sa. cerevisiae but Kaolin rubi had no such effect.

• Food Science and Biotechnology
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• v.14 no.5
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• pp.581-585
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• 2005

The antimicrobial activity of partially purified enterocin K25, produced by Enterococcus sp. K25, was abolished by proteases such as pepsin and proteinase K. The bacteriocin was resistant to heat treatment at $75^{\circ}C$ for 15 min and lost 75% of its activity at $100^{\circ}C$ for 30 min. Enterocin K25 showed bactericidal mode of action against an indicator strain, Lactobacillus plantarum NCDO 955. Enterocin K25 was purified to 112.6-fold purity via conventional steps of ammonium sulfate precipitation, ion exchange chromatography, and reversed phase high performance liquid chromatography (RP-HPLC). The molecular mass of the purified enterocin K25 was estimated as 4.3 kDa on an electrophoresis gel. Plasmid (${\sim}6.5\;kb$) linkage of production of enterocin K25 was confirmed by plasmid curing.

• Food Science of Animal Resources
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• v.41 no.1
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• pp.164-171
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• 2021

Listeria monocytogenes is a representative foodborne pathogen and causes listeriosis. Enterococcus faecium CJNU 2524 was confirmed to produce a bacteriocin with anti-listerial activity. To establish optimal culture conditions for the production of the bacteriocin from E. faecium CJNU 2524, different media (MRS and BHI broth) and temperatures (25℃, 30℃, and 37℃) were investigated. The results showed that the optimal culture conditions were MRS broth and 25℃ or 30℃ temperatures. The crude bacteriocin was stable in a broad range of pH conditions (2.0-10.0), temperatures (60℃-100℃), and organic solvents (methanol, ethanol, acetone, acetonitrile, and chloroform). The bacteriocin activity was abolished when treated with protease but not α-amylase or lipase, indicating the proteinaceous nature of the bacteriocin. Finally, the bacteriocin showed a bactericidal mode of action against L. monocytogenes. Therefore, it can be a biopreservative candidate for controlling L. monocytogenes in dairy and meat products.