• 대한수의학회지
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• 제33권3호
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• pp.393-406
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• 1993

Antibacterial substances produced by Lactobacillus casei subsp. and Streptococcus faecium were examined for its antibacterial effects against some pathogenic bacteria. They were partially purified with ammonium sulfate precipitation, methanol-acetone extraction, G-50 gel filtration and examined its characteristics. When L casei subsp. and Str faecium were cultivated in MRS broth, stationary phase of L casei is until 24 hours and Str faecium is 20 hours. pH change of the cultured medium was both decreased after 12 hours and then constant at pH 4.5~4.6 after 28 hours. MRS broth culture fluids of L casei subsp. and Str faecium appeared the antibacterial effects by the spot-on-the-lawn method against ETEC, Sal pullorum and Sta aureus. Culture filtrates of L casei subsp. and Str faecium also appeared the antibacterial effects by the disc diffusion method. Culture filtrates of L casei sub. rhamnosus 7469 produced 0.032M of lactic acid and 0.01M of acetic acid. Str faecium 27273 also produced 0.027M of lactic acid and 0.01M of acetic acid. Protein concentrations of culture filtrates produced by L casei sub rhamnosus 7469 and Str faecium 27273 was $495{\mu}g/m{\ell}$ and $594{\mu}g/m{\ell}$, respectively. Antibacterial substances which are partially purified by ammonum sulfate precipitation, methanol-acetone extraction and G-50 gel filtration inhibit the growth of ETEC, Sal pullorum and Sta aureus. Characteristics of purified antibacterial substances was examined. Its molecular weight was about 31Kd, stabilized at $100^{\circ}C/20min.$ and some of proteolytic enzyme treatment.

• 급식외식위생학회지
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• 제1권1호
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• pp.27-35
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• 2020

Salt is a common seasoning agent used in various processed foods, especially in kimchi and salted seafood (jeotgal). This study was conducted to investigate the efficacy of salt with antimicrobial substances (acetic acid, garlic extract, carvacrol, nisin, thymol, and their combination (acetic acid+nisin+thymol)) on improvement of antibacterial effects of salt against foodborne pathogens. Salt (10%) was prepared using six different types of 0.2% natural antimicrobial substances. The antibacterial effect of salt combined with natural antimicrobial substances was evaluated against foodborne pathogens using the broth micro-dilution method and growth curve plotted using absorbance measurements. For the five foodborne pathogens, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of salt without antimicrobial substances as control were in the range of 24~>50,000 ㎍/mL and >50,000 ㎍/mL, respectively. Salt with nisin, thymol, or garlic extract showed strong inhibitory effects and their MIC against L. monocytogenes were 49, 12,500, and 24 ㎍/mL, respectively. In particular, salt with nisin showed inhibitory activities against Gram-positive bacteria. However, all the antimicrobial substances were less effective against Gram-negative bacteria such as E. coli O157:H7 and S. Typhimurium than Gram-positive bacteria. These results could be used for the development of salt with natural antimicrobial substances especially targeted against L. monocytogenes. This would enable the lowering of saline concentration while improving the storability of food.

• Journal of Microbiology and Biotechnology
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• 제19권1호
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• pp.42-50
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• 2009

Fifty-four Pectobacterium carotovorum subsp. carotovorum strains isolated in Korea were characterized by a spectrum of antibacterial activities against 7 indicator strains chosen to represent various regions and host plants. All P. carotovorum subsp. carotovorum isolates tested could be grouped into 4 classes depending on the pattern of antibacterial substance production. All tested strains had DNA fragment(s) homologous to the genes encoding carotovoricin and 21 of them had genes homologous to DNA invertase. Sixteen strains had genes homologous to the genes encoding carocin S1. Several isolates produced antibacterial substances active against strains in Brenneria, Pantoea, and Pectobacterium genera that belonged formerly to the genus Erwinia. Strains in Pseudomonas or Xanthomonas sp. were not sensitive to the antibacterial substances produced by P. carotovorum subsp. carotovorum, except for X. albilineans that was sensitive to antibacterial substances produced by most strains in P. carotovorum subsp. carotovorum and P. betavasculorum KACC10056. These results demonstrated the diverse patterns of antibacterial substance production and the possibility of the existence of new antibacterial substance(s) produced by P. carotovorum subsp. carotovorum isolated in Korea.

• 한국염색가공학회지
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• 제32권4호
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• pp.232-238
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• 2020

Duck down is a feather of waterfowl and is used as an accessory for bedding products such as evil, pillow and outdoor sleeping bags due to its soft and bulky characteristics. Down is used mainly for winter outdoor such as padding and jumpers because of its excellent thermal insulation effect. Down wear is known as a product with high added value. Down is processed and sanitized because a large amount of oil and fat, bacteria, dust, insects, and soil are mixed. In particular, if the proper amount of oil and fat is not removed, it may cause odor or bacteria, and since the fishy smell peculiar to down and harmful VOCs (toluene, benzene, etc.) are released, there is a need to suppress the occurrence of bacteria through the provision of antibacterial function. In this study, we investigated the substances that cause the fishy odor of down, and confirmed the effect on the deodorization and antibacterial properties of down according to processing agents and processing conditions in order to impart deodorant and antibacterial properties to down.

• 한국어병학회지
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• 제28권1호
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• pp.17-26
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• 2015

The purpose of this study is to explore the possibility of essential oils and flavonoids improving the performance of antibiotics, proving a higher efficacy in the presence of natural substances against Edwardsiella tarda and Streptococcus iniae. Increased efficacy was observed in several cases: both essential oils and flavonoids increased antibacterial efficacy of oxytetracycline and flumequine against E. tarda by 2-fold; essential oils and flavonoids increased antibacterial efficacy of nalidixic acid against E. tarda by 4-fold; flavonoids increased antibacterial efficacy of josamycin against S. iniae by 4-fold. The results obtained in this study suggest that essential oils and flavonoids might be especially useful in increasing the antimicrobial activity of nalidixic acid and josamycin against E. tarda and S. iniae in fish. Natural compounds examined in this study could also be useful to help decrease the overuse of antibiotics in fish.

• 대한수의학회지
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• 제45권1호
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• pp.113-119
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• 2005

Resistance to antibiotics is a problem all over the world, and this problem also is so extended in veterinary fields. Therefore, this study aimed to find out the antibacterial substances from natural medicinal herbs against bovine mastitis pathogens, especially methicillin-resistant Staphylococcus aureus (MRSA). Among seventy two medicinal herbs, Terminaliae chebula extract showed antimicrobial effect against MRSA isolated from mastitis milk in cow and patient in human. However, Terminaliae chebula extract didn't show antibacterial effects on various strains including other contagious and environmental pathogens related with mastitis of dairy cows.

• 미생물학회지
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• 제54권3호
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• pp.272-279
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• 2018

본 연구는 여드름을 유발하는 세균인 Propionibacterium acnes에 대해 다양한 토양에서 분리된 세균 균주들의 항균효과를 조사하기 위해 수행되었다. 수백 개의 분리 세균균주 중 Paenibacillus elgii DS381과 Paenibacillus elgii DS1515, Burkhoderia gladioli DS518, Streptomyces lienomycini DS620는 2가지 균주의 P. acnes에 대해 높은 항균활성을 나타내었다. 이 분리균주들은 agar well diffusion test에서 15.5~34.3 mm 직경의 저해대를 형성하였으며, 특히 DS620는 가장 큰 저해대 직경(28.3~34.3 mm)을 나타내었다. 분리 균주가 생성하는 항균 물질은 DS381과 DS1515 균주의 경우lipopeptide (pelgipeptin, paenipeptin), DS518은 protease, 그리고 DS620은 anthracycline 인 것으로 추정되며, 이들 모두 P. acnes에 대해매우낮은 최소저해농도를 나타내었다[DS381와 DS1515 (0.078 mg/ml), DS518 (0.312 mg/ml), DS620 (0.000078 mg/ml)]. P. acnes를 대상으로 한 time-kill assay에서는 네 균주의 항균물질이 모두 24시간 이내에 P. acnes를 완전히 사멸시켰다. 이 결과는 네 가지 항균활성 균주들이 분비하는 항균물질들이 여드름을 유발하는 P. acnes에 대하여 효율적인 치료 소재로 사용될 수 있는 가능성을 보여준다.

• 한국식물병리학회지
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• 제3권3호
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• pp.203-209
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• 1987

Pseudomonas solanacearum의 병원성균주 및 비병원성균주를 담배의 뿌리에 접종하여 그 잎과 줄기, 뿌리에서 P. solanacearum과 Erwinia carotovora subsp. carotovora, Escherichia coli에 대한 항균물질을 분리하였다. 담배즙액을 TLC plate에 발전시킨 결과 비병원성균주에 접종된 담배에서는 $R_f$ 0.6 부근에서, 병운성균주에 접종된 담배에서는 $R_f$ 0.9 부근에서 각각 항균물질을 분리할 수 있았다. 그러나 고압살균된 담배즙액배지에 병원성균주 및 비병원성균주를 3일간 배양한 배양여액에서는 항균물질의 생성이 인정되지 않았다. 비병원성균주 및 병원성균주에 접종된 담배잎에서는 무처리 담배에 비하여 peroxidase와 polyph-enoloxidase의 활성이 높았으나, 그 줄기와 뿌리에서는 효소활성의 차이가 없었다. 비병원성균주와 병원성균주로 처리된 담배 사이, 감수성품종인 BY4와 저항성품종 NC82 사이에도 두 효소의 활성과 동위효소형태의 차이가 없었다.

• 대한의생명과학회지
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• 제15권1호
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• pp.73-80
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• 2009

Bloodstream infections (BSI) are caused by planktonic microorganisms, sometimes leading to serious infections such as bacteremia and sepsis. BSI occurs more frequently to the patients wearing the central venous catheter (CVC). The ciprofloxacin-incorporated CVC (CFX-CVC) has been reported previously to possess antimicrobial activity. In this study, the antibacterial activity of CFX-CVC and its mechanism against planktonic BSI cells were explored by using the shake flask test and by examining the release rate of 260 nm-absorbing substances from the bacterial cells indicative of the membrane damage of the bacterial cells. CFX-CVC reduced more than 99.9% of the viable planktonic BSI cells demonstrating its potent antibacterial activity. It provoked bacteriolysis causing leakage of a large amount of 260 nm-absorbing materials from the planktonic bacterial cells like S. aureus and E. coli. These results provide evidence that the antibacterial activity of CFX-CVC came from the inhibition of the stability of the planktonic bacterial cells.

• 동의생리병리학회지
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• 제34권4호
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• pp.184-190
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• 2020

This study was performed to find antibacterial substances contained in Scutellariae Radix (SR) using a systems pharmacological analysis method and to establish an effective strategy for the prevention and treatment of infectious diseases. Analysis of the main active ingredients of SR was performed using Traditional Chinese Medicine Systems Pharmacology (TCMSP) Database and Analysis Platform. 36 active compounds were screened by the parameter values of Drug-Likeness (DL), Oral Bioavailability (OB), and Caco-2 permeability (Caco-2), which were based on the drug absorption, distribution, metabolism, and excretion indicators. The UniProt database was used to obtain information on 159 genes associated with active compounds. The main active compounds with antibacterial effects were wogonin, β-sitosterol, baicalein, acacetin and oroxylin-A. Target proteins associated with the antibacterial action were chemokine ligand 2, interleukin-6, tumor necrosis factor, caspase-8,9 and mitogen-activated protein kinase 14. In the future, systems pharmacological analysis of traditional medicine will be able to make it easy to find the important mechanism of action of active substances present in natural medicines and to optimize the efficacy of medicinal effects for combinations of major ingredients to help treat certain diseases.