• 미생물학회지
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• 제38권2호
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• pp.57-61
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• 2002

전라남도 장흥군 인근 해안에서 채집한 불가사리(Asterias amurensis)를 대상으로 불가사리의 장내에 분포하는 종속영양세균의 균체수를 측정하였고, 분리동정된 균주들을 대상으로 탄소원 이용 특성을 조사하였다. 불가사리의 장내에 분포하는 종속영양세균의 균체수는8.65$\pm$0.65 $\times$$10^3$ cfu . g$^{-1}$이 였으며, 분리 동정된 24균주(그람음성균 11균주, 그람양성균이 13균주)중에서 Vibrio속,Staphylococcus속, Corynebacterium속이 높게 나타났다. 불가사리 장내에서 분리 동정된 세균들은 그람양성의 간균이 높은 비율을차지하였고, catalase와 oxidase의 활성은 각각 54.2%,20.8%로 나타났다. 그람음성균의 경우, 탄소원으로 glucose의 이용률이 가장 높았고, 그 다음으로 sucrose, mannose, maltose,그리고 trehalose의 순으로 높은 이용률을 나타냈으며, adipate, phenol acetate는 이용하지 못하였다. 그람양성균의 경우, glucose가 가장 높은 이용률을 나타냈고, 그 다음은 fructose, trehalose, maltose 순으로 높은 이용률을 보였다.

• Asian-Australasian Journal of Animal Sciences
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• 제4권3호
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• pp.281-284
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• 1991

Combination effects of sulfamethoxazole (SMX) and trimethoprim (TMP) against nine gram positive bacterial strains and 43 gram negative bacterial strains which included 40 strains of animal intestinal bacteria were studied in vitro. Minimum inhibitory concentrations (MICs) of SMX and TMP alone and 20:1 (SMX : TMP) mixture (ST) were investigated by the method recommended by Ad Hoc Committee of the Japan Society of Chemotherapy for the Evaluation of Sensitivity Testing Methods for Sulfamethoxazole and Trimethoprim. MICs of ST were more potentiated than those of SMX alone in 8 of 9 gram positive strains and 40 of 43 gram negative strains. Especially, 38 strains of 40 intestinal bacteria showed significant susceptibility to ST as compared to SMX. These results suggest a strong synergistic activity of ST mixture against animal intestinal bacteria, The activity was considered to be comparable to those of other current antibiotics.

• Journal of Microbiology and Biotechnology
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• 제24권6호
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• pp.803-811
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• 2014

Concerns over drug-resistant bacteria have stimulated interest in developing alternative methods to control bacterial infections. Endolysin, a phage-encoded enzyme that breaks down bacterial peptidoglycan at the terminal stage of the phage reproduction cycle, is reported to be effective for the control of bacterial pathogenic bacteria. Bioinformatic analysis of the SPN9CC bacteriophage genome revealed a gene that encodes an endolysin with a domain structure similar to those of the endolysins produced by the P1 and P22 coliphages. The SPN9CC endolysin was purified with a C-terminal oligo-histidine tag. The endolysin was relatively stable and active over a broad temperature range (from $24^{\circ}C$ to $65^{\circ}C$). It showed maximal activity at $50^{\circ}C$, and its optimum pH range was from pH 7.5 to 8.5. The SPN9CC endolysin showed antimicrobial activity against only gram-negative bacteria and functioned by cutting the glycosidic bond of peptidoglycan. Interestingly, the SPN9CC endolysin could lyse intact gram-negative bacteria in the absence of EDTA as an outer membrane permeabilizer. The exogenous lytic activity of the SPN9CC endolysin makes it a potential therapeutic agent against gram-negative bacteria.

• 한국임상수의학회지
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• 제28권4호
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• pp.348-351
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• 2011

The purpose of this study was to determine the distribution of gram-negative bacteria isolated from companion animals with sepsis, and to investigate the antimicrobial susceptibility patterns of the isolates. Bacterial pathogens were isolated from specimens of dogs and cats submitted to National Veterinary Research and Quarantine Service between 2008 and 2009. A total of 44 gram-negative pathogens were isolated from necropsied organs. The most common isolates were E. coli (n = 33), K. pneumoniae (n = 4) and B. bronchiseptica (n = 4). Most of gram-negative isolates were susceptible to ceftiofur (68.2%), colistin (84.1%), florfenicol (84.1%) and spectinomycin (61.4%). Most of those were resistant to ampicillin (77.3%), erythromycin (86.4%), flumequine (65.9%), lincomycin (97.7%), oxytetracycline (61.4%), penicillin (100%), streptomycin (63.6%), spiramycin (97.7%), sulfamethoxazole (90.9%), tylosin (97.7%) and tiamulin (100%). In conclusion, colistin and florfenicol could be useful against sepsis due to gram-negative bacteria.

• Journal of Dairy Science and Biotechnology
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• 제39권3호
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• pp.121-127
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• 2021

Yogurt is produced by bacterial fermentation of milk and contains lactic acid bacteria (LAB), which produce various metabolites such as organic acid, hydrogen peroxide, and bacteriocin. This study aimed to investigate cell-free supernatants (CFS) of LAB isolated from Tibetan yogurt. CFS (TY1, TY2, TY3, TY4, TY5, TY6, and TY7) from selected strains of LAB were co-incubated with four different foodborne pathogenic bacteria, namely E. coli O157:H7, Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus. Inhibition of foodborne pathogenic bacterial growth was not affected in the presence of CFS (pH 6.5). In contrast, CFS without neutralization completely inhibited the growth of the bacteria. Furthermore, when the concentration of CFS (without neutralization) was changed to 1:4 and 1:8, a difference in inhibition was observed between Gram-positive and Gram-negative bacteria. CFS more effectively inhibited the growth of Gram-negative E. coli O157:H7 and S. Typhimurium than Gram-positive L. monocytogenes and S. aureus. These results suggest that organic acids in LAB may inhibit the growth of foodborne pathogenic bacteria, particularly Gram-negative bacteria.

• 생약학회지
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• 제23권4호
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• pp.240-247
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• 1992

Impatiens balsamina Linne(Balsaminaceae) known as 'BONG SUN HWA' in Korea and has been used for the treatment of scrofulosis, carbunculus and dysenteria etc. Bioassay-guided fractionation of MeOH extract from the whole plants of Impatiens balsamina has afforded a simple naphthoquinone derivative, 2-methoxy-1,4-naphthoquinone. The structure of this compound was established by spectroscopic methods. This compound possessed strong antifungal activity against Candida albicans, AspergiIlus niger, Crytococcus neoformans and Epidermophyton floccusum. The activity of 2-methoxy-1,4-naphthoquinone on E. floccusum $(MIC{\;}:{\;}5.0{\;}{\mu}g/ml)$ was the same potency as that of nystatin. It showed also strong antibacterial activity against gram-positive bacteria Bacillus subtilis as well as gram-negative bacteria Salmonella typhimurium. Although the activity of this compound on gram-negative bacteria was lower than that of gram-positive bacteria.

• Journal of Microbiology and Biotechnology
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• 제14권2호
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• pp.317-323
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• 2004

This study was performed to investigate the antimicrobial effects of hetero-chitosans and their oligosaccharides against three Gram-negative bacteria and five Gram-positive bacteria. Nine classes of hetero-chitosan oligosaccharides consisted of partially deacetylated chitosans; 90％, 75％, and 50％ deacetylated chitosans. Based on molecular weight, they were prepared using an ultrafiltration membrane reactor system. Seventy-five percent deacetylated chitosan showed the highest antimicrobial acitivity as compared with the 90％ and 50％ deacetylated chitosan, and the activity was dependent on their molecular weights. It was apparent that the growth of Gram-negative bacteria is less inhibited in the presence of the heterochitosans and their oligosaccharides than Gram-positive bacteria. These results revealed that the antimicrobial effects of hetero-chitosans and their oligosaccharides depend on the degree of deacetylation, and their molecular weights.

• 대한한방내과학회지
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• 제26권3호
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• pp.521-532
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• 2005

Objectives & Methods : In order to evaluate the in vitro synergic effects or Eunkyo-san which is a traditional poly-herbal formula that has been used in the treatment of respiratory diseases in oriental medicine, and quinolone antibiotics, rufloxacin (RUFX) and iprofloxacin(CPFX), experimentation was designed to determine minimal inhibitory concentration(MIC), $MIC_{50}\;and\;MIC_{90}$ of single use of quinolones and concomitant treatment with Eunkyo-san against 5 strains of aerobic gram negative bacteria, Escherichia coli, Klebsiella peumoniae, Hemophilus influenzae, Citrobacter freundii and Pseudomonas aeruginosae. Result : In the case of aerobic gram negative bacteria, the MIC, $MIC_{50}\;and\;MIC_{90}$ against Klebsiella peumoniae and Citrobacter freundii significantly decreased in concomitant-treated groups with Eunkyo-san compared to those of single-treated groups of RUFX and CPFX, respectively. However, no significant changes were demonstrated against Echerichia coli, Hemophilus influenzae and Pseudomonas aeruginosae. Conclusion : According to these results, concomitant use of Eunkyo-san against some strains of aerobic gram-negative bacteria dramatically increases in vitro antibacterial activity of RUFX and CPFX, and the increase and selectivity of antibacterial activities against these strains is attributable to Eunkyo-san, and not RUFX or CPFX activity.

• 동의생리병리학회지
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• 제19권3호
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• pp.684-689
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• 2005

In order to evaluate the in vitro synergic effect of Mahwangyounpae-tang which was a traditional poly-herbal formula has been used in the treatment of respiratory diseases in oriental medicine, and quinolone antibiotics, ciprofloxacin (CPFX), the minimal inhibitory concentration (MIC), $MIC_{50}$ and MIC90 of single use of quinolones and concomitant treatment with Mahwangyounpae-tang against 5 strains of aerobic gram negative bacteria, Escherichia coli, Klebsiella peumoniae, Hemophilus influenzae, Citrobacter freundii and Pseudomonas aeruginosae. The obtained results were as follows : In the case of aerobic gram negative bacteria, the MIC, $MIC_{50}$ and $MIC_{90}$ against Klebsiella peumoniae and Pseudomonas aeruginosae was significantly decreased in concomitant treated groups with Mahwangyounpae-tang compared to those of single treated groups of CPFX, respectively. However, no significant changes were demonstrated against Echerichia coli, Hemophilus influenzae and Citrobacter freundii. According to these results, it is considered as the in vitro antibacterial activity of CPFX was dramatically increased by concomitant use of Mahwangyounpae-tang against some strains of aerobic gram negative bacteria and the increase and selectivity of antibacterial activities against strains were chosen by the selectivity of Mahwangyounpae-tang not CPFX activity.

• 대한족부족관절학회지
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• 제25권2호
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• pp.100-107
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• 2021

Purpose: The present study aimed to develop guidelines regarding initial choice of antibiotics for diabetic foot ulcers (DFU) by investigating bacterial isolates. Materials and Methods: This study included 223 DFU patients that visited a single tertiary hospital and underwent bacterial culture between January 2016 and February 2020. The study was conducted in two parts: 1) to compare bacterial isolates and wound healing according to comorbidities such as chronic kidney disease (CKD) and peripheral artery disease (PAD), and 2) to compare bacterial isolates according to wound depth using the Wagner classification. Results: Of the 223 patients, 43 had CKD (group A), 56 had PAD (group B), 30 had CKD and PAD (group C), and 94 had none of these comorbidities (group D). The isolation rate for multidrug-resistant gram-negative bacteria (MRGNB) and gram-negative to gram-positive bacteria ratio were highest in group C (p=0.018, p=0.038), and the proportion that achieved wound healing was lowest in group C (p<0.001). In the second part of the study, subjects were classified into 5 grades by wound depth using the Wagner classification; 13 grade I, 62 grade II, 60 grade III, 70 grade IV, and 17 grade V. No significant difference was observed between these grades in terms of isolation rates or gram-negative to gram-positive bacteria ratios. Conclusion: This study suggests antibiotics that cover gram-negative bacteria including MRGNB produces better results in the presence of CKD and PAD and that initial antibiotic choice should be based on the presence of CKD and PAD rather than wound depth.