• Journal of Pharmacopuncture
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• v.19 no.4
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• pp.312-318
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• 2016

Objectives: Bacterial resistant infections have become a global health challenge and threaten the society's health. Thus, an urgent need exists to find ways to combat resistant pathogens. One promising approach to overcoming bacterial resistance is the use of herbal products. Green tea catechins, the major green tea polyphenols, show antimicrobial activity against resistant pathogens. The present study aimed to investigate the effect of catechins, green tea extract, and methylxanthines in combination with gentamicin against standard and clinical isolates of Staphylococcus aureus (S. aureus) and the standard strain of Pseudomonas aeruginosa (P. aeruginosa). Methods: The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) values of different agents against bacterial strains were determined. The interactions of green tea extract, epigallate catechin, epigallocatechin gallate, two types of methylxanthine, caffeine, and theophylline with gentamicin were studied in vitro by using a checkerboard method and calculating the fraction inhibitory concentration index (FICI). Results: The MICs of gentamicin against bacterial strains were in the range of $0.312-320{\mu}g/mL$. The MIC values of both types of catechins were $62.5-250{\mu}g/mL$. Green tea extract showed insufficient antibacterial activity when used alone. Methylxanthines had no intrinsic inhibitory activity against any of the bacterial strains tested. When green tea extract and catechins were combined with gentamicin, the MIC values of gentamicin against the standard strains and a clinical isolate were reduced, and synergistic activities were observed (FICI < 1). A combination of caffeine with gentamicin did not alter the MIC values of gentamicin. Conclusion: The results of the present study revealed that green tea extract and catechins potentiated the antimicrobial action of gentamicin against some clinical isolates of S. aureus and standard P. aeruginosa strains. Therefore, combinations of gentamicin with these natural compounds might be a promising approach to combat microbial resistance.

• YAKHAK HOEJI
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• v.53 no.4
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• pp.194-200
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• 2009

Community-acquired antimicrobial resistant bacteria are an emerging problem whole world-wide. Generally, Hands are main mediator of pathogen transmission as compared with other body parts. So, the purpose of this research was to investigate the microbiological quality and antimicrobial susceptibilities of samples which were collected from the door knob and surface in public- and home-facilities, and also hand. Of total 191 samples, 71 samples (37%) were shown to be of high-level total bacterial count (>$10^8\;CFU/cm^2$). And presence of Staphylococcus and Enteric bacilli was observed in 61 samples (32%) and 76 samples (40%), respectively. Antimicrobial susceptibilities of staphylococcal isolates from the samples were tested for six different antimicrobial agents, which are in wide spread clinical use in Korea, as well as four new antimicrobials, daptomycin, linezolid, quinupristin/dalfopristin and tigecycline. Among staphylococcal isolates, antimicrobial resistance were observed in oxacillin (n=6), mupirocin (n=7), vancomycin (n=1), quinupristin/dalfopristin (n=2) and gentamicin (n=5). Fortunately, all the isolates were susceptible to new antimicrobial such as daptomycin, linezolid and tigecycline. Furthermore 4 Enterococcus faecalis were isolated from four hand samples, and all these isolates exhibited multidrug resistance to four different antimicrobial (oxacillin, quinupristin/dalfopristin, mupirocin, gentamicin). Also, 5 Escherichia coli were isolated from surface in home (n=3), door knob in public facilities (n=1) and hand (n=1). Escherichia coli isolated from hand was high-level resistant to tigecycline ($128{\mu}g$/ml) and gentamicin ($64{\mu}g$/ml).

• Journal of environmental and Sanitary engineering
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• v.23 no.2
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• pp.71-79
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• 2008

We examined 165 unchlorinated natural drinking water samples for the presence of E. coli group resistant to antimicrobial agent and chlorine in nothern Gyeongbuk area in 2007. Among 165 water samples, 21 samples(12.7%) were positive to total coliforms and Six genus, 16 strains of E. coli groups isolated from 16 samples showed resistance against more than one antimicrobial agent such as Ampicillin, Tetracycline and Chloroamphenicol. Among 16 strains, 14 strains resistant to Ampicillin, 9 strains resistant to Tetracycline and one strain resistant to Chloroampenicol. but all 16 strains did not contain any integron gene cassettes, which contribute to the spread of antimicrobial resistance alleles by lateral gene transfer of gene cassettes in a variety of enteric bacteria. The minimal inhibitory concentration(MIC) of 14 strains which showed resistant to Ampicillin was between $12{\mu}g/m{\ell}$ and $32{\mu}g/m{\ell}$, Nine strains resistant to Tetracycline showed between $32{\mu}g/m{\ell}$ and $128{\mu}g/m{\ell}$ and one strain resistant to Chloroampenicol showed $128{\mu}g/m{\ell}$. The chlorine sensitivity of 16 strains isolated from unchlorinated natural water sample did not show any difference among strains by the concentration of initial free chlorine and elapsed time after chlorine treatment. All 16 strains were killed after 1hr. exposure at $0.2mg/m{\ell}$ of free chlorine per liter or 30minutes exposure at $0.4mg/m{\ell}$ of free chlorine per liter.

• Korean Journal of Veterinary Research
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• v.47 no.1
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• pp.67-75
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• 2007

Environmental mastitis has increased particularly in well-managed or low somatic cell countherds that have successfully controled contagious pathogens. Major pathogens of environmental mastitisare Escherichia coli (E. coli) and Streptococcus uberis. The present study was conducted to investigate1,865 quaters of 241 Korean dairy farms from 2001 to 2004. Prevalence of major gram-negative bacteriaisolated from mastitis milk were E. coli (22.7%) and Enterobacter spp. (16.3%) in coliforms and Pseudomoassp. (10.3%) and Serratia spp. (7.9%) in non-coliforms. The results on antibiotic susceptibility by agardifusion test against these pathogens were 86.7% in piperaciliin, 94.6% in cefepime, 85.5% in amikacin,87.7% in gentamicin and so on. In contrast, the susceptibility against ampicillin (41.9%), cephalothin (9.9%),streptomycin (39.9%) and tetracycline (46.7%) appeared to be below 50%. Gram-negative bacteria showed(96.8%). Acording to year, distribution of high $256{\sim}64{\mu}g/ml$ on cephalothin get increased, but the othersare diferent. These findings demonstrate that major gram-negative bacteria were E. coli and Enterobacterspp. isolates, and often encountered the diverse antibiotic resistant patterns.

• Journal of Korean Biological Nursing Science
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• v.23 no.1
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• pp.1-10
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• 2021

Purpose: To verify the anti-microbiotic activity and to develop eco-friendly surface disinfectants using the Opuntia ficus-indica extract. Methods: The stem and fruits of the Opuntia cultivated in Jeju Island were extracted with hot water, 70% EtOH and 100% MeOH, respectively. To examine the antimicrobial activity of the extracts, gram positive bacteria (Bacillus subtilis, Staphylococcus aureus), gram negative bacteria (Escherichia coli, Salmonella typhimurium), yeast (Candida albicans), mold (Aspergillus flavus) and antibiotic resistant bacteria (E. coli, S. aureus) were measured to form a clear zone. Results: The antibacterial activity of the fruit extract was higher than that of the stem extract, and the antibacterial activity of the 100% MeOH (FM) extract and the 70% EtOH (FE) extract of the palm cactus fruit was suitable for the surface disinfectant overall, and clear-zone formed even at relatively low concentrations (250 mg/mL). The FM and FE have antibacterial activity against various bacteria, therefore they can be used as disinfectants. Conclusion: The antimicrobial activity of Opuntia ficus-indica extract from Jeju Island by stem and fruit was determined at relatively low concentrations (250 mg/mL). The Opuntia ficus-indica extract will be useful for surface disinfectants dissolving the patients' bath, oral gargling, and powdered powder in water or ethanol in appropriate concentrations.

• Preventive Nutrition and Food Science
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• v.15 no.1
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• pp.74-77
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• 2010

Antibiotic-resistant Staphylococcus aureus is beginning to pose a social issue. Thus, there is an urgent need for the development of effective anti-staphylococcal agents to eradicate antibiotic-resistant S. aureus in food systems and to treat the pathogen in clinical areas. To address this need, lactic acid bacteria (LAB) from kimchi were screened for the production of anti-staphylococcal bacteriocin. From this screening, a bacteriocin generated by the MK3 strain, which was identified by 16S rRNA gene sequence analysis as Enterococcus faecium, demonstrated antimicrobial activity against an S. aureus strain, and was designated enterocin MK3. Enterocin MK3 also demonstrated activity against other gram-positive bacteria, including several LAB and Listeria monocytogenes, but not gram-negative Escherichia coli. The molecular mass of enterocin MK3 was estimated as approximately 6.5 kDa on an SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) gel.

• Archives of Pharmacal Research
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• v.22 no.1
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• pp.25-29
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• 1999

Psammaplin A, a natural bromotyrosine derivative from an associated form of two sponges (Poecillastra sp. and jaspis sp.) was found to possess the antimicrobial effect on the Gram-positive bacteria, especially on methicillin-resistant Staphylococcus aureus (MRSA). The minimal inhibitory concentration of psammaplin A against twenty one MRSAs ranged from 0.781 to 6.25 ${\mu}g/ml$, which that of ciprofloxacin was 0.391~3.125${\mu}g/ml$. Psammaplin A could not bind to penicillin binding protein, but inhibited the DNA synthesis and the DNA gyrase activity with the respective 50% (DNA synthesis) and 100% (DNA gyrase) inhibitory concentration 2.83 and 100 ${\mu}g/ml$. These results indicate that psammaplin A has a considerable antibacterial activity, although restricted to a somewhat narrow range of bacteria, probably by inhibiting DNA gyrase.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.547-550
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• 2005

Fourteen out of 87 strains of lactic acid bacteria isolated tram Kimchi were found to be resistant against the action of artificial gastric and bile juices. In particular, lactobacilli KM 3, 7, 28, and 37 showed strong resistance and their viable cell counts at the initial stage remained the same even after 3 hours of cultivation in an artificial gastric juice. However, the survival rates of KM 14, 28, and 64 were found to be significantly enhanced in artificial bile juice. Based on the paper disc method, it was evident that isolated lactic acid bacteria showed antibacterial effect against Listeria monocytogenes, Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Vibrio vulnificus, and Salmonella typhimurium. The isolated lactic acid bacteria were identified as Lactobacillus plantarum and Leuconostoc mesenteroides.

• Fashion & Textile Research Journal
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• v.17 no.5
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• pp.838-843
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• 2015

In this study, a cotton knit was dyed with elm bark extract; subsequently, the dyed fabric was measured according to the types of mordants and the preprocessing cationizers used. Additionally, antibiosis against super bacteria was examined. The results follow. First, the color of the dyed cotton knit appeared reddish and yellowish for fabrics treated with non-mordants and mordants. When preprocessing with a cationizer was conducted, the dyeing properties were the best. Second. even when mordants were not used for dyeing, color fastness after washing, sweating, and rubbing was generally good Grade 4 and 5. Color fastness after exposure to sunlight was the best Grade 4 for fabric prepared with ferrous sulfate as the mordant. Third. as for antimicrobial properties, or resistance to super bacteria, the growth of bacteria was suppressed in a meaningful way for fabrics treated with non-mordants and mordants, compared to the control group fabric. The dyeing methods with the most powerful antimicrobial effects were dyeing after preprocessing with a cationizer and preparing fabric with copper sulfate as the mordant. The results stated above show that in case of dyeing with elm bark extract, preprocessing of the cotton knit with a cationizer and dying with copper mordant displayed high levels of antimicrobial properties that were useful for resisting super bacteria. Of these the dyeing properties were the best when preprocessing with a cationizer.

• Microbiology and Biotechnology Letters
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• v.37 no.1
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• pp.80-84
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• 2009

The in vitro antibacterial activities of anti-acne agents prepared from the extracts of natural sources were investigated against several bacteria including antibiotic-susceptible and -resistant Propionibacterium acnes. SD-1 and SD-2 were prepared with different formulations and they showed strong antibacterial activities. The anti-acne agents completely inhibited the growth of the tested strains at the concentration of 0.5%. There was no difference in antibacterial activity between antibiotic-susceptible and -resistant P. acnes. The inhibitory activities of two agents showed time-dependent manner. In S. aureus, time-kill curve demonstrated 2.8- and 3.4-$log_{10}$-unit killing after 8 h with SD-1 and SD-2, respectively. In P. acnes, time-killing curve demonstrated 5.1- and 6.1-$log_{10}$-unit killing after 24 h with SD-1 and SD-2, respectively. SD-2 showed stronger antimicrobial activity than SD-1. From these results, we expect that SD-1 and SD-2 have strong antibacterial activities and have advantages for treating acne.