• Journal of Microbiology
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• v.39 no.2
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• pp.146-148
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• 2001

Lactobacillus crispatus ATCC 33820 and L. gasseri ATCC 33323 were grown in MRS broth (pH 6.5) at 37$^{\circ}C$ for 24 h and the antibacterial activities of cell free culture supernatants were determined by the agar well diffusion method. The culture supernatants were inhibitory to Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Enterococcus faecalis, Pediococcus acidilacticii, and Lactobacillus helveticus. The supernatants did not show any lysozyme activity. Addition of catalase did not affect the antibacterial activities of the supernatants. The antibacterial substances were heat stable (100$^{\circ}C$ for 60 min) and sensitive to proteases.

• Korean Journal of Plant Resources
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• v.21 no.6
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• pp.431-434
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• 2008

Dental caries is the destruction of the enamel of teeth by Streptoccus mutans. S. mutans has been isolated from human dental plaque and is associated with the initial development of enamel lesions. We have studied the antibacterial action of the fruit of Callistemon citrin us against a cariogenic bacterium, S. mutans. From the fruit of C. citrinus, piceatannol (3,3',4',5-tetrahydroxystilbene) was isolated by repeated column chromatography with $SiO_2$ and Sephadex LH-20. Its structure was elucidated by instrumental analysis using 1D-NMR, 2D-NMR and EI-MS. This compound was isolated from the fruit of C. citrin us for the first time. The anticarcinogenic activity of this compound was determined by using agar well-diffusion method and minimal inhibition concentration (MIC).

• Mycobiology
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• v.46 no.4
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• pp.448-451
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• 2018

Fungal perylenequinones have photodynamic activity and are promising photosensitizers for photodynamic therapy (PDT). Here, we investigated the bactericidal and antitumor activities of phleichrome from the fungal perylenequinone family in vitro. Photodynamic bactericidal activity of phleichrome was analyzed by agar-well diffusion method under dark and illuminated conditions. The photodynamic antitumor activity of phleichrome was analyzed in MCF-7, HeLa, SW480, and HepG2 human cancer cell lines using in vitro cytotoxicity assays. Photodynamic bactericidal activities against Gram-negative and Gram-positive bacteria were species-specific. Antitumor activity against all tumor cell lines increased under the illuminated condition. Depending on the results of the analyses, Phleichrome has potential for further drug development related to its antibacterial and antitumor activities.

• International Journal of Oral Biology
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• v.46 no.1
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• pp.45-50
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• 2021

This study evaluated the antimicrobial activity of Endoseal TCS, an mineral trioxide aggregate-based root canal sealer, mixed with water-soluble mangostin derivatives (WsMD) of Garcinia mangostana L. (mangosteen) ethanol extract against Enterococcus faecalis and Staphylococcus aureus. The antibacterial activity of Endoseal TCS mixed with WsMD against three strains of E. faecalis and three strains of S. aureus was performed using agar diffusion test. The data showed that Endoseal TCS mixed with 0.115% WsMD had a zone of inhibition of 0.7 ± 0.2-2.4 ± 0.1 mm. The results suggest that Endoseal TCS mixed with WsMD of Garcinia mangostana L. ethanol extract is useful as a root canal sealer with antibacterial activity against E. faecalis and S. aureus.

• Journal of Pharmacopuncture
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• v.25 no.2
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• pp.101-105
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• 2022

Objectives: This study aims to determine the Fractional Inhibitory Concentration Index (FICI) of combinations of Melastoma malabathricum leaf fraction with ciprofloxacin or gentamicin against pathogenic bacteria, Escherichia coli, Staphylococcus aureus, and Bacillus cereus, isolated from Diabetic Foot Ulcer (DFU) patients. Methods: We tested concentrations of 45%, 55%, 65%, and 75% of gentamicin and ciprofloxacin using dilution and agar diffusion methods. The combination of M. malabathricum leaf extract with these antibiotics was tested in vitro against all three bacteria. Results: The combination of M. malabathricum leaf extract and ciprofloxacin gave a FICI value of 0.5, indicating synergistic antibacterial activity against the test bacteria. Conclusion: The results show that the antibacterial effect of a combination of high doses of the leaf extract with either antibiotic is greater than that of the leaf extract and the antibiotics in single use.

• Microbiology and Biotechnology Letters
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• v.46 no.3
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• pp.225-233
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• 2018

In this exploratory study, eight types of microalgae from different phyla (Chlamydomonas reinhardtii, Chlorella species, Haematococcus pluvialis, Porphyridium purpureum, Porphyridium cruentum, Isochrysis species, Isochrysis galbana, and Pavlova lutheri) were tested for their antibacterial activities against eight target pathogenic bacterial strains. The agar well diffusion method and broth micro dilution assay were conducted to estimate the antibacterial activity. Microalgae cell-free supernatants, exopolysaccharides (EPS), water, and organic solvent extracts were used for inhibition analysis. EPS extracted from P. lutheri showed activity against Bacillus subtilis and Pseudomonas aeruginosa. Inhibition zone diameters of 14-20 mm were recorded on agar plates, while the minimum inhibitory concentrations in the broth micro dilution assay were $0.39-25mg\;ml^{-1}$. During this study, haptophyte microalgae, Isochrysis species, and P. lutheri extracts showed the highest activity against most of the tested pathogenic bacterial strains, while most of the extracts were active against the important foodborne pathogen P. aeruginosa. This study showed promising results regarding important microalgae phyla, which will further aid research related to extracts and exploitation of bioactive metabolic compounds in the food and pharmaceutical industries.

• Korean Journal of Veterinary Service
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• v.23 no.1
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• pp.19-28
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• 2000

There are several main antibacterial susceptibility tests, such as agar dilution method, broth dilution method and disk diffusion technique. Especially, for minimal inhibitory concentration (MIC) test, agar dilution method has been widely used. But that method is so complicated and bothering that it's difficult to treat a large amount of strains. On the other hand, modified broth dilution method(add 1% glucose and 0.018% phenol red as a pH indicator to broth) is fast and easy to perform. Most of all, it can visualize the result by color. The MICs of 22 antibiotics Including penicillins, aminoglycosides, cephalothin, chloramphenicol, lincomycin, ceftiofur, vancomycin and quinolones, erythromycin, colistin. sul-fadimethoxine, trimethoprim for arcanobacterium pyogenes 14 strains, actinobacillus pleuropneu-moniae 41 strains and pasteurella multocida 37 strains, which were collected from porcine during 1996 ∼ 1999, were determined by modified broth dilution method. Actinobacillus pleuropneumoniae was highly susceptible to all kinds of quinolones such as ciprofloxacin, enrofloxacin and norfloxacin and to all aminoglycosides, like gentamicin, apramycin, kanamycin and ampicillin, cephalothin and ceftiofur. But It was quite resistant to solfadimethoxin, colistin and vancomycin. Pasteurella multocida was found to have high susceptibility to ampicillin, cephalothin, chlorampenicol and gentamicin but had mid-degree susceptibility to other aminoglycosides. In addition, it was susceptible to norfloxacin and nalidixic acid, but not to newer fluoroquinolone like ciprofloxacin and enrofloxacin and it was resistant to colistin and kanamycin. Arcanobacterium pyogenes was highly susceptible to most of quinolones such as cipoofloxacin, enrofloxacin and norfloxacin and gentamicin and penicillin G. But it also obtained high resistance against the early quinolone, nalidixic acid and aminoglycosides such as amikacin, apramycin and kanamycin and erythromycin, chlorampenicol, tetracyclin and vancomycin.

• Food Science of Animal Resources
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• v.23 no.1
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• pp.80-85
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• 2003

This study was carried out to investigate antimicrobial and antitumoral activities of Candida kefyr TFP7 isolated from Tibetan fermented milk Strains of TFP1∼10 were isolated from Tibetan fermented milk by agar diffusion method using potato dextrose agar(PDA). Antimicrobial activities were examined against 18 microorganisms of food-related bacteria, yeast, algae, fungi and actinomycetes isolated from soil. Antitumor activities were examined against 9 human tumor cell lines. Strains of TFP2∼10 showed strong antimicrobial activities against Micrococcus luteus ATCC l1880, and strains of TFP6∼10 to actinomycetes, Streptomyces murinus JCM 4333. In antitumor test, all isolated strains(TEP1∼10) showed the growth inhibition of SNU-5 and SW-534 by 60% and 70%, respectively. Among those, the strain TFP7 showed the most antitumor activity, which was 77.5% for SNU-5 and 76.5% for SW-534. The strain was identified as Candida kefyr by use of API 20C AUX kit and scanning electron micrograph.

• Journal of Life Science
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• v.18 no.1
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• pp.69-74
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• 2008

This study carried out to investigate the antimicrobial resistance and biochemical characteristics of Staphylococcus aureus (S. aureus) isolated from reproductive and respiratory tract in Thoroughbred horse. The specimens were collected from equine vaginal mucosa and upper respiratory tract from March to December 2006 using a culture swab in Korea. S. aureus suspected colonies on blood agar plates were selected and identified as standard biochemical tests and PCR (Applied Biosystems, USA). Antimicrobial resistance test of S. aureus isolates was performed with 30 antimicrobial agents (BBL, USA) by using the agar disk diffusion method. S. aureus isolates were isolated 58 (39.2%) strains of 148 samples: wound 64.7% (11/17), genital discharge 37.0% (37/100) and nasal discharge 32.2% (10/31). Almost isolates showed high resistance to spectinomycin, sulfonamides, erythromycin, tetracyelin, ciprofloxacin and penicillin. These results may provide the basic information to establish strategies for treatment and prevention of reproductive and respiratory disease in Thoroughbred horses in Korea.

• Korean Journal of Poultry Science
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• v.7 no.2
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• pp.18-27
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• 1980

Infectious bursal disease, so called Gumboro disease, is found world-wide in areas of intensive poultry farming. The clinical signs of the disease are very indicative, but most infections occur unnoticed due to the age of infection of chicken as well as the degree of virulence of virus affected. Edematous and hemorrhagic lesions in BF at early course of infection and the complete atrophies of BF in later are the most characteristic. The infection is considered highly contagious by direct contact, by fecal material and by contaminated feed and water. The virus is also highly resistant in environment and belongs to Diploma virus with size of 55 to 60nm of Ribovirus group. IBDV grows in embryos, embryonic cells and BF of susceptible chickens. Immune-diffusion using agar gel is the method of a choice to determine IBDV infection in chickens. Maternal immunity is very effective in protecting chickens of critical age when IBDV infection severely damages the function of BF. Immunosuppressive effect of IBDV causes more production losses than direct effects of clinical disease of IBD. Inclusion body hepatitis, infectious anemia and gangrenous dermatitis syndrome are the disease associated with the immunosuppressive condition of chickens.