• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.1128-1131
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• 1999

Antioxidative and antimicrobial effects of the extracts of Castanea crenata leaf tea, steamed tea and semi-fermented tea were investigated. Antioxidative effects were by measuring the 1,1-diphenyl-2-picrylhydrazyl(DPPH)-radical scavening activity of the extracts. The effects were stronger than that of synthetic antioxidant such as BHT at the same concentration. The $SC_{50}$ value (50% radical scavening effects of $1{\times}10^{-4}$ M DPPH) of steamed tea, semi-fermented tea and BHT were 53.3 ${\mu}g/mL$, 49.9 ${\mu}g/mL$ and 101.0 ${\mu}g/mL$, respectively. The antimicrobial effects of methanol extracts (8 mg, 20 mg) of 0.2 g and 0.5 g. eq. of Castanea crenata leaf tea were stronger than those of 0.65 mg of benzoic acid, against gram(+) bacteria such as S. aureus, S. epidermidis, M. luteus, L. mesenteroides and B. subtilis and gram(-) bacteria such as E. coli, S. typhimurium, and P. aeruginosa.

• Journal of Food Hygiene and Safety
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• v.31 no.3
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• pp.201-209
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• 2016

Many atmospheric pollutants including chemical agents, house dust, and microorganisms cause building-related illnesses through respiration in humans. This study was conducted to analyze the profiles of microbial pollutants in air purifiers used in home, office and playschool. Dominant eleven species of microorganisms were isolated and identified in environmental air and air purifiers. Among them, Staphylococcus sp., Micrococcus sp. and Bacillus sp. are the most dominant species. By phylogenetic analysis of the 16S rRNA gene, the dominant bacteria were identified as Staphylococcus epidermidis, Micrococcus luteus and Bacillus epidermidis, respectively. It has been known that these bacterial species are closely related with food spoilage and human infectious disease. Thus, these results indicate that microbial pathogens related with human illnesses through respiration will be contaminated in air purifiers and also need to develop a method to control those of pathogens for human health.

• Journal of Microbiology and Biotechnology
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• v.18 no.1
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• pp.74-79
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• 2008

The aim of this study was to analyze the chemical composition of 14 kinds of citrus oils and to test their biological activities. Citrus essential oils were obtained by steam distillation from immature fruits collected from Jeju Island and were analyzed using gas chromatograph (GC)-flame ionization detectors (FID) and GC-MS. Limonene (55.4% to 91.7%), myrcene (2.1% to 32.1%), ${\alpha}$-pinene (0.6% to 1.6%) and linalool (0.4% to 6.9%) were the major components in most citrus species. To evaluate in vitro antibacterial activity, all essential oils were tested against Propionibacterium acnes and Staphylococcus epidermidis. Nine out of fourteen citrus oils exhibited antibacterial activity against P. acnes, but not against S. epidermidis. The effects of the citrus oils on DPPH radical scavenging, superoxide radical anion scavenging, nitric oxide radical, and cytotoxicity were also assessed. Three essential citrus oils, Joadeung, Dongjunggyul, and Bujiwha, exhibited potent inhibitory effects on nitric oxide production. Two essential oils, Dongjunggyul and Joadeung, showed potent free radical scavenging activities in the DPPH assay. For future applications in cosmetic products, we also performed MTT assays in a human dermal fibroblast cell line. The majority of the essential oils showed no cytotoxicity. The results indicate that citrus essential oils can be useful natural agents for cosmetic application.

• Food Science of Animal Resources
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• v.43 no.5
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• pp.792-804
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• 2023

Non-aureus staphylococci (NAS), particularly antimicrobial-resistant NAS, have a substantial impact on human and animal health. In the current study, we investigated (1) the species profiles of NAS isolates collected from healthy broilers, farm environments, and farm workers in Korea, (2) the occurrence of antimicrobial-resistant NAS isolates, especially methicillin resistance, and (3) the genetic factors involved in the methicillin and fluoroquinolone resistance. In total, 216 NAS isolates of 16 different species were collected from healthy broilers (n=178), broiler farm environments (n=18), and farm workers (n=20) of 20 different broiler farms. The two most dominant broiler-associated NAS species were Staphylococcus agnetis (23.6%) and Staphylococcus xylosus (22.9%). Six NAS isolates were mecA-positive carrying staphylococcal cassette chromosome mec (SCCmec) II (n=1), SCCmec IV (n=1), SCCmec V (n=2), or nontypeable SCCmec element (n=2). While two mecA-positive Staphylococcus epidermidis isolates from farm workers had SCCmec II and IV, a mecA-positive S. epidermidis isolate from broiler and a Staphylococcus haemolyticus isolate farm environment carried SCCmec V. The occurrence of multidrug resistance was observed in 48.1% (104/216 isolates) of NAS isolates with high resistance rates to β-lactams (>40%) and fusidic acid (59.7%). Fluoroquinolone resistance was confirmed in 59 NAS isolates (27.3%), and diverse mutations in the quinolone resistance determining regions of gyrA, gyrB, parC, and parE were identified. These findings suggest that NAS in broiler farms may have a potential role in the acquisition, amplification, and transmission of antimicrobial resistance.

• Journal of Life Science
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• v.20 no.7
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• pp.1143-1150
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• 2010

The antibacterial activity of methanol extracts from 70 kinds of oriental medicinal herbs on four strains of Staphylococcus aureus and S. epidermidis was investigated. The results showed that C. japonica, C. sappan, R. javanica, R. tanguticum, and S. miltiorrhiza had an antibacterial activity on all the strains used. Among these, C. japonica and R. javanica, which showed excellent antibacterial activity, were extracted with water, ethanol, methanol, and ethyl acetate for further study of antibacterial activities. The results showed that the boiled water extract of C. japonica had the best antibacterial activity. Assuming that the antibacterial activity of C. japonica originated from berberine, which has been reported many times, the berberine content of the boiled water extract of C. japonica was analyzed and the result was 13.88%. To compare the antibacterial activity of berberine with that of other antibiotics, berberine chloride and three other kinds of antibiotics were investigated, which showed that berberine chloride had an antibacterial activity on KCCM 35494 S. epidermidis only when the concentration was higher than 600 mg/l, and it did not show antibacterial activity in the other strains. Based on these results, it was concluded that the antibacterial activity of the boiled water extract of C. japonica on the strains used in this study originated from high concentration of berberine or substances other than berberine. Therefore, identification of the substance will be necessary.

• Journal of Chest Surgery
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• v.28 no.4
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• pp.360-364
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• 1995

Between January 1984 and January 1994, 13 patients developed mediastinitis after cardiac operations. There were 7 women and 6 men with a mean age of 24.2 years[range 0.7 - 61 . Initial operation included 7 valve replacements and 6 congenital cardiac repairs. The duration between initial operation and diagnosis was 13.5 days[range 4-57 . Organisms cultured from debridement material included S.aurus[n=9 , S.epidermidis[n=3 and Enterobacter[n=1 . Fever was the most frequent complaint and purulent drainage was noticed in 9 patients[69% . Seven patients were treated with radical debridement followed by closed irrigation. In other 6 patients, the wounds were managed by debridement, open granulation and delayed wound closure. Two hospital deaths [15.4% following open granulation method, resulted from sepsis. The 11 survivors were followed-up for 1-120 months, averaging 42 months and had healed wounds. One late death occurred due to massive hemorrhage.

• Korean Journal of Veterinary Research
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• v.23 no.2
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• pp.165-172
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• 1983

The distribution of slide coagulase-negative staphylococci isolated from bovine mastitic milk samples was investigated mainly according to Kloos and Schleifer's classification scheme, and toxigenic and enzymatic characteristics of these strains were also examined. One-hundred-and-twenty-one strains of coagulase-negative staphylococci isolated were classified into 8 species. Of these species, Staphylococcus epidermidis, Staph. xylosus, Staph. haemolyticus and Staph. simulans were more frequently found in bovine mastitic milk samples, and toxin and enzyme production of these species were observed in relatively high frequency. Staph. hyicus subsp. hyicus was isolated from the 4 quarters with clinical mastitis included in this investigation. By the use of Baird-Parker and Pelzer's classification system, 44.6% and 18.2% of the strains could not be classified in any subgroup, respectively.

• Journal of the Korean Vacuum Society
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• v.7 no.s1
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• pp.44-49
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• 1998

The antimicrobial effects of HAp and Ag-HAp was observed using periprosthetic infection bacteria such as Pseudomonas Aeruginosa, Staphylococcus Epidermidis, Escherichia coli (DH5$\alpha$). Ag-HAp showed good antimicrobial effects. TEM study of E. coli with and without Ag treatment in HAp was experimented in order to find the mechanism of Ag in antimicrobial effects. It was observed that the shape of Ag-treated E. coli was changed, the cells walls became inhomogeneous. The vaculoes at cytoplasm formed into E. coli and finally it was discovered by EDAX that there were many dark granules which contain the Ag element inside the cells.

• Journal of the Korean Vacuum Society
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• v.6 no.S1
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• pp.27-33
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• 1997

Recently ion beam assistant deposition (IBAD) was successfully used to produce a dense ultra-adherent and pinhole-free hydroxyapatite (HAp) layer on alumina substrate. After that the HAp-coated alumina was immersed in 20ppm and 100ppm $AgNO_3$ solution at room temperature for 48 hours to carry out the ions exchange between $Ag^+\;and\;Ca^+$ in HAp. The obvious antimicrobial effect against E.Coli, P. Aeruginosa and S. Epidermidis was observed in the samples treated with 20ppm $AgNO_3$ Solution, In contrast to this the untreated samples did not show any bactericidal effect. Scanning electron microscope(SEM) study showed that Ag homogeneously distributed on the surface. X-ray diffraction (XRD) demonstrated that the surface structure in the samples without Ag was HAp whereas with Ag is HAp and AgCaP. It appears that silver ions exchange with calcium ions in HAp does not cause significant changes in the structure of HAp coatings.

• Journal of Life Science
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• v.22 no.10
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• pp.1344-1351
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• 2012

We studied the physical, chemical, biological, and antimicrobial effects of eight types of essential oils used in the cosmetics industry: lavender, tea tree, rosemary, juniper berry, Chamaecyparis obtusa, cypress, cedar wood, and pine. Lavender oil had a linalyl acetate (an ester chemical compound) content of 48% and radical scavenging activity of 22.36% at 5,000 ppm. Tea tree oil had radical scavenging activity of 43.94% at 5,000 ppm and antimicrobial activity against S. aureus, S. epidermidis, S. mutans, and C. albicans in each 6, 3.5, 6.5, and 5 mm, respectively. Chamaecyparis obtusa oil had the highest acidity (pH 2.64) compared with the other oils, and sesquiterpene compounds were found to have 19.20%. Cedar wood oil had the highest specific gravity and refractive index compared to the other oils and had a sesquiterpene content of 99.73%. The radical scavenging activity of cedar wood essential oil exceeded 39.68% at 5,000 ppm. The clear zone, indicating antimicrobial activity against P. acnes, P. ovale, and C. albicans, was 3.5, 6, and 6 mm, respectively, at a concentration of 1% cedar wood oil. Results showed that with a high sesquiterpene content, the antioxidant effect was generally, but not always, high, suggesting that this is determined according to composition of the compound rather than presence of each antioxidant. The results indicate that antimicrobial activity is determined by the existence of each antimicrobial ingredient rather than terpene composition.