• Particle and aerosol research
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• v.5 no.3
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• pp.111-122
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• 2009

This paper reviews about synthesis of nanoparticles by spark discharge and applications. A method of catalytic activation with Pd and Pt aerosol nanoparticles produced by spark discharge was introduced. After annealing, the catalytically activated substrate placed into a solution for electroless silver deposition. The silver was then formed only on the activated regions of the substrate. Silver line patterns having a width of $18{\mu}m$ and a height of $1{\mu}m$ were created with the ability to be effectively reproduced. Antimicrobial nanoparticles such as silver were used for removal of bioaerosols. Silver nanoparticles deposited air filters such as ACF filters were evaluated by antimicrobial test.

• The Plant Pathology Journal
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• v.26 no.1
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• pp.57-62
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• 2010

Low-molecular-weight secondary metabolites from plants play an important role in reproductive processes and in the defense against environmental stresses or pathogens. In the present study, we isolated various volatiles and phenolic compounds from white Rosa rugosa flowers, and evaluated the pharmaceutical activities of these natural products in addition to their ability to increase survival in response to environmental stress and pathogen invasion. The DPPH and hydroxyl radical-mediated oxidation assay revealed that the white rose flower extract (WRFE) strongly scavenged free radicals in a dose dependent manner. Moreover, WRFE inhibited the growth of E. coli and fatally attacked those cells at higher concentration (>0.5 mg/mL). FITC-conjugated Annexin V stain provided further evidence that WRFE had strong antimicrobial activity, which may have resulted from a cooperative synergism between volatiles (e.g. 1-butanol, dodecyl acrylate and cyclododecane) and phenolic compounds (e.g. gallic acid) retained in WRFE. In conclusion, secondary metabolites from white rose flower hold promise as a potential natural source for antimicrobial and non-chemical based antioxidant agents.

• Microbiology and Biotechnology Letters
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• v.27 no.2
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• pp.172-178
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• 1999

In this study, we tested possibility of replacing nitrite salts, which were always added during the meat product processing, with the metabolites produced by antimicrobial and red pigment producing Monascus strains. We have already shown that Monascus No. 116 strain has the highest antimicrobial activity among the strains isolated from Ang-Khak. Monascus isolate No. 229 was chosen due to its outstanding red pigment producing ability. The red pigment production by No. 229 was highest in the medium containing 8% sucrose, 2% yeast extract, 0.1% K2HPO4, 0.5% MgSO4. Optimum pH and temperature for the red pigment production were pH 6.2 and 3$0^{\circ}C$, was found in spot or Rf value 0.54 on TLC plate using ethyl acetate-acetone-water (4:4:1, v/v/v) as development solvent system. Isolate No. 116 and No. 229 were cultured in a optimal condition for the antimicrobial activity and red pigmentation. The culture concentrates were applied in situ to the production of instantly processed ham. Mixed application of 89 ppm Na-nitrite and 300 ppm of culture broth concentrate of Monascus isolate No. 116 and 500 ppm of red color produced by Monascus isolate No. 229 showed similar results with the single application of 94 ppm Na-nitrite. These results confirmed that the antimicrobial activity and red pigment of Monascus strains might be valuable to replace Na-nitrite salt in meat processing.

• Korean journal of food and cookery science
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• v.23 no.1 s.97
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• pp.33-40
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• 2007

This study investigated the antioxidative and antimicrobial activities of nutmeg (water, ethanol extract and essential oil). The total phenol contents of water, ethanol extract and essential oil were 3.4%, 16.9%, and 3.2%, respectively. Hydrogen donating abilities of water, ethanol extract and essential oil at 1,000 ppm were 4.9%, 41.8% and 6.8%, respectively. The antioxidative activities in linoleic acid substrates were in the order of BHT > ethanol > extract > ${\alpha}$-tocopherol > essential oil > water extract. The antioxidative activities in linoleic acid emulsion substrates were in the order of BHT > water extract > essential oil > ethanol extract > ${\alpha}$-tocopherol. In antimicrobial activity, ethanol extract showed growth inhibition effect against Micrococcus luteus, Bacillus cereus and Salmonella enteritidis, and the essential oil showed growth inhibition effect against Micrococcus luteus. However, no antimicrobial activity of water extract was observed. The nitrite-scavenging abilities of water, ethanol extract and essential oil at 1,000 ppm were 4.5%, 28.8% and 98.8%, respectively, and the ACE inhibitory activities were 0.2%, 11.0% and 10.0%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.5
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• pp.648-654
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• 2010

This study investigated the antioxidant activities and antimicrobial effects of MeOH extracts from some spices. The total flavonoid contents of MeOH extracts from ginger, garlic, onion, Chinese pepper (Zanthoxylum schinifolium) and black pepper (Piper nigrum) were 20.3%, 10.0%, 4.3%, 6.6% and 12.8%, while the total phenol contents were 19.3%, 1.0%, 0.5%, 3.4% and 7.9%, respectively. The order of the nitrite-scavenging abilities of spice extracts were ginger> black pepper> Chinese pepper> garlic> onion (p<0.05). MeOH extract from ginger showed antimicrobial activity to Bacillus cereus, and garlic extract showed strong antimicrobial activity to Salmonella enteritidis. However, onion extract did not show any antimicrobial activity. The electron donating ability of MeOH extract from ginger was markedly higher than those of garlic, Chinese pepper, black pepper and onion extracts. Antioxidative activities in linoleic acid substrates were in order of BHT> ginger> Chinese pepper> black pepper> garlic> $\alpha$-tocopherol> onion. Antioxidative activities in linoleic acid emulsion substrates were in order of BHT> $\alpha$-tocopherol> ginger> black pepper> Chinese pepper> garlic> onion.

• Food Science and Preservation
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• v.18 no.5
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• pp.764-772
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• 2011

Hot-water and 70%-ethanol Smilax china leaf extracts were prepared, and their total polyphenol and flavonoid contents, DPPH-radical-scavenging ability, nitrite-scavenging ability, and antimicrobial activity were determined. The total polyphenol contents of the hot-water and ethanol extract were $5.433{\pm}0.171$ and $13.060{\pm}0.110mg/g$, respectively; their flavonoid contents were $1.599{\pm}0.017$ and $3.005{\pm}0.084mg/g$; their DPPH-radical-scavenging abilities, assayed at 1.0 mg/mL, were 33.6 and 92.3%; and their nitrite-scavenging abilities, assayed at 0.1-2.0 mg/mL, were 37.9-61.6 and 38.4-77.8%. The 70%-ethanol extract showed higher antimicrobial activity than the hot-water extract. The antimicrobial activities were high in Bacillus cereus, Vibrio parahaemolyticus, Salmonella typhymurium, and Staphylococcus aureus, in that order. The antimicrobial substances in the two extracts were maintained after heating at $65-125^{\circ}C$ for 30 min.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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• pp.774-781
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• 2015

The objective of the present study was to determine the total phenol and flavonoid contents and to evaluate the antioxidant potential, of different solvent extracts (ethyl acetate, n-butanol, chloroform, and water) from Robus idaeus in various radical scavenging models (DPPH activity, superoxide dismutase (SOD) activity, reducing power, and nitrite scavenging activity), along with their antimicrobial potential. Measurement of total phenol and flavonoid content of the ethyl acetate extract of R. idaeus was found to be significantly higher than those of the other extracts. The ethyl acetate extract (at a concentration of $1,000{\mu}g/mL$) showed significantly higher reducing power and DPPH radical scavenging activity as compared to the other extracts. Results were dose-dependent. Moreover, the ethyl acetate extract of R. idaeus ($1,000{\mu}g/mL$) showed potent antioxidant efficacy ($85.5{\pm}1.18%$) as evidenced by nitrite scavenging ability at pH 1.2. All solvent extracts of R. idaeus showed lower SOD-like activity (13.72~20.54%). In addition, the antimicrobial activity of all solvent extracts except water extract showed strong inhibition (inhibitory zones in mm) of Staphylococcus aureus ($19.40{\pm}1.00mm$) and Bacillus cereus ($20.50{\pm}0.21mm$) growth. In particular, ethyl acetate extracts (100 mg/mL) showed antimicrobial activity comparable to that of tetracycline (0.01 mg/mL), which was used as a positive control. The results of this study indicate that the ethyl acetate extract of R. idaeus is a natural antioxidant and antimicrobial, with enriched phenols and flavonoids concentration, that has potential in the development of health-enhancing food products.

• Journal of Microbiology and Biotechnology
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• v.28 no.4
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• pp.510-519
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• 2018

Synbiotics are a combination of probiotics and prebiotics, which lead to synergistic benefits in host welfare. Probiotics have been used as an alternative to antibiotics. Among the probiotics, Pediococcus acidilactici (PA) has shown excellent antimicrobial activity against Salmonella Gallinarum (SG) as a major poultry pathogen and has improved the production performances of animals. Inulin is widely used as a prebiotic for the improvement of animal health and growth. The main aim of this study was to investigate the antimicrobial activity of inulin nanoparticle (IN)-internalized PA encapsulated into alginate/chitosan/alginate (ACA) microcapsules (MCs) for future in vivo application. The prepared phthalyl INs (PINs) were characterized by DLS and FE-SEM. The contents of phthal groups in the PINs were estimated by $^1H-NMR$ measurement as 25.1 mol.-%. The sizes of the PINs measured by DLS were approximately 203 nm. Internalization into PA was confirmed by confocal microscopy and flow cytometry. The antimicrobial activity of PIN-internalized probiotics encapsulated into ACA MCs was measured by coculture antimicrobial assays on SG. PIN-internalized probiotics had a higher antimicrobial ability than that of ACA MCs loaded with PA/inulin or PA. Interestingly, when PINs were treated with PA and encapsulated into ACA MCs, as a natural antimicrobial peptide, pediocin was produced much more in the culture medium compared with other groups with inulin-loaded ACA MCs and PA encapsulated into ACA MCs.

• Food Science and Preservation
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• v.8 no.4
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• pp.475-480
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• 2001

Yields of bamboo extracts were 1.0∼1.5% in stalks and 3.1∼3.2% (w/w) in leaves. Electron donating ability of extracts from stalks was 62% in Maengjongjuk, 55% in Somdae and 52% in Wangdae, while that of leaf extracts showed very low level. On the contrary, nitrite-scavenging activity was higher in leaf extracts than stalk extracts, and the activity was 63, 57 and 55% in leaf extracts of Maengjongjuk, Wangdae and Somdae, respectively. Antimicrobial activity was examined against 7 major strains which cause food poisoning, and extracts of bamboo stalks showed somewhat activity, while leaf extracts showed merely or no activity according to strains. But all extracts showed relatively strong antimicrobial activity against Staphylococcus aureus and Vibrio parahaemolyticus, and extracts of Somdae stalks and Maengjongjuk leaves showed antimicrobial antimicrobial activity against those strains on 100${\mu}\ell$/disc concentrate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.967-972
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• 2006

The antioxidative and antimicrobial activities were determined on the mushroom (Sarcodon aspratus) extracts in order to find out new food functional components. The antioxidative activities of water and ethanol extracts from the Sarcodon aspratus were measured by peroxide values (POV), electron-donating ability (EDA) using 1,1-diphenyl-2-picryl hydroxyl (DPPH), nitrite-scavenging ability and superoxide dismutase-like activity (SODA) by pyrogallol. The antioxidative activity of the ethanol extract measured by POV was higher than those of the water extract, BHT, and ${\alpha}-tocopherol$. The EDA of the water extract and ethanol extract using DPPH showed the highest values of 76.94% and 73.06%, respectively. The nitrite-scavenging abilities (pH 1.2, 1,000 ppm) of the water and ethanol extracts were 72.61% and 62.69%, respectively, and the nitrite-scavenging ability of the water extract was higher than that of the ethanol extract in all pH values. The SODA of the ethanol extract was higher than that of the water extract. The Sarcodon aspratus extracts had antimicrobial effects on Listeria monocytogenes and Staphylococcus aureus.