• Nutrition Research and Practice
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• v.1 no.4
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• pp.273-278
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• 2007

The objective of this study was to evaluate the inhibitory activity of natural products, against growth of Escherichia coli (ATCC 25922) and Salmonella typhimurium (KCCM 11862). Chitosan, epigallocatechin gallate (EGCG), and garlic were used as natural bioactives for antibacterial activity. The testing method was carried out according to the disk diffusion method. All of chitosan, EGCG, and garlic showed inhibitory effect against the growth of E. coli and Salmonella typhi. To evaluate the antibacterial activity of natural products during storage, chicken skins were inoculated with $10^6$ of E. coli or Salmonella typhi. The inoculated chicken skins, treated with 0.5, 1, or 2% natural bioactives, were stored during 8 day at $4^{\circ}C$. The numbers of microorganisms were measured at 8 day. Both chitosan and EGCG showed significant decrease in the number of E. coli and Salmonella typhi in dose dependent manner (P < 0.05). These results suggest that natural bioactives such as chitosan, EGCG may be possible to be used as antimicrobial agents for the improvement of food safety.

• Journal of Microbiology and Biotechnology
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• v.16 no.3
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• pp.349-354
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• 2006

Furaneol, a key aroma compound found in strawberry, pineapple, and processed foodstuffs, has been known to possess various biological activities on animal models. In this study, the antimicrobial effects of furaneol against human pathogenic microorganisms were investigated. The results indicated that furaneol displayed a broad spectrum of antimicrobial activities against Gram-positive and Gram-negative bacteria and fungi without hemolytic activity on human erythrocyte cells. To confirm the antifungal activity of furaneol, we examined the accumulation of intracellular trehalose as a stress response marker on toxic agents and its effect on dimorphic transition of Candida albicans. The results demonstrated that furaneol induced significant accumulation of intracellular trehalose and exerted its antifungal effect by disrupting serum-induced mycelial forms. These results suggest that furaneol could be a therapeutic agent having a broad spectrum of antimicrobial activity on human pathogenic microorganisms.

• Journal of dental hygiene science
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• v.6 no.4
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• pp.309-311
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• 2006

In order to development of new denture cleaners using natural antimicrobial agents, we have investigated various species of medicinal plants for the antimicrobial activity against Streptococcus matans and Candida albicans. Citrus extract showed significant antifungal activities in a dose-dependent manner against Candida albicans. Candidasis is also a common problem affecting older adults using full denture. We also developed liquid type denture cleaner formulation using citrus extracts.

• Korean Journal of Medicinal Crop Science
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• v.17 no.5
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• pp.335-340
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• 2009

To evaluate the availability of Cudrania tricuspidata Bureau as a natural source of antimicrobials, the antimicrobial activity of methanol extracts of harvested parts was investigated using the paper disc diffusion method. The extracts from leaves and root bark had broad antimicrobial activity against various bacteria, including Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Streptococcus mutans, Listeria monocytogenes, Enterobacter aerogenes, Enterococcus faecalis, Salmonella choleraesuis subsp. choleraesuis, Vibrio vulnificus, and Pseudomonas aeruginosa and inhibited Bacillus cereus, Staphylococcus aureus, and Listeria monocytogenes, agents of food poisoning especially well. The extract from ripe fruit had a very high antimicrobial activity against Staphylococcus aureus with a 20.2 mm of clear zone at 50 mg/mL sample concentration. These results indicated that Cudrania tricuspidata could be used as new source for developing natural antimicrobial agents.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.708-711
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• 2010

We report the isolation and characterization of a novel knottin-type antimicrobial peptide from the yellow-spotted long-horned beetle Psacothea hilaris. A cDNA encoding a 56-mer knottin-type propeptide was identified and its predicted molecular mass and pI were 5.92 kDa and 8.28, respectively. A 34-mer mature peptide was also selected and named herein as psacotheasin. The antimicrobial activity of chemically synthesized psacotheasin against human bacterial pathogens was subsequently investigated. The results showed that psacotheasin exerted potent activities against both Gram-positive and Gram-negative bacterial strains. The present study suggests that psacotheasin can be applied to develop novel therapeutic agents.

• Korean Journal of Pharmacognosy
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• v.27 no.4
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• pp.309-315
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• 1996

As part of our search for less toxic antimicrobial agents from natural resources, antimicrobial activity of rutin isolated from Sophora japonica was tested in vitro against four kinds of gram positive bacteria and four kinds of gram negative bacteria by serial broth dilution method. Among eight kinds of bacteria tested, the antimicrobial activity of rutin was the most potent against Mycobacterium smegmatis showing MIC of $375\;{\mu}g/ml$. The acute toxicity of rutin was examined in mice and rats. and $LD_{50}$ value administered intraperitoneally in mice was 650 mg/kg(Confidence limit: 894-1,473 mg/kg). There were no significant changes in serum biochemical values and histopathological changes as compared with those of control after intraperitoneal administration with rutin in rats.

• The Journal of Natural Sciences
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• v.8 no.2
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• pp.49-55
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• 1996

In order to survey the safety of some food additives, antimicrobial activity of acidulants, stabilizers, antioxidants, natural coloring materials and bleaching agents against 5 strains of bacteria and Sacch. cerevisiae were investigated by dilution method and minimal inhibitory concentration(MIC) method. Malic acid as acidulants displayed the effective antimicrobial activity in vitro against P. aeruginosa and its MIC is 0.05%. Alginic acid and pectin as stabilizer also displayed strong antimicrobial activity against B. subtilis, E. coli and P. aeruginosa, and tannin(antioxidants) and $NaHSO_3$ displayed antimicrobial activity against all bacteria tested. However gums(Arabia, Xanthan, Gua) and natural coloring materials(Hongwha Yellow, Red powder-N) were not affected to growth of bacteria and Sacch. cerevisiae.

• YAKHAK HOEJI
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• v.38 no.6
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• pp.742-748
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• 1994

As part of our search for less toxic antimicrobial agents from natural resources, the carpophores of Elfvingia applanata$(P_{ers}.)K_{ARST}.$ was extracted with hot water. EA, the aqueous extract from the carpophores of E. applanata, was lyophilized and a dark brownish powder was obtained. Antimicrobial activity of EA was tested in vitro against Gram positive and Gram negative bacteria by serial broth dilution method, and the antimicrobial activity was expressed by minimal inhibitory concentration(MIC). Among fourteen species of bacteria tested, the antimicrobial activity of EA was the most potent against Proteus vulgaris showing MIC of 1.250 mg/ml. To investigate the effect of antimicrobial combinations of EA with four kinds of antibiotics(ampicillin, cefazolin, oxytetracycline and chloramphenicol), the fractional inhibitory concentration index(FICI) was determined by checkerboard assay for each strain. The antimicrobial combinations of EA with four kinds of antibiotics resulted in synergism in four instances, but no antagonism was observed. Four instances of synergism were observed when EA was combined with ampicillin against Micrococcus luteus, with cefazolin against Bacillus subtilis, with cefazolin against Micrococcus luteus and with oxytetracycline against Staphylococcus aureus.

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.329-333
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• 1998

The major classes of antimicrobial agents for textiles include organo-metallics, phenols, quaternary ammonium salts, and organo-silicones. These finishes should be durable, have selective activity towards undesirable organisms, be compatible with other finishes and dyes, and be nontoxic to man [1]. Chitosan, as a deacetylated derivative of chitin, is a natural, non-toxic and biodegradable polymer. Chitosan is also known as an antimicrobial polysaccharide due to antimicrobial action of the amino group at the C-2 position of the glucosamine residue.(omitted)

• Journal of Integrative Natural Science
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• v.1 no.1
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• pp.47-53
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• 2008

In a previous study, we showed that Cecropin A (1-8)-Magainin 2 (1-12) hybrid peptide (CA-MA)'s analogue, Anal P5, exhibit broad-spectrum antimicrobial activity. Anal P5, designed by flexible region (positions 9, 10)-substitution, Lys- (positions 4, 8, 14, 15) and Leu- (positions 5, 6, 12, 13, 16, 17, 20) substitutions, showed an enhanced antimicrobial and antitumor activity without hemolysis. The primary objective of the present study was to gain insight into the relevant mechanisms of antimicrobial activities of Anal P5 by using flow cytometric analysis. Anal P5 exhibits strong antifungal activity in a salt concentration independent manner. In addition, Anal P5 causes significant morphological alterations of the bacterial surfaces as shown by scanning electron microscopy, supporting its antibacterial activity. Its potent antibiotic activity suggests that Anal P5 is an excellent candidate as a lead compound for the development of novel antibiotic agents.