• Journal of Environmental Science International
• /
• v.3 no.2
• /
• pp.101-109
• /
• 1994

Chlorinated water in swimming pools contains chloroform at elevated levels compared to chlorinated drinking water Chloroform levels in four indoor swimming pools(swimming pools A, B and C in a city of Korea and swimming pool D in a city of New Jersey in the United States) were examined. The chloroform levels in the water of swimming pool C (city-managed) weve shown to be significantly(p=0.0001) different from those of private swimming pools A and B: the mean chloroform levels in the pools A, B, and C are 22.8, 17.8, and 31.1 $\mu\textrm{g}$/l, respectively. Furthermore, all of these chloroform levels are significantly(P=0.0001) different from those of New Jersey: chloroform concentration of the Korean pools ranged from 10.9 $\mu\textrm{g}$.l to 47.9 $\mu\textrm{g}$/l with a mean of 23.2 $\mu\textrm{g}$/l, while it ranged from 27 $\mu\textrm{g}$/l to 96$\mu\textrm{g}$/l with a mean of 64.4 $\mu\textrm{g}$/l in the New Jersey pool. The disinfection processes would cause part of this difference since the swimming pools in Korea applied both chlorination and ozonation method, while the swimming pool in New Jersey used chlorination method only. It was implied that swimming parameters inconsistently vary, resulting in fluctuation of and no constant accumulation of chloroform in the water with the change of time for the day. A regression analysis showed no relationships between sampling time and chloroform concentrations for the sampling day in the swimming pools of Korea. A F-test indicated no significant difference of chloroform concentrations in the morning and afternoon samples collected in the swimming pools. Ingestion dose was estimated to be 0.58$\mu\textrm{g}$ from an hour swimming in a city of Korea, taking into accounting an average of 23.2 $\mu\textrm{g}$/l in swimming pools in the city In extreme situation, the ingestion dose was estimated to be 12.0 $\mu\textrm{g}$ from an hour swimming in a city of Korea.

• Korean Journal of Food Science and Technology
• /
• v.44 no.2
• /
• pp.240-246
• /
• 2012

This study evaluated the efficacy of strong acidic electrolyzed water (SAcEW), low alkaline electrolyzed water (LAlEW) and aqueous chlorine dioxide (ACD) for reducing pathogenic bacteria($Escherichia$ $coli$, $Bacillus$ $cereus$, $Salmonella$ Typhimurium, $Stapylococcus$ $aureus$) on Chinese cabbage. Artificially inoculated Chinese cabbage was immersed for 1, 5 and 10 min with TW, NaClO, EW and ACD. Generally, leaves showed more effective reduction than stems. Regarding the inhibitory effect, ACD treatment showed the highest effects rather than other treatments. When Chinese cabbage was immersed for 3 min in sterilized water, it was reduced to a minimum of 1.33 log CFU/g at LAlEW and a maximum of 4.70 log CFU/g at ACD. Compared to NaClO, ACD and LAlEW which showed a reduction of 3.2 log CFU/g ($Sal.$ Typhimurium) and 2.7 log CFU/g($B.$ $cereus$), respectively. Furthermore, the others had similar inhibitory effects compared to NaClO.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.35 no.2
• /
• pp.225-234
• /
• 2008

Recently interesting in development of antimicrobial agent from natural origin has been increased in these days. Many studies have been reported antimicrobial effect of Horseradish(Armoracia rusticana) root extracts against various microorganisms such as Escherichia coli, Salmonella typhimurium, Pseudomonas aeruginosa, Vibrio parahaemolyticu, Staphylococcus aureus, Bacillus subtilis, Aspergillus parasiticus, Helicobacter pylori. The main component related to antimicrobial activity in horseradish is well known as allyl isothiocyanate(AIT). In this study, we investigated the antimicrobial effects of Horseradish(Armoracia rusticana) root extracts against Streptococcus mutans isolated from human dental plaque, Streptococcus mutans reference strain and compared with that of chlorhexidine. Horseradish root extracts and chlorhexidine were tested to determine their minimum inhibitory concentration( MIC) and minimum bactericidal concentration(MBC). The result of this study can be summerized as follows; 1. Horseradish root extracts showed antimicrobial effect against both S. mutans isolated strain and reference strain, their MIC were respectively $0.083{\sim}0.25%$ ($833.33{\sim}2500 ppm$), 0.25% (2500 ppm). Horseradish root extracts showed antimicrobial effect against S. mutans isolated strain at same or slightly lower concentration compared with MIC of reference strain. 2. $0.083{\sim}0.25%$ horseradish root extracts showed similar antimicrobial effect with chlorhexidine ($0.0021{\sim}0.0041%$).

• Microbiology and Biotechnology Letters
• /
• v.38 no.3
• /
• pp.289-294
• /
• 2010

Salvia miltiorrhiza Bunge (S. miltiorrhiza) is a traditional Korean medicine that is commonly used for the treatment of inflammatory diseases such as edema, arthritis, and hepatitis. The present study investigated the antimicrobial activity of methanol (MeOH) extract of S. miltiorrhiza roots against oral bacteria using broth the microdilution method and the checkerboard and time-kill methods evaluated the synergistic effects of treatment with antibiotics. The MeOH extract was demonstrated as a higher antibacterial activity (MICs, 8 to $64\;{\mu}g/mL$; MBCs, 16 to $64\;{\mu}g/mL$) against all tested oral bacteria. Additionally, the extract was observed to have a synergistic effect with ampicillin or gentamicin. A time-kill study evaluating the effects of the extract indicated that the extract treatment in combination with ampicillin or gentamicin showed rapid bactericidal activity. The results suggest that MeOH extract of S. miltiorrhiza could be employed as a natural antibacterial agent against dental caries.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.34 no.5
• /
• pp.545-549
• /
• 2001

To develop a natural antibacterial agent for fish bacterial diseases, antibacterial activity, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and bactericidal effect of cinnamon bark extract were examined against fish pathogenic bacteria. The antimicrobial effect of the extract to the fish diet was also estimated, Cinnamon bark extract showed the broad spectrum of antibacterial activity against fish pathogenic bacteria, especially, it had strong activity against Streptococcus iniae, Edwardsiella tarda and Listonella anguillarum. Its MIC was $75.8\sim189.6{\mu}g/mL$ against Cram positive bacteria, and $75.8\sim113.8{\mu}g/mL$ against Gram negative bacteria in liquid medium, It was found to show stronger bactericidal action against Gram negative bacteria than Cram positive bacteria. According to increasing concentrations of the extract, it resulted in a proportional reduction of viable cell counts of both S. iniae and L. anguillarum. The former was not detected by addition of $189.6{\mu}g/mL$ after 12 hours incubation and the latter by addition of $151.6{\mu}g/mL$ after 24 hours incubation, respectively. It was reasonable that fish diet was soaked in cinnamon bark extract for ten minutes. The relationship formula between the weight of fish diet and the extract absorbed to fish diet was Y=7.2726X+4.5083 ($R^2=0.9998$). The fish diet soaked in the extract inhibited the growth of all strains used in this study. Its antibacterial activity was stable at the range from $10^{\circ}C\;to\;35^{\circ}C$ during the storage period of 28 days. When the diet soaked in the extract was incubated in liquid medium at $35^{\circ}C$, it inhibited the growth of microorganisms inhabited in the diet.

• Journal of the Korean Applied Science and Technology
• /
• v.37 no.4
• /
• pp.1020-1033
• /
• 2020

This study attempted to investigate the usefulness of Rhus javanica L., Cinnamomum verum and Rosmarinus officinalis extracts which have antimicrobial and antioxidant effects without any harm on human health as natural preservatives. In terms of extraction, extraction by 70% ethanol and hot-water extraction were used for Cinnamomum verum and Rhus javanica L. respectively. For Rosmarinus officinalis, a mixed method (70% ethanol and hot-water extraction) was adopted. In terms of experimental methods, antimicrobial effects, antioxidant activity through DPPH and safety and stability of cosmetics were assessed, and a challenge test was performed, and the results found the followings: According to an antimicrobial test, good antimicrobial effects were found in bacteria (Rhus javanica L. extract) and fungi (Cinnamomum verum extract). In contrast, the Rosmarinus officinalis extract was set aside because of poor antimicrobial activity. In the mixed extract (Rhus javanica L. + Cinnamomum verum), antimicrobial effects were observed in 'complex C (mixed in a 1:1 ratio)' while both inhibitory and sterilizing effects were found in 5 different test strains at minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). In addition, antioxidant effects were detected in non-mixed extract and mixed extract ('complex C'). Furthermore, a test on cosmetics which adopted '10% complex C' instead of synthetic preservative revealed safety and stability. Therefore, this study has confirmed the potential of the Rhus javanica L., Cinnamomum verum and Rosmarinus officinalis extracts as materials for natural preservatives.

• Journal of Oral Medicine and Pain
• /
• v.32 no.1
• /
• pp.45-55
• /
• 2007

Plant extract has attracted considerable interest in oral disease therapy. The present study was performed to observe the antibacterial effect on cariogenic Streptococcus mutans GS5 and Streptococcus sobrinus 6715, and periodontopathic Actinobacillus actinomycetemcomitans Y4 of phytoncide from Chamaecyparis obtusa Sieb. et Zucc employing the measurement of optical density, viable cell counts, and antibiotic sensitivity. The results were as follows: 1. Minimum inhibitory concentration of the phytoncide for S. mutans, S. sobrinus, and A. actinomycetemcomitans was observed to be 0.5%, 1%, and 0.2%, respectively. 2. Minimum bactericidal concentration of the phytoncide for S. mutans, S. sobrinus, and A. actinomycetemcomitans was determined to be 0.5%, 2%, and 0.2%, respectively. 3. The bacteria exposed to the phytoncide become more sensitive to antibiotics. The phytoncide enhanced significantly antibacterial activity of ampicillin against S. mutans and S. sobrinus. It also increased significantly the activity of penicillin and amoxicillin against S. sobrinus. In contrast, the phytoncide augmented the activity of amoxicillin and cefotaxime against A. actinomycetemcomitans but the increase was not statistically significant. The overall results indicate that phytoncide from Chamaecyparis obtusa Sieb. et Zucc used for this study has a strong antibacterial activity against cariogenic and periodontopathic bacteria and that it also has permeabilizing effect on certain antibiotics against these bacteria. Therefore, the phytoncide may be used as a candidate for prevention and therapeutic agent against oral infectious disease including dental caries and periodontal disease.

• The Korean Journal of Mycology
• /
• v.34 no.1
• /
• pp.22-28
• /
• 2006

Attempts were made to control Diatrype stigma occurred on the bed-log of Shiitake using wood vinegar, Pinus koraiensis extract, Piper nigrum extract, and fungicides. Mycelial growth of D. stigma was inhibited completely at 35,000 ppm and no ascospore germinated at 25,000 ppm wood vinegar. Inhibition rates of Pinus koraiensis extract (200 ppm), and Piper nigrum extract (1,000 ppm) to ascospore germination were 98.9% and 95.9%, respectively. In fungicide selection, minimum inhibitory concentration (MIC) of benomyl, carbendazim, and thiabendazole ranged $0{\sim}0.4\;{\mu}g\;a.i/m{\ell}$. Difenoconazole at $0.08\;{\mu}g\;a.i/m{\ell}$ inhibited 98.9% of ascospore germination. Inhibition efficacy of fungicides was not highly variable among the low-, middle-, and high-temperature type strains of shiitake. Benomyl, carbendazim, thiabendazole and thiophanate-methyl could not suppress the mycelial growth of Shiitake. Tebuconazole at $0.4\;{\mu}g\;a.i/m{\ell}$ suppressed 80% of the mycelial growth and it was the highest inhibition rate among the fungicides. In field trials, wood vinegar, Pinus koraiensis extract, Piper nigrum extract, and fungicides were sprayed on the bed-logs before or after D. stigma produced pycnidia. Wood vinegar at 150,000 ppm concentration, showed control effect of 72.7% in the treatment before pycnidiospore formation. On the other hand, 70,000 ppm wood vinegar and 1,000 ppm of thiophanate-methyl showed control effects of 58.1% and 52.3% in the treatment after pycnidiospore formation.

• Journal of Oral Medicine and Pain
• /
• v.30 no.1
• /
• pp.1-14
• /
• 2005

The maintenance of good oral health in adults is often hindered by oral malodor and periodontal diseases which are known to be commonly caused by some species of Gram-negative anaerobic bacteria, with low sensitivity to common synthetic antibiotics or antibacterial chemical agents. Therefore the development of a nonharmful natural antibacterial oral rinsing remedy against the causative bacteria is thought to be very important. The purpose of this study is to obtain the basic data for development of a nonharmful natural antibacterial oral rinsing remedy using colloidal silver. The author applied colloidal silver solution with concentration of 10, 30, 50, 80 ppm to some strains in species of Prevotella intermedia, Porphyromonas gingivalis, Fusobaterium nucleatum, and evaluated the effects of colloidal silver on the growth of experimental bacterial strains in aspects of minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC) and growth pattern after incubation for 24, 48, 72 hours. The obtained results were as follows: MIC of colloidal silver solution against experimental strains was 30 ppm in P. intermedia, 10 or 30 ppm in P. gingivalis, and 30, 50, or 80 ppm in F. nucleatum. And MBC of colloidal silver solution against experimental strains was 30 ppm in P. intermedia, 30 or 50 ppm in P. gingivalis, 30 or 80 ppm in F. nucleatum. Therefore it was concluded that colloidal silver exhibited bacteriostatic or/and bacteriocidal effects against some experimental strain. And the inhibition of growth of experimental strains were markedly or considerably exhibited under 30 ppm$\sim$50 ppm of colloidal silver solution for 48 hours$\sim$72 hours in P. intermedia, 10 ppm$\sim$30 ppm for 24 hours$\sim$48 hours in P. gingivalis, 30 ppm for 24 hours in F. nucleatum. These results indicate that the colloidal silver inhibited effectively the growth of some species of Gram-negative anaerobic bacteria by exhibition of bacteriostatic or/and bacteriocidal effects, and can be used as a possible major ingredient of the nonharmful natural antibacterial oral rinsing remedy to oral malodor and periodontal diseases.

• Korean Journal of Environmental Agriculture
• /
• v.22 no.3
• /
• pp.227-232
• /
• 2003

This study was conducted to evaluate the terminal residue of a new fungicide, KNF 1002, in cucumber and pepper under greenhouse and field conditions. When a microemulsion formulation (20%) of KNF 1002 was applied once or twice during $1{\sim}7$ days before harvest, its terminal residue in cucumber ranged <$0.02{\sim}0.20\;mg/kg$ under greenhouse condition. In pepper, its figure recorded $0.31{\sim}0.79\;mg/kg$ and $0.11{\sim}0.28\;mg/kg$ under greenhouse and field conditions, respectively. Much higher level of terminal residues was observed in leaves than those in fruits in pepper, showing $7.38{\sim}25.20\;mg/kg$ and $0.11{\sim}1.99\;mg/kg$ under greenhouse and field conditions, respectively. Cultivation condition affected evidently the residue level in pepper harvests. Residual pattern of KNF 1002 seemed to be comparable to strobilurin fungicides currently used.