• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.545-549
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• 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 Life Science
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• v.12 no.6
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• pp.669-675
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• 2002

Introduction of sliced raw fish meat(SRFM) to fast food business has been considered seriously. However bacteria causing food poisoning should be controlled. Organic acids such as vinegar and lactic acid used in the sauce for SRFM were evaluated for their antibacterial activities. At low concentration levels of vinegar and lactic acid exerted strong antibacterial activities toward Vibriu sp.. In contrast, in case of Salmonella typhimurium and Escherichia coli O157:H7 low anitbacterial activities were observed even at relatively high concentrations. Minimum inhibitory concentrations(MIC) of vinegar for V. vulnificus, V. cholerae non-O1, V. parahaemolyticus, V. mimicus, S. typhimurium and E. coli O157:H7 were 16, 18, 16, 12, 26, and $20{\mu}\ell /m\ell, respertively. MIC of lactic acid for V. vilnificus, V. cholerae non-O1, V. parahaemolyticus, V. mimicus, S. typhimurium and E. coli O157:H7 were 20, 25, 25, 25, 40, and $35{\mu}\ell /m\ell, respectively. In case of vinegar bactericidal concentration upon 10 second contact for V. vulnificus, V. cholerae non-O1, V. parahaenolyticus, V. mimicus and E. coli O157:H7 were 8, 14, 10, 4, and 48%, respectively; however, even at 50% colony of S. typhimurium was observed. In case of lactic acid any colony was observed for V. vulnificus, V. cholerae non-O1, V. parahaemolyticus, V. mimicus, S. typhimurium and E. coli O157:H7 at the concentration of 2, 3, 4, 3, 14, and 17%, respectively. Vinegar and lactic acid of low concentration inhibited the growth of Vibrio sp., food poisoning pathogen in SRFM; in contrast, at high concentration these organic acids inhibited Salmonella sp. and Escherichia sp., food poisoning pathogen in other than SRFM.

• Korean Journal of Poultry Science
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• v.36 no.3
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• pp.231-238
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• 2009

The present study was conducted to investigate the antimicrobial activities of extracts from approximately 40 different traditional Korean medicinal herbs against S. gallinarum and S. epidermidis. The extracts from Schizandra chinensis Baill., Melia azedarach Linn$\acute{e}$, Caesalpinia sappan Linn$\acute{e}$. and Rhus javanica Linn$\acute{e}$. exhibited high antimicrobial activities against S. gallinarum, whereas the extracts from Melia azedarach Linn$\acute{e}$ and Rhus javanica Linn$\acute{e}$. exhibited high antimicrobial growth for S. epidermidis. Minimum inhibitory concentrations (MIC) of Melia azedarach Linn$\acute{e}$, Caesalpinia sappan Linn$\acute{e}$. and Rhus javanica Linn$\acute{e}$. for S. gallinarum were 1.2 mg/mL, whereas MIC of exracts from Rhus javanica Linn$\acute{e}$. extract for S. epidermidis were 0.6 mg/mL. Heat treatment of the extracts from Schizandra chinensis Baill. and Rhus javanica Linn$\acute{e}$. caused a significant reduction in antimicrobial activities against S. gallinarum. but didn't affect antimicrobial activities against S. edidermidis. Alkaline treatment of the extracts from Schizandra chinensis Baill. caused a significant reduction in antimicrobial activities against S. gallinarum, while similar treatment of the extracts from Rhus javanica Linn$\acute{e}$. caused a significant increase in antimicrobial activities against S. edidermidis. Since extracts from Rhus javanica Linn$\acute{e}$. and Caesalpinia sappan Linn$\acute{e}$. exhibited the highest antimicrobial activities, these extracts at the concentrations of 100, 300 or 500 ppm were added and then bacterial growth-inhibiting activities for S. gallinarum and S. epidermidis by these two extracts were further examined. Optical density at 620 nm ($OD_{620}$) after 24 hours incubation in the absence of Rhus javanica Linn$\acute{e}$. extract ranged from 0.30 to 0.45 compared with $OD_{620}$ value ranging from 0.06 to 0.18 in the presence of 100, 300 or 500 ppm of the extract, indicating that growth of all bacteria was significantly inhibited within 24 hours by the addition of at least 100 ppm of Rhus javanica Linn$\acute{e}$ extract. Value of $OD_{620}$ after 24 hours incubation in the absence of Caesalpinia sappan Linn$\acute{e}$. extract ranged from 0.30 to 0.55 compared with $OD_{620}$ value ranging from 0.05 to 0.15 in the presence of 300 or 500 ppm of the extract, indicating that growth of all bacteria was also significantly inhibited within 24 hours by the addition of at least 300 ppm of Caesalpinia sappan Linn$\acute{e}$. extract. In conclusion, these findings suggest that extracts from Rhus javanica Linn$\acute{e}$. and Caesalpinia sappan Linn$\acute{e}$. may play important roles in antimicrobial activities against S. gallinarum and S. epidermidis.

• Journal of the Korean Applied Science and Technology
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• v.33 no.3
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• pp.498-506
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• 2016

1, 2-Hexanediol galactoside (HD-gal) has been previously synthesized from 1, 2-hexanediol (HD), in which recombinant ${\beta}$-galactosidase (${\beta}$-gal) of Escherichia coli (E. coli) was used for transgalactosylation reaction. In this study, a method for HD-gal purification from the reaction mixture was particularly investigated. Using ${\beta}$-gal-containing E. coli, HD-gal was synthesized from 75 mM HD for 48 hr under 300 g/l lactose concentration. Then, HD-gal synthesis from HD was confirmed by TLC analysis, and the existence of E. coli ${\beta}$-gal during 48 hr-reaction was also confirmed by Western blotting, in which the conversion yield of HD to HD-gal reached about 94% during 48 hr. To establish an efficient method for HD-gal purification, we carried out the solvent extraction of the reaction mixture, followed by silica gel chromatography, particularly in order to remove the residual HD. Two water-immiscible solvents, such as methylene chloride and ethyl acetate, were investigated comparatively to find out appropriate solvent. Then, it was found that residual HD was almost removed when ethyl acetate extraction of water phase of reaction mixture was carried out four times. Subsequently, silica gel chromatography was carried out, and purified HD-gal could be finally obtained. The production yield for HD-gal from 75 mM HD was $8.9{\pm}0.6%$ (n=3) (mole basis) or $21.1{\pm}1.4%$ (n=3) (weight basis). For further study, using purified HD-gal, we will investigate the minimum inhibitory concentrations (MICs) of HD-gal against bacteria. In addition, cytotoxicity to human skin cells of HD-gal will be examined.

• The Journal of the Korean Society for Microbiology
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• v.17 no.1
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• pp.21-34
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• 1982

One hundred and twenty-one strains each of Escherichia coli isolated from stools of 60 patients who received various antimicrobial drugs in hospital for more than one week and apparently healthy 60 students who have no history of taking antimicrobial drugs during recent one month, were tested for their resistance to 13 antimicrobial drugs. The frequency of resistance strains was highest to tetracycline with 69.2%, and followed by streptomycin(Sm), sulfisomidine(Su), chloramphenicol(Cm), ampicillin(Ap), and carbenicillin(Cb) in the decreasing order, ranging from 61.2% to 39.3%. Strains resistant to kanamycin(Km), cephaloridine(Cr), and trimethoprim(Tp) occupied about one-fourth of strains, and only four strains were resistant either one or more of nalidixic acid, gentamicin and amikacin, and no strain was resistant to rifampicin. The frequency of resistant strains to Cm, Ap, Km, Cr, and Cb was much higher among patient isolates than student strains, but strains resistant to the other drugs showed almost the same frequencies between patient and student isolates. There was a marked difference in average minimum inhibitory concentrations of between resistant and susceptible strains, suggesting that the resistance to drugs is the plasmid origin. Seventy-six percent of strains were resistant to one to 10 drugs tested, and no much difference was observed between strains from patients and students. However, strains resistant to four or more drugs were much more frequently found among patient isolates than student strains, with the increasing tendency of multiply resistant strains among patient isolates following the increase in the number of resistant drugs. The transfer of drug resistance by conjugation was tested and 98 strains(67.5%) among 145 which were resistant to two or more drugs were found to transfer their drug resistance to E. coli. Among 74 strains resistant to 7 or more drugs, all except one transferred the resistance, and the number of strains with transferable resistance decreased, as the number of resistant drugs decrease. A R plasmid from randomly selected p13 strain was tested for the incompatibility group, and the plasmid was classified into Inc F II. R plasmM DNA bands were identified by polyacrylamide gel electrophoresis.

• Microbiology and Biotechnology Letters
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• v.41 no.3
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• pp.284-291
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• 2013

In this study, the antibacterial and antioxidative activities of Epimedium koreanum Nakai were investigated for applications as cosmetic ingredients. Minimum inhibitory concentrations (MICs) of fraction-bacterium, that showed high antibacterial activity from disc diffusion assay on human skin pathogens, were tested. The ethyl acetate fraction on Staphylococcus aureus, Bacillus subtilis, Propionibacterium acnes and 50% ethanol extract on S. aureus exhibited higher antibacterial activities than methyl paraben, well known as a preservative. The DPPH (1,1-diphenyl-2-picrylhydrazyl) scavenging activities of 3 fractions of E. koreanum Nakai were lower than (+)-${\alpha}$-tocopherol, known as a typical antioxidant. From the results of the scavenging activities of various ROS generated in $Fe^{3+}-EDTA/H_2O_2$ systems ($OSC_{50}$), 50% ethanol extract ($OSC_{50}=2.46{\pm}0.06{\mu}g/ml$) and aglycone fraction ($OSC_{50}=1.45{\pm}0.02{\mu}g/ml$) showed high activities similar to L-ascorbic acid ($OSC_{50}=1.50{\pm}0.85{\mu}g/ml$), used as reference. The cellular protective effects (${\tau}_{50}$) on photohemolysis by $^1O_2$ generated by photosensitization reaction were tested. The cellular protective effect of 50% ethanol extract (${\tau}_{50}=37.0{\pm}0.3$ min) was similar to (+)-${\alpha}$-tocopherol (${\tau}_{50}=38.0{\pm}1.8$ min), used as reference. In particular, the ${\tau}_{50}$ of aglycone fraction results were $165.9{\pm}7.2$ min. This is a high cellular protective effect, more than 4 times that of (+)-${\alpha}$-tocopherol. These results indicate that E. koreanum Nakai extract, and its fractions, could be utilized as a cosmetic ingredient possessing antibacterial and antioxidative activities.

• Journal of Life Science
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• v.15 no.3 s.70
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• pp.479-485
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• 2005

The 994 throat swabs obtained from 688 adults and 306 children patients with respiratory diseases were examined for Mycoplasma pneumoniae infection by culture method. Antimicrobial susceptibilities of the resulting 123 M. pneumoniae isolates were evaluated by testing minimum inhibitory concentrations (MICs) of erythromycin, minocycline, tetracycline, josamycin, sparfloxacin, ofloxacin, and ciprofloxacin by a broth micro-dilution method. The erythromycin resistant strains of M. pneumoniae was determined above $1.0{\mu}g/ml$ of MIC for erythromycin. The erythromycin resistant strains of M. pneumoniae was confirmed resistant gene mutation of the portions of genes 23S rRNA (domain II and V), and ribosomal protein 14 and L22 by PCR amplified and their nucleotide sequenses were compared to those of the susceptible strain M129. The isolation rate of M. pneumoniae was $12.9\%$ (89/688) for the adults and $11.1\%$ (34/306) for the children. The $MICs_{90}$ of the M. pneumoniae isolates were $0.12{\mu}g/ml$ for minocycline, $0.25{\mu}g/ml$ for sparfloxacin, $0.5{\mu}g/ml$ for ciprofloxacin, ofloxacin, and tetracycline, respectively, and $2.0{\mu}g/ml$ for josamycin and erythromycin, respectively. The isolation rate of erythromycin resistant M. pneumoniae from patients was $49.4\%\;(44/89)$ for the adults, $47.1\%\;(16/34)$ for children, and $48.8\%\;(60/123)$ for the total. No mutation could be detected in the ribosomal protein L22 region, but all strains were mutated in the ribosomal protein L4 as two point mutation M144V. Two point mutations in domain V of 23S rRNA were selected in the presense of erythromycin resistant M. pneumoniae isolates, such as one strain was G2057C mutant, two strains were A2059C mutants, three strains were C2611G mutants, four strains were A2058C mutants, five strains were A2058T mutants, twenty strains were A2059G mutants, and twenty-five strains were A2058G mutants, respectively. These results show that erythromycin was not the most active compound against M. pneumoniae infection in Korea and clinical studies of macrolides in human patients are demanded.

• Korean Journal of Plant Resources
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• v.19 no.4
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• pp.491-496
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• 2006

Antimicrobial activity of 18 different traditional medicinal herbs extracts against Staphylococcus aureus was determined by a paper disc method. The Prunella vulgaris, Caesalpinia sappan and Rhus javanica extracts in 5 mg/ml, Poncirus trifoliata, Lonicera japonica and Seutellaria baicalensis extracts in 10 mg/ml and Schizandra chinensis, Alpinia katsumadai, Siegesbeckia orientalis extracts in 30 mg/ml showed a significant antimicrobial activity against Staphylococcus aureus. Minimum inhibitory concentrations of medicinal herbs extracts were in the range of $1{\sim}34\;mg/ml$ and $1{\sim}46\;mg/ml$, in the case of MeOH extracts and EtOH extracts, respectively. In addition, the antimicrobial activity of each solvent fraction was most significant with EtOAc layer. Optical density at 620nm after 24 hours incubation of Staphylococcus aureus in the presence of 100, 300 or 500 ppm of Caesalpinia sappan extract ranged from 0.02 to 0.03 compared to 0.4 in the absence of Caesalpinia sappan extract, indicating that growth of Staphylococcus aureus was significantly inhibited within 24 hours by the addition of at least 100 ppm of Caesalpinia sappan extract. Optical density at 620 nm after 24 hours incubation of Staphylococcus aureus in the presence of 300 ppm of Rhus javanica extract ranged from 0.02 to 0.03 compared to 0.4 in the absence of Rhus javanica extract, indicating that growth of Staphylococcus aureus was also significantly inhibited within 24 hours by the addition of at least 300 ppm of Rhus javanica extract. Optical density at 620 nm after 24 hours incubation of Staphylococcus aureus in the presence of 300 ppm of Seutellaria baicalensis extract ranged from 0.02 to 0.07 compared to 0.4 in the absence of Seutellaria baicalensis extract, indicating that growth of Staphylococcus aureus was also significantly inhibited within 24 hours by the addition of at least 300 ppm of Seutellaria baicalensis extract. In conclusion, these findings suggest that extracts from medicinal herbs may play important roles for antimicrobial activities against Staphylococcus aureus.

• Korean Journal of Microbiology
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• v.42 no.3
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• pp.185-194
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• 2006

The aim of this study was to identify the bacteria isolated from endodontic lesions by cell culture and to determine the antimicrobial susceptibility of them against 8 antibiotics. The necrotic pulpal tissues were collected from 27 infected root canals, which were diagnosed as endodontic infection. Samples were collected aseptically from the infected pulpal tissue of the infected root canals using a barbed broach and a paper point. The cut barbed broaches and paper points were transferred to an eppendorf tube containing $500{\mu}l\;of\;1{\times}PBS$. The sample solution was briefly mixed and plated onto a BHI-agar plate containing 5% sheep blood. The agar plates were incubated in a $37^{\circ}C$ anaerobic chamber for 2 to 5 days. The bacteria grown on the agar plates were identified by comparison of 16S rRNA gene (rDNA) sequencing method at the species level. To test the sensitivity of the bacteria isolated from the infected root canals against 8 antibiotics, minimum inhibitory concentrations (MIC) were determined using broth dilution assay. The data showed that 101 bacterial strains were isolated and were identified. Streptococcus spp. (29.7%) and Actinomyces spp. (21.8%) were predominantly isolated. The 9 strains were excluded in antimicrobial susceptibility test because they were lost during the experiment or were not grown in broth culture. The percentage of bacteria susceptible for each antibiotic in this study was clindamycin, 87.0% (80 of 92); tetracycline, 75.0% (69 of 92); cefuroxime axetil, 75.0% (69 of 92); amoxicillin + clavulanic acid (5:1), 71.7% (66 of 92); penicillin G, 66.3% (61 of 92); erythromycin, 66.3% (61 of 92); amoxicillin, 44.6% (41 of 92); and ciprofloxacin, 31.5% (29 of 92). The susceptibility pattern of 8 antibiotics was dependent on the host of the bacteria strains rather than the kinds of bacterial species. These results indicate that antibiotic susceptibility test should be performed when antibiotics are needed for the treatment of infected root canals.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.1
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• pp.47-55
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• 2011

The solvent extracts of Aruncus dioicus var. kamtschaticus Hara, which were extracted by using several solvents with different polarities, were performed to investigate the antioxidant activities, whitening effect and antimicrobial activity. The content of total polyphenol of fractions from Aruncus dioicus var. kamtschaticus Hara extract showed the highest value ($335.88{\pm}2.26$ mg/g GAE) on ethyl acetate fraction. The ethyl acetate and n-butanol fractions were 0.06 mg/mL and 0.25 mg/mL as $IC_{50}$ values on DPPH radical scavenging, and $99.16{\pm}0.09%$ and $89.29{\pm}0.64%$ on ABTS radical scavenging activity, respectively. Also, reducing power and FRAP value were significantly higher on ethyl acetate fraction. The SOD like activity showed $80.76{\pm}0.61%$ on ethyl acetate and $72.34{\pm}0.79%$ on n-butanol. Tyrosinase inhibition activities (at 5 mg/mL) were $59.08{\pm}0.98%$ on ethyl acetate fraction. The chloroform fraction showed the strongest antimicrobial activities against B. cereus (14 mm), B. subtilis (12.5 mm), S. aureus (10.8 mm), E. coli (20.7 mm) at 0.1 mg/disc and the inhibition zone diameter of ethyl acetate fraction was 17.2 mm against E. coli at 0.5 mg/disc. The minimum inhibitory concentrations (MIC) of chloroform fraction against B. cereus and E. coli were 50 and $25{\mu}g$/mL, respectively. From these results, it is suggested that ethyl acetate and n-butanol fractions of Aruncus dioicus var. kamtschaticus Hara could be used as functional material for food additive ingredient and chloroform fraction could be suitable for the development of a food preservative.