• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.187-194
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• 2015

In this study, L. plantarum, when reacting with the culture media of potential pathogenic bacteria, exhibited an increase in growth rate and antimicrobial activity. In order to examine the characteristics and the nature of the reaction with the bacteria, this study carried out experiments involving culturing the test bacteria in M9 minimal media. Subsequently, the supernatant was incrassated by the decompression-drying method. Through colony forming unit assay, it was confirmed that L. plantarum had the function of growth inhibition to various bacteria. After culturing L. plantarum with bacterial media, the growth rate of L. plantarum was measured by absorbance (OD₆₀₀), the results showed that the growth rate (E. coli treatment group: OD₆₀₀ = 0.848, S. typhimurium treatment group: OD₆₀₀ = 0.848) increased, as compared with the non-treated control group (OD₆₀₀ = 0.48). In contrast, the concentrate itself did not induce the growth of L. plantarum. These results were observed as a universal phenomenon of the Lactobacillus species. Moreover, the increase in antimicrobial activity was observed in L. plantarum, which reacted with the culture media of E. coli and S. typhimurium, through a disc diffusion assay, and the result of growth inhibition against various bacteria was induced. Finally, based on the analysis results of the characteristics of bacteria culture media, which increased the growth rate of L. plantarum and antibacterial activity, the bacterial media had a tolerance for catabolic enzymes, pH 2−8 and heat. Therefore, this substance can be said to be a small molecule which is highly stable under various conditions.

• Journal of Microbiology and Biotechnology
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• v.12 no.4
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• pp.610-616
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• 2002

The growth-inhibiting effects of Pinus densiflpora leaf-derived materials on nine human intestinal bacteria were investigated using the impregnated paper disk method, and their activities were compared with those of 13 commercially available terpenes. The biologically active constituent of the extract of P densiflora leaf was characterized as the monoterpene (1R)-(+)-$\alpha$-pinene by various spectroscopic analyses. Responses varied according to bacterial strain, chemicals, and dose. At 10 mg/disk, limonene and (1R)-(+)-$\alpha$-pinene strongly inhibited the growth of Clostridium perfringens, Staphylococcus aureus, and Escherichia coli, without adverse effects on the growth of five lactic acid-bacteria (Bifidobacterium adolescentis, B. bifidum, B. longum, Lactobacillus acidophilus, and L. casei). Little or no inhibition against seven bacteria was observed with anethole, borneol, camphor, caryophyllene, 1,8-cineole, estragole, linalool, and $\alpha$-terpineol. Structure-activity relationship revealed that (1R)-(+)-$\alpha$-pinene had more growth-inhibiting activity against C. perfringens than (1R)-(+)-$\beta$-, (1S-(-)-$\alpha$-, and (1S-(-)-$\beta$-pinenes. Furthermore, the growth-inhibition against L. casei was much more pronounced in (1R)-(+)-$\beta$- and (In-(-)-$\beta$-pinenes than (1R)-(+)-$\alpha$- and (1S)-(-)-$\alpha$-pinenes. These results indicate that the (+)-$\alpha$ form seems to be required against C. perfringens and $\beta$ form against L. casei for growth-inhibiting activity. Morphologically, most strains of C. perfringens were damaged and disappeared at 5 and 2 mg/disk of (1R)-(+)-$\alpha$-pinene. Morphological study revealed that (1R)-(+)-$\alpha$-pinene had more growth-inhibiting activity against C. perfringens than (1R)-(+)-$\beta$-, (1S)-(-)-$\alpha$-, and (1S)-(-)-$\beta$-pinenes. As naturally occurring growth-inhibiting agents, the Pinus leaf-derived materials described above could be useful preventive agents against diseases caused by harmful intestinal bacteria such as clostridia.

• Proceedings of the Korean Society of Food and Cookery Science Conference
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• 2003.10a
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• pp.75-75
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• 2003

The objective of this study is to investigate the effect of Codonopsis lanceolata Bentk et Hook on the growth of lactic acid bacteria and some harmful bacteria. Extract of C. lanceolata was obtained by hydrothermal extraction method and used intactly without concentration. To investigate the inhibitory effect on the growth of harmful bacteria, we used agar dilution method. On agar plate containing more than 25% extract, they showed decreased number of colonies. (omitted)

• Journal of Korean Society of Water and Wastewater
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• v.24 no.2
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• pp.165-172
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• 2010

Treated sewage could enable growth by providing key nutrients or seeding the sediments with enterococci strains that can grow in the environment. This study is to test the hypothesis that the flux of bacteria into the water column is rate-limited by the transfer of bacteria across the sediment/water interface. Two conceptual models are derived for the transfer of bacteria to the water column from the sediment/water interface: convective diffusion of isolated bacteria and resuspension of particle-associated bacteria. The model predictions are directly tested together with field measurements of bacteria and sediment in an effluent-dominated stream where high concentrations of enterococci in this stream originate primarily from growth of the bacteria in stream sediments. The results reveal that high concentrations of enterococci in this stream are transported primarily by resuspension of particle-associated bacteria accumulated at the sediment/water interface, either in the form of bacterial aggregates or in the form of inorganic particles.

• Korean Journal of Environmental Agriculture
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• v.39 no.1
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• pp.20-25
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• 2020

BACKGROUND: Marine algae is a productive organism that is consumed as a nutritious food. However, large amounts of unused portions of the algae are incinerated as trash or dumped in the sea, causing pollution. Recycling algae is important for saving resources and conserving the environment. In this study, the fucoidan which is a major carbohydrate of marine algae was tested as a source of fertilizer for farming. METHODS AND RESULTS: The growth rate of the melon was examined after treating fucoidan and the melon growth factors, weight and length of stem were measured. To discover the mechanism of melon growth promotion of fucoidan, bacteria that decomposed fucoidan were isolated from soil and abalone. Bacillus wiedmannii and Stenotrophomonas pavanii were isolated from terrestrial soil and Pseudomonas sp. was isolated from abalone. Among these three bacteria, Pseudomonas sp. had the highest and most specific fucoidan-decomposing activity. When Pseudomonas sp. was treated with fucoidan on melon-growing soil, the growth of melon was relatively improved compared to the treatment with fucoidan alone. CONCLUSION: We found that fucoidan, the main carbohydrate of marine algae, promoted melon growth. Fucoidan-decomposing microorganisms were isolated from terrestrial soil and marine organism, and we found that these bacteria stimulated the effect of melon growth promotion of marine algae. This is the first report that confirms the fertilizer effect of marine algae and shows the use of bacteria with marine algae.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.24 no.2
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• pp.117-122
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• 1991

Microbial organisms including yeast, Acinetobacter sp. AG-3, Chlorococcum sp., Chlorella sp. and some of their combinations were tested to evaluate growth efficiency of Tigriopus japonicus. Body length and weight of the copepoda were measured during four days experiment. Acinetobacter sp. AG-3, dried yeast(produced Wago), Chlorella sp., Chlorococcum sp. and mixed culture were used as food sources. Yeast(Y.) was the most effective food for the growth during nauplius stage and efficiencies of bacteria(Bact.)+chlorococcum sp.(RA), Chlorococcum sp.(RA), Bact.+chlorella sp.(Ch.), Bact. and Ch. decreased in odor, while for the growth of copepodite and adult, Bact.+RA was the most effective food with decreased efficiency of Y., RA, Bact. + Ch., Bact., Ch. in order. The ratio of weight gain to the food uptaken, after the weight and food units were converted to carbon, was between 21.6 and $68.7\%$, This result suggests that some kinds of bacteria, algae and mixed cultural microorganisms could be good food sources for the growth of copepoda.

• Journal of Dairy Science and Biotechnology
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• v.39 no.3
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• pp.121-127
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• 2021

Yogurt is produced by bacterial fermentation of milk and contains lactic acid bacteria (LAB), which produce various metabolites such as organic acid, hydrogen peroxide, and bacteriocin. This study aimed to investigate cell-free supernatants (CFS) of LAB isolated from Tibetan yogurt. CFS (TY1, TY2, TY3, TY4, TY5, TY6, and TY7) from selected strains of LAB were co-incubated with four different foodborne pathogenic bacteria, namely E. coli O157:H7, Listeria monocytogenes, Salmonella typhimurium, and Staphylococcus aureus. Inhibition of foodborne pathogenic bacterial growth was not affected in the presence of CFS (pH 6.5). In contrast, CFS without neutralization completely inhibited the growth of the bacteria. Furthermore, when the concentration of CFS (without neutralization) was changed to 1:4 and 1:8, a difference in inhibition was observed between Gram-positive and Gram-negative bacteria. CFS more effectively inhibited the growth of Gram-negative E. coli O157:H7 and S. Typhimurium than Gram-positive L. monocytogenes and S. aureus. These results suggest that organic acids in LAB may inhibit the growth of foodborne pathogenic bacteria, particularly Gram-negative bacteria.

• Journal of the East Asian Society of Dietary Life
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• v.16 no.3
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• pp.344-348
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• 2006

This study was carried out to survey the effect of medicinal herbs on the growth of 3 strains of lactic starter cultures in MRS broth by the addition of 0, 1, 3, 5, and 10% water extract, after 30 hrs incubation. The pH, titratable acidity and O.D. of lactic acid bacteria were investigated to obtain fundamental knowledge for the development a new product. The effects of medicinal herbs extracts on the growth of lactic acid bacteria were variable depending upon the species of lactic acid bacteria and medicinal herbs extract. Growth of Str. thermohilus was activated by addition of 1 and 3% Angelica gigas water extract, but the basal medium plus 5 and 10% extract and growth of L. acidophilus and Bif. longum were depressed by the addition of extract. The pH and acid production ability dropped slightly in the basal medium plus 1 and 3% of extract. The other samples following the same trend as the control.

• Journal of Environmental Science International
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• v.21 no.3
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• pp.267-276
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• 2012

Spaceflights results in the reduction of immune status of human beings and increase in the virulence of microorganisms, especially gram negative bacteria. The growth of Klebsiella pneumoniae is enhanced by catecholamines and during spaceflight, elevation in the levels of cortisols occurs. So it is necessary to know the changes in physiology, virulence, antibiotic resistance and gene expression of K. pneumoniae under microgravity conditions. The present study was undertaken to study effect of simulated microgravity on growth, morphology, antibiotic resistance and cross stress resistance of K. pneumoniae to various stresses. The susceptibility of simulated microgravity grown K. pneumoniae to ampicillin, penicillin, streptomycin, kanamycin, hygromycin and rifampicin were evaluated. The growth of bacteria was found to be fast compared with normal gravity grown bacteria and no significant changes in the antibiotic resistance were found. The bacteria cultured under microgravity conferred cross stress resistance to acid, temperature and osmotic stress higher than the normal gravity cultured bacteria but the vice versa was found in case of oxidative stress.

• Preventive Nutrition and Food Science
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• v.6 no.3
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• pp.192-196
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• 2001

Ethanol extracts from 36 vegetable samples were assayed for their growth-promoting effects on Bifidobacterium bifidum, B. longum, and Lactobacillus casei The growth-promoting effects varied according to bacterial strain and vegetable species. In modified Gy rgy broth, extracts of Lactuca sativa, Lycopersicon esculentum and L escutentum var. cerasiforme exhibited strong growth-promoting responses toward B. longum, and significant and strong growth- promoting response toward B. bifidum was observed in extracts of Actinidia arguta, Allium cepa, A. sativum, Brassica campestris subsp. napus vats. pekinensis, Capsicum frutescens, Daucus carota var. sativa, L sativa, 1. esculentum and L. esculentum var. cerasforme, Nelumbo nucifera, Cucurbita moschata, Lackca sativa var. capitata, and Rubus coreanus. For L casei, extracts of A. fshlosum, A. hberosum, Cichorium intbus, Cucurbita moschat\ulcorner Ipomoea batatas, 1. sativa var. capitata, L. esculentum, P. brachycarpa, Raphanus sativus, R. coreanus, and S. melongena strongly enhanced the growth of this bacteria. In modified Gy rgy broth, the promoting effect was most pronounced with B. bifidum and L. casei among lactic acid bacteria used. In MRS broth, A. arguta, A. cepa, A. sativum, B. campestris subsp. napus var. pekinensis, C. frutescens, and D. carota var. sativa L. satiw var. capitata, and R. coreanus strongly enhanced the growth of B. bifidum, Growth of B. longum was strongly affected by the addition of extracts from L. sativa var. capitata. For L casei, moderate growth-promoting responses were observed in 9 vegetable extracts. The promoting effect in MRS broth was most pronounced with B. bifidum among lactic acid bacteria used.