• Journal of Dairy Science and Biotechnology
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• v.37 no.2
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• pp.129-135
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• 2019

This study investigated the effects of heat-treated and non-heat-treated bovine lactoferrin on the growth of Lactococcus lactis subsp. cremoris JCM 20076. The addition of heat-treated and non-heat-treated bovine lactoferrin in adjusted MRS medium stimulated the growth of Lc. cremoris JCM 20076. Heat-treated bovine lactoferrin had a greater impact on the growth of Lc. cremoris JCM 20076 compared to that with non-heat-treated bovine lactoferrin. Bovine lactoferrin heated at $65^{\circ}C$ for 30 min stimulated the growth of the bacteria more than that heated at $80^{\circ}C$ for 5 min. Furthermore, the growth of Lc. cremoris JCM 20076 increased substantially with heat-treated bovine lactoferrin at a concentration of 1 mg/mL.

• Journal of Microbiology and Biotechnology
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• v.18 no.4
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• pp.773-777
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• 2008

Phosphate solubilizing bacteria (PSB) were isolated from the rhizosphere of Chinese cabbage and screened on the basis of their solubilization of inorganic tricalcium phosphate in liquid cultures. Ten strains that had higher solubilization potential were selected, and they also produced indole-3-acetic acid, 1-aminocyclopropane-1-carboxylate (ACC) deaminase, and siderophores. The strains were identified to be members of Pseudomonas, by 16S rDNA sequence analysis. Seed bacterization with PSB strains increased the root elongation and biomass of Chinese cabbage in seedling culture, although they had no effect on phosphorus uptake of plants. The plant growth promotion by PSB in this study could be due to the production of phytohormones or mechanisms other than phosphate solubilization, since they had no effect on P nutrition.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.398-401
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• 2003

Azo dyes are aromatic compounds characterized by one or more azo bonds $(R_l-N=N-R_2)$. More than 800,000 tons of dyes are produced annually worldwide, of which 60-70% are azo dyes. During manufacturing, an estimated 10-15% is released into the environment. Aside from their negative aesthetic effects, certain azo dyes have been shown to be toxic and, in some cases, these compounds are carcinogenic and mutagenic. To establish biological wastewater treatment of azo dye, it is essential to discover azo dye-degrading microorganisms. In this report, sludge-contaminated with dyes were gathered through wastewater outlets from the industrial regions. The following to separation of bacteria within them, bacteria which decolorize methyl red, a azo dye, were selected and destined.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.737-740
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• 2000

Two groups of bacteria, harmful and useful bacteria, coexist in our body. Harmful bacteria and free radicals which cause many diseases and agings could be controlled by not synthetic materials but natural products. 50 kinds of natural products were searched for this purpose, some of them expressed bacterial controlling ability. Clostridium difficle was controlled by Paeonia Japonica and Lycii Fructus, etc., Clostridium perfringens was inhibited by Scutellaria Baicalensis and Astragali Radix, etc., and same way, Listeria monocytogenes; Paeonia Japonica and Scutellaria Baicalensis, E. coli; Scutellaria Baicalensis and Schizandrae Fructus, Staphylococcus aureus; Paeonla Japonica and Scutellaria Baicalensis, Streptococcus mutans; Coptis Rhizoma, respectively. These natural products will play an important role in bio-Industry.

• The Korean Journal of Food And Nutrition
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• v.12 no.6
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• pp.569-574
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• 1999

Response surface methodology(RSM) was applied to determine the optimum heating conditions(tem-perature and time) for the inactivation of bacteria associated with food hygiene. Coefficients of determinations(R2) for the cell growth were 0.9155(P<0.05) in Pseudomonas aeruginosa 0.8997(P<0.05) in Escherichia coli 0.9690(P<0.01) in Salmonella typhimurium 0.9393(P<0.05) in Enterobacter aerogenes and 0.7905 in Vibrio parahaemolyticus. The growth of strains was significantly affected by the temperature and time and reaction to temperature was most closely correlated to the inhibition of growth. On the basis of superimposed contour maps of cell growth the optimum range of heating conditions were 55.62-6$0^{\circ}C$ and 19.25-30 min.

• Korean Journal of Microbiology
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• v.10 no.1
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• pp.1-8
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• 1972

This experiment was carried out to investigate the physiological characteristics of isolated bacteria, Ferrobacillus ferooxidans from copper mine water in Korea. The results obtained were as follows ; 1. The optimum pH range for the growth of these bacteria was 2.0-3.0 and optimum temperature was $20^{\circ}C$-$30^{\circ}C$. 2. The oxidation curves of ferrous iron to the ferric iron ran parallel with the growth curves. 3. The optimum nitrogen concentration was 400-800 ppm and the minimal flow rate of air for the maximal growth of the bactria was 70 ml air/min./200ml medium. 4. The growth of these bacteria was inhibited by the absence of ferrous iron and by the addition of sulfur. 5. Ferrous iron at a concentration of 9000 ppm, appeared to be optimum for the most rapid growth of Ferrobacillus ferrooxidans.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.811-813
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• 2008

To see the effect of magnesium on adhesion to natural zeolites, a series of batch tests were performed in this research. Mixed bacteria were sampled from the digestion tank at a local sewage treatment plant in Seoul. Magnesium-zeolites were synthesized by mixing natural zeolites with 0.096 M, 0.24 M, and 0.48 M of MgCl2 solution. For comparison, manganese and trivalent ferric zeolites were also prepared. Two grams of 0.2 mm $\sim$ 0.3 mm sized zeolites(non-treated, Mg, Mn and Fe(III) treated zeolites) and 20 mL of water were mixed in a Corex 25 mL tube. Five milliliters of culture solution including bacteria was added to the tube. The tubes were equilibrated in a shaking incubator at mesophilic temperature $(30{\pm}2^{\circ}C)$. The bacterial concentrations were measured with a Microluminometer (New Horizons 3550i) and total organic carbon (TOC) spectrophotometer (Multi NC-3100).

• Journal of Marine Life Science
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• v.4 no.1
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• pp.22-28
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• 2019

The bacterial diversity of an Antarctic hard coral, Errina fissurata, was examined by isolating bacterial colonies from crushed coral tissue and by sequencing their 16S rRNA gene. From the analyzed results, the bacteria were classified as Actinobacteria (56%), Firmicutes (35%) and Proteobacteria (9%). The thirty-four isolates were cultured in liquid media at different temperatures and their growth was assessed over time. The majority of the isolates displayed their highest growth rate at 25℃ during the first three days of cultivation, even though the coral was from a cold environment. Nevertheless, strains showing their highest growth rate at low temperatures (15℃ and 4℃) were also found. This study reports the composition of an Antarctic hard coral-associated culturable bacterial community and their growth behavior at different temperatures.

• Food Science and Biotechnology
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• v.14 no.4
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• pp.503-508
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• 2005

Screening for antilisterial activity was performed in about three thousand isolates of lactic acid bacteria (LAB) from Chinese cabbage kimchi, and finally based on the relatively stronger antilisterial activities eight bacterial strains were selected. The bacteria were further characterized in terms of their tolerance to artificial gastric juice, pH 2.5, bile salts (0.3% oxgall), and to the different NaCl concentrations. Of the isolates, YK005 was especially investigated for its physiological characteristics due to its inhibitory activity against gram-positive Listeria monocytogenes as well as gram-negative Escherichia coli O157:H7, as they have been constantly reported to be resistant against bacteriocins produced by a number of LAB strains. YK005 was found to be rod-shaped, $3.8\;{\mu}m$ long ${\times}\;0.5\;{\mu}m$ wide, non-sporeforming, non-motile, catalase-negative, and produced gas from glucose (heterolactic). Based on the biochemical data obtained by API 50 CHL medium, the isolate was tentatively identified as Lactobacillus brevis. To validate the result obtained by the biochemical identification, rRNA-based PCR experiments using a pair of species-specific primers for L. brevis were conducted and a single band of 1400 bp was observed, which strongly indicated that YK005 belongs to L. brevis. The LAB isolates are potentially exploited as human probiotic organisms and are employed to control some food-borne pathogens like L. monocytogenes.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.9
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• pp.1276-1281
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• 2013

An in vitro experiment was conducted to evaluate the effect of methylcellulose on the attachment of major cellulolytic bacteria on rice straw and its digestibility. Rice straw was incubated with ruminal mixture with or without 0.1% methylcellulose (MC). The attachment of F. succinogenes, R. flavefaciens and R. albus populations on rice straw was measured using real-time PCR with specific primer sets. Methylcellulose at the level of 0.1% decreased the attachment of all three major cellulolytic bacteria. In particular, MC treatment reduced (p<0.05) attachment of F. succinogenes on rice straw after 10 min of incubation while a significant reduction (p<0.05) in attachment was not observed until 4 h incubation in the case of R. flavefaciens and R. albus. This result indicated F. succinogenes responded to MC more sensitively and earlier than R. flavefaciens and R. albus. Dry matter digestibility of rice straw was subsequently inhibited by 0.1% MC, and there was a significant difference between control and MC treatment (p<0.05). Incubated cultures containing MC had higher pH and lower gas production than controls. Current data clearly indicated that the attachment of F. succinogenes, R. flavefaciens and R. albus on rice straw was inhibited by MC, which apparently reduced rice straw digestion.