• Title/Summary/Keyword: Acid Resistance

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Cholesterol Lowering Effect of Lactobacillus plantarum Isolated from Human Feces

  • Ha Chul-Gyu;Cho Jin-Kook;Lee Chi-Ho;Chai Young-Gyu;Ha Young-Ae;Shin Shang-Hun
    • Journal of Microbiology and Biotechnology
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    • v.16 no.8
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    • pp.1201-1209
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    • 2006
  • The purpose of this study was to isolate probiotic lactic acid bacteria (LAB) that produce bile salt hydrolase (BSH), and to evaluate its effects on serum cholesterol level. One-hundred-twenty bacterial colonies were initially isolated from human feces, and five strains were selected after screening based on their resistance to acids, tolerance against bile salts, and inhibitory activity on Escherichia coli. The Lactobacillus plantarum strain with the highest level of BSH activity was identified using 16S rRNA sequences, and was named L. plantarum CK 102. L. plantarum CK 102 at a level of 1.36$\times$10$^8$cfu/ml survived in pH 2 buffer for 6 h and exhibited excellent tolerance for bile salt. Coculturing the strain with E. coli in MRS broth resulted in strong inhibition against growth of E. coli at 18 h. Furthermore, the potential effect of CK 102 on serum cholesterol level was evaluated in rats. Thirty-two rats [Sprague-Dawley (SD) male, 129$\pm$l g, 5 weeks old] were divided into four groups of eight each. For six weeks, Group 1 was fed a normal diet (negative control); Group 2 was fed a cholesterol-enriched diet (positive control); Group 3 was fed a cholesterol-enriched diet plus L. plantarum CK 102 at 1.0$\times$10$^7$cfu/ml; and Group 4 was fed a cholesterol-enriched diet plus L. plantarum CK 102 at 5.0$\times$10$^7$cfu/ml. Blood samples were collected, serum lipids were analyzed, and weights of the organs were measured. Total blood cholesterol level, triglyceride, LDL-cholesterol, and free-cholesterol values were lower in rats that were fed 1. plantarum CK 102 than in those not fed L. plantarum CK 102. This cholesterol lowering effect implies that L. plantarum CK 102 could be utilized as an additive for health-assistance foods. In conclusion, these results suggest that the 1. plantarum CK 102 isolated could be used commercially as a probiotic.

Inhibitory Activity of Garlic Fermented by Pediococcus pentosaceus KACC 91419 against Antibiotic-resistant Pathogens

  • Ham, Jun-Sang;Lee, Seung-Gyu;Kim, Min-Kyung;Oh, Mi-Hwa;Jeong, Seok-Geun;Kim, Dong-Hun;Lee, Se-Hyung;Chae, Jong-Pyo;Lee, Ji-Yoon;Kang, Dae-Kyung
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.9
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    • pp.1236-1243
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    • 2010
  • The aim of this study was to screen lactic acid bacteria for the fermentation of garlic and to assess the increase in inhibitory activity of garlic fermented against antibiotic-resistant pathogens for use as an animal feed supplement. We screened 45 strains of lactobacillus for the fermentation of garlic. Of these strains, 23 showed similar growth rates with or without allicin. Cultures of the 23 strains were mixed with an equivalent amount of garlic juice and incubated overnight at $37^{\circ}C$. The three strains with the lowest pH values were Lactobacillus paracasei KCTC 3169, L5 strain, and L. reuteri SW. Garlic juice fermented by the L5 strain more strongly inhibited antibiotic-resistant pathogenic bacteria than L. paracasei KCTC 3169, L. reuteri SW, or garlic juice itself. By examining carbohydrate utilization, morphologic properties and 16S rRNA gene sequences, we identified the L5 strain as Pediococcus pentosaceus and deposited it in the name of P. pentosaceus KACC 91419 into the Korea Agricultural Culture Collection. To identify the antimicrobial compound from the garlic filtrate fermented by P. pentosaceus KACC 91419, we fractionated P. pentosaceus KACC 91419 culture on a C18 column and checked the antimicrobial activity of fractions A6 to A10. Only fraction A9 showed inhibitory activity on Staphylococcus aureus. Comparing the mass spectra of the fractions with and without antimicrobial activity, we observed a single dominant product ion (m/z 157.99) from the fraction showing antimicrobial activity. Its molecular mass (157.99) was 2 atomic mass units less than that of allicin (162.02). This suggests that allicin might be converted to its derivative, which has antimicrobial activity, during fermentation by P. pentosaceus KACC 91419.

Comparison of Forage Production of Annual Legume in the Central Region of Korea (중부지방에서 일년생 콩과목초의 사초 생산성 비교)

  • Kim, J.D.;Kwon, C.H.;Kim, S.G.;Park, H.S.;Ko, H.J.;Kim, D.A.
    • Journal of Animal Science and Technology
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    • v.44 no.5
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    • pp.617-624
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    • 2002
  • Annual legume is being used as an important source of protein for farm animals and an ingredient for nitrogen fertilizers. There are, however, difficulties in selecting appropriate cultivar and forage management technique. The objective of this study is to select the best performing cultivars and evaluate a forage value on annual legume at two locations (Suwon and Sunghwan) for 1 year (1999${\sim}$2000). All cultivars shown a seedling vigor and lodging resistance of 8 rating or higher. Crimson and rose clover showed that they are appropriate for overwintering, but ;Laser; (35.9%) and 'Nitro'(9.1%) of persian clover variety did not overwinter well from 1999 to 2000. Flower stage was observed 4th of May for 'Tibbee', 6th of May for 'Contea' crimson clover, and 29th of April for 'Bolta balansa' rose clover. DM yield of a crimson clover 'Contea' (4,218kg/ha) was the highest among the legume forage. A crimson clover 'Tibbee' and rose clover 'Bolta balansa' also had a high production yield (3,874 and 3,828kg/ha). Calculations of relative feed value (RFV) based on the acid and neutral detergent fiber (ADF and NDF) of annual legume were over 125, which means that quality was high. According to the results of this study, crimson and rose clovers are recommended due to their high winter survival rate and high DM yield. Persian clover is not recommended because of a low overwintering rate at the Central region in Korea.

Removal of Cd(II) by Cation Exchange Resin in Differential Bed Reactor (미분층반응기에서 양이온 교환수지에 의한 카드뮴(II)의 제거)

  • Kim, Jong-Tae;Chung, Jaygwan G.
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.7
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    • pp.1193-1203
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    • 2000
  • In this study, in order to remove Cd(II) from aqueous solutions, strongly acidic cation exchange resin(SK1B) by Diaion Co. was employed as an adsorbent. Experiments were mainly performed in two parts at room temperature($25{\pm}5^{\circ}C$) : batch tests and adsorption kinetics tests. In batch tests adsorption equilibrium time, pH effects, temperature effects, several adsorption isotherms, and finally desorption tests were examined. In differential bed tests, an optimum flow rate and an overall adsorption rate were obtained. In the batch experiment, adsorption capability increased with pH and became constant above pH 6 and adsorption quantity increased with temperature. Batch experimental data found that Freundlich and Sips adsorption isotherms were more favorable than Langmuir adsorption isotherm over the range of concentration (5~15ppm). The desorbent used in the desorption test was hydrochloric acid solution with different concentrations(0.01~2N). The degree of regeneration increased with concentration of desorbent and decreased slightly with the number of regeneration. In the continuous flow process using a differential bed reactor, the optimum flow rate was $564m{\ell}/min$ above which the film diffusion resistance was minimized. The overall adsorption rate for the removal of Cd(II) by cation exchange resin was found as follows ; $r=1.3785C_{fc}^{1.2421}-2.0907{\times}10^{0.0746C_i}\;q_e^{0.0121C_i-0.0301}$

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Isolation and characterization of a Bacillus spp. for manufacturing the feed additives in livestock (가축의 보조사료 개발을 위한 Bacillus spp.의 분리 및 특성)

  • Park, Hae Suk;Jo, Seung Wha;Yim, Eun Jung;Kim, Yun Sun;Moon, Sung Hyun;Cho, Ho Seong;Kim, Hyun-Young;Cho, Yong Sik;Cho, Sung Ho
    • Korean Journal of Microbiology
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    • v.51 no.4
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    • pp.419-426
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    • 2015
  • The aims of this study were to isolate spore-forming Bacillus strains that exhibit high digestibility and anti-pathogenic bacteria toward feed for calves. Total 136 spore-forming strains were isolated from finished feeds and their ingredients. Among them, 93 strains were identified as Bacillus species when analyzed by 16S rRNA sequencing. For industrial use, three strains named as Bacillus licheniformis SHS14, B. subtilis LCB7, B. amyloliquefaciens LCB10 were selected after evaluating the industrial standards that are related with heat and acid resistance, enzyme activities, and anti-pathogenic activities against Samonella dublin ATCC15480 and E. coli K99. After each culture, 3 selected strains were mixed together at 1:1:1 (v/v/v) ratio and then prepared as the mixed starter culture for feeding. The changes in microbial community were analyzed via 16S rRNA metagenomics. The initial community ratio among three strains was maintained even after manufacturing into final products. Also, in vitro, enzymatic and anti-pathogenic activities were almost same as those when cultured in single culture, and results of anti-pathogenic activities conducted with calves showed 90% activities against lincomycin, which would be indicative of a promising feed starter.

Effects of Pulsed Nd:YAG Laser Irradiation and Fluoride Compound Applicatin on Acid Resistance of Bovine Teeth (Pulsed Nd:YAG 레이저 조사와 불소화합물 도포가 치아 내산성에 미치는 영향)

  • An-Hee Lee;Woo-Cheon Kee
    • Journal of Oral Medicine and Pain
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    • v.20 no.2
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    • pp.429-447
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    • 1995
  • This study was designed to determine the most effective concentration of fluoride and levels of laser irradiation for the remineralization of decayed teeth. After irradiation with a pulsed Nd:YAG laser and the topical application of fluoride, phosphate and fluoride concentration in enamel were measured. And then the changes on surface enamel using an scanning electron microscope were observed. Samples by extraction healthy, permanent, mandibular bovine teeth with no caries were obtained. Among them 371 healthy samples were selected and artificial carious lesions were made. 20 samples were assigned to each experimental group. After irradiation with a pulsed Nd:YAG laser with total energy densities of 10J/$\textrm{cm}^2$, 20J/$\textrm{cm}^2$ for each group. On the teeth, 2% NaF, 1.9% NH4F, 1.6% TiF4 Elmex gel(amine fluoride) and 1.23% APF gel were applied. After pH circulatory procedures, concentrations of fluoride with and Ionalyzer (Orion Research, Model 901, USA) and phosphates with an Uv/V is spectrophotometer (Uvikon 860, Kontrom Co, Switzerland) were measured. By etching the teeth in layers and measuring fluoride concentrations, a profile of fluoride penetration according to depth could be developed. And also the changes on the surface of the enamel using an electron scanning microscope were observed. The comparative analysis yielded the following results : 1. Phosphate concentration was low in all groups compared with the control group except for teeth treated Elmex gel, irradiated with 10J/$\textrm{cm}^2$ and 30J/$\textrm{cm}^2$ energy densities. Teeth treated with APF gel and 30J/$\textrm{cm}^2$ irradiation gad the lowest phosphate concentration. 2. Among all groups, fluoride concentrations in tooth enamel were highest in APF gel and NaF groups irradiated at 30J/$\textrm{cm}^2$. The APF gel group had the highest fluoride concentrations across all energy densities. 3. In the APF gel group, and the NaF group, the greater the energy density of the laser, the higher the fluoride concentrations in the enamel. 4. In all groups, the concentration of fluoride in the enamel by depth tended to decrease with depth. 5. Under the scanning electron microscope, under the condition of irradiation with 20J/$\textrm{cm}^2$, enamel crack was detected for the first time. In the NH4F group, spherical deposits were found on the surface of the enamel, and in the TiF4 group the surface of enamel was covered with an irregular, thin membranous mass in places. In the APF gel and NaF groups irradiated with 10J/$\textrm{cm}^2$, spherical and irregular particles covered the teeth. When these groups were irradiated at 20J/cm2, they were covered with amorphous crystals. These results suggest that one could obtain more effective anticariogenic effects without damage to teeth when less than 20J/$\textrm{cm}^2$ energy densities and APF gel are used.

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Fabrication Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF)/Ce0.9Gd0.1O2−δ (GDC) and La0.6Ba0.4Co0.2Fe0.8O3−δ (LBCF)/Ce0.9Gd0.1O2−δ (GDC) Composite Cathodes for Intermediate Temperature Solid Oxide Fuel Cells (중저온 SOFC용 Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF)/Ce0.9Gd0.1O2−δ (GDC) 및 La0.6Ba0.4Co0.2Fe0.8O3−δ (LBCF)/Ce0.9Gd0.1O2−δ (GDC) 복합체 양극 제조)

  • Lee, Seung-Hun;Yoon, Song-Seol;Cha, Young-Chul;Lee, Jun;Hwang, Hae-Jin;Moon, Ji-Woong
    • Journal of the Korean Ceramic Society
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    • v.44 no.12
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    • pp.740-746
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    • 2007
  • The potential candidates for IT-SOFCs cathode materials, $Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-{\delta}}$ (BSCF) and $La_{0.6}Ba_{0.4}Co_{0.2}Fe_{0.8}O_{3-{\delta}}$ (LBCF) powders, were synthesized by a EDTA-citrate combined method from $Sr(NO_3)_2$, $Ba(NO_3)_2$, $La(NO_3)_3{\cdot}6H_2O$, $Co(NO_3)_2{\cdot}6H_2O$, $Fe(NO_3)_3{\cdot}9H_2O$, citric acid and $EDTA-NH_3$. The cathode performance of symmetrical electrochemical cells consisting of BSCF-GDC or LBCF-GDC composite electrodes and a GDC electrolyte was investigated using by AC impedance spectroscopy at the temperature range of 500 to $700^{\circ}C$. It was found that a single phase perovskite could be successfully synthesized when the precursor is heated at $850^{\circ}C$ for 2 h. Due to thermal expansion mismatch between BSCF and GDC, the composite cathodes with lower GDC content than 45 wt% were peeled off from the GDC electrolyte and their electrode polarization resistance was estimated to be high. The thermal expansion coefficient of BSCF-GDC composites was decreased with increasing the GDC content and the electrode peeling off did not occur in BSCF-45 and 55 wt% GDC composites. BSCF-45 wt% GDC composite electrode showed the lowest area specific resistances (ASR) of 0.15 and $0.04{\Omega}{\cdot}cm^2$ at 600 and $700^{\circ}C$, respectively. On the other hand, LBCF-GDC composite cathodes showed higher ASR than the BSCF-45 and 55 wt% GDC and their cathode performance were decreased with the GDC content.

Mix Design Conditions at Early Curing Age of PCS-Coating Material Effected on Improvement in Bond Strength of Coated Rebar (도장철근의 부착강도 개선에 영향을 미치는 초기재령에서의 PCS 도장재 배합조건)

  • Jo, Young-Kug;Park, Dong-Yeol;Kim, Wan-Ki
    • Journal of the Korea Concrete Institute
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    • v.25 no.1
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    • pp.73-80
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    • 2013
  • Polymer cement slurry (PCS) made from organic polymer dispersion and cement has good adhesion to steel, waterproofness and acid resistance due to being of polymer films formed in cement slurry. The purpose of this study is to evaluate the mix design conditions at early curing age of PCS-coating material effected on improvement in bond strength of coated rebar. The test pieces are prepared with two types of polymer dispersions such as St/BA and EVA, four polymer-cement ratios, two types of cement, four coating thicknesses and three curing ages, and tested for the bond strength test. From the test results, in general, bond strength of PCS-coated rebar is better than that of uncoated rebar and epoxy-coated rebar. It is also high bond strength at curing ages of 7-day or less, and coating thicknesses of $75{\mu}m$ and $100{\mu}m$. The maximum bond strength of PCS-coated rebar at curing age of 3-hour is almost same as that of curing age of 1-day and 7-day. The maximum bond strength of PCS-coated rebar with ultra high-early strength cement and St/BA at polymer-cement ratio of 80%, and coating thickness of $100{\mu}m$ is about 1.52 and 1.58 times respectively, the strength of uncoated rebar and epoxy-coated rebar. It is apparent that the curing age, coating thickness, type of polymer and cement are very important factors to improve the bond strength of PCS-coated rebar to cement concrete. We can have basic information that PCS-coated rebar with curing age at 3-hour and coating thickness of $100{\mu}m$ can replace epoxy-coated rebar.

Lipid accumulation product is a predictor of nonalcoholic fatty liver disease in childhood obesity

  • Ozcabi, Bahar;Demirhan, Salih;Akyol, Mesut;Akay, Hatice Ozturkmen;Guven, Ayla
    • Clinical and Experimental Pediatrics
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    • v.62 no.12
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    • pp.450-455
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    • 2019
  • Background: Lipid accumulation product (LAP) is associated with the presence and severity of nonalcoholic fatty liver disease (NAFLD) in adults. Purpose: Here we evaluated the ability of LAP to predict NAFLD in obese children. Methods: Eighty obese children (38 girls; age 6-18 years) were included. Anthropometric measurements and biochemical values were obtained from the patients' medical records. LAP was calculated as [waist circumference (WC) (cm) - 58]×triglycerides (mmol/L) in girls; [WC (cm) - 65]×triglycerides (mmol/L) in boys. The minLAP and adjLAP were described (3% and 50% of WC values, respectively) and the total/high-density lipoprotein cholesterol index (TC/HDL-C) was calculated. NAFLD was observed on ultrasound, and patients were divided into 3 groups by steatosis grade (normal, grade 0; mild, grade 1; moderate-severe, grade 2-3). The area under the curve (AUC) and appropriate index cutoff points were calculated by receiver operator characteristic analysis. Results: LAP was positively correlated with puberty stage (rho=0.409; P<0.001), fasting insulin (rho= 0.507; P<0.001), homeostasis model assessment of insulin resistance (rho=0.470; P<0.001), uric acid (rho=0.522; P<0.001), and TC/HDL-C (rho=0.494; P<0.001) and negatively correlated with HDL-C (rho=-3.833; P<0.001). LAP values could be used to diagnose hepatosteatosis (AUC=0.698; P=0.002). The LAP, adjLAP, and minLAP cutoff values were 42.7 (P=0.002), 40.05 (P=0.003), and 53.47 (P= 0.08), respectively. For LAP, the differences between the normal and mild groups (P=0.035) and the normal and moderate-severe groups were statistically significant (P=0.037), whereas the difference between the mild and moderate-severe groups was not (P>0.005). There was a statistically significant difference between the normal and mild groups for adjLAP (P=0.043) but not between the other groups (P>0.005). There was no significant intergroup difference in minLAP (P>0.005). Conclusion: LAP is a powerful and easy tool to predict NAFLD in childhood. If LAP is ≥42.7, NAFLD should be suspected. This is the first study to assess LAP diagnostic accuracy for childhood obesity.

Clinical Manifestation of Extrapulmonary Tuberculosis in Children : A Single Center Experience (단일기관에서 경험한 소아 폐외결핵의 임상적 고찰)

  • Seung, So Jin;Kwak, Ga Young;Lee, Soo Young;Kang, Jin Han
    • Pediatric Infection and Vaccine
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    • v.15 no.2
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    • pp.167-173
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    • 2008
  • Purpose : We evaluated the prevalence and clinical, microbiological features of extrapulmonary tuberculosis (EPT) in pediatric patients. Methods : We retrospectively reviewed medical records of pediatric patients diagnosed with EPT at The Catholic University of Korea, Incheon St. Mary's Hospital between 2000 and 2007. Results : Of 109 patients diagnosed with tuberculosis (TB), 12 patients (11%) were admitted with EPT. At 2006-2007, the proportion of patients with EPT among patients with TB was the highest (20%) comparing with last 6 years. The ratio of male to female patients was 1.4:1 and the mean age was 9.2 years (range, 3 months-15 years). The involved sites were pleura in 5 (41.6%), central nervous system in 3 (25%), miliary TB in 2 (16.7%), gastrointestinal tract in 1 (8.3%) and bone and joint in 1 (8.3%). The most common symptom at admission was fever (91.6%) and mean duration of fever was 15.8 days (range, 0-47 days) in spite of the proper treatment. Confirmed rate for acid fast bacillus stain, culture, and polymerase chain reaction were 33.3%, 41.6% and 41.6%. Of 5 culture proven cases, 4 (80%) were resistant to more than one antituberculosis drugs. Eleven patients recovered without complication and 1 patient died. Conclusion : Total incidence of TB decreased steadily according to the nationwide survey. However, our results suggest that the proportion of diagnosis with EPT among diagnosis with TB in children has increased. Microbiological diagnosis of EPT in children was more difficult than that of pulmonary TB. And drug resistance rate has increased.

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