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Identification and Characterization of Lactobacillus salivarius subsp. salivarius from Korean Feces

  • Bae, Hyoung-Churl
    • Proceedings of the Korean Society for Food Science of Animal Resources Conference
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    • 2004.05a
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    • pp.89-119
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    • 2004
  • This study was conducted to isolate lactobacilli having probiotic characteristics to be used as health adjuncts with fermented milk products. Acid tolerant strains were selected in Lactobacilli MRS broth adjusted to pH 4.0 from 80 healthy persons (infants, children and adults). And bile tolerant strains were examined in Lactobacilli MRS broth in which 1.0% bile salt was added. By estimation above characteristics, the strains No. 27, which was isolated from adult feces, was selected and identified as Lactobacillus salivarius subsp. salivarius based on carbohydrate fermentation and 16S rDNA sequencing. It was used as a probiotic strain in fermented milk products. The pH of fermented milk decreased from pH 6.7 to 5.0 and titratable acidity increased from 0.3% to 1.0% by L. salivarius subsp. salivarius (isolation strain 20, 35, and 37), when incubated for 36 h at $37^{\circ}C$. The number of viable cell counts of fermented milk was maximized at this incubation condition. The SDS-PAGE evidenced no significant change of casein but distinct changes of whey protein were observed by isolated L. salivarius subsp. salivarius for titratable acidity being incubated by $0.9{\sim}1.0%$ at $37^{\circ}C$. All of the strains produced 83.43 to 131.96 mM of lactic acid and 5.39 to 26.85 mM of isobutyric acid in fermented products. The in vitro culture experiment was performed to evaluate ability to reduce cholesterol levels and antimicrobial activity in the growth medium. The selected L. salivarius subsp. salivarius reduced $23{\sim}38%$ of cholesterol content in lactobacilli MRS broth during bacterial growth for 24 hours at $37^{\circ}C$. All of the isolated L. salivarius subsp. salivarius had an excellent antibacterial activity with $15{\sim}25$ mm of inhibition zone to E. coli KCTC1039, S. enteritidis KCCM3313, S. typhimurium M-15, and S. typhimurium KCCM40253 when its pH had not been adjusted. Also, all of the isolated L. salivarius subsp. salivarius had partial inhibition zone to E. coli KCTC1039, E. coli KCTC0115 and S. enteritidis KCCM3313 when it had been adjusted to pH 5.7. The selected strains were determined to have resistances of twelve antibiotic. Strains 27 and 35 among the L. salivarius subsp. salivarius showed the highest resistance to the antibiotics. Purified ${\alpha}$-galactosidase was obtained by DEAE-Sephadex A-50 ion exchange chromatography, Mono-Q ion exchange chromatography and HPLC column chromatography from L. salivarius subsp. salivarius 27. The specific activity of the purified enzyme was 8,994 units/mg protein, representing an 17.09 folds purification of the original cell crude extract. The molecular weight of enzyme was identified about 53,000 dalton by 12% SDS-PAGE. Optimal temperature and pH for activity of this enzyme were $40^{\circ}C$ and 7.0 respectively. The enzyme was found to be stable between 25 and $50^{\circ}C$. ${\alpha}$-galactosidase activity was lost rapidly below pH 5.0 and above pH 9.0. This enzyme was liberated galactose from melibiose, raffinose, and stachyose, and also the hydrolysis rate of substrate was compound by HPLC. These results indicated that some of the L. salivarius subsp. salivarius (strain 27 and 35) are considered as effective probiotic strains with a potential for industrial applications, but the further study is needed to establish their use as probiotics in vivo.

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Enhanced biological effect of fermented soy-powder milk with Lactobacillus brevis increasing in γ-aminobutyric acid and isoflavone aglycone contents (가바와 비당체 이소플라본이 증가된 Lactobacillus brevis 발효 콩-분말 두유의 생리활성 증진 효과)

  • Hwang, Chung Eun;Kim, Su Cheol;Lee, Jin Hwan;Hong, Su Young;Cho, Kye Man
    • Journal of Applied Biological Chemistry
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    • v.61 no.3
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    • pp.245-255
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    • 2018
  • The research was aimed to analyze the functional constituents (GABA and isoflavone), radical (2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and hydroxyl) scavenging activities and enzyme (${\alpha}-glucosidase$ and lipase) inhibitory effects of soypowder milk (SPM) and fermented soy-powder milk (FSPM) with varied Lactobacillus brevis. Ten ${\gamma}-aminobutyric$ acid (GABA) producing lactic acid bacteria that showed 96-99% similarity with L. brevis, according to 16S rRNA gene sequence analysis, were isolated from fermented kimchi. The conversion rates of GABA were obtained 66.96-93.51, 63.76-84.58, and 57.05-69.75% in monosodium glutamate, gluten and soy protein, respectively. The levels of pH and glutamic acid of FSPM were found lower than those of SPM, but the acidity and GABA contents were higher. The GABA conversion rate of FSPM with BMK484 strain was attained the highest 69.97%. The contents of isoflavone glycoside ($1290.93{\mu}g/g$) was higher in SPM, but the content of isoflavone aglycone ($287.27-501.9{\mu}g/g$) was higher in FSPM. The levels of isoflavone aglycone such as daidzein, glycitein and genistein, were found as the highest 240.2, 61.24 and $200.45{\mu}g/g$, respectively, when FSPM was made with BMK484 strain. The DPPH, ABTS and hydroxyl radical scavenging and ${\alpha}-glucosidase$ and pancreatic lipase inhibitory activities of FSPM made with BMK484 strain were the relatively higher 60.31, 88.10, 61.25, 52.71, and 39.37%, respectively. Therefore, the L. brevis can be used as a material capable of simultaneously enhanced GABA and isoflavone aglycone in FSPM.

AN EXPERIMENTAL STUDY ON THE RESIDUAL STRESS AND BOND STRENGTH OF CERAMO-METAL SYSTEM (치과도재용(齒科陶材用) 합금(合金)과 도재간(陶材間)의 잔류응력(殘溜應力) 및 결합강도(結合强度)에 관(關)한 실험적(實驗的) 연구(硏究))

  • Kim, Gi-Jin;Bae, Tae-Seong;Song, Kwang-Yeob;Park, Charn-Woon
    • The Journal of Korean Academy of Prosthodontics
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    • v.29 no.2
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    • pp.67-84
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    • 1991
  • This study was carried out to investiagate the residual stress caused by the mismatch of thermal expansion and the bond failure resistance of alloy-porcelain specimens. The thermal expansions of alloys and porcelains were measured by using a straight push-rod dilatometer. Porcelain glass transition temperatures, thermal expansion coefficients, and thermal compatibility indices were derived from length-versus-temperature curves. Strain gauges were used to experimentally determine the Young's moduli of porcelains, the residual stresses of porcelain surface, and tensile bond strengths of the specimens of simulated porcelain metal crown. The obtained results were as follows: 1. The coefficients of thermal expansion for alloys were the minimum of $13.53\mu/^{\circ}C$ and the maximum of $20.11\mu/^{\circ}C$ in the range of $100\sim600^{\circ}C$ and those for porcelains were the minimum of $7.72\mu/^{\circ}C$ and the maximum of $31.24\mu/^{\circ}C$ in the range of $100\sim500^{\circ}C$. 2. The glass transition temperature of porcelains exhibited the same value without my relation to the healing rate, and the thermal disharmony of porcelain and alloy was more affected by porcelains than by the alloys. 3. The Young's moduli of body porcelains were larger than those of opaque porcelains(P<0.01) 4. It seemed that the residual stresses of porcelain surfaces in the porcelainalloy systems were more affected by porcelains than by alleys. 5. The bond strengths of the procelain-base metal alloy systems were larger than those of the porcelain-precious metal alloy systems. The fracture strengths of porcelain surfaces showed significant difference between porcelains (P<0.05).

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Aged Sanroque Mice Spontaneously Develop Sjögren's Syndrome-like Disease

  • Suk San Choi;Eunkyeong Jang;Yeon-Kyung Oh;Kiseok Jang;Mi-La Cho;Sung-Hwan Park;Jeehee Youn
    • IMMUNE NETWORK
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    • v.19 no.1
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    • pp.7.1-7.11
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    • 2019
  • Sjögren's syndrome (SS) is a chronic inflammatory autoimmune disorder that affects mainly salivary and lacrimal glands, but its cause remains largely unknown. Clinical data indicating that SS occurs in a substantial proportion of patients with lupus points to common pathogenic mechanisms underlying the two diseases. To address this idea, we asked whether SS develops in the lupus-prone mouse strain sanroque (SAN). Owing to hyper-activation of follicular helper T (Tfh) cells, female SAN mice developed lupus-like symptoms at approximately 20 wk of age but there were no signs of SS at that time. However, symptoms typical of SS were evident at approximately 40 wk of age, as judged by reduced saliva flow rate, sialadenitis, and IgG deposits in the salivary glands. Increases in serum titers of SS-related autoantibodies and numbers of autoantibody-secreting cells in cervical lymph nodes (LNs) preceded the pathologic manifestations of SS and were accompanied by expansion of Tfh cells and their downstream effector cells. Thus, our results suggest that chronic dysregulation of Tfh cells in salivary gland-draining LNs is sufficient to drive the development of SS in lupus-prone mice.

Bioaugmentation with GFP-Tagged Pseudomonas migulae AN-1 in Aniline-Contaminated Aquifer Microcosms: Cellular Responses, Survival and Effect on Indigenous Bacterial Community

  • Zhao, Yongsheng;Qu, Dan;Zhou, Rui;Ma, Yunge;Wang, Hao;Ren, Hejun
    • Journal of Microbiology and Biotechnology
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    • v.26 no.5
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    • pp.891-899
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    • 2016
  • The recently isolated aniline-degrading bacterium Pseudomonas migulae AN-1 was tagged with green fluorescent protein (GFP) to investigate its bioaugmentation potential against aniline-contaminated groundwater through microcosm experiments. The survival and cellular response of GFP-tagged AN-1 introduced in a lab-scale aquifer corresponded directly with aniline consumption. During the process, the GFP-tagged AN-1 biomass increased from 7.52 × 105 cells/ml to 128 × 105 cells/ml and the degradation rate of aniline was 6.04 mg/l/h. GFP-tagged AN-1 was moderately hydrophobic (41.74%-47.69%) when treated with 20-100 mg/l aniline and exhibited relatively strong hydrophobicity (55.25%-65.78%) when the concentration of aniline was ≥100 mg/l. The membrane permeability of AN-1 increased followed by a rise in aniline below 100 mg/l and was invariable with aniline above 100 mg/l. Pyrosequencing analysis showed that the relative abundance of Proteobacteria (accounted for 99.22% in the non-bioaugmentation samples) changed to 89.23% after bioaugmentation with GFP-tagged AN-1. Actinobacteria increased from 0.29% to 2.01%, whereas the abundance of Firmicutes barely changed. These combined findings demonstrate the feasibility of removing aniline in aquifers by introducing the strain AN-1 and provide valuable information on the changes in the diversity of dominant populations during bioaugmentation.

AN ELECTRON MICROSCOPIC STUDY ON THE EFFECTS OF IRRADIATION ON THE BUCCAL MUCOSA OF RAT (방사선조사가 백서 협점막에 미치는 영향에 관한 전자현미경적 연구)

  • Choi Syng Kyu;Lee Sang Rae
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.17 no.1
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    • pp.7-20
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    • 1987
  • The author studied the acute reaction of cobalt-60 irradiation to buccal mucosa in rats and difference of the effects of single versus fractionated exposure. 195 Sprague Dowley strain rats, weighing about 120gm, were used in this experiment. 3 rats served as controls and the remaining 192 rats were divided into six groups of 32 rats each. Experimental group Ⅰ, Ⅱ, Ⅲ were received a single dose of 15Gy, 16.5Gy, 18Gy and group Ⅳ, Ⅴ, Ⅵ were received two equal sized fractionated dose of 9Gy, 9.75Gy, 10.5Gy at 4 hour intervals, respectively. The experimental groups were irradiated with cobalt-60 teletherapy unit, Picker model 4M 60 (Field size, 12x5 cm, SSD, 50㎝, Dose rate, 222cGy/min, Depth, 1㎝). The animals were sacrificed at 1, 2, 3, 6, 12 hours, 1, 3, 7 days after irradiation and the changes of the irradiated buccal mucosa were observed by electron and light microscopy. The results were as follows: 1. A single exposure was more damaging than fractionated exposure, and as the radiation dose increased, the changes of cell organelles became faster, but the healing of radiation-induced damage in fractionated exposure was faster than in single exposure. 2. The radiation-induced changes of the basal cells were the most prominent in 18Gy-single exposure group, and the least in 18Gy-fractionated exposure group. 3. Electron-microscopically, there appeared nuclear changes, swelling of mitochondria and rough endoplasmic reticulum, decrease of free ribosome, presence of vesicles, widening of intercellular space, and loss of basal lamina. The early remarkable changes were partly loss of nuclear membrane and swelling of mitochondria. 4. Light-microscopically, derangement and pyknosis of basal cells, hydropic changes of spinous cells, enlargement of granular cells, indistinctness of basement membrane, and proliferation of epithelium were observed.

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Fatty Acid and Carotenoid Production by Sporobolomyces ruberrimus when Using Technical Glycerol and Ammonium Sulfate

  • Razavi, Seyed Hadi;Mousavi, Seyed Mohammad;Yeganeh, Hassan Mehrabani;Marc, Ivan
    • Journal of Microbiology and Biotechnology
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    • v.17 no.10
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    • pp.1591-1597
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    • 2007
  • The production of carotenoids, lipid content, and fatty acid composition were all studied in a strain of Sporobolomyces ruberrimus when using different concentrations of technical glycerol as the carbon source and ammonium sulfate as the nitrogen source. The total lipids represented an average of 13% of the dry weight, and the maximum lipids were obtained when using 65.5 g/l technical glycerol (133.63 mg/g). The optimal conditions for fatty acid production were at $27^{\circ}C$ using 20 g of ammonium sulfate and a pH range from 6 to 7, which produced a fatty acid yield of $32.5{\pm}1\;mg/g$, including $1.27{\pm}0.15\;mg$ of linolenic acid (LNA), $7.50{\pm}0.45\;mg$ of linoleic acid (LLA), $5.50{\pm}0.35\;mg$ of palmitic acid (PA), $0.60{\pm}0.03\;mg$ of palmitoleic acid (PAL), $1.28{\pm}0.11\;mg$ of stearic acid (SA), $9.09{\pm}0.22\;mg$ of oleic acid, $2.50{\pm}0.10\;mg$ of erucic acid (EA), and $4.25{\pm}0.20\;mg$ of lignoceric acid (LCA), where the palmitic, oleic, and linoleic acids combined formed about 37% of the total fatty acids. The concentration of total carotenoids was 2.80 mg/g when using 20 g of ammonium sulfate, and consisted of torularhodin (2.70 mg/g) and $\beta$-carotene (0.10 mg/g), at $23^{\circ}C$ and pH 6. However, the highest amount with the maximum specific growth rate was obtained (${\mu}_{max}=0.096\;h^{-1}$) with an ammonium sulfate concentration of 30 g/l.

Nutritional Evaluation of Full-fat Sunflower Seed for Broiler Chickens

  • Salari, Somayyeh;Nassiri Moghaddam, H.;Arshami, J.;Golian, A.
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.4
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    • pp.557-564
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    • 2009
  • Two experiments were conducted to evaluate the use of various levels of full-fat sunflower seeds (FFSS) on broiler performance and carcass characteristics. In the first experiment, FFSS was included in a basal diet at 70, 140, and 210 g/kg and the $AME_n$ values of the experimental diets were determined. The linear regression equation of $AME_n$ values on rate of inclusion was calculated. Extrapolation value for the $AME_n$ of FFSS at 100% inclusion was 14.22 MJ/kg. In the second experiment, diets containing various levels (0, 70, 140, and 210 g/kg) of FFSS were given to broilers (Ross strain) from 0 to 49 d. At 28 days of age, blood parameters and digestive enzyme activities were determined and carcass parameters were evaluated at 49 days of age. Weight gain, feed intake and feed conversion ratio (FCR) were improved (p<0.05) when broilers were fed various levels of FFSS in the starter and finisher diets. Breast, thigh, gastrointestinal tract and gizzard weight percentages were not affected by dietary treatments; however, liver weight percentage was decreased significantly (p<0.05) and weight of abdominal fat decreased but this effect was not significant. The activities of digestive enzyme (protease and ${\alpha}$-amylase) were not influenced by the treatments. Activity of alkaline phosphatase, concentrations of calcium, phosphorus, glucose, triglyceride, protein, high density lipoprotein (HDL) and low density lipoprotein (LDL) were not affected by incorporation of FFSS in the broiler diet. Although concentration of HDL increased and LDL decreased, these effects were not significant. The results of this study indicate that FFSS can be used at up to 21% in broiler diets without adverse effects on performance or other parameters of chickens.

EFFECTS OF EARLY FEED RESTRICTION ON GROWTH PERFORMANCE AND BODY COMPOSITION IN BROILERS

  • Santoso, U.;Tanaka, K.;Ohtani, S.;Youn, B.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.6 no.3
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    • pp.401-410
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    • 1993
  • Day-old male and female broilers obtained from commercial strain (Hubbard) were used in this study. At 7 days of age, all chicks were weighed individually (female 0.11 kg and male 0.12 kg in average) and divided into 5 group of 45 birds each group with no replicate in each treatment group as follows: 1. fed ad libitum; 2. fed 75% ad libitum; 3. fed 65% ad libitum; 4. fed 55% ad libitum; 5. fed 45% ad libitum. Chicks were restricted for 10 days (d 7 through 17) of a 56-day trial. Chicks were fed a commercial starter diet (crude protein (CP) 23.8% and metabolizable energy (ME) 3,070 kcal/kg) for 21 days, and commercial finisher diet (CP 20% and ME 3,160 kcal/kg) from 22 to 56 days of age. When chicks were feed-restricted at an early age, compensatory growth did not immediately occur following refeeding. Body weights of restricted chicks were not equal to the ad libitum chicks before 49 days of age. At 56 dyas of age, body weights of restricted chicks were heavier (p<0.01). Abdominal fat values of female chicks fed ad libitum was not significantly different from those fed 45% to 75% ad libitum. Carcass fat values of restricted female chicks were lower than those of control chicks when female chicks were fed either 55% or 45% ad libitum. Furthermore, feed efficiencies of restricted chicks were better. The response of chicks to early feed restriction might depend on the degree of feed restriction, and sex. Factors contributing carcass fat included energy loss, fat protein ratio of carcass, fatty acid synthesis in the liver and triglyceride content of the liver. The heavier body weights in the restricted chicks might be correlated with the lower growth rate during period of feed restriction.

A Study on the Reduction of Gossypol Levels by Mixed Culture Solid Substrate Fermentation of Cottonseed Meal

  • Zhang, Wenju;Xu, Zirong;Sun, Jianyi;Yang, Xia
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.9
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    • pp.1314-1321
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    • 2006
  • The objective of this work was to study the effect of mixed culture solid substrate fermentation of C. tropicalis ZD-3 with A. niger ZD-8 on detoxification of cottonseed meal (CSM), and to investigate the effect of fermentation period, proportion of CSM in substrate, sodium carbonate, minerals and heat treatment on the reduction of free gossypol levels during mixed culture solid substrate fermentation of CSM. Experiment 1: Three groups of disinfected CSM substrate were incubated for 48 h after inoculation with either of the fungi C. tropicalis ZD-3, A. niger ZD-8 or mixed culture (C. tropicalis ZD-3 with A. niger ZD-8). One non-inoculated group was used as the control. Levels of initial and final free gossypol (FG), CP and in vitro CP digestibility were assayed. The results indicated that mixed culture fermentation was far more effective than single strain fermentation, which not only had higher detoxification rate, but also had higher CP content and in vitro digestibility. Experiment 2: CSM substrates were treated according to experimental variables including fermentation period, proportion of CSM in substrate, sodium carbonate, minerals and heat treatment, Then, the treated CSM substrates were inoculated with mixed culture (C. tropicalis ZD-3 with A. niger ZD-8) and incubated at $30^{\circ}C$ for 36 h in a 95% relative humidity chamber. After fermentation ended, FG and CP content of fermented CSM substrate was assayed. The results showed that the appropriate fermentation period was 36 h, and the optimal proportion of CSM in substrate was 70%. Addition of sodium carbonate to CSM substrate was beneficial for fermentative detoxification. Heat treatment could facilitate fermentative detoxification, and supplementation with minerals was instrumental in reducing gossypol levels during mixed culture solid substrate fermentation of CSM.