Influence of water activity on inactivation of Escherichia coli O157:H7, Salmonella Typhimurium and Listeria monocytogenes in peanut butter by microwave heating

Song, W.J.,Kang, D.H. ACADEMIC PRESS LTD 2016 FOOD MICROBIOLOGY Vol.60 No.-

<P>This study evaluated the efficacy of a 915 MHz microwave with 3 different electric power levels to inactivate three pathogens in peanut butter with different a(w). Peanut butter inoculated with Escherichia coli O157:H7, Salmonella enterica serovar Typhimurium and Listeria monocytogenes (0.3, 0.4, and 0.5 a(w)) were treated with a 915 MHz microwave with 2, 4, and 6 kW for up to 5 min. Six kW 915 MHz microwave treatment for 5 min reduced these three pathogens by 1.97 to >5.17 log CFU/g. Four kW 915 MHz microwave processing for 5 min reduced these pathogens by 0.41-1.98 log CFU/g. Two kW microwave heating did not inactivate pathogens in peanut butter. Weibull and Log-Linear + Shoulder models were used to describe the survival curves of three pathogens because they exhibited shouldering behavior. T-d and T-5d values were calculated based on the Weibull and Log-Linear + Shoulder models. T-d values of the three pathogens were similar to D-values of Salmonella subjected to conventional heating at 90 degrees C but T-5d values were much shorter than those of conventional heating at 90 degrees C. Generally, increased a(w) resulted in shorter T-5d values of pathogens, but not shorter T-d values. The results of this study can be used to optimize microwave heating pasteurization system of peanut butter. (C) 2016 Published by Elsevier Ltd.</P>

15-Deoxy-Δ^12,14-prostaglandin J₂ induces p53 expression through Nrf2-mediated upregulation of heme oxygenase-1 in human breast cancer cells

Kim, D. H.,Song, N. Y.,Kim, E. H.,Na, H. K.,Joe, Y.,Chung, H. T.,Surh, Y. J. Informa Healthcare 2014 Free radical research Vol.48 No.9

<P>Heme oxygenase-1 (HO-1) is a stress-responsive enzyme that has antioxidant and cytoprotective functions. However, HO-1 has oncogenic functions in cancerous or transformed cells. In the present work, we investigated the effects of HO-1 on the expression of p53 induced by 15-deoxy-Δ<SUP>12,14</SUP>-prostaglandin J<SUB>2</SUB> (15d-PGJ<SUB>2</SUB>) in human breast cancer (MCF-7) cells. Treatment of MCF-7 cells with 15d-PGJ<SUB>2</SUB> led to time-dependent increases in the expression of p53 as well as HO-1. Upregulation of p53 expression by 15d-PGJ<SUB>2</SUB> was abrogated by si-RNA knock-down of HO-1. In MCF-7 cells transfected with HO-1 si-RNA, 15d-PGJ<SUB>2</SUB> failed to induce expression of p53 as well as HO-1. In addition, HO-1 inducers enhanced the p53 expression. We speculated that iron, a by-product of HO-1-catalyzed reactions, could mediate 15d-PGJ<SUB>2</SUB>-induced p53 expression. Upregulation of p53 expression by 15d-PGJ<SUB>2</SUB> was abrogated by the iron chelator desferrioxamine in MCF-7 cells. Iron released from heme by HO-1 activity is mostly in the Fe<SUP>2+</SUP> form. When MCF-7 cells were treated with the Fe<SUP>2+</SUP>-specific chelator phenanthroline, 15d-PGJ<SUB>2</SUB>-induced p53 expression was attenuated. In addition, levels of the Fe-sequestering protein H-ferritin were elevated in 15d-PGJ<SUB>2</SUB>-treated MCF-7 cells. In conclusion, upregulation of p53 and p21 via HO-1 induction and subsequent release of iron with accumulation of H-ferritin may confer resistance to oxidative damage in cancer cells frequently challenged by redox-cycling anticancer drugs.</P>

Quantifying herbicide dose-response and resistance in <i>Echinochloa</i> spp. by measuring root length in growth pouches

Zhang, C. J.,Lim, S. H.,Kim, J. W.,Song, J. S.,Yook, M. J.,Nah, G.,Valverde, B. E.,Kim, D. S. Canadian Science Publishing 2015 Canadian journal of plant science. Revue canadienn Vol.95 No.6

<P> Zhang, C. J., Lim, S. H., Kim, J. W., Song, J. S., Yook, M. J., Nah, G., Valverde, N. E. and Kim, D. S. 2015. Quantifying herbicide dose-response and resistance in Echinochloa spp. by measuring root length in growth pouches. Can. J. Plant Sci. 95: 1181-1192. The aim of the presented study was to develop a bioassay for rapid diagnosis of herbicide dose-response and resistance in Echinochloa. Pre-germinated seeds of Echinochloa spp. were incubated in growth pouches (18 cm×16.5 cm) containing herbicide solutions in a range of concentrations. Shoot and root lengths were measured after 6 d of incubation. Dose-responses estimated by measuring root lengths in the growth pouches were well-described by the log-logistic dose-response model and similar to those estimated by a whole-plant assay. Accurate dose-response curves were successfully generated for several herbicides with different modes of action, suggesting that the growth pouch method can be used for herbicide bioassays. The suitability of the growth pouch method for rapid diagnosis of acetyl coenzyme-A carboxylase (ACCase) and acetolactate synthase (ALS) inhibitor resistance in Echinochloa spp. was also tested. For cyhalofop-butyl, resistant and susceptible biotypes were discriminated at 180-300 mg a.i. L<SUP>−1</SUP> and 80-120 mg a.i. L<SUP>−1</SUP> for barnyardgrass (E. crus-galli) and late watergrass (E. oryzicola), respectively. For penoxsulam, the discriminatory dosage was 350-500 mg a.i. L<SUP>−1</SUP> for barnyardgrass and 650-1000 mg a.i. L<SUP>−1</SUP> for late watergrass. The method was further used to identify late watergrass biotypes resistant and susceptible to two other ALS inhibitors, azimsulfuron and bispyribac-sodium. Our results show that the growth pouch method can be reliably used in herbicide dose-response studies and to diagnose herbicide resistance in Echinochloa spp., with significant time and cost savings compared with conventional whole-plant assays. </P>

Combinatorial biosynthesis and antibacterial evaluation of glycosylated derivatives of 12-membered macrolide antibiotic YC-17

Shinde, P.B.,Han, A.R.,Cho, J.,Lee, S.R.,Ban, Y.H.,Yoo, Y.J.,Kim, E.J.,Kim, E.,Song, M.C.,Park, J.W.,Lee, D.G.,Yoon, Y.J. Elsevier Science Publishers 2013 Journal of biotechnology Vol.168 No.2

Expression plasmids carrying different deoxysugar biosynthetic gene cassettes and the gene encoding a substrate-flexible glycosyltransferase DesVII were constructed and introduced into Streptomyces venezuelae YJ003 mutant strain bearing a deletion of a desosamine biosynthetic (des) gene cluster. The resulting recombinants produced macrolide antibiotic YC-17 analogs possessing unnatural sugars replacing native d-desosamine. These metabolites were isolated and further purified using chromatographic techniques and their structures were determined as d-quinovosyl-10-deoxymethynolide, l-rhamnosyl-10-deoxymethynolide, l-olivosyl-10-deoxymethynolide, and d-boivinosyl-10-deoxymethynolide on the basis of 1D and 2D NMR and MS analyses and the stereochemistry of sugars was confirmed using coupling constant values and NOE correlations. Their antibacterial activities were evaluated in vitro against erythromycin-susceptible and -resistant Enterococcus faecium and Staphylococcus aureus. Substitution with l-rhamnose displayed better antibacterial activity than parent compound YC-17 containing native sugar d-desosamine. The present study on relationships between chemical structures and antibacterial activities could be useful in generation of novel advanced antibiotics utilizing combinatorial biosynthesis approach.

Inactivation of 3-strain cocktail pathogens inoculated into Bajirak jeotkal, salted, seasoned, and fermented short-necked clam (Tapes pilippinarum), by gamma and electron beam irradiation

Song, H.P.,Kim, B.,Yun, H.,Kim, D.H.,Kim, Y.J.,Jo, C. Butterworths ; Taylor Francis ; Elsevier Science 2009 FOOD CONTROL Vol.20 No.6

The objective of this study was to determine the efficacy of gamma and electron beam irradiation of the food-borne pathogens including 3-strain cocktail of Listeria monocytogenes (ATCC 19114, 19115, and 19111), Staphylococcus aureus (ATCC 6538, 25923, and 29213), and Vibrio parahaemolyticus (ATCC 17802, 33844, and 27969) in Bajirak jeotkal (8% salt), salted, seasoned and fermented short-necked clam, commercially available in the market. Irradiation (0.5, 1, 2, and 5kGy) significantly reduced the initial microbial level not only immediately after irradiation but also during storage at 10<SUP>o</SUP>C for 4 weeks (P<0.05). No viable cells were detected at 5kGy of irradiation at a detection limit of 10<SUP>1</SUP>CFU/g. Gamma irradiation was more effective than electron beam irradiation, and yielded D<SUB>10</SUB> values of 0.64, 0.63, and 0.29kGy for L. monocytogenes, S. aureus, and V. parahaemolyticus, and those of electron beam irradiation were 0.79, 0.81, and 0.36kGy, respectively. Results suggest that a low dose irradiation can improve the microbial quality and reduce the risk by the food-borne pathogens of Bajirak jeotkal, which has limited alternative sterilization methods due to the temperature characteristics of the products. Furthermore, in practical application, the irradiation source should be considered to obtain an effective dose for decontamination.

Tomographic 2-D X-ray imaging of toroidal fusion plasma using a tangential pinhole camera with gas electron multiplier detector

Song, I.,Jang, J.,Jeon, T.,Pacella, D.,Claps, G.,Murtas, F.,Lee, S.H.,Choe, W. Elsevier 2016 CURRENT APPLIED PHYSICS Vol.16 No.10

<P>A tangential X-ray pinhole camera based on a gas electron multiplier (GEM) detector was installed on KSTAR to study high temperature plasmas emitting X-ray photons in the energy band of 4-15 keV. The camera system consists of a triple-GEM gas chamber with a readout printed circuit board and a pinhole to image the plasma in two dimensions (2-D). The advantages of this tangential camera system include its compactness, high efficiency, energy discrimination in bands, and selectivity of the photon energy range etc. This camera system allows a selection of the viewing area through a remote control of the entire setup. The Philips-Tikhonov algorithm for tangential reconstruction was used to visualize the poloidal cross-sectional images. Phantom tests were performed with synthetic D-shaped plasma images and a comparison with the magnetic equilibrium flux surfaces from the real-time EFIT code obtaining a good agreement between each other. The 2-D X-ray images of the KSTAR plasma were successfully acquired during sawtooth crash, electron cyclotron heating, vertical displacement event, and emissivity from the injected trace Ar impurity. (C) 2016 Elsevier B.V. All rights reserved.</P>

Enhanced adipogenic differentiation and reduced collagen synthesis induced by human periodontal ligament stem cells might underlie the negative effect of recombinant human bone morphogenetic protein‐2 on periodontal regeneration

Song, D‐,S.,Park, J‐,C.,Jung, I‐,H.,Choi, S‐,H.,Cho, K‐,S.,Kim, C‐,K.,Kim, C‐,S. Blackwell Publishing Ltd 2011 Journal of periodontal research Vol.46 No.2

<P> <I>Song D‐S, Park J‐C, Jung I‐H, Choi S‐H, Cho K‐S, Kim C‐K, Kim C‐S. Enhanced adipogenic differentiation and reduced collagen synthesis induced by human periodontal ligament stem cells might underlie the negative effect of recombinant human bone morphogenetic protein‐2 on periodontal regeneration. J Periodont Res 2011; 46: 193–203. © 2010 John Wiley & Sons A/S</I> </P><P><B>Background and Objective: </B> Recombinant human bone morphogenetic protein‐2 (rhBMP‐2) is a potent inducer for the regeneration of mineralized tissue, but has a limited effect on the regeneration of cementum and periodontal ligament (PDL). The aim of the present study was to determine the effects of rhBMP‐2 on the <I>in vitro</I> and <I>in vivo</I> biologic activity of well‐characterized human PDL stem cells (hPDLSCs) and to elucidate the underlying mechanism of minimal periodontal regeneration by rhBMP‐2.</P><P><B>Material and Methods: </B> hPDLSCs were isolated and cultured, and then transplanted into an ectopic subcutaneous mouse model using a carrier treated either with or without rhBMP‐2. Comprehensive histologic, histometric and immunohistochemical analyses were performed after an 8‐wk healing period. The effects of rhBMP‐2 on the adipogenic and osteogenic/cementogenic differentiation of hPDLSCs were also evaluated. The effect of rhBMP‐2 on both soluble and insoluble collagen synthesis was analyzed, and the expression of mRNA and protein for collagen types I, II, III and V was assessed.</P><P><B>Results: </B> In the present study, rhBMP‐2 promoted both adipogenic and osteogenic/cementogenic differentiation of hPDLSCs <I>in vitro</I>, and the <I>in vivo</I> potential of hPDLSCs to form mineralized cementum and organized PDL tissue was down‐regulated following treatment with rhBMP‐2. Collagen synthesis, which plays a crucial role in the regeneration of cementum and the periodontal attachment, was significantly reduced, with associated modification of the relevant mRNA and protein expression profiles.</P><P><B>Conclusion: </B> In summary, the findings of the present study suggest that enhanced adipogenic differentiation and inhibition of collagen synthesis by hPDLSCs appear to be partly responsible for the minimal effect of rhBMP‐2 on cementum and PDL tissue regeneration by hPDLSCs.</P>

Microsatellite 를 이용한 돼지 Yorkshire 품종의 일당중체량 연관 DNA Marker 개발

송영민,김철욱,조광근,박외선,권은정,이정규,백동훈,최진성,노정만,홍연희 한국동물자원과학회 2000 한국축산학회지 Vol.42 No.4

This study was conducted to develop DNA markers related with average daily gain (ADG) using 27 pigs. Animals were divided into two groups: low ADG group had 11 pigs with 1.5 SD and high ADG group was consisted of 16 pigs with +1.5 SD. Initially, we choose and tested 78 microsatellites which could contain potential DNA markers for ADG. Part of the microsatellites were amplified by the polymerase chain reaction (PCR) and then electrophoresed on a agarose gel followed by the allelic, genotypic and statistical analysis. According to the alleic frequency analysis, 21 DNA polymorphisms were detected from 17 microsatellites and appeared to be associated with ADG (P$lt;0.05). From the genotypic frequency analysis, 14 DNA polymorphisms were found from II microsatellites and were associated with ADG. All pigs in the low ADG group had a 135:144 hetero type for the SWR308 marker, whereas all pigs in the high ADG group had a 144:144 homo type. This and possibly other selected markers could be useful for the selecting young pigs with an excellent growth potential.

Comparison of bactericidal efficiency of 7.5MeV X-rays, gamma-rays, and 10MeV e-beams

Song, B.S.,Lee, Y.,Moon, B.G.,Go, S.M.,Park, J.H.,Kim, J.K.,Jung, K.,Kim, D.H.,Ryu, S. Pergamon 2016 Radiation physics and chemistry Vol.125 No.-

<P>This study was performed to verify the feasibility of 7.5 MeV X-rays for food pasteurization through a comparison of the bactericidal efficiency with those of other sources for selected bacterial pathogens. No significant differences were observed between the overall bactericidal efficiency for beef-inoculated pathogens based on the uncertainty of the absorbed dose and variations in bacterial counts. This result supported that all three irradiation sources were effective for inactivation of food-borne bacteria and that 7.5 MeV X-rays may be used for food pasteurization. (C) 2016 Elsevier Ltd. All rights reserved.</P>

도시형 자기부상열차 대차 프레임의 피로강도 평가

한정우(J. W. Han),김흥섭(H. S. Kim),김재동(J. D. Kim),송시엽(S. Y. Song),최정용(J. Y. Choi) 대한기계학회 2012 대한기계학회 춘추학술대회 Vol.2012 No.11

This study evaluated fatigue strength for bogie frame of an urban maglev train including performing fatigue analysis, cumulative damage and fatigue test based on a developed fatigue load. The results of FEM analysis adopting load combinations showed that all data was under a fatigue limit of the butt welded joint made of A6005 in Goodman diagram. The cumulative fatigue damage was calculated at the highest level from a bolt connecting area of electromagnetic pole in casting block but the total sum was evaluated as D=0.808 based on 1×10?cycles, which indicates it did not exceed the failure criteria. In addition, as the results of fatigue test, there was no crack on the any position of the bogie frame with the results that correspond to the results of fatigue analyses.