Effects of Dietary Supplementation with Hainanmycin on Protein Degradation and Populations of Ammonia-producing Bacteria In vitro

Wang, Z.B.,Xin, H.S.,Wang, M.J.,Li, Z.Y.,Qu, Y.L.,Miao, S.J.,Zhang, Y.G. Asian Australasian Association of Animal Productio 2013 Animal Bioscience Vol.26 No.5

An in vitro fermentation was conducted to determine the effects of hainanmycin on protein degradation and populations of ammonia-producing bacteria. The substrates (DM basis) for in vitro fermentation consisted of alfalfa hay (31.7%), Chinese wild rye grass hay (28.3%), ground corn grain (24.5%), soybean meal (15.5%) with a forage: concentrate of 60:40. Treatments were the control (no additive) and hainanmycin supplemented at 0.1 (H0.1), 1 (H1), 10 (H10), and 100 mg/kg (H100) of the substrates. After 24 h of fermentation, the highest addition level of hainanmycin decreased total VFA concentration and increased the final pH. The high addition level of hainanmycin (H1, H10, and H100) reduced (p<0.05) branched-chain VFA concentration, the molar proportion of acetate and butyrate, and ratio of acetate to propionate; and increased the molar proportion of propionate, except that for H1 the in molar proportion of acetate and isobutyrate was not changed (p>0.05). After 24 h of fermentation, H10 and H100 increased (p<0.05) concentrations of peptide nitrogen and AA nitrogen and proteinase activity, and decreased (p<0.05) $NH_3$-N concentration and deaminase activity compared with control. Peptidase activitives were not affected by hainanmycin. Hainanmycin supplementation only inhibited the growth of Butyrivibrio fibrisolvens, which is one of the species of low deaminative activity. Hainanmycin supplementation also decreased (p<0.05) relative population sizes of hyper-ammonia-producing species, except for H0.1 on Clostridium aminophilum. It was concluded that dietary supplementation with hainanmycin could improve ruminal fermentation and modify protein degradation by changing population size of ammonia-producing bacteria in vitro; and the addition level of 10 mg/kg appeared to achieve the best results.

Hydrogen peroxide (H₂O₂) irreversibly inactivates creatine kinase from Pelodiscus sinensis by targeting the active site cysteine

Wang, W.,Lee, J.,Hao, H.,Park, Y.D.,Qian, G.Y. Elsevier 2017 INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES Vol.105 No.3

Creatine kinase (EC 2.7.3.2, CK) plays an important role in cellular energy metabolism and homeostasis by catalysing the transfer of phosphate between ATP and creatine phosphate. In this study, we investigated the effects of H<SUB>2</SUB>O<SUB>2</SUB> on PSCKM (muscle type creatine kinase from Pelodiscus sinensis) by the integrating method between enzyme kinetics and docking simulations. We found that H<SUB>2</SUB>O<SUB>2</SUB> strongly inactivated PSCKM (IC<SUB>50</SUB>=0.25mM) in a first-order kinetic process, and targeted the active site cysteine directly. A conformational study showed that H<SUB>2</SUB>O<SUB>2</SUB> did not induce the tertiary structural changes in PSCKM with no extensive exposure of hydrophobic surfaces. Sequential docking simulations between PSCKM and H<SUB>2</SUB>O<SUB>2</SUB> indicated that H<SUB>2</SUB>O<SUB>2</SUB> interacts with the ADP binding region of the active site, consistent with experimental results that demonstrated H<SUB>2</SUB>O<SUB>2</SUB>-induced inactivation. Our study demonstrates the effect of H<SUB>2</SUB>O<SUB>2</SUB> on PSCKM enzymatic function and unfolding, and provides important insight into the changes undergone by this central metabolic enzyme in ectothermic animals in response to the environment.

Fermentation for Liquid-type Yogurt with Lactobacillus casei 911LC

Ko, I.H.,Wang, M.K.,Jeon, B.J.,Kwak, H.S. Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.1

This study was carried out to find the attributes for liquid-type yogurt with Lactobacillus casei 911LC during 72 h fermentation at $37^{\circ}C$. The pH decreased up to 32 h and plauteaued thereafter, and the titratable acidity increased up to 40 h. The growth of lactic acid bacteria sharply increased with $3.5{\times}10^7$ cfu/ml up to 40 h of fermentation and slowly decreased thereafter. The free amino acids produced during fermentation reached the maximum value at 44 h and gradually decreased thereafter. Bitterness sensory scores were the highest at 44 h of fermentation. In the result of electrophoresis, the band mostly disappeared at 72 h fermentation. The present data showed that the range of optimum fermentation time for liquid-type yogurt using Lactobacillus casei 911LC was from 40 to 44 h.

In vivo imaging of tumor apoptosis using histone H1-targeting peptide

Wang, K.,Purushotham, S.,Lee, J.Y.,Na, M.H.,Park, H.,Oh, S.J.,Park, R.W.,Park, J.Y.,Lee, E.,Cho, B.C.,Song, M.N.,Baek, M.C.,Kwak, W.,Yoo, J.,Hoffman, A.S.,Oh, Y.K.,Kim, I.S.,Lee, B.H. Elsevier Science Publishers 2010 Journal of controlled release Vol.148 No.3

In vivo imaging of apoptosis could allow monitoring of tumor response to cancer treatments such as chemotherapy. Using phage display, we identified the CQRPPR peptide, named ApoPep-1(Apoptosis-targeting Peptide-1), that was able to home to apoptotic and necrotic cells in tumor tissue. ApoPep-1 also bound to apoptotic and necrotic cells in culture, while only little binding to live cells was observed. Its binding to apoptotic cells was not dependent on calcium ion and not competed by annexin V. The receptor for ApoPep-1 was identified to be histone H1 that was exposed on the surface of apoptotic cells. In necrotic cells, ApoPep-1 entered the cells and bound to histone H1 in the nucleus. The imaging signals produced during monitoring of tumor apoptosis in response to chemotherapy was enhanced by the homing of a fluorescent dye- or radioisotope-labeled ApoPep-1 to tumor treated with anti-cancer drugs, whereas its uptake of the liver and lung was minimal. These results suggest that ApoPep-1 holds great promise as a probe for in vivo imaging of apoptosis, while histone H1 is a unique molecular signature for this purpose.

Photoluminescent properties and site occupation preference in Bi³⁺, Eu³⁺ doped CaY₄(SiO₄)₃O phosphor

Wang, L.,Moon, B.K.,Choi, B.C.,Kim, J.H.,Shi, J.,Jeong, J.H. Ceramurgica ; Elsevier Science Ltd 2016 CERAMICS INTERNATIONAL Vol.42 No.11

Bi<SUP>3+</SUP>, Eu<SUP>3+</SUP> doped CaY<SUB>4</SUB>(SiO<SUB>4</SUB>)<SUB>3</SUB>O phosphors were synthesized through high temperature solid state reaction. Their photoluminescent properties were investigated and site occupation preference of Bi<SUP>3+</SUP> in cationic sites was analyzed. The structure of CaY<SUB>4</SUB>(SiO<SUB>4</SUB>)<SUB>3</SUB>O is characterized by three non-equivalent cationic sites with different coordination and cation-oxygen distances. By means of dielectric theory of the chemical bond for complex crystals, several kinds of chemical bond parameters like fractional covalence of CaY<SUB>4</SUB>(SiO<SUB>4</SUB>)<SUB>3</SUB>O were calculated and integrated to yield environmental factor h<SUB>e</SUB>. According to quantitative equations between the transition energy of Bi<SUP>3+</SUP> and environmental factor h<SUB>e</SUB>, the excitation bands at 308 and 226nm were assigned to <SUP>1</SUP>S<SUB>0</SUB>→<SUP>3</SUP>P<SUB>1</SUB> transition of Bi<SUP>3+</SUP> in Y(6h) and Y(4f) site, respectively. Another excitation band centered at 210nm should be the overlap of Bi<SUP>3+</SUP>A-band in Ca site and C-band in Y(6h) site. Optical band gap of pure CYSO was calculated using Kubelka-Munk method from diffuse reflectance spectra. Red emission can be realized in CaY<SUB>4</SUB>(SiO<SUB>4</SUB>)<SUB>3</SUB>O:Bi<SUP>3+</SUP>, Eu<SUP>3+</SUP> under UV light excitation because of efficient energy transfer from Bi<SUP>3+</SUP> to Eu<SUP>3+</SUP> and decay behaviors of Bi<SUP>3+</SUP> and Eu<SUP>3+</SUP> emission were investigated. Without optimization, the internal quantum efficiency of CYSO:2%Bi<SUP>3+</SUP>, 7%Eu<SUP>3+</SUP> at 310 and 393nm excitations were 31.563%, 74.252%, respectively.

A Markov jump model approach to reliable event-triggered retarded dynamic output feedback H_~ control for networked systems

Wang, J.,Chen, M.,Shen, H.,Park, J.H.,Wu, Z.G. Elsevier Science B. V., Amsterdam 2017 NONLINEAR ANALYSIS HYBRID SYSTEMS Vol.26 No.-

In this paper, the problem of reliable event-triggered H<SUB>~</SUB> control is addressed for networked control systems by using retarded dynamic output feedback. The randomness of actuators failures is modeled by a stochastic variable in a Markov jump model framework. To guarantee the considered closed-loop system is stochastically stable with a prescribed H<SUB>~</SUB> performance level, a Markov jump event-triggered retarded dynamic output feedback H<SUB>~</SUB> controller is designed in this paper, which is the main purpose of our study. By using the stochastic analysis techniques and novel integral inequalities, some sufficient conditions for the solvability of the addressed problem are derived. Finally, an example using a satellite control system model is provided to explain the validity of the proposed method.

Investigation of the surface chemical and electronic states of pyridine-capped CdSe nanocrystal films after plasma treatments using H₂, O₂, and Ar gases

Wang, S.-J.,Kim, H.,Park, H.-H.,Lee, Y.-S.,Jeon, H.,Chang, H.J. American Vacuum Society 2010 Journal of vacuum science & technology. an officia Vol.28 No.4

Effect of Monensin and Fish Oil Supplementation on Biohydrogenation and CLA Production by Rumen Bacteria In vitro When Incubated with Safflower Oil

Wang, J.H.,Choi, S.H.,Yan, C.G.,Song, M.K. Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.2

An in vitro study was conducted to examine the effect of monensin or fish oil addition on bio-hydrogenation of $C_{18^-} unsaturated fatty acids and CLA production by mixed ruminal bacteria when incubated with safflower oil. Commercially manufactured concentrate (1%, w/v) with safflower oil (0.2%, w/v) were added to mixed solution (600 ml) of strained rumen fluid and McDougalls artificial saliva (control). Monensin $Rumensin^{(R)}$, 10 ppm, w/v, MO), mixed fish oil (0.02%, w/v, absorbed to 0.2 g alfalfa hay, FO) or similar amounts of monensin and fish oil (MO+FO) to MO and FO was also added into the control solution. All the culture solutions prepared were incubated in the culture jar anaerobically at $39^{\circ}C$ up to 12 h. Higher pH (p<0.047) and ammonia concentration (p<0.042) were observed from the culture solution containing MO at 12 h incubation than those from the culture solutions of control or FO. The MO supplementation increased (p<0.0001-0.007) propionate proportion of culture solution but reduced butyrate proportion at 6 h (p<0.018) and 12 h (p<0.001) of incubations. Supplementation of MO or MO+FO increased (p<0.001) the proportions of $C_{18:2}$. The MO alone reduced (p<0.022-0.025) the proportion of c9,t11-CLA compared to FO in all incubation times. The FO supplementation increased the proportion of c9,t11-CLA. An additive effect of MO to FO in the production of c9,t11-CLA was observed at 6 h incubation. In vitro supplementation of monensin reduced hydrogenation of $C_{18^-}$UFAs while fish oil supplementation increased the production of CLA.

H∞최적 제어기법을 이용한 전력계통의 안정화에 관한 연구

정형환,이정필,허동렬,왕용필 東亞大學校 海洋資源硏究所 1998 硏究論文集 Vol.11 No.1

In this paper, we are considered various possible disturbance conditions in order to design controller, H ∞ optimal controller is successfully designed to control in such as situations. To do this, we are determined weighting function and design parameter γ to method of trial and error by Glover-Doyle algorithm. To compare with H∞-PSS and conventional-PSS which is applied in nominal system and load variations, the dynamic characteristics of H∞-PSS controller was verified which has a good response.

Bactericidal effect through non-uptake pathway with photofunctional silicon polymer that generates reactive oxygen species

Wang, K.K.,Jung, S.J.,Hwang, J.W.,Kim, B.J.,Kim, D.H.,Bae, I.K.,Jeong, S.H.,Kim, Y.R. Elsevier Sequoia 2016 Journal of photochemistry and photobiology Chemist Vol.315 No.-

<P>We report bactericidal effect of photosensitizer (H2TPP: 5,10,15,20-tetraphenyl-21H,23H-porphyrin) through non-uptake pathway and efficacy of the photofunctional silicon polymer to the decomposition of the formed biofilm and the suppression of the biofilm formation. The photoftmctional silicon polymer (PSP), which is the silicon polymer embedded with a photosensitizer, is fabricated by a simple solvent swell-encapsulation-shrink method. Reactive oxygen generation from PSP was confirmed by using the decomposition reaction of 1,3-diphnyl-isobenzofuran (DPBF). Also, singlet oxygen generation which is one of the reactive oxygen species (ROS) from PSP is directly confirmed with time and wavelength resolved singlet oxygen phosphorescence spectroscopy. For the influence study of ROS under the non-uptake condition of photosensitizer (PS to bacteria), photodynamic inactivation (PDI) effect of PSP is evaluated for Gram-positive, Gram-negative bacteria, and fungi. Those microorganisms were inactivated by PSP within 1 h under the given power of laser light (63.7 mW/cm(2)). Among the bacteria, especially, Staphylococcus aureus as the Gram-positive bacteria were completely disinfected under the given experimental condition. Furthermore, PSP successfully demonstrates the decomposition of the formed biofilm and the suppression of the biofilm formation with green light emitting diode (GLED, 3.5 mW/cm(2),lambda(max) = 517 nm, FWHM = 37 nm), which shows the practical application possibility of bactericidal material. (C) 2015 Elsevier B.V. All rights reserved.</P>