A New Rapid Spectrophotometric Quantitative Determination Method for γ-Decalactone and Application in High-throughput Screening for γ-Decalactone Producing Strains

Yuping Zhao,Xiaoqing Mu,Yao Nie,Yan Xu 한국식품과학회 2014 Food Science and Biotechnology Vol.23 No.6

A new, rapid spectrophotometric quantitativedetermination method for γ-decalactone (GDL) was developedbased on the ferric hydroxamate reaction. Samples addedto a mixture of NH2OH·HCl and NaOH were heated toreact. Then HCl was added. Ferric chloride was added forcoloration, and 75% (v/v) ethanol was added. Absorbancevalues were measured after coloring for 10 min. Theconcentration range of a GDL calibration curve was 0.125-8.14 g/L. A 96-well plate high-throughput screening methodwas established to obtain desirable strains. A total of 215GDL-producing strains were identified from 4,327 samples. The highest production was 179 mg/L.

Wild Rosa roxburghii Tratt Juices Grown at Different Altitudes Regulate Blood Glucose in Type 1 Diabetic Mice via the PI3K/Akt Pathway

Yuping Zhu,Suzhen Zhai,Bei Li,Ziyi Zhao,Jiao Xie,Tingyuan Ren 한국식품영양과학회 2023 Journal of medicinal food Vol.26 No.11

To explore hypoglycemic effect of wild Rosa roxburghii tratt (RRT) juice at different altitudes on type 1diabetes mellitus (T1DM). The T1DM mouse model was induced by streptozotocin (STZ), and the experiment included anormal group (NC), model group (MC), wild RRT juice groups high (HF), medium (MF), low altitude (DF) and cultivatedcontrol group (PC). During experiment, food intake, water intake, body weight, and fasting blood glucose were measured. After 28 days of administration, glucose tolerance, glycogen level, lipid profiles, and antioxidation levels in serum and liverwere measured, and histomorphological changes of liver and kidney were observed by hematoxylin and eosin staining. The results showed that wild RRT juice reduced blood glucose level, alleviated liver and kidney tissue damage, improvedglucose and lipid metabolism disorders and attenuated oxidative damage in T1DM mice. Western blot showed that wild RRTjuice at grown at different altitudes significantly increased protein abundance of PI3K, Akt, and GLUT2 in liver of T1DMmice. In conclusion, wild RRT juice from different altitudes improved glucose and lipid metabolism disorders and oxidativedamage in T1DM mice, which may be attributed to activation of PI3K/Akt pathway. Overall effect: MF > PC > HF > DF.

Test for the covariance matrix in time-varying coefficients panel data models with fixed effects

Yuping Hu,Sanying Feng,Jing Zhao 한국통계학회 2021 Journal of the Korean Statistical Society Vol.50 No.2

This paper proposes tests for the null of sphericity and identity matrix for nonparametric time-varying coefficient panel data models with fixed effects. Firstly, based on the local linear smoothing technique, the estimators of the unknown coefficient functions and model residuals are obtained. Secondly, proper test statistics are proposed aiming at tests for sphericity or identity matrix with a large number of cross sectional units and time series observations. In addition, the limiting distributions of the proposed test statistics are derived based on random matrix theory. At last, some simulation studies are conducted to examine the finite sample performance for the proposed test statistics and a real data example is analyzed.

Experimental Investigation on Seismic Resistance of RC Shear Walls with CFRP Bars in Boundary Elements

Jun Zhao,Fuqiang Shen,Chenzhe Si,Yuping Sun,Lu Yin 한국콘크리트학회 2020 International Journal of Concrete Structures and M Vol.14 No.1

Experimental investigation on seismic performance of RC shear walls reinforced with CFRP bars in boundary elements to enhance the resilience was presented which is expected for stable resistance capacity and small residual deformation. Six RC shear walls reinforced with CFRP bars as longitudinal tensile materials in boundary elements were tested under reversed cyclic lateral loading while subjected to constant axial compression with different axial load ratios of 0.17, 0.26 and 0.33, respectively. Two forms of stirrups were used for each axial load ratio, which were rectangular and circular stirrups in boundary elements. A reference specimen, ordinary RC shear walls, was also introduced to certify the excellence of CFRP bars. The test results indicated that the walls utilizing CFRP bars had small residual deformations and residual crack widths. Lower crack propagation height and larger concrete crushing region, bearing capacity and equivalent viscous damping coefficient (EVDC) could be observed with the increase of axial load ratios. The effects of stirrup forms on experimental results had a relation to the axial load ratio. When the axial load ratio was small, the shear walls with circular stirrups had better energy dissipation than that with rectangular stirrups at a given drift level, while the cumulative energy dissipation (CED) were similar. With the increase of axial load ratio, the walls exhibited similar energy dissipation at the same drift level, however, the shear walls with rectangular stirrups had larger CED.

Magnetic properties and enhanced thermoelectric performance in Cu-doped Ca3Co2O6 single crystals

Jiyue Song,Bangchuan Zhao,Yanan Huang,Yanfeng Qin,Wenhai Song,Yuping Sun 한국물리학회 2017 Current Applied Physics Vol.17 No.5

The effect of Cu doping on the structural, magnetic, electrical and thermal transport properties of Ca3Co2- xCuxO6 single crystals has been investigated systematically. Based on the analysis of the structural parameter and x-ray photoelectron spectroscopy spectra, the valence state of Cu is considered to be þ2. All samples undergo a long-range spin density wave (SDW) transition at TN and a glass-like magnetic transition at Tf with decreasing temperature. Both TN and Tf decrease monotonously with increasing Cudoping content. A series of magnetization steps can be observed in the M(H) curve of Ca3Co2O6, and the magnetization steps are sensitive to the sample cooling magnetic field and Cu doping content x. With the increase of x, the resistivity along c-axis decreases while the thermopower increases. As a result, the figure of merit (ZT) increases considerably and the room-temperature ZT value of the sample with x ¼ 0.6 is nearly 60 times larger than that of the un-doped crystal.

Arginine Supplementation Recovered the IFN-γ-Mediated Decrease in Milk Protein and Fat Synthesis by Inhibiting the GCN2/eIF2α Pathway, Which Induces Autophagy in Primary Bovine Mammary Epithelial Cells

Xia, Xiaojing,Che, Yanyi,Gao, Yuanyuan,Zhao, Shuang,Ao, Changjin,Yang, Hongjian,Liu, Juxiong,Liu, Guowen,Han, Wenyu,Wang, Yuping,Lei, Liancheng Korean Society for Molecular and Cellular Biology 2016 Molecules and cells Vol.39 No.5

During the lactation cycle of the bovine mammary gland, autophagy is induced in bovine mammary epithelial cells (BMECs) as a cellular homeostasis and survival mechanism. Interferon gamma ($IFN-{\gamma}$) is an important antiproliferative and apoptogenic factor that has been shown to induce autophagy in multiple cell lines in vitro. However, it remains unclear whether $IFN-{\gamma}$ can induce autophagy and whether autophagy affects milk synthesis in BMECs. To understand whether $IFN-{\gamma}$ affects milk synthesis, we isolated and purified primary BMECs and investigated the effect of $IFN-{\gamma}$ on milk synthesis in primary BMECs in vitro. The results showed that $IFN-{\gamma}$ significantly inhibits milk synthesis and that autophagy was clearly induced in primary BMECs in vitro within 24 h. Interestingly, autophagy was observed following $IFN-{\gamma}$ treatment, and the inhibition of autophagy can improve milk protein and milk fat synthesis. Conversely, upregulation of autophagy decreased milk synthesis. Furthermore, mechanistic analysis confirmed that $IFN-{\gamma}$ mediated autophagy by depleting arginine and inhibiting the general control nonderepressible-2 kinase (GCN2)/eukaryotic initiation factor $2{\alpha}$ ($eIF2{\alpha}$) signaling pathway in BMECs. Then, it was found that arginine supplementation could attenuate $IFN-{\gamma}$-induced autophagy and recover milk synthesis to some extent. These findings may not only provide a novel measure for preventing the $IFN-{\gamma}$-induced decrease in milk quality but also a useful therapeutic approach for $IFN-{\gamma}$-associated breast diseases in other animals and humans.

Coloration and Decoloration of Textiles Using a TiO2 Composite Pigment

Xiao Wang,Yunzhe Xie,Cheng Huang,Yongzhu Cui,Lihua Lyu,Yuping Zhao,Ju Wei 한국섬유공학회 2018 Fibers and polymers Vol.19 No.7

A colorable pigment was prepared by dye adsorption onto titanium dioxide and subsequent silane coating. The effects of pH value, dye concentration, and adsorption times on dye adsorption were discussed. Large adsorption capacity of an anionic dye was obtained at pH value of 2 and the adsorption process was well described by the Langmuir isotherm model. Good dyeability and color fastness of pigment dyed fabric were achieved in the normal life cycle under sunlight. The decoloration of pigment was realized through photocatalytic degradation of dye molecules by titanium dioxide under ultraviolet irradiation when reusing the pigment dyed textiles after disposal. The new absorption peaks in the FTIR spectrum at 2924.95 cm-1, 1714.91 cm-1, 1461.17 cm-1, and 1289 cm-1 verified silane modification. Silane modification improved fixation of dyes onto the pigment and immobilization of pigments onto substrates. The close attachment of silane coating layer to titanium dioxide was conducive to photodegradation of dye molecules in the pigment.

Arginine Supplementation Recovered the IFN-gamma-Mediated Decrease in Milk Protein and Fat Synthesis by Inhibiting the GCN2/eIF2alpha Pathway, Which Induces Autophagy in Primary Bovine Mammary Epithelial Cells

Liancheng Lei,Xiaojing Xia,Yanyi Che,Yuanyuan Gao,Shuang Zhao,Changjin Ao,Hongjian Yang,Juxiong Liu,Guo-wen Liu,Wenyu Han,Yuping Wang 한국분자세포생물학회 2016 Molecules and cells Vol.39 No.5

During the lactation cycle of the bovine mammary gland, autophagy is induced in bovine mammary epithelial cells (BMECs) as a cellular homeostasis and survival mecha-nism. Interferon gamma (IFN-) is an important antiproliferative and apoptogenic factor that has been shown to induce autophagy in multiple cell lines in vitro. However, it remains unclear whether IFN- can induce autophagy and whether autophagy affects milk synthesis in BMECs. To understand whether IFN- affects milk synthesis, we isolated and purified primary BMECs and investigated the effect of IFN- on milk synthesis in primary BMECs in vitro. The results showed that IFN- significantly inhibits milk synthesis and that autophagy was clearly induced in primary BMECs in vitro within 24 h. Interestingly, autophagy was observed following IFN- treatment, and the inhibition of autophagy can improve milk protein and milk fat syn-thesis. Conversely, upregulation of autophagy decreased milk synthesis. Furthermore, mechanistic analysis con-firmed that IFN- mediated autophagy by depleting argi-nine and inhibiting the general control nonderepressible-2 kinase (GCN2)/eukaryotic initiation factor 2 (eIF2) signaling pathway in BMECs. Then, it was found that arginine supplementation could attenuate IFN--induced autophagy and recover milk synthesis to some extent. These findings may not only provide a novel measure for preventing the IFN--induced decrease in milk quality but also a useful therapeutic approach for IFN--associated breast diseases in other animals and humans.

Mechanistic Insight into Phenolic Compounds Toxicity and State-of-the-art Strategies for Enhancing the Tolerance of Escherichia coli to Phenolic Compounds

Lina Liu,Xiaolong Ma,Muhammad Bilal,Linlin Wei,Shijie Tang,Hong-zhen Luo,Yuping Zhao,Xuguo Duan 한국생물공학회 2022 Biotechnology and Bioprocess Engineering Vol.27 No.4

Efficient use of lignocellulosic biomass is a prerequisite for sustainable biofuel production while simultaneously contributing to environmental protection. However, phenolic compounds produced during the chemical treatment of lignocellulose inhibit the growth and metabolism of microorganisms, such as Escherichia coli, which is one of the ideal strains for producing target products by microbial fermentation. To provide new ideas for studying microbial tolerance to environmental stress and providing technical support for constructing the engineering strains with high yields of phenolic compounds, this review elucidates the inhibition mechanism of phenols to E. coli. Secondly, a comprehensive and systematic review of current approaches for improving the phenolic-tolerance of E. coli is provided, including strain domestication, random mutagenesis, regulating the expression of outer membrane proteins, changing the composition of membrane fatty acids, accelerating the efflux of phenolic compounds, engineered bacterial biofloc formation, and transcriptome analysis. Finally, this review ends with some questions that still exist today, and prospective strategies are outlined for further improving the phenols-tolerance of E. coli. This review provided a theoretical basis for research into microbial tolerance to environmental stress and the development of engineered strains with high yield of phenolic compounds.