Enhancement of transglutaminase production in Streptomyces mobaraensis DSM 40587 by non-nutritional stress conditions: Effects of heat shock, alcohols, and salt treatments

Lili Zhang,Lanwei Zhang,Huaxi Yi,Ming Du,Yingchun Zhang,Xue Han,Zhen Feng,Jingyan Li,Yuehua Jiao,Yanhe Zhang,Chunfeng Guo 한국화학공학회 2012 Korean Journal of Chemical Engineering Vol.29 No.7

Stress-mediated bioprocess is a strategy designed to enhance biological target productivity. In this study,an attempt was made to enhance transglutaminase (TGase) production by Streptomyces mobaraensis by using different stress conditions including heat shock, alcohols and salt stress. Results showed that the effects of stress on TGase production depended on the type applied. For heat shock, TGase production (1.32 U/ml) was recorded maximum in the culture treated at 48 h post inoculation in water bath at 60 oC for 1 min. For alcohols treatment, the maximum activity of TGase (1.77 and 1.75 U/ml) was obtained when 3% methanol was added into the medium at 0 or 24 h of fermentation. However, a 3.5-fold increased production of TGase (3.8 U/ml) was observed in the medium supplemented with 0.2mol/l MgCl2 compared with the basic medium at the beginning of fermentation. In conclusion, TGase production from S. mobaraensis was improved by heat shock, methanol and salt stress treatments, MgCl2 stress was the most effective.

Influence of Polycaprolactone/Collagen Ratio and Microstructure of FibrousMembranes on Mechanical Properties and Anti-Platelet Properties

Jia-Shuai Zhang,Hui-Lin Mo,Shun-Yang Shen,Du-Han Zhang,Wei Zhang,Yu Ren,Mei-Xian Li 한국고분자학회 2024 폴리머 Vol.48 No.1

In this paper, polycaprolactone (PCL)/collagen (COL) nanofibrous membranes were prepared by electrospinning to study their mechanical properties as well as biocompatibility. The surface morphology was characterized by scanning electron microscopy (SEM) to access the effect of microstructure on the mechanical properties, cytocompatibility, and enzymatic degradation behaviors. In addition, the effect of hydrophilicity of membranes on the antithrombotic properties was also investigated. The results show that tensile strength of PCL/COL10 is higher than that of other samples due to smaller fiber diameters and tight spatial interlacing of PCL/COL10 membranes. In addition, the hydrophobic surface of PCL becomes hydrophilic after the addition of collagen, which affect platelet adhesion and cytocompatibility of nanofibrous membrane samples. The addition of collagen could promote the cell proliferation as well as the enzymatic degradation rate. Overall, PCL/COL10 has good morphology, the best mechanical properties, appropriate degradation rate, and the best antithrombotic effect as well as biocompatibility.

Eddy Loss Analysis and Parameter Optimization of the WPT System in Seawater

Zhang, Ke-Han,Zhu, Zheng-Biao,Du, Luo-Na,Song, Bao-Wei The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.3

Magnetic resonance wireless power transfer (WPT) in the marine environment can be utilized in many applications. However, energy loss in seawater through eddy loss (EL) is another consideration other than WPT in air. Therefore, the effect of system parameters on electric field intensity (EFI) needs to be measured and ELs calculated to optimize such a system. In this paper, the usually complicated analytical expression of EFI is simplified to the product of frequency, current, coil turns, and a coefficient to analyze the eddy current loss (ECL). Moreover, as the calculation of ECL through volume integral is time-consuming, the equivalent eddy loss impedance (EELI) is proposed to help designers determine the optimum parameters quickly. Then, a power distribution model in seawater is conceived based on the introduction of EELI. An optimization flow chart is also proposed according to this power distribution model, from which a prototype system is developed which can deliver 100 W at 90% efficiency with a gap of 30 mm and a frequency of 107.1 kHz.

Eddy Loss Analysis and Parameter Optimization of the WPT System in Seawater

Ke-Han Zhang,Zheng-Biao Zhu,Luo-Na Du,Bao-Wei Song 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.3

Magnetic resonance wireless power transfer (WPT) in the marine environment can be utilized in many applications. However, energy loss in seawater through eddy loss (EL) is another consideration other than WPT in air. Therefore, the effect of system parameters on electric field intensity (EFI) needs to be measured and ELs calculated to optimize such a system. In this paper, the usually complicated analytical expression of EFI is simplified to the product of frequency, current, coil turns, and a coefficient to analyze the eddy current loss (ECL). Moreover, as the calculation of ECL through volume integral is time-consuming, the equivalent eddy loss impedance (EELI) is proposed to help designers determine the optimum parameters quickly. Then, a power distribution model in seawater is conceived based on the introduction of EELI. An optimization flow chart is also proposed according to this power distribution model, from which a prototype system is developed which can deliver 100 W at 90% efficiency with a gap of 30 mm and a frequency of 107.1 kHz.

Ectopic expression of grape hyacinth R3 MYB repressor MaMYBx affects anthocyanin and proanthocyanidin biosynthesis and epidermal cell differentiation in Arabidopsis

Wang Jiangyu,Zhang Boxiao,Tian Shuting,Zhang Han,Gong Jiaxin,Chen Kaili,Du Lingjuan 한국원예학회 2022 Horticulture, Environment, and Biotechnology Vol.63 No.3

Single-repeat R3 MYB transcription factors regulate multiple developmental and metabolic pathways in plants. The anthocyanin-related R3 MYB repressor MaMYBx was previously identified in grape hyacinth (Muscari spp.), and its ectopic expression reduced the accumulation of anthocyanin in tobacco petals. However, whether the function of MaMYBx is conserved across plant species remains unclear. Here, we report that ectopic expression of MaMYBx regulates anthocyanin and proanthocyanidin (PA) biosynthesis and epidermal cell differentiation in Arabidopsis. MaMYBx overexpression in Arabidopsis decreased the accumulation of anthocyanin and PA by downregulating the late structural genes (AtDFR, AtANS, AtANR, and AtGST), some key regulatory factors of MBW complexes (AtPAP1, AtTT8, and AtGL3) and an R3 MYB gene (AtCPC) involved in flavonoid biosynthesis. In addition, MaMYBx also modulated trichome formation and root hair differentiation by downregulating MBW component genes (AtGL1, AtWER, and AtGL3) and their target gene AtGL2 and by upregulating several R3 MYB genes (AtTRY and AtTCL1). We further found that MaMYBx transgenic plants accumulated less anthocyanin than did wild-type plants under salt, osmotic pressure, cold, and nitrogen stresses. Moreover, the effect was even greater, and significantly less anthocyanin accumulated. In conclusion, these results implied functional conservation of MaMYBx in anthocyanin and PA biosynthesis pathways of Arabidopsis. Therefore, MaMYBx likely represents a new potential gene for the molecular breeding of horticulture and ornamental plants via the regulation of anthocyanin and PA.

일반논문 : 영화를 활용한 한국어 듣기 말하기 통합 교육 방안 -중국 현지 대학생을 대상으로-

두도장 ( Tao Zhang Du ),리한교 ( Han Jiao Li ) 연세대학교 언어정보연구원(구 연세대학교 언어정보개발원) 2010 언어사실과 관점 Vol.26 No.-

Recently the number of Korean learners has been increasing and thus, as a foreign language, Korean communication has become emphasized. Currently there are courses that teach listening and speaking. However, there are barely any courses that teach speaking and learning with an emphasis on communication. In this research, teaching using movies as a learning material is proposed for the third and fourth year students majoring in Korean at a Chinese University, who out of the four skills are weakest in listening and speaking. Because movies are visual and present a realistic situation in which the learner can indirectly experience everyday life conversations and culture, movie can easily gain the interest of the learner, so it is appropriate in raising the listening and speaking levels of the learner. First, in current Korean language education, the crucially viewed points and the necessity and goal of movies is explored. Korean language education in China, in particular the listening and speaking education is explored. Then the problems are revealed the preference of movies by university students is explored through a survey given to current 100 third and fourth year Chinese University students. Through the analysis of the survey the students reaction to movies is explored. Starting with the special features of movies, methods on how to use movies discussed. Then the connection of movies and Korean language education and what kind of effect it has is explored. Movies, as a learning material, how to effectively use them and what kind of basic features a useful movie must have is also explored. Using these basic features, a list of movies from 2001 to 2010, that have educational value, is made. Putting these features into consideration, 국가대표 is chosen as an sample movie and using this movie as learning material a Korean language teaching guide focusing on listening and speaking is presented. Finally, activities combining listening and speaking is explored.

TEMPLATE STRATEGY FOR THE SYNTHESIS OF Cu2O-Pt HIERARCHICAL HETEROSTRUCTURES FOR THE DEGRADATION OF METHYLENE BLUE

SHIYONG BAO,HAN ZHU,PAN WANG,MEILING ZOU,MINGLIANG DU,MING ZHANG 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2013 NANO Vol.8 No.6

A facile and green route was introduced to synthesize Pt nanoparticles (PtNPs) immobilized on Cu2O octahedrons to form Cu2O–Pt hierarchical heterostructure. Transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) were employed to study their morphology, chemical and crystallographic properties of the Cu2O–Pt hierarchical heterostructure. These novel Cu2O–Pt hierarchical heterostructures show fascinating degradations of methylene blue (MB), due to the suppressed electron/hole recombination phenomena and the efficient ability to capture the light.

SYNTHESIS AND CHARACTERIZATION OF AU NANOPARTICLES/REDUCED GRAPHENE OXIDE NANOCOMPOSITE: A FACILE AND ECO-FRIENDLY APPROACH

MEILING ZOU,HAN ZHU,PAN WANG,MINGLIANG DU,MING ZHANG,SHIYONG BAO 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.3

In this paper, epigallocatechin gallate (EGCG) was used as a green reductant both for thefabrication of soluble reduced graphene oxide (rGO) and the synthesis of Au nanoparticles/rGOnanocomposite. Fourier transform infrared (FTIR) spectra con¯rmed the e±cient removal of theoxygen-containing groups in graphene oxide (GO) through the reduction act of EGCG. Aunanoparticles (AuNPs) were anchored onto the rGO sheets by heating the mixed solution of rGOand chloroauric acid at 65?C using EGCG as reductant. Transmission electron microscopy(TEM), atomic force microscope (AFM) and X-ray photoelectron spectroscopy (XPS) wereemployed to characterize the resulting nanocomposite. Due to the chelating e®ect of polyhydroxyEGCG, AuNPs with diameters of ? 20 – 50 nm were stably decorated onto both sides of the rGOsheets. Because this reduction method avoids the use of toxic reagents, AuNPs/rGO nano-composite would be eco-friendly, and it might be useful not only for electronic devices but also forbiocompatible materials in the future applications.

Study on Phase-Segregated Active Power Filter using PLECS

Ying-Hao Zhang,Hyoung-Lok Oh,Han-Jun Lim,Wen-Hao Zhang,Du-Sik Kim 전력전자학회 2013 전력전자학술대회 논문집 Vol.2013 No.7

Prognostic Value of Serum Epstein–Barr Virus Antibodies and Their Correlation with TNM Classification in Patients with Locoregionally Advanced Nasopharyngeal Carcinoma

Wan-Ru Zhang,Yu-Yun Du,Chun-Yan Guo,Han-Xing Zhou,Jie-Yi Lin,Xiao-Han Meng,Hao-Yuan Mo,Dong-Hua Luo 대한암학회 2021 Cancer Research and Treatment Vol.53 No.4

Purpose This study assessed the correlation between Epstein-Barr virus (EBV) biomarkers and the eighth American Joint Committee on Cancer staging system and the prognostic values of IgG antibodies against replication and transcription activator (Rta-IgG), IgA antibodies against Epstein-Barr nuclear antigen 1, and BamH1 Z transactivator (Zta-IgA) in locoregionally advanced nasopharyngeal carcinoma (NPC) patients. Materials and Methods Serum EBV antibody levels were measured by enzyme-linked immunosorbent assay in 435 newly diagnosed stage III-IVA NPC patients administered intensity-modulated radiation therapy±chemotherapy. The primary endpoint was progression-free survival (PFS). Results Rta-IgG and Zta-IgA levels were positively correlated with the N category and clinical stage. Patients with high Rta-IgG levels (> 29.07 U/mL) showed a significantly inferior prognosis as indicated by PFS (77% vs. 89.8%, p=0.004), distant metastasis–free survival (DMFS) (88.3% vs. 95.8%, p=0.021), and local recurrence-free survival (LRFS) (91.2% vs. 98.3%, p=0.009). High Rta-IgG levels were also significantly associated with inferior PFS and LRFS in multivariable analyses. In the low-level EBV DNA group (≤ 1,500 copies/mL), patients with high Rta-IgG levels had significantly inferior PFS and DMFS (both p < 0.05). However, in the high-level EBV DNA group, Rta-IgG levels were not significantly associated with PFS, DMFS, and LRFS. In the advanced T category (T3-4) subgroup, high Rta-IgG levels were also significantly associated with inferior PFS, DMFS, and LRFS (both p < 0.05). Conclusion Rta-IgG and Zta-IgA levels were strongly correlated with the TNM classification. Rta-IgG level was a negative prognostic factor in locoregionally advanced NPC patients, especially those with advanced T category or low EBV DNA level.