Mevalonate production from 2,3-butanediol by Recombinant Pseudomonas putida KT2440

( Li Huiqing ),왕욱연,오병근 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

It has been found that 2,3-Butanediol is a high-value chemical which can be produced by fermenting waste gas carbon monoxide. However, there are challenges to separate 2,3-BDO because of the hydrophilicity of it. Therefore, conversion of 2,3-butanediol to other hydrophobic products is necessary. In this study, a recombinant cell is constructed, to assist mevalonate production by using 2,3-BDO as a feedstock. The plasmid with the gene which is essential for mevalonate generation was transformed into Pseudomonas putida KT2440. In the experiments on various carbon sources such as 2,3-BDO, glucose, and glycerol, it is confirmed that 2,3-BDO is the most suitable carbon source for mevalonate production. The amount of produced mevalonate under conditions using 2,3-BDO as a carbon source was 1.79 g/L, while those of glucose and glycerol were 0.11 g/L and 0.17 g/L, respectively, for 48 hours.

Microbial production of mevalonate by recombinant pseudomonas putida KT2440 using 2,3-BDO as a carbon source

( Li Huiqing ),왕욱연,오병근 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.0

It has been reported that the production of 2,3-butanediol(2,3-BDO) using carbon monoxide as a substrate is commercially viable. However, because of the hydrophilicity of 2,3-BDO, it is not easy to purify it. Therefore, it is necessary to convert 2,3-BDO to other hydrophobic products directly. In this research, for the production of mevalonate using 2,3-BDO as a substrate, recombinant cells were constructed. We transformed plasmid carrying the gene necessary for mevalonate production into Pseudomonas putida KT2440. In the experiments on various carbon sources such as 2,3-BDO, glucose and glycerol, it is confirmed that 2,3-BDO is the most suitable carbon source for mevalonate production. The amount of mevalonate produced under conditions using 2,3-BDO as a carbon source was 1.79 g / L, and the amounts of glucose and glycerol were 0.11 g / L and 0.17 g / L, respectively, for 48 hours.

Photovoltaic Modified β-Parameter-based MPPT Method with Fast Tracking

Li, Xingshuo,Wen, Huiqing,Jiang, Lin,Lim, Eng Gee,Du, Yang,Zhao, Chenhao The Korean Institute of Power Electronics 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

Maximum power point tracking (MPPT) is necessary for photovoltaic (PV) power system application to extract the maximum possible power under changing irradiation and temperature conditions. The β-parameter-based method has many advantages over conventional MPPT methods; such advantages include fast tracking speed in the transient stage, small oscillations in the steady state, and moderate implementation complexity. However, a problem in the implementation of the conventional beta method is the choice of an appropriate scaling factor N, which greatly affects both the steady-state and transient performance. Therefore, this paper proposes a modified β-parameter-based method, and the determination of the N is discussed in detail. The study shows that the choice of the scaling factor N is determined by the changes of the value of β during changes in irradiation or temperature. The proposed method can respond accurately and quickly during changes in irradiation or temperature. To verify the proposed method, a photovoltaic power system with MPPT function was built in Matlab/Simulink, and an experimental prototype was constructed with a solar array emulator and dSPACE. Simulation and experimental results are illustrated to show the advantages of the improved β-parameter-based method with the optimized scaling factor.

Photovoltaic Modified β-Parameter-based MPPT Method with Fast Tracking

Xingshuo Li,Huiqing Wen,Lin Jiang,Eng Gee Lim,Yang Du,Chenhao Zhao 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.1

Maximum power point tracking (MPPT) is necessary for photovoltaic (PV) power system application to extract the maximum possible power under changing irradiation and temperature conditions. The β-parameter-based method has many advantages over conventional MPPT methods; such advantages include fast tracking speed in the transient stage, small oscillations in the steady state, and moderate implementation complexity. However, a problem in the implementation of the conventional beta method is the choice of an appropriate scaling factor N, which greatly affects both the steady-state and transient performance. Therefore, this paper proposes a modified β-parameter-based method, and the determination of the N is discussed in detail. The study shows that the choice of the scaling factor N is determined by the changes of the value of β during changes in irradiation or temperature. The proposed method can respond accurately and quickly during changes in irradiation or temperature. To verify the proposed method, a photovoltaic power system with MPPT function was built in Matlab/Simulink, and an experimental prototype was constructed with a solar array emulator and dSPACE. Simulation and experimental results are illustrated to show the advantages of the improved β-parameter-based method with the optimized scaling factor.

Plasma extracellular vesicle delivery of miR-210-3p by targeting ATG7 to promote sepsis-induced acute lung injury by regulating autophagy and activating inflammation

Guang Li,Bo Wang,Xiangchao Ding,Xinghua Zhang,Jian Tang,Huiqing Lin 생화학분자생물학회 2021 Experimental and molecular medicine Vol.53 No.-

Extracellular vesicles (EVs) can be used for intercellular communication by facilitating the transfer of miRNAs from one cell to a recipient cell. MicroRNA (miR)-210-3p is released into the blood during sepsis, inducing cytokine production and promoting leukocyte migration. Thus, the current study aimed to elucidate the role of plasma EVs in delivering miR-210-3p in sepsis-inducedacute lung injury (ALI). Plasma EVs were isolated from septic patients, after which the expression of various inflammatory factors was measured using enzyme-linked immunosorbent assay. Cell viability and apoptosis were measured via cell counting kit-8 and flow cytometry. Transendothelial resistance and fluorescein isothiocyanate fluorescence were used to measure endothelial cellpermeability. Matrigel was used to examine the tubulogenesis of endothelial cells. The targeting relationship between miR-210-3p and ATG7 was assessed by dual-luciferase reporter assays. The expression of ATG7 and autophagy-related genes was determined to examine autophagic activation. A sepsis mouse model was established by cecal ligation and puncture (CLP)-induced surgery. The level of miR-210-3p was highly enriched in septic EVs. MiR-210-3p enhanced THP-1 macrophage inflammation, BEAS-2B cell apoptosis, and HLMVEC permeability while inhibiting angiogenesis and cellular activity. MiR-210-3p overexpression reduced ATG7 and LC3II/LC3I expression and increased P62 expression. Improvements in vascular density and autophagosome formation, increased ATG7 expression, and changes in the ratio of LC3II/LC3I were detected, as well as reduced P62 expression, in adenovirusanti-miR-210-3p treated mice after CLP injury. Taken together, the key findings of the current study demonstrate that plasma EVs carrying miR-210-3p target ATG7 to regulate autophagy and inflammatory activation in a sepsis-induced ALI model.

Improved Beta parameter based MPPT method in Photovoltaic system

Xingshuo Li,Huiqing Wen,Chenhao Zhao 전력전자학회 2015 ICPE(ISPE)논문집 Vol.2015 No.6

Maximum power point tracking(MPPT) is very important in relation to solar energy development. Currently, there are two problems facing the existing MPPT methods namely the tradeoff between the steady-state oscillations and dynamic behavior, and then the tradeoff between high computational load and accuracy. The Beta method can address these two problems since it shows a fast tracking speed in the transient stage, smaller oscillations in the steady-state and medium complexity of implementation. However, for optimal performance, it is essential to identify the configuration of the parameters with regard to the Beta method. Therefore, paper will examine the different performance level with the different values of the parameters, and then will provide an optimum example. In order to verify this procedure, a boost converter was proposed in MatLab/Simulink for simulation. Finally, an experimental prototype was constructed with a solar array emulator and DSPACE.

Evaluation of MPPT and APC Performance Connected with Different DC Load Types

Xingshuo Li,Huiqing Wen 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

So far, a large number of MPPT techniques have been reported, compared and evaluated. However, the performance of MPPT methods with different DC loads is not evaluated yet. Besides, the difference between DC loads for the active power control (APC) schemes is also not compared and evaluated yet. Therefore, in this paper, two different DC load types, namely resistive load and battery load, are used to make a comparison. In order to validate the difference between the different load types, simulation and experimental results when the solar irradiance changes are provided. It will be very useful to the design the MPPT and APC method in practical.

An Adaptive Constant Power Generation Control Scheme with Simple MPP Estimation for Photovoltaic Systems

Yinxiao Zhu,Huiqing Wen,Guanying Chu,Xingshuo Li 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

With consideration of instability in environmental conditions, the increasing installation of maximum power point (MPP) operational Photovoltaic systems (PVSs) injects an unstable power generation to the grid (such as, overloading). Aiming to reduce the instable generation during continuous peak power generation, an adaptive constant power generation (CPG) algorithm is proposed in this paper. With the proposed control, the system can operate at MPP tracking (MPPT) mode or CPG mode with the detection from system operators. When the operation mode is detected, the control will operate with self-judgment including regulate the initial mode during CPG with a simple MPP initial MPP estimation. With the estimation of MPP and internal step-size regulation, the response speed, an important factor in variable environments, can be improved. In order to evaluate the proposed scheme, simulation and experiment in different condition, such as changing irradiation and changing limit power level are carried out.

Connectivity map identifies luteolin as a treatment option of ischemic stroke by inhibiting MMP9 and activation of the PI3K/ Akt signaling pathway

Shijian Luo,Huiqing Li,Zhihuai Mo,Junjie Lei,Lingjuan Zhu,Yanxia Huang,Ruying Fu,Chunyi Li,Yihuan Huang,Kejia Liu,Wenli Chen,Lei Zhang 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

This study aimed to explore potential new drugs in the treatment of ischemic stroke by Connectivity Map (CMap) and to determine the role of luteolin on ischemic stroke according to its effects on matrix metalloproteinase-9 (MMP9) and PI3K/Akt signaling pathway. Based on published gene expression data, differentially expressed genes were obtained by microarray analysis. Potential compounds for ischemic stroke therapy were obtained by CMap analysis. Cytoscape and gene set enrichment analysis (GSEA) were used to discover signaling pathways connected to ischemic stroke. Cell apoptosis and viability were, respectively, evaluated by flow cytometry and an MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5- diphenyl-2-H-tetrazolium bromide) assay. Quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis were used to test the expression of MMP9 and the PI3K/Akt signaling pathway-related proteins in human brain microvascular endothelial cells (HBMECs) and tissues. Additionally, the infarct volume after middle cerebral artery occlusion (MCAO) was determined by a TTC (2,3,5-triphenyltetrazolium chloride) assay. The microarray and CMap analyses identified luteolin as a promising compound for future therapies for ischemic stroke. Cytoscape and GSEA showed that the PI3K/Akt signaling pathway was crucial in ischemic stroke. Cell experiments revealed that luteolin enhanced cell viability and downregulated apoptosis via inhibiting MMP9 and activating the PI3K/Akt signaling pathway. Experiments performed in vivo also demonstrated that luteolin reduced the infarct volume. These results suggest that luteolin has potential in the treatment of ischemic stroke through inhibiting MMP9 and activating PI3K/ Akt signaling pathway.

Fault Analysis and Fault-Tolerant Method of Dual Active Bridge Converter under Triple Phase Shift Control

Haochen Shi,Huiqing Wen,Jinglin Li 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

The open circuit fault on switches serious threat safe operation of DAB converter. In this paper, the fault phenomena of different switches during various operation condition under triple phase shift control is presented. Based on those analysis, the advanced fault diagnose which uses midpoint voltage as diagnosis criteria. It can ensure fast detect and accurate locate failure switch. After the failure switch is located, fault-tolerant is presented to maintain power transmission ability of DAB converter and ensure safe operation. Experimental result of proposed open circuit fault performance, fault diagnose method and fault-tolerant method is validated with experimental result.