Cloning and Characterization of Ginsenoside-Hydrolyzing β-Glucosidase from Lactobacillus brevis That Transforms Ginsenosides Rb1 and F2 into Ginsenoside Rd and Compound K

( Fei-liang Zhong ),( Rui Ma ),( Mingliang Jiang ),( Wei-wei Dong ),( Jun Jiang ),( Songquan Wu ),( Donghao Li ),( Lin-hu Quan ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.10

The ginsenoside-hydrolyzing β-glucosidase gene (bgy2) was cloned from Lactobacillus brevis. We expressed this gene in Escherichia coli BL21(DE3), isolated the resulting protein, and then utilized the enzyme for the biotransformation of ginsenosides. The bgy2 gene contains 2,223 bp, and encodes a protein of 741 amino acids that is a member of glycosyl hydrolase family 3. β-Glucosidase (Bgy2) cleaved the outer glucose moieties of ginsenosides at the C-20 position, and the inner glucose at the C-3 position. Under optimal conditions (pH 7.0, 30˚C), we used 0.1 mg/ml Bgy2 in 20 mM sodium phosphate buffer (PBS) for enzymatic studies. In these conditions, 1.0 mg/ml ginsenoside Rb1 and ginsenoside F2 were converted into 0.59 mg/ml ginsenoside Rd and 0.72mg/ml compound K, with molar conversion productivities of 69% and 91%, respectively. In pharmaceutical and commercial industries, this recombinant Bgy2 would be suitable for producting ginsenoside Rd and compound K.

Improvement of the Shearing Behaviour of Loess Using Recycled Straw Fiber Reinforcement

Zhong-Fei Xue,Wen-Chieh Cheng,Lin Wang,Geyang Song 대한토목학회 2021 KSCE Journal of Civil Engineering Vol.25 No.9

Reinforcing structural members and construction materials using recycled fibers has become popular in the past decades due to sustainable development concerns. The recycled fibers as soil reinforcement elements contribute to the increase in shear strength by distributing stresses exerted in the soil along the length of the recycled fibers. Loess, widely spread over the Chinese Loess Plateau, is featured with metastable structure, large porosity, and high water sensitivity. This study presents the results of applying the large-scale stress-controlled direct shear tests on the recycled straw fiber-reinforced loess. The formation mechanism of shearing behaviour enhancement of the loess by straw fiber inclusion is revealed. The associated strain-hardening behaviour can be manifested using the dilation angle or the difference in friction angle between the large-displacement friction angle and the peak friction angle. Further, the shear strength using the displacement-controlled direct shear tests presents good correspondence with that using the stress-controlled direct shear tests. The test results explore the potential of using the recycled straw fiber-reinforced loess to protect the fragile loess environment in the northwest of China.

Biotransformation of gypenoside XVII to compound K by a recombinant β-glucosidase

Zhong, Fei-Liang,Dong, Wei-Wei,Wu, Songquan,Jiang, Jun,Yang, Deok-Chun,Li, Donghao,Quan, Lin-Hu Springer-Verlag 2016 Biotechnology letters Vol.38 No.7

In vitro Removal of Deoxynivalenol and T-2 Toxin by Lactic Acid Bacteria

Zhong-Yi Zou,Zhi-Fei He,Hong-Jun Li,Peng-Fei Han,Xiao Meng,Yu Zhang,Fang Zhou,Ke-Pei Ouyang,Xi-Yue Chen,Jun Tang 한국식품과학회 2012 Food Science and Biotechnology Vol.21 No.6

Five strains of lactic acid bacteria were tested for their ability to remove deoxynivalenol (DON) and T-2toxin from MRS broth. The ability of Lactobacillus plantarum strain 102 (LP102) was the strongest among 5strains after incubation at 37oC for 72 h. The mode of removal was physical binding, rather than biotransformation. The abilities were not significantly different between when removing single toxin and when removing mixed toxins by viable cells of LP102. DON and T-2 toxin released from LP102 viable cell-toxin complexes were 28.22±1.55 and 35.42±2.02% of total bound toxins respectively after 3times of wash with posphate buffered saline, respectively,those were 4.59±0.86 and 5.59±1.47% after incubation with simulated gastric fluid (SGF) at 37oC for 4 h, and 6.86±0.81 and 9.04±1.13% after incubation with simulated intestinal fluid (SIF) at 37oC for 4 h, respectively.

A Comparative Study of Three Imaging Modalities for Size Selection of a Watchman Left Atrial Appendage Closure Device

Zhong-bao Ruan,Fei Wang,Ge-cai Chen,Li Zhu 연세대학교의과대학 2022 Yonsei medical journal Vol.63 No.4

Purpose: To compare the results of computed tomography angiography (CTA), transesophageal echocardiography (TEE), anddigital subtraction angiography (DSA) measurements and analyze their accuracy, correlation, and consistency in patients whohave successfully undergone left atrial appendage closure (LAAC). Materials and Methods: A total of 157 non-valvular atrial fibrillation (AF) patients who underwent LAAC with Watchman deviceswere included in the study. The maximum diameter and depth of LAA were recorded using CTA, TEE, and DSA. Correlations andagreements were compared. Results: The LAAC procedure was performed successfully in all patients using the Watchman device. There was no significantdifference between DSA and TEE measurements of the diameter of the LAA ostium. LAA ostium diameter obtained by CTA,however, was greater than that from DSA and TEE. Correlations were good between LAA ostium diameter measured by TEE,CTA, and DSA and Watchman device size. DSA measurements and actual device size showed the widest limits of agreement, followedby TEE; CTA measurements showed the narrowest limits of agreement. For LAA depth measurements, mean CTA measurementswere higher than those of TEE and DSA. There was no significant difference in depth measurements among the threeimaging modalities. Conclusion: CTA, TEE, and DSA measurements exhibited good correlations with Watchman device size. The ostium diameterand depth of the LAA measured by CTA were greater than those measured by TEE and DSA. The relevance and concordance ofCTA measurements were the strongest.

Effects of TESTIN Gene Expression on Proliferation and Migration of the 5-8F Nasopharyngeal Carcinoma Cell Line

Zhong, Zhun,Zhang, Fei,Yin, Shu-Cheng Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.6

Purpose: To investigate effects of the TESTIN (TES) gene on proliferation and migration of highly metastatic nasopharyngeal carcinoma cell line 5-8F and the related mechanisms. Materials and Methods: The target gene of human nasopharyngeal carcinoma cell line 5-8F was amplified by PCR and cloned into the empty plasmid pEGFP-N1 to construct a eukaryotic expression vector pEGFP-N1-TES. This was then transfected into 5-8F cells. MTT assays, flow cytometry and scratch wound tests were used to detect the proliferation and migration of transfected 5-8F cells. Results: A cell model with stable and high expression of TES gene was successfully established. MTT assays showed that the OD value of 5-8F/TES cells was markedly lower than that of 5-8F/GFP cells and 5-8F cells (p<0.05). Flow cytometry showed that the apoptosis rate of 5-8F/TES cells was prominently increased compared with 5-8F/GFP cells and 5-8F cells (p<0.05). In vitro scratch wound assays showed that, the width of the wound area of 5-8F/TES cells narrowed slightly, while the width of the wound area of 5-8F/ GFP cells and 5-8F cells narrowed sharply, suggesting that the TES overexpression could inhibit the migration ability. Conclusions: TES gene expression remarkably inhibits the proliferation of human nasopharyngeal carcinoma cell line 5-8F and reduces its migration in vitro. Thus, it may be a potential tumor suppressor gene for nasopharyngeal carcinoma.

Migration Characteristics and Potential Ecological Environment Evaluation of Metal Elements in Surface Soil

Fei Liu,Zhong Yang,Ruihua Yang,Ruifeng Wang,Jianhai Zhou 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.5

In view of the excessive heavy metals in soil will affect the quality of crops and the personal safety of local residents, in order to analyze and evaluate the migration characteristics and potential ecological risks of heavy metals in soil in the study area, the heavy metal content, pH, regional distribution, correlation, migration characteristics, enrichment state and potential risk in 0 − 1 m soil depth were tested and analyzed. The results show that the distribution of most metal elements is closely related to pH in the soil. The contents of elements As, Cr and Hg in the soil of the study area change in an “L” shape along with the buried depth, that is, the contents of As, Cr and Hg increase generally along with the buried depth of the soil, and the contents of elements Cd and Pb decrease along with the buried depth. By analyzing the enrichment degree of heavy metals and evaluating the ecological risk degree, it can be concluded that only element Hg is moderately enriched in the soil layer of 0 − 0.4 m and Cd is the main ecological risk factor, and the potential ecological risk degree of Yuyao is between slight and moderate ecological risks.

C1420T Polymorphism of Cytosolic Serine Hydroxymethyltransferase and Risk of Cancer: a Meta-analysis

Zhong, Shan-Liang,Zhang, Jun,Hu, Qing,Chen, Wei-Xian,Ma, Teng-Fei,Zhao, Jian-Hua Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.5

A series of studies have explored the role of cytosolic serine hydroxymethyltransferase (SHMT1) C1420T polymorphism in cancer risk, but their results were conflicting rather than conclusive. To derive a more precise estimation of the association between C1420T and cancer risk, the present meta-analysis of 28 available studies with 15,121 cases and 18,023 controls was conducted. The results revealed that there was no significant association between the polymorphism and cancer risk overall. In stratified analysis by cancer type (breast cancer, gastrointestinal cancer, leukemia, lymphoma, and others), the results showed that 1420T allele was associated with decreased risk in leukemia (CT vs. CC: OR= 0.825, 95% CI =0.704-0.966; and CT+TT vs. CC: OR= 0.838, 95% CI = 0.722-0.973), but the same results were not present for other cancer types. When subgroup analysis was performed by source of control (population-based [PB] and hospital-based [HB]), a borderline inverse association was observed for the HB subgroup (CT vs. CC: OR= 0.917, 95% CI = 0.857-0.982) but not for the PB subgroup. Stratifying by geographic area (America, Asia and Europe), significant inverse association was only found in Asia subgroup (CT vs. CC: OR= 0.674, 95% CI = 0.522-0.870). In summary, the findings suggest that SHMT1 C1420T polymorphism is not associated with overall cancer development, but might decrease cancer susceptibility of Asians as well as reduce leukemia risk. Large well-designed epidemiological studies will be necessary to validate the risk identified in the current meta-analysis.

Enrichment Characteristics and Health Risk Assessment of Heavy Metals in Soil-Crops System

Fei Liu,Zhong Yang,Qiuling Li,Tao Li 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.9

The effects of heavy metals in soil-crops systems, their enrichment characteristics, and health risks were investigated by analyzing the As, Cr, Cu, Pb, Cd, and Hg in 216 paired soil and crop samples from Yuyao, Zhejiang Province, China. Statistical analyses, enrichment characteristics, and health risks to adults were assessed using the health risk assessment model used by the U. S. Environmental Protection Agency. The results showed that the main sources of heavy metals were atmospheric pollution, water pollution, and pesticide spraying, that caused local pollution in bayberry soil, and that the Pb pollution source may be industrial waste and oil combustion release. They also indicated that the sources polluting bayberry soil with Cu and Hg were probably the same, the mustard-soil system had a relatively lower absorption capacity for heavy metals, and there was a significant correlation between heavy metals in the soil-rice system. The main carcinogenic risk factors associated with bayberry intake were As and Cr, but there were no non-carcinogenic and carcinogenic risks associated with rice intake. The non-carcinogenic and carcinogenic risks associated with bayberry could be reduced by planting on land not exposed to air and industrial pollution and to avoid spraying bayberry with pesticides.

Simulation analysis and evaluation of decontamination effect of different abrasive jet process parameters on radioactively contaminated metal

Zhong Lin,Deng Jian,Zuo Zhe-wen,Huang Can-yu,Chen Bo,Lei Lin,Lei Ze-yong,Lei Jie-heng,Zhao Mu,Hua Yun-fei 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.11

A new method of numerical simulating prediction and decontamination effect evaluation for abrasive jet decontamination to radioactively contaminated metal is proposed. Based on the Computational Fluid Dynamics and Discrete Element Model (CFD-DEM) coupled simulation model, the motion patterns and distribution of abrasives can be predicted, and the decontamination effect can be evaluated by image processing and recognition technology. The impact of three key parameters (impact distance, inlet pressure, abrasive mass flow rate) on the decontamination effect is revealed. Moreover, here are experiments of reliability verification to decontamination effect and numerical simulation methods that has been conducted. The results show that: 60Co and other homogeneous solid solution radioactive pollutants can be removed by abrasive jet, and the average removal rate of Co exceeds 80%. It is reliable for the proposed numerical simulation and evaluation method because of the well goodness of fit between predicted value and actual values: The predicted values and actual values of the abrasive distribution diameter are Ф57 and Ф55; the total coverage rate is 26.42% and 23.50%; the average impact velocity is 81.73 m/s and 78.00 m/s. Further analysis shows that the impact distance has a significant impact on the distribution of abrasive particles on the target surface, the coverage rate of the core area increases at first, and then decreases with the increase of the impact distance of the nozzle, which reach a maximum of 14.44% at 300 mm. It is recommended to set the impact distance around 300 mm, because at this time the core area coverage of the abrasive is the largest and the impact velocity is stable at the highest speed of 81.94 m/s. The impact of the nozzle inlet pressure on the decontamination effect mainly affects the impact kinetic energy of the abrasive and has little impact on the distribution. The greater the inlet pressure, the greater the impact kinetic energy, and the stronger the decontamination ability of the abrasive. But in return, the energy consumption is higher, too. For the decontamination of radioactively contaminated metals, it is recommended to set the inlet pressure of the nozzle at around 0.6 MPa. Because most of the Co elements can be removed under this pressure. Increasing the mass and flow of abrasives appropriately can enhance the decontamination effectiveness. The total mass of abrasives per unit decontamination area is suggested to be 50 g because the core area coverage rate of the abrasive is relatively large under this condition; and the nozzle wear extent is acceptable