Production of Tween 80-inducing Esterase by Acinetobacter sp. B1 Using Response Surface Methodology

Ma, Peiyu,Li, Yuqi,Miao, Chensi,Sun, Yunpeng,Liu, Chunhui,Li, Huijuan The Korean Society for Microbiology and Biotechnol 2019 한국미생물·생명공학회지 Vol.47 No.1

Esterase produced by Acinetobacter sp. B1 (strain B1) was optimized by means of one-variable-at-a-time and response surface methodologies. Results of the one-variable-at-a-time experiment showed that Tween 80 significantly increased esterase production of strain B1. The addition of Tween 80 to the culture medium increased the biomass and esterase activity of strain B1, stimulated content of total extracellular protein, and enhanced the oleic acid (C18:1) composition in the cell membrane of strain B1. The influence of eight culture variables on esterase production was evaluated by Plackett-Burman design. Results showed that Tween 80, pH, and $K_2HPO_4$ significantly affected the esterase production of strain B1. Tween 80, pH, and $K_2HPO_4$ were further optimized by central composite design. Under the optimized conditions (w/v, soluble starch 2.5%, tryptone 1.5%, Tween 80 0.8%, $K_2HPO_4$ 0.5%, NaCl 0.5%, pH 8.0, inoculum size 1%, and inoculum age 24 h), the maximum esterase activity of strain B1 was 152.13 U/ml, which was 10-fold higher than that of non-optimization after 36 h cultivation.

Analysis of influencing parameters and reactive substance for enrofloxacin degradation in a dielectric barrier discharge plasma/peroxydisulfate system

Shilin Song,Huijuan Wang,Yuyue Huang,Yixing Ma 대한환경공학회 2024 Environmental Engineering Research Vol.29 No.4

In this paper, the chemical and physical effects generated during the dielectric barrier discharge plasma (DBDP) process, including O₃, H₂O₂, light, e<SUP>*</SUP>, etc., were utilized to activate the peroxydisulfate (PDS) to form SO₄<SUP>−</SUP>•. Then, the original reactive oxygen species (ROS), such as •OH, formed in the discharge system was combined to degrade the enrofloxacin (ENR) in water, and the corresponding influencing parameters and reactive substance in the DBDP/PDS system were analyzed. From the investigation, it was found that the neutral (pH =6.5) solution was more conducive to the ENR decomposition than the acidic and alkaline solution conditions. The presence of Fe<SUP>2+</SUP> and Cu<SUP>2+</SUP> in the reaction solution could hasten the ENR degradation, whereas the addition of Cl<SUP>−</SUP> and the HCO₃<SUP>−</SUP> in the solution had a negative effect. Analysis of the reactive species and quenching tests were carried out to explore the generation of H₂O₂, O₃, •OH, and SO₄<SUP>−</SUP>• in the DBDP/PDS system and their effects on the ENR degradation. The UV-Vis and 3D fluorescence spectra analysis were applied to demonstrate the cooperative effects of the DBDP and the PDS. The TOC and COD removals of the ENR solutions in the DBDP and the DBDP/PDS systems were also compared. Based on the intermediates analysis of the ENR degradation, three possible pathways of ENR decomposition in the synergistic system have been inferred.

Comparison of Direct and Extraction Immunoassay Methods With Liquid Chromatography-Tandem Mass Spectrometry Measurement of Urinary Free Cortisol for the Diagnosis of Cushing’s Syndrome

Mu Danni,Fang Jiadan,Yu Songlin,Ma Yichen,Cheng Jin,Hu Yingying,Song Ailing,Zhao Fang,Zhang Qi,Qi Zhihong,Zhang Kui,Xia Liangyu,Qiu Ling,Zhu Huijuan,Cheng Xinqi 대한진단검사의학회 2024 Annals of Laboratory Medicine Vol.44 No.1

Background: Twenty-four-hour urinary free cortisol (UFC) measurement is the initial diagnostic test for Cushing’s syndrome (CS). We compared UFC determination by both direct and extraction immunoassays using Abbott Architect, Siemens Atellica Solution, and Beckman DxI800 with liquid chromatography-tandem mass spectrometry (LC-MS/MS). In addition, we evaluated the value of 24-hr UFC measured by six methods for diagnosing CS. Methods: Residual 24-hr urine samples of 94 CS and 246 non-CS patients were collected. A laboratory-developed LC-MS/MS method was used as reference. UFC was measured by direct assays (D) using Abbott, Siemens, and Beckman platforms and by extraction assays (E) using Siemens and Beckman platforms. Method was compared using Passing–Bablok regression and Bland–Altman plot analyses. Cut-off values for the six assays and corresponding sensitivities and specificities were calculated by ROC analysis. Results: Abbott-D, Beckman-E, Siemens-E, and Siemens-D showed strong correlations with LC-MS/MS (Spearman coefficient r=0.965, 0.922, 0.922, and 0.897, respectively), while Beckman-D showed weaker correlation (r=0.755). All immunoassays showed proportionally positive bias. The areas under the curve were 0.975 for Abbott-D, 0.972 for LC-MS/MS, 0.966 for Siemens-E, 0.948 for Siemens-D, 0.955 for Beckman-E, and 0.877 for Beckman-D. The cut-off values varied significantly (154.8–1,321.5 nmol/24 hrs). Assay sensitivity and specificity ranged from 76.1% to 93.2% and from 93.0% to 97.1%, respectively. Conclusions: Commercially available immunoassays for measuring UFC show different levels of analytical consistency compared to LC-MS/MS. Abbott-D, Siemens-E, and Beckman-E have high diagnostic accuracy for CS.

Peroxisome Proliferator-Activated Receptor-Gamma Pro12Ala Polymorphism Could be a Risk Factor for Gastric Cancer

Zhao, Jing,Zhi, Zheng,Song, Guangyao,Wang, Juan,Wang, Chao,Ma, Huijuan,Yu, Xian,Sui, Aixia,Zhang, Hongtao Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.6

Background: Due to the strong inhibitory effects of $PPAR{\gamma}$ gene on the growth of cancer cells, the role of Pro12Ala polymorphism in $PPAR{\gamma}$ gene has been extensively investigated in cancer recently. However, the results were inconsistent according to cancer type. The aim of this study was to comprehensively evaluate the $PPAR{\gamma}$ Pro12Ala polymorphism and gastric cancer susceptibility. Materials and Methods: Search strategies were conducted in Pubmed, Medline (Ovid), Chinese biomedical database (CBM), China national knowledge infrastructure (CNKI), VIP, and Wanfang database, covering all publications, with the last search up to November 01, 2014. The strength of association between $PPAR{\gamma}$ Pro12Ala polymorphism and gastric cancer risk was assessed by OR with 95%CI. Results: A total of 546 cases and 827 controls in 5 case-control studies were included in this meta-analysis. The results indicated that the variant G allele carriers (CG+GG) had a 2.31 times higher risk for gastric cancer when compared with the homozygote CC (odds ratio (OR)=2.31, 95% confidence interval (CI)=1.67-3.21 for CG+GG vs. CC). In the subgroup analysis by ethnicity, significantly elevated risks were both found in Asians (OR=2.56, 95% CI=1.42-4.64) and Caucasians (OR=2.20, 95% CI=1.48-3.25). Similarly, in the subgroup analysis by H. pylori status, a significantly increased risk was identified in H. pylori (+) populations (OR=3.68, 95%CI=2.07-6.52), but not in H. pylori(-) populations (OR=1.17, 95%CI=0.58-2.39). Conclusions: This pooled analysis suggested that the $PPAR{\gamma}$ Pro12Ala polymorphism could be an independent predictive risk factor for gastric cancer especially in H. pylori infected populations in Asians and Caucasians. Nevertheless, prospectively designed cohort studies are needed to further investigate gene-gene and gene-environment interactions to confirm the combined effects of $PPAR{\gamma}$ Pro12Ala polymorphisms and H. pylori infection on gastric cancer risk.

Modulation of the lattice structure of 2D carbon‑based materials for improving photo/electric properties

Fangyi Li,Yulianti Anjarsari,Jiamei Wang,Rifda Azzahiidah,Jizhou Jiang,Jing Zou,Kun Xiang,Huijuan Ma,Arramel 한국탄소학회 2023 Carbon Letters Vol.33 No.5

Reliable, inexpensive, environment-friendly, and durable properties of carbon materials with unique and outstanding photoelectric performance is highly desired for myriad of applications such as catalysis and energy storage. Since lattice modulation is a vital method of surface modification of materials, which form by an external force during the synthesis process, causing the internal compression and stretching, leading to lattice sliding event. In this review, we present a summary of different methods to tailor the lattice modulation in 2D carbon-based materials, including grain/twin boundary, lattice strain, lattice distortion, and lattice defects. This overview highlights the implication control of the diverse morphologies of nanocrystals and how to tailor the materials properties without adding any polymers. The improvement in the performance of 2D carbon materials ranges from the enhancement of charge transport and conductivity, structural stability, high-performance of light absorption capacity, and efficient selectivity promote the future prospect of 2D carbon materials broaden their applications in terms of energy conversion and storage. Finally, some perspectives are proposed on the future developments and challenges on 2D carbon materials towards energy storage applications.

Recent advances of MXenes Mo2C‑based materials for efficient photocatalytic hydrogen evolution reaction

Jiamei Wang,Qin Qin,Fangyi Li,Yulianti Anjarsari,Wei Sun,Rifda Azzahiidah,Jing Zou,Kun Xiang,Huijuan Ma,Jizhou Jiang,Arramel 한국탄소학회 2023 Carbon Letters Vol.33 No.5

The emergence of Mo2C- based catalysts in recent years has been favored as promising contender within diverse class MXenes. In terms of rapid development in the photocatalytic application, these intriguing compounds exhibit excellent photocatalytic performance because of their superior optical properties and peculiar structure characteristics. Unfortunately, a systematic review of Mo2C- based catalysts is lacking. In this review, we abstract the implication of structure—property relationship of emerging Mo2C- based MXenes materials and their applications toward the photocatalytic hydrogen evolution reaction (HER). Furthermore, synthetic pathways to prepare high-quality, low cost Mo2C- based MXenes materials and their outcomes for high HER applications are systematically described. Finally, several insights are provided into the prospects and future challenges for the development of highly reactive Mo2C- based MXenes materials, which present large range opportunities in this promising 2D materials for green and clean energy in environmental fields. This review provides a comprehensive scientific guide to the preparation, modification, and photocatalytic HER of MXenes-based materials.