Characterization and quantification of electron donating capacity and its structure dependence in biochar derived from three waste biomasses

Zhang, Yue,Xu, Xiaoyun,Cao, Lingzhi,Ok, Yong Sik,Cao, Xinde Elsevier 2018 CHEMOSPHERE - Vol.211 No.-

<P><B>Abstract</B></P> <P>Biochar has shown a unique electrochemical property being involved in various redox reactions in soil and water. In this study, the electron donating capacities (EDCs) of biochar pyrolyzed at 200–800 °C from pine wood, barley grass and wheat straw were investigated by using the mediated electrochemical oxidation method. The EDC values for all biochar were in the range of 0.18–1.83 mmol e<SUP>−</SUP> (g biochar)<SUP>−1</SUP>, showing the increase as the temperature increased from 200 °C to 400 °C, the decrease from 400 °C to 650 °C, and then increase from 650 °C until to 800 °C. At low and intermediate temperatures of 200–650 °C, the EDCs were mainly attributed to the phenolic hydroxyl groups, while the conjugated π-electron system associated with aromatic structure dominated the EDCs of biochar at the high temperatures of over 650 °C. The barley grass- and wheat straw-derived biochar had higher EDCs than the pine wood-derived biochar, resulting from the higher phenolic hydroxyl groups in the former samples than the latter one. In conclusion, the reductive property of biochar was mainly attributed to both phenolic hydroxy group and conjugated π-electron system associated with aromatic structure, depending on the pyrolytic temperature and feedstock source. The results will help us to obtain a complete view on the role of biochar in biogeochemical redox reactions and consider developing biochar with controlled redox properties for specific environmental applications such as electron shuttle and catalyst material.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Quantification of the relationship between EDCs and phenolic groups and conjugate π-electron system were reported. </LI> <LI> At low and intermediate temperatures, the EDCs were mainly attributed to the phenolic groups. </LI> <LI> At high temperatures, the conjugated π-electron system associated with aromatic structure dominated the EDCs of biochar. </LI> <LI> Developing biochar with controlled redox properties was proposed for specific environmental applications. </LI> </UL> </P>

Determining Water Depths for Monitoring Coastal Water Quality Using Multiple Functional Traits of Periphytic Protozoa in Marine Ecosystems

Congcong Guo,Xiaoyun Bai,Mamun Abdullah Al,Mohammad Nurul Azim Sikder,Henglong Xu 한국해양과학기술원 2019 Ocean science journal Vol.54 No.1

Biological trait analysis (BTA) of protozoan communities has been used a useful bioindicator of environmental quality status in marine ecosystems. To determine the optimal water depths for bioassessment using multiple functional traits of periphytic protozoa, community functioning was studied at different water depths in the Yellow Sea, northern China. The community-weighted means (CWM) of bacterivores with small sizes showed an increasing trend from surface layers to the deeper ones, while those of algivores with medium and large sizes revealed an opposite trend, i.e., a decreasing trend from surface layers to deeper ones. However, with those of predators were distributed at depths of 2 to 3.5 m. There was a significant difference in the functional patterns, except for those at depths of 2 to 3.5 m (P > 0.05). All diversity indices except FDiv generally peaked and leveled off at either 2 or 3.5 m although they decreased with depth. The results suggest that sampling at depths of 2 and 3.5 m may be an optimal strategy for assessing water quality using the functional pattern of protozoa in coastal ecosystems.

Safety and antifatigue effect of Korean Red Ginseng: a randomized, double-blind, and placebo-controlled clinical trial

Li Zhang,Xiaoyun Chen,Yanqi Cheng,Qilong Chen,Hongsheng Tan,Dongwook Son,Dongpill Chang,Zhaoxiang Bian,Hong Fang,Hongxi Xu 고려인삼학회 2019 Journal of Ginseng Research Vol.43 No.4

Background: Korean Red Ginseng (KRG) is widely used for strengthening the immune system andfighting fatigue, especially in people with deficiency syndrome. However, there is concern that the longtermapplication or a high dose of KRG can cause “fireness” (上火in Chinese) because of its “dryness” (燥性in Chinese). The aim of this study was to assess the safety and efficacy of a 4-week treatment with KRGin participants with deficiency syndrome. Methods: This was a 4-week, randomized, double-blind, placebo-controlled clinical trial. A total of 180Chinese participants were randomly allocated to three groups: placebo control group, participants weregiven a placebo, 3.6 g/d; KRG 1.8 g and 3.6 g groups. The primary outcomes were the changes in firenessand safety evaluation (adverse events, laboratory tests, and electrocardiogram). The secondary outcomeswere the efficacy of KRG on fatigue, which include the following: traditional Chinese medicine (TCM)symptom scale and fatigue self-assessment scale. Results: Of the 180 patients, 174 completed the full study. After 4 weeks of KRG treatment, the Fire-heatsymptoms score including Excess fire-heat score and Deficient fire-heat score showed no significantchange as compared with placebo treatment, and no clinically significant changes in any safetyparameter were observed. Based on the TCM syndrome score and fatigue self-assessment score, TCMsymptoms and fatigue were greatly improved after treatment with KRG, which showed a dose- and timedependenteffect. The total effective rate was also significantly increased in the KRG groups. Conclusion: Our study revealed that KRG has a potent antifatigue effect without significant adverse effectsin people with deficiency syndrome. Although a larger sample size and longer treatment may berequired for a more definite conclusion, this clinical trial is the first to disprove the common conceptionof “fireness” related to KRG.

Mesocarbon microbead densified matrix graphite A3-3 for fuel elements in molten salt reactors

Wang, Haoran,Xu, Liujun,Zhong, Yajuan,Li, Xiaoyun,Tang, Hui,Zhang, Feng,Yang, Xu,Lin, Jun,Zhu, Zhiyong,You, Yan,Lu, Junqiang,Zhu, Libing Korean Nuclear Society 2021 Nuclear Engineering and Technology Vol.53 No.5

This study aims to provide microstructural characterization for the matrix graphite which molten salt reactors (MSRs) use, and improve resistance to molten salt infiltration of the matrix graphite for fuel elements. Mesocarbon microbeads (MCMB) densified matrix graphite A3-3 (MDG) was prepared by a quasi-isostatic pressure process. After densification by MCMBs with average particle sizes of 2, 10, and 16 ㎛, the pore diameter of A3-3 decreased from 924 nm to 484 nm, 532 nm, and 778 nm, respectively. Through scanning electron microscopy, the cross-section energy spectrum and time-of-flight secondary ion mass spectrometry, resistance levels of the matrix graphite to molten salt infiltration were analyzed. The results demonstrate that adding a certain proportion of MCMB powders can improve the anti-infiltration ability of A3-3. Meanwhile, the closer the particle size of MCMB is to the pore diameter of A3-3, the smaller the average pore diameter of MDG and the greater the densification. As a matrix graphite of fuel elements in MSR was involved, the thermal and mechanical properties of matrix graphite MDG were also studied. When densified by the MCMB matrix graphite, MDGs can meet the molten salt anti-infiltration requirements for MSR operation.

Production and Optimization of a Kiwi Pectin Methylesterase Inhibitor in Pichia pastoris GS115

Qian Liu,Wentao Xu,Shiwen Han,Dongyan Cao,Xiaoyun He,Kunlun Huang,Xiaohong Mei 한국식품과학회 2014 Food Science and Biotechnology Vol.23 No.6

Gene sequence coding of a kiwi pectin methylesteraseinhibitor was optimized, synthesized, and expressedin Pichia pastoris GS115 based on P. pastoris preferredcodon usage. The expression level of the recombinantprotein (kwPMEI) increased by 89.74% after codonoptimization. Expression conditions of recombinant strainswere optimized. The highest production of kwPMEI wasachieved using 0.8% sorbitol (added every 24 h), 0.05%oleic acid (added at the beginning of induction), and 0.5%methanol (added every 12 h). kwPMEI was purified usingNi2+ chelating affinity chromatography and 17 mg of theprotein was harvested from 60 mL of a culture supernatant. Activity analysis showed that kwPMEI efficiently inhibitedthe activity of different plant PMEs. High expression levelsand purification of kwPMEI will promote applications infruit and vegetable juices.

Safety and antifatigue effect of Korean Red Ginseng: a randomized, double-blind, and placebo-controlled clinical trial

Zhang, Li,Chen, Xiaoyun,Cheng, Yanqi,Chen, Qilong,Tan, Hongsheng,Son, Dongwook,Chang, Dongpill,Bian, Zhaoxiang,Fang, Hong,Xu, Hongxi The Korean Society of Ginseng 2019 Journal of Ginseng Research Vol.43 No.4

Background: Korean Red Ginseng (KRG) is widely used for strengthening the immune system and fighting fatigue, especially in people with deficiency syndrome. However, there is concern that the long-term application or a high dose of KRG can cause "fireness" (上火 in Chinese) because of its "dryness" (燥性 in Chinese). The aim of this study was to assess the safety and efficacy of a 4-week treatment with KRG in participants with deficiency syndrome. Methods: This was a 4-week, randomized, double-blind, placebo-controlled clinical trial. A total of 180 Chinese participants were randomly allocated to three groups: placebo control group, participants were given a placebo, 3.6 g/d; KRG 1.8 g and 3.6 g groups. The primary outcomes were the changes in fireness and safety evaluation (adverse events, laboratory tests, and electrocardiogram). The secondary outcomes were the efficacy of KRG on fatigue, which include the following: traditional Chinese medicine (TCM) symptom scale and fatigue self-assessment scale. Results: Of the 180 patients, 174 completed the full study. After 4 weeks of KRG treatment, the Fire-heat symptoms score including Excess fire-heat score and Deficient fire-heat score showed no significant change as compared with placebo treatment, and no clinically significant changes in any safety parameter were observed. Based on the TCM syndrome score and fatigue self-assessment score, TCM symptoms and fatigue were greatly improved after treatment with KRG, which showed a dose- and time-dependent effect. The total effective rate was also significantly increased in the KRG groups. Conclusion: Our study revealed that KRG has a potent antifatigue effect without significant adverse effects in people with deficiency syndrome. Although a larger sample size and longer treatment may be required for a more definite conclusion, this clinical trial is the first to disprove the common conception of "fireness" related to KRG.

Direct protection of cultured neurons from ischemia-like injury by minocycline

Wendy C. Huang,Yanli Qiao,Lijun Xu,Rachid Kacimi,Xiaoyun Sun,Rona G. Giffard,Midori A. Yenari 대한해부학회 2010 Anatomy & Cell Biology Vol.43 No.4

Minocycline, a tetracycline antibiotic, is now known to protect cells via an anti-inflammatory mechanism. We further explored this effect using an in vitro model of ischemia-like injury to neurons. Coculturing neurons with microglia, the brain’s resident immune cell, modestly increased cell death due to oxygen and glucose deprivation (OGD), compared to neurons alone. Treatment of cocultures with minocycline decreased cell death to a level significantly lower than that of neurons alone. Treatment of cocultures with minocycline or inhibitors of various immune mediators, also led to decreased cell death. Importantly, treatment of neuron cultures without added microglia with these same inhibitors of tissue plasminogen activator, matrix metalloproteinases, TNF-alpha and inducible nitric oxide synthase as well as minocycline also led to decreased cell death. Thus, anti-inflammatory treatments appear to be directly protective of neurons from in vitro ischemia.

Drug-loaded microbubble delivery system to enhance PD-L1 blockade immunotherapy with remodeling immune microenvironment

Zheng Jun,Huang Ju,Zhang Liang,Wang Mengna,Xu Lihong,Dou Xiaoyun,Leng Xiaojing,Fang Mingxiao,Sun Yang,Wang Zhigang 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Although programmed cell death protein 1 (PD-1)/ programmed cell death-ligand protein 1 (PD-L1) checkpoint blockade immunotherapy demonstrates great promise in cancer treatment, poor infiltration of T cells resulted from tumor immunosuppressive microenvironment (TIME) and insufficient accumulation of anti-PD-L1 (αPD-L1) in tumor sites diminish the immune response. Herein, we reported a drug-loaded microbubble delivery system to overcome these obstacles and enhance PD-L1 blockade immunotherapy.Docetaxel (DTX) and imiquimod (R837)-loaded microbubbles (RD@MBs) were synthesized via a typical rotary evaporation method combined with mechanical oscillation. The targeted release of drugs was achieved by using the directional "bursting" capability of ultrasound-targeted microbubble destruction (UTMD) technology. The antitumor immune response by RD@MBs combining αPD-L1 were evaluated on 4T1 and CT26 tumor models.The dying tumor cells induced by DTX release tumor-associated antigens (TAAs), together with R837, promoted the activation, proliferation and recruitment of T cells. Besides, UTMD technology and DTX enhanced the accumulation of αPD-L1 in tumor sites. Moreover, RD@MBs remolded TIME, including the polarization of M2-phenotype tumor-associated macrophages (TAMs) to M1-phenotype, and reduction of myeloid-derived suppressor cells (MDSCs). The RD@MBs + αPD-L1 synergistic therapy not only effectively inhibited the growth of primary tumors, but also significantly inhibited the mimic distant tumors as well as lung metastases.PD-L1 blockade immunotherapy was enhanced by RD@MBs delivery system.

Polymethoxylated Flavone Extracts from Citrus Peels for Use in the Functional Food and Nutraceutical Industry

Xiaolin Yao,Siyi Pan,Chunhong Duan,Fang Yang,Gang Fan,Xinrong Zhu,Shuzhen Yang,Xiaoyun Xu 한국식품과학회 2009 Food Science and Biotechnology Vol.18 No.5

Polymethoxylated flavones (PMFs) extracted from Citrus sinensis ‘Jincheng’ peel were characterized by chromatographic and spectroscopic techniques. Seven individual PMF were identified. 3, 3’, 4’, 5, 6, 7-hexamethoxyflavone (HEX), nobiletin (NOB), heptamethoxyflavone (HEP), 5-demethylnobiletin (DN), and tangeretin (TAN) were characterized through electrospray ionization mass spectrometry (ESI-MS) in positive mode of protonated molecular ions [M+H]?, the diagnostic fragment ions, together with the UV-Vis spectra and high performance liquid chromatography (HPLC) elution order from literature data. Sinensetin (SIN) and tetramethyl-O-scutellarein (SCU) were isolated and identified through their MS, ¹H nuclear magnetic resonance (NMR) and UV-Vis spectral studies. The levels of PMFs in peels from different cultivars of citrus fruits grown in China were determined for the first time. The results showed that C. aurantium ‘Bitter orange’ peel was the most promising variety for HEP. C. sinensis peel was a good source for SIN and SCU.