Publications by authors named "Yifeng Zhang"

272 Publications

Insights into the impact of polyethylene microplastics on methane recovery from wastewater via bioelectrochemical anaerobic digestion.

Water Res 2022 Aug 9;221:118844. Epub 2022 Jul 9.

Department of Environmental and Resource Engineering, Technical University of Denmark, Lyngby DK-2800, Denmark. Electronic address:

Bioelectrochemical anaerobic digestion (BEAD) is a promising next-generation technology for simultaneous wastewater treatment and bioenergy recovery. While knowledge on the inhibitory effect of emerging pollutants, such as microplastics, on the conventional wastewater anaerobic digestion processes is increasing, the impact of microplastics on the BEAD process remains unknown. This study shows that methane production decreased by 30.71% when adding 10 mg/L polyethylene microplastics (PE-MP) to the BEAD systems. The morphology of anaerobic granular sludge, which was the biocatalysts in the BEAD, changed with microbes shedding and granule crack when PE-MP existed. Additionally, the presence of PE-MP shifted the microbial communities, leading to a lower diversity but higher richness and tight clustering. Moreover, fewer fermentative bacteria, acetogens, and hydrogenotrophic methanogens (BEAD enhanced) grew under PE-MP stress, suggesting that PE-MP had an inhibitory effect on the methanogenic pathways. Furthermore, the abundance of genes relevant to extracellular electron transfer (omcB and mtrC) and methanogens (hupL and mcrA) decreased. The electron transfer efficiency reduced with extracellular cytochrome c down and a lower electron transfer system activity. Finally, phylogenetic investigation of communities by reconstruction of unobserved states analysis predicted the decrease of key methanogenic enzymes, including EC 1.1.1.1 (Alcohol dehydrogenase), EC 1.2.99.5 (Formylmethanofuran dehydrogenase), and EC 2.8.4.1 (Coenzyme-B sulfoethylthiotransferase). Altogether, these results provide insight into the inhibition mechanism of microplastics in wastewater methane recovery and further optimisation of the BEAD process.
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http://dx.doi.org/10.1016/j.watres.2022.118844DOI Listing
August 2022

Embryonic cardio-respiratory impairments in rainbow trout (Oncorhynchus mykiss) following exposure to hydraulic fracturing flowback and produced water.

Environ Pollut 2022 Aug 5;310:119886. Epub 2022 Aug 5.

Department of Biological Sciences, University of Alberta, Edmonton, AB, T6G 2E9, Canada; NRC- University of Alberta Nanotechnology Initiative, Edmonton, AB, T6G 2M9, Canada.

During hydraulic fracturing, wastewaters - termed flowback and produced water (FPW) - are created as a by-product during hydrocarbon extraction. Given the large volumes of FPW that a single well can produce, and the history of FPW release to surface water bodies, it is imperative to understand the hazards that hydraulic fracturing and FPW pose to aquatic biota. Using rainbow trout embryos as model organisms, we investigated impacts to cardio-respiratory system development and function following acute (48 h) and sub-chronic (28-day) FPW exposure by examining occurrences of developmental deformities, rates of embryonic respiration (MO), and changes in expression of critical cardiac-specific genes. FPW-exposed embryos had significantly increased rates of pericardial edema, yolk-sac edema, and tail/trunk curvatures at hatch. Furthermore, when exposed at three days post-fertilization (dpf), acute 5% FPW exposures significantly increased embryonic MO through development until 15 dpf, where a switch to significantly reduced MO rates was subsequently recorded. A similar trend was observed during sub-chronic 1% FPW exposures. Interestingly, at certain specific developmental timepoints, previous salinity exposure seemed to affect embryonic MO; a result not previously observed. Following acute FPW exposures, embryonic genes for cardiac development and function were significantly altered, although at termination of sub-chronic exposures, significant changes to these same genes were not found. Together, our evidence of induced developmental deformities, modified embryonic MO, and altered cardiac transcript expression suggest that cardio-respiratory tissues are toxicologically targeted following FPW exposure in developing rainbow trout. These results may be helpful to regulatory bodies when developing hazard identification and risk management protocols concerning hydraulic fracturing activities.
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http://dx.doi.org/10.1016/j.envpol.2022.119886DOI Listing
August 2022

Cometabolic biodegradation system employed subculturing photosynthetic bacteria: A new degradation pathway of 4-chlorophenol in hypersaline wastewater.

Bioresour Technol 2022 Jul 22;361:127670. Epub 2022 Jul 22.

College of Environment, Zhejiang University of Technology, 18 Chaowang Road, Hangzhou, Zhejiang 310014, PR China. Electronic address:

4-chlorophenol (4-CP) as a toxic persistent pollutant is quite difficult treatment by using traditional biological processes. Herein, photosynthetic bacteria (PSB) driven cometabolic biodegradation system associated with exogeneous carbon sources (e.g., sodium acetate) has been demonstrated as an effective microbial technique. The biodegradation rate (r) can be at 0.041 d with degradation efficiency of 93% in 3094 lx. Through the study of subculturing PSB in absence of NaCl, it was found that 50% inoculation time can be saved but keeping a similar 4-CP biodegradation efficiency in scale-up salinity system. A new plausible biodegradation pathway for 4-CP in 4th G PSB cometabolic system is proposed based on the detected cyclohexanone generation followed by ring opening. It is probably ascribed to the increasement of Firmicutes and Bacteroidetes at phyla level classified based on microbial community. This study contributes to a new insight into cometabolic technology for chlorophenol treatment in industrial hypersaline wastewater.
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http://dx.doi.org/10.1016/j.biortech.2022.127670DOI Listing
July 2022

The potential of a nomogram combined PI-RADS v2.1 and contrast-enhanced ultrasound (CEUS) to reduce unnecessary biopsies in prostate cancer diagnostics.

Br J Radiol 2022 Jul 25:20220209. Epub 2022 Jul 25.

Center of Minimally Invasive Treatment for Tumor, Department of Medical Ultrasound, Shanghai Tenth People's Hospital, School of Medicine, Tongji University, Shanghai, China.

Objectives: To develop a nomogram prediction model based on Prostate Imaging Reporting and Data System version 2.1 (PI-RADS v2.1) and contrast-enhanced ultrasound (CEUS) for predicting prostate cancer (PCa) and clinically significant prostate cancer (csPCa) in males with prostate-specific antigen (PSA) 4-10 ng ml to avoid unnecessary biopsy.

Methods: A total of 490 patients who underwent prostate biopsy for PSA 4-10 ng ml were enrolled and randomly divided into a pilot cohort (70%) and a validation cohort (30%). Univariate and multivariate logistic regression models were constructed to select potential predictors of PCa and csPCa, and a nomogram was created. The area under receiver operating characteristic (ROC) curve (AUC) was calculated, and compared using DeLong's test. The diagnostic performance and unnecessary biopsy rate of the nomogram prediction model were also assessed. Hosmer-Lemeshow Goodness-of-fit test was employed to test for model fitness.

Results: The multivariate analysis revealed that features independently associated with PCa and csPCa were age, PI-RADS score and CEUS manifestations. Incorporating these factors, the nomogram achieved good discrimination performance of AUC 0.843 for PCa, 0.876 for csPCa in the pilot cohort, and 0.818 for PCa, 0.857 for csPCa in the validation cohort, respectively, and had well-fitted calibration curves. And the diagnostic performance of the nomogram was comparable to the model including all the parameters ( > 0.05). Besides, the nomogram prediction model yielded meaningful reduction in unnecessary biopsy rate (from 74.8 to 21.1% in PCa, and from 83.7 to 5.4% in csPCa).

Conclusions: The nomogram prediction model based on age, PI-RADS v2.1 and CEUS achieved an optimal prediction of PCa and csPCa. Using this model, the PCa risk for an individual patient can be estimated, which can lead to a rational biopsy choice.

Advances In Knowledge: This study gives an account of improving pre-biopsy risk stratification in males with "gray zone" PSA level through PI-RADS v2.1 and CEUS.
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http://dx.doi.org/10.1259/bjr.20220209DOI Listing
July 2022

Overexpression of , , and Regulates Celastrol Accumulation in Cambial Meristematic Cells and Dedifferentiated Cells.

Front Plant Sci 2022 1;13:926715. Epub 2022 Jul 1.

Beijing Shijitan Hospital, Capital Medical University, Beijing, China.

Squalene synthase (SQS), squalene epoxidase (SE), and oxidosqualene cyclase (OSC) are encoding enzymes in downstream biosynthetic pathway of triterpenoid in plants, but the relationship between three genes and celastrol accumulation in still remains unknown. Gene transformation system in plant can be used for studying gene function rapidly. However, there is no report on the application of cambial meristematic cells (CMCs) and dedifferentiated cells (DDCs) in genetic transformation systems. Our aim was to study the effects of individual overexpression of , , and on terpenoid accumulation and biosynthetic pathway related gene expression through CMCs and DDCs systems. Overexpression vectors of , , and were constructed by Gateway technology and transferred into CMCs and DDCs by gene gun. After overexpression, the content of celastrol was significantly increased in CMCs compared with the control group. However, there was no significant increment of celastrol in DDCs. Meanwhile, the relative expression levels of , , , and terpenoid biosynthetic pathway related genes were detected. The relative expression levels of , , and were increased compared with the control group in both CMCs and DDCs, while the pathway-related genes displayed different expression trends. Therefore, it was verified in CMCs that overexpression of , , and increased celastrol accumulation and had different effects on the expression of related genes in terpenoid biosynthetic pathway, laying a foundation for further elucidating the downstream biosynthetic pathway of celastrol through CMCs system.
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http://dx.doi.org/10.3389/fpls.2022.926715DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9284119PMC
July 2022

Different soil particle size changes the N retention in soil and N utilization by maize.

Sci Total Environ 2022 Jul 2;843:157133. Epub 2022 Jul 2.

College of Resource and Environmental Science, Jilin Agricultural University, Changchun, Jilin Province 130118, China.

Improving soil structure is key to improving soil quality and nitrogen utilization efficiency (NUE) in global cropping systems. Soil sieving is a direct means of dividing soil activity into components with different practical functional significance. In order to have a more intuitive understanding of nutrient turnover and NUE under different soil particle sizes, we identified the key soil particle sizes that affect N cycling in cropping systems. An in-situ field experiment was conducted in Mollisol for three years using the N isotope tracer technique to examine the effect of soil structure on maize growth, nutrient uptake, and NUE. We artificially destructed the soil structure by sieving it into four particle size classes: (i) unsieved soil (CK), (ii) <0.5 mm size (A), (iii) 0.5-2 mm size (B), and (iv) 2-5 mm size (C). Then each year, the physical properties of the soil, N loss and retention rate (NRR), the NUE, N absorption, and distribution, as well as maize growth and yield, were measured. The results showed that the 0.5-2 mm size (B) and 2-5 mm size (C) improved soil physical properties and increased the uptake of N by maize (especially in the leaves and grains), thereby increasing maize yield. The B and C particle sizes had lower soil NRR and higher alkaline hydrolysable N content than the other treatments in the depth. We concluded that the B sieving treatment is the key aggregate fraction to increasing maize NUE and yield and minimizing the negative effects on soil N retention capacity. Furthermore, the B treatment is key to affecting crop nutrient absorption and utilization.
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http://dx.doi.org/10.1016/j.scitotenv.2022.157133DOI Listing
July 2022

Emerging nanobiotechnology-encoded relaxation tuning establishes new MRI modes to localize, monitor and predict diseases.

J Mater Chem B 2022 Jun 30. Epub 2022 Jun 30.

Central Laboratory and Ultrasound Research and Education Institute, Shanghai Tenth People's Hospital, Tongji University School of Medicine, No. 301 Yan-chang-zhong Road, Shanghai 200072, China.

Magnetic resonance imaging (MRI) is one of the most important techniques in the diagnosis of many diseases including cancers, where contrast agents (CAs) are usually necessary to improve its precision and sensitivity. Previous MRI CAs are confined to the signal-to-noise ratio (SNR) elevation of lesions for precisely localizing lesions. As nanobiotechnology advances, some new MRI CAs or nanobiotechnology-enabled MRI modes have been established to vary the longitudinal or transverse relaxation of CAs, which are harnessed to detect lesion targets, monitor disease evolution, predict or evaluate curative effect, These distinct cases provide unexpected insights into the correlation of the design principles of these nanobiotechnologies and corresponding MRI CAs with their potential applications. In this review, first, we briefly present the principles, classifications and applications of conventional MRI CAs, and then elucidate the recent advances in relaxation tuning the development of various nanobiotechnologies with emphasis on the design strategies of nanobiotechnology and the corresponding MRI CAs to target the tumor microenvironment (TME) and biological targets or activities in tumors or other diseases. In addition, we exemplified the advantages of these strategies in disease theranostics and explored their potential application fields. Finally, we analyzed the present limitations, potential solutions and future development direction of MRI after its combination with nanobiotechnology.
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http://dx.doi.org/10.1039/d2tb00600fDOI Listing
June 2022

Mechanistic analysis for the origin of diverse diterpenes in .

Acta Pharm Sin B 2022 Jun 22;12(6):2923-2933. Epub 2022 Feb 22.

Beijing Shijitan Hospital, Capital Medical University, Beijing 100038, China.

is a valuable medicinal plant rich in biologically active diterpenoids, but there are few studies on the origins of these diterpenoids in its secondary metabolism. Here, we identified three regions containing tandemly duplicated diterpene synthase genes on chromosomes (Chr) 17 and 21 of and obtained 11 diterpene synthases with different functions. We further revealed that these diterpene synthases underwent duplication and rearrangement at approximately 2.3-23.7 million years ago (MYA) by whole-genome triplication (WGT), transposon mediation, and tandem duplication, followed by functional divergence. We first demonstrated that four key amino acids in the sequences of TwCPS3, TwCPS5, and TwCPS6 were altered during evolution, leading to their functional divergence and the formation of diterpene secondary metabolites. Then, we demonstrated that the functional divergence of three TwKSLs was driven by mutations in two key amino acids. Finally, we discovered the mechanisms of evolution and pseudogenization of miltiradiene synthases in and elucidated that the new function in TwMS1/2 from the terpene synthase (TPS)-b subfamily was caused by progressive changes in multiple amino acids after the WGT event. Our results provide key evidence for the formation of diverse diterpenoids during the evolution of secondary metabolites in .
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http://dx.doi.org/10.1016/j.apsb.2022.02.013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9214345PMC
June 2022

Efficient recovery of dissolved Fe(II) from near neutral pH Fenton via microbial electrolysis.

J Hazard Mater 2022 08 20;436:129196. Epub 2022 May 20.

Department of Environmental Engineering, Technical University of Denmark, DK-2800 Lyngby, Denmark.

Fe(II) regeneration from ferric sludge via a biocathode and citrate system has recently been proposed to avoid iron-sludge accumulation and iron consumption in homogeneous Fenton treatments. However, poor regeneration rate of Fe(II) from ferric sludge at a near-neutral pH, without an iron-complexing agent, limited its wider practical application. Here, a biocathode augmented with Geobacter sulfurreducens hosted by a microbial electrolysis cell was developed to efficiently regenerate dissolved Fe(II) from ferric sludge at near-neutral pH levels, without using iron-complexing agents. In the Geobacter sulfurreducens-rich biocathode without complexing agents, the regeneration rate of dissolved Fe(II) increased three-fold compared with the biocathode before inoculating Geobacter sulfurreducens. The highest concentration of dissolved Fe(II) increased from 45 mg Fe/L to 199 mg Fe/L at pH 6 when 0.5 V of voltage was applied. Furthermore, 84 mg Fe/L of dissolved Fe(II) was successfully regenerated from ferric sludge during the 123 days' operation of flow-through biocathode. Finally, the regenerated Fe(II) solution without organic matters was successfully applied in a near-neutral pH Fenton treatment to remove recalcitrant pollutants. This Geobacter sulfurreducens-rich biocathode, with its low chemical consumption, high regeneration rate and feasibility for continuous flow operation, offers a more efficient method to realize iron-free in homogeneous Fenton treatments.
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http://dx.doi.org/10.1016/j.jhazmat.2022.129196DOI Listing
August 2022

Key Glycosyltransferase Genes of : Identification and Engineering Yeast Construction of Rare Ginsenosides.

ACS Synth Biol 2022 07 10;11(7):2394-2404. Epub 2022 Jun 10.

School of Traditional Chinese Medicine, Capital Medical University, Beijing 100069, People's Republic of China.

is one of the most famous valuable medical plants in China, and its broad application in clinical treatment has an inseparable relationship with the active molecules, ginsenosides. Ginsenosides are glycoside compounds that have varied structures for the diverse sugar chain. Although extensive work has been done, there are still unknown steps in the biosynthetic pathway of ginsenosides. Here, we screened candidate glycosyltransferase genes based on the previous genome and transcriptome data of and cloned the full length of 27 UGT genes successfully. Among them, we found that UGT33 could catalyze different ginsenoside substrates to produce higher polarity rare ginsenosides by extending the sugar chain. We further analyzed the enzymatic kinetics and predicted the catalytic mechanism of UGT33 by simulating molecular docking. After that, we reconstructed the biosynthetic pathway of rare ginsenoside Rg and gypenoside LXXV in yeast. By combining the Golden Gate method and overexpressing the UDPG biosynthetic genes, we further improved the yield of engineering yeast strain. Finally, the shake-flask culture yield of Rg reached 51 mg/L and the fed-batch fermentation yield of gypenoside LXXV reached 94.5 mg/L, which was the first and highest record.
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http://dx.doi.org/10.1021/acssynbio.2c00094DOI Listing
July 2022

Pyrogenic carbon facilitated microbial extracellular electron transfer in electrogenic granular sludge via geobattery mechanism.

Water Res 2022 Jul 16;220:118618. Epub 2022 May 16.

College of Chemical and Biological Engineering, Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Zhejiang University, Hangzhou 310027, China. Electronic address:

Electroactive pyrogenic carbon (PC) is an intriguing candidate for realizing the ambitious goals of large-scale applications of microbial electrochemical technologies (METs). In this study, PC was employed to promote the extracellular electron transfer (EET) within the electrogenic granular sludge (EGS) by acting as an electron conduit. The pecan shell-derived PC prepared at three temperatures (600, 800, and 1000 ˚C) contained rich oxygenated-functional moieties (mainly quinone) on the surface, endowing a good electron transfer capacity (EEC). The maximum current density (J) of EGS with PC amendment outperformed the control EGS without PC amendment, i.e., 100-132 times higher than J of EGS in the absence of PC. Among various pyrolysis temperatures, the PC derived from 600 ˚C produced the highest J (0.40 A/ m), 0.67-times, and 0.33-times higher than that of PC derived from 800 and 1000 ˚C, respectively. Furthermore, more polysaccharides were secreted in extracellular polymeric substance with PC amendments. The microbial community analysis demonstrated that the PC favored the growth of electroactive bacteria over methanogens. The metabolic pathway revealed that PC induced more functional enzymes in the quinone biosynthesis and cytochrome c and heme synthesis, resulting in an enhanced EET. The EEC of PC was responsible for the EET enhancement effect via PC acting as a geobattery to wire up the EGS and electrodes. Overall, this study pinpoints the finding of PC role in a mixed electroactive biofilm and provides a wide scenario of the PC applications in MET at large scales.
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http://dx.doi.org/10.1016/j.watres.2022.118618DOI Listing
July 2022

Renewable energy demand, financial reforms, and environmental quality in West Africa.

Environ Sci Pollut Res Int 2022 May 14. Epub 2022 May 14.

School of Business, Nanjing University of Information Science & Technology, Pukou District, Nanjing, 210044, Jiangsu, China.

Sustainable Development Goal (SDG-7) stipulates the need for clean energy, reduced carbon dioxide emissions, prevention of environmental degradation, promotion of biodiversity, and ecosystem preservation. Toward achieving these goals, this study provides new evidence on the causal link between renewable energy demand, financial reforms, economic growth, foreign direct investment, and environmental quality among emerging West African economies. The study adopted the fully modified ordinary least squares, dynamic ordinary least squares, pooled mean group estimation, and Granger causality test for its analysis. It was found that renewable energy demand has been favorable to the environmental health of West African economies. Also, financial reforms made within the region contributed to increasing the ecological footprints of the region. Direct investments from foreigners showed encouraging results as they improved the quality of the environment. We also found a unidirectional causality from ecological footprints to renewable energy demand and financial reforms but a bidirectional relationship with economic growth and foreign direct investment. Moreover, it was evident that ecological footprints Granger cause financial reforms and economic growth but not vice versa. Policy recommendations outlined encourage governments and policymakers to embark on intensive clean energy technologies and effective green financial reforms to help achieve Sustainable Development Goals.
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http://dx.doi.org/10.1007/s11356-022-20692-2DOI Listing
May 2022

An overview of nanomaterial-based novel disinfection technologies for harmful microorganisms: Mechanism, synthesis, devices and application.

Sci Total Environ 2022 Sep 4;837:155720. Epub 2022 May 4.

College of Environment, Zhejiang University of Technology (ZJUT), Hangzhou 310014, China. Electronic address:

Harmful microorganism (e.g., new coronavirus) based infection is the most important security concern in life sciences and healthcare. This article aims to provide a state-of-the-art review on the development of advanced technology based on nanomaterial disinfection/sterilization techniques (NDST) for the first time including the nanomaterial types, disinfection techniques, bactericidal devices, sterilization products, and application scenarios (i.e., water, air, medical healthcare), with particular brief account of bactericidal behaviors referring to varied systems. In this emerging research area spanning the years from 1998 to 2021, total of ~200 publications selected for the type of review paper and research articles were reviewed. Four typical functional materials (namely type of metal/metal oxides, S-based, C-based, and N-based) with their development progresses in disinfection/sterilization are summarized with a list of synthesis and design. Among them, the widely used silver nanoparticles (AgNPs) are considered as the most effective bacterial agents in the type of nanomaterials at present and has been reported for inactivation of viruses, fungi, protozoa. Some methodologies against (1) disinfection by-products (DBPs) in traditional sterilization, (2) noble metal nanoparticles (NPs) agglomeration and release, (3) toxic metal leaching, (4) solar spectral response broadening, and (5) photogenerated e/h pairs recombination are reviewed and discussed in this field, namely (1) alternative techniques and nanomaterials, (2) supporter anchoring effect, (3) nonmetal functional nanomaterials, (4) element doping, and (5) heterojunction constructing. The feasible strategies in the perspective of NDST are proposed to involve (1) non-noble metal disinfectors, (2) multi-functional nanomaterials, (3) multi-component nanocomposite innovation, and (4) hybrid techniques for disinfection/sterilization system. It is promising to achieve 100% bactericidal efficiency for 10 CFU/mL within a short time of less than 30 min.
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http://dx.doi.org/10.1016/j.scitotenv.2022.155720DOI Listing
September 2022

Nitrogen and phosphorous recycling from human urine by household electrochemical fixed bed in sparsely populated regions.

Water Res 2022 Jun 15;218:118467. Epub 2022 Apr 15.

Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100085, China. Electronic address:

Decentralized treatment of human urine in sparsely populated regions could avoid the problem of sewage collection in traditionally centralized treatment schemes and simultaneously utilize the recovered N/P fertilizer in-situ to nurture gardens. Herein, an integrated electrochemical fixed bed packed with divided magnesite and carbon zones was constructed for the pretreatment of human urine, followed by the recovery of 95.0% NH and 85.8% PO via struvite precipitation and NH volatilization as well as the on-site employment of the produced struvite as fertilizer. In the process, the acid/base zones created by electrochemical water splitting dissolved the magnesite filler as the Mg source of struvite, further creating an ideal pH environment for struvite precipitation and NH volatilization in the effluent. Without the need to control solution pH by chemical addition, the system can resist impacts from changes in water quality by adjustment of the current density and flow rate, indicating its great potential for automatic operation. Life cycle assessment indicated that the on-site employment of produced struvite avoids the long-distance fertilizer transportation required for fertilization, thus reducing carbon emission by a hundred million tons per year if the household facility is driven by clean electricity.
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http://dx.doi.org/10.1016/j.watres.2022.118467DOI Listing
June 2022

Biochemical characterization of an engineered bifunctional xylanase/feruloyl esterase and its synergistic effects with cellulase on lignocellulose hydrolysis.

Bioresour Technol 2022 Jul 27;355:127244. Epub 2022 Apr 27.

College of Food Science, Shenyang Agricultural University, Shenyang, China; College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang, China. Electronic address:

Herein, the xylanase and feruloyl esterase domains of the xylanase/feruloyl esterase bifunctional enzyme (Xyn-Fae) from Prevotella ruminicola 23 were identified using N- and C-terminal truncation mutagenesis. In addition, a novel and more efficient xylanase/feruloyl esterase bifunctional enzyme XynII-Fae was constructed, and its synergistic action with a commercial cellulase for lignocellulose hydrolysis was studied. When 40% cellulase was replaced by XynII-Fae, the production of reducing sugars increased by 65% than that with the cellulase alone, and the conversions of xylan and glucan were increased by 125.1% and 54.3%, respectively. When 80% cellulase was substituted by XynII-Fae, up to 43.5 μg/mL ferulic acid and 418.7 μg/mL acetic acid were obtained. The XynII-Fae could also accelerate the hydrolysis of wheat straw and sugarcane bagasse with commercial cellulase. These results indicated that the synergistic action of XynII-Fae with cellulase could dramatically improve the hydrolysis efficiency of lignocellulose, showing the great potential for industrial applications.
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http://dx.doi.org/10.1016/j.biortech.2022.127244DOI Listing
July 2022

Novel fabricated low-cost hybrid polyacrylonitrile/polyvinylpyrrolidone coated polyurethane foam (PAN/[email protected]) membrane for the decolorization of cationic and anionic dyes.

J Environ Manage 2022 Aug 25;315:115128. Epub 2022 Apr 25.

Fabrication Technology Research Department, Advanced Technology and New Materials Research Institute (ATNMRI), City of Scientific Research and Technological Applications, (SRTA-City), New Borg El-Arab City, Alexandria, 21934, Egypt; Chemical and Petrochemicals Engineering Department, Engineering Faculty, Egypt-Japan University of Science and Technology, New BorgEl-Arab City, Alexandria, 21934, Egypt.

Dyes are recalcitrait organic pollutants threatening the aquatic environment and human health. In the present study, a novel low-cost hybrid membrane was fabricated by coating polyurethane foam (PUF) with polyacrylonitrile/polyvinylpyrrolidone (PAN/PVP) via phase inversion technique from casting solutions consisting of PAN and PVP with Dimethyl formamide (DMF) and applied for removal of cationic (Methylene Blue (MB)) and anionic (Methyl Orange (MO)) dyes from aqueous solutions. The as-prepared membrane was first characterized by Scan Electron Microscope (SEM), Fourier Transform Infrared (FTIR), Energy Dispersive Spectrometry (EDS), etc. Then, batch experiments were conducted to optimize the adsorption conditions, including contact time, adsorbent dose, dyes concentration, and pH. The dye removal results fitted with pseudo first and second-order kinetics; Langmuir, Freundlich, and Temkin isotherms' models. The maximum dye decolorization was approximately 97% and 95% within 60 and 120 min using 0.5 and 1 g of the fabricated composite for MB and MO, respectively. The kinetic studies showed rapid sorption dynamics following a second-order kinetic model. In addition, dye adsorption equilibrium data fitted well to the Freundlich isotherm with monolayer maximum adsorption capacity of 6.356 and 3.321 mg/g for MO and MB dye, respectively. Thus, the novel hybrid membrane is promising as a cheap and efficient adsorbent for the removal of both cationic and anionic dyes from wastewater. The current study demonstrated a new avenue to achieve efficient management of dyes in aquatic environments.
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http://dx.doi.org/10.1016/j.jenvman.2022.115128DOI Listing
August 2022

ABO genotype alters the gut microbiota by regulating GalNAc levels in pigs.

Nature 2022 06 27;606(7913):358-367. Epub 2022 Apr 27.

National Key Laboratory for Swine Genetic Improvement and Production Technology, Ministry of Science and Technology of China, Jiangxi Agricultural University, Nanchang, PR China.

The composition of the intestinal microbiome varies considerably between individuals and is correlated with health. Understanding the extent to which, and how, host genetics contributes to this variation is essential yet has proved to be difficult, as few associations have been replicated, particularly in humans. Here we study the effect of host genotype on the composition of the intestinal microbiota in a large mosaic pig population. We show that, under conditions of exacerbated genetic diversity and environmental uniformity, microbiota composition and the abundance of specific taxa are heritable. We map a quantitative trait locus affecting the abundance of Erysipelotrichaceae species and show that it is caused by a 2.3 kb deletion in the gene encoding N-acetyl-galactosaminyl-transferase that underpins the ABO blood group in humans. We show that this deletion is a ≥3.5-million-year-old trans-species polymorphism under balancing selection. We demonstrate that it decreases the concentrations of N-acetyl-galactosamine in the gut, and thereby reduces the abundance of Erysipelotrichaceae that can import and catabolize N-acetyl-galactosamine. Our results provide very strong evidence for an effect of the host genotype on the abundance of specific bacteria in the intestine combined with insights into the molecular mechanisms that underpin this association. Our data pave the way towards identifying the same effect in rural human populations.
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http://dx.doi.org/10.1038/s41586-022-04769-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9157047PMC
June 2022

A flexible tissue-carbon nanocoil-carbon nanotube-based humidity sensor with high performance and durability.

Nanoscale 2022 May 16;14(18):7025-7038. Epub 2022 May 16.

School of Physics, Dalian University of Technology, No. 2 Linggong Road, Ganjingzi District, Dalian 116024, P. R. China.

A flexible humidity sensor based on a tissue-carbon nanocoil (CNC)-carbon nanotube (CNT) composite has been investigated. Taking advantage of the excellent water absorption of tissue and the electrical sensitivity of CNCs/CNTs to humidity, this humidity sensor obtains outstanding humidity sensing performance, including a wide sensing range of 10-90% RH, a maximum response value of 492% (Δ/) at 90% RH, a maximum sensitivity of 6.16%/% RH, a good long-time stability of more than 7 days, a high humidity resolution accuracy of less than 1% RH and a fast response time of 275 ms. Furthermore, the sensor also exhibits robust bending (with a curvature of 0.322 cm) and folding (up to 500 times) durability, and after being made into a complex "thousand paper crane" shape it still provides stable humidity sensing performance. As a proof of concept, this humidity sensor demonstrates excellent responsivity to human breath monitoring, non-contact fingertip humidity detection, water boiling detection and air humidity monitoring, indicating great potential in the fields of wearable devices, weather forecasting systems and other intelligent humidity monitoring devices.
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http://dx.doi.org/10.1039/d2nr00027jDOI Listing
May 2022

Novel biocatalytic strategy of levan: His-ELP-intein-tagged protein purification and biomimetic mineralization.

Carbohydr Polym 2022 Jul 26;288:119398. Epub 2022 Mar 26.

College of Food Science, Shenyang Agricultural University, Shenyang, China; College of Biosciences and Biotechnology, Shenyang Agricultural University, Shenyang, China. Electronic address:

Here a versatile fusion tag composed of His-tag, intein, and elastin-like polypeptide (ELP) tag was prepared for the first time to be fused with levansucrase SacB to construct a recombinant His-ELP-intein-SacB (HEIS) protein to realize nonchromatographic purification of SacB. The efficient biomimetic mineralization of CaHPO and HEIS-based hybrid-hydrangea (CaHPO-HEIS-HH) with good reusability, excellent storage stability and 254.3% improved relative levan yield was prepared with the biomimetic mineralization method. Additionally, the CaHPO-HEIS-HH showed outstanding operation activity when catalyzing sucrose in solution and up to 75% sucrose conversion rate in fruit juices. The mechanism of biomimetic mineralization was analyzed to show that the HEIS protein might serve as a "binder" to assemble the nanoflakes during biomimetic mineralization. The CaHPO-HEIS-HH was applicable for efficient production of the levan-type prebiotic polysaccharides, and this approach should be highly valuable for nonchromatographic purification and convenient preparation of various encapsulated enzymes for more efficient catalysis.
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http://dx.doi.org/10.1016/j.carbpol.2022.119398DOI Listing
July 2022

Complex impacts of hydraulic fracturing return fluids on soil microbial community respiration, structure and functional potentials.

Environ Microbiol 2022 Apr 13. Epub 2022 Apr 13.

Department of Earth and Atmospheric Sciences, Faculty of Science, University of Alberta, Edmonton, AB, T6G 2E3, Canada.

The consequences of soils exposed to hydraulic fracturing (HF) return fluid, often collectively termed flowback and produced water (FPW), are poorly understood, even though soils are a common receptor of FPW spills. Here, we investigate the impacts on soil microbiota exposed to FPW collected from the Montney Formation of western Canada. We measured soil respiration, microbial community structure and functional potentials under FPW exposure across a range of concentrations, exposure time and soil types (luvisol and chernozem). We find that soil type governs microbial community response upon FPW exposure. Within each soil, FPW exposure led to reduced biotic soil respiration, and shifted microbial community structure and functional potentials. We detect substantially higher species richness and more unique functional genes in FPW-exposed soils than in FPW-unexposed soils, with metagenome-assembled genomes (e.g. Marinobacter persicus) from luvisol soil exposed to concentrated FPW being most similar to genomes from HF/FPW sites. Our data demonstrate the complex impacts of microbial communities following FPW exposure and highlight the site-specific effects in evaluation of spills and agricultural reuse of FPW on the normal soil functions.
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http://dx.doi.org/10.1111/1462-2920.16009DOI Listing
April 2022

Elimination of recalcitrant micropollutants by medium pressure UV-catalyzed bioelectrochemical advanced oxidation process: Influencing factors, transformation pathway and toxicity assessment.

Sci Total Environ 2022 Jul 15;828:154543. Epub 2022 Mar 15.

Department of Environmental Engineering, Technical University of Denmark, DK-2800 Lyngby, Denmark. Electronic address:

Bio-electro-Fenton (BEF) processes have been widely studied in recent years to remove recalcitrant micropollutants from wastewater. Though promising, it still faces the critical challenge of residual iron and iron sludge in the treated effluent. Thus, an innovative medium-pressure ultraviolet-catalyzed bio-electrochemical system (MUBEC), in which medium-pressure ultraviolet was employed as an alternative to iron for in-situ HO activation, was developed for the removal of recalcitrant micropollutants. The influence of operating parameters, including initial catholyte pH, cathodic aeration rate, and input voltage, on the system performance, was explored. Results indicated that complete reduction of 10 mg L of model micro-pollutants ibuprofen (IBU) and carbamazepine (CBZ) was achieved at pH 3, with an aeration rate of 1 mL min and a voltage of 0.3 V, following pseudo-first-order kinetics. Moreover, potential transformation pathways and the associated intermediates during the degradation were deduced and detected, respectively. Thus, the MUBEC system shows the potential for the efficient and cost-effective degradation of recalcitrant micropollutants from wastewater.
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http://dx.doi.org/10.1016/j.scitotenv.2022.154543DOI Listing
July 2022

Enhanced Cr(VI) reduction in biocathode microbial electrolysis cell using Fenton-derived ferric sludge.

Water Res 2022 Apr 1;212:118144. Epub 2022 Feb 1.

Department of Environmental Engineering, Technical University of Denmark, DK-2800 Lyngby, Denmark. Electronic address:

Hexavalent chromium (Cr(VI)) is one of the major concerns for water environment and human health due to its high toxicicity, while ferric sludge produced from Fenton processes is also a tough nut to crack. In this study, the synergetic impact of ferric sludge derived from the Fenton process on the bioreduction of Cr(VI) in biocathode microbial electrolysis cell was investigated for the first time. As a result, Cr(VI) reduction efficiency at biocathode increased by 1.1-2.6 times with 50 mg/L ferric sludge under different operation conditions. Besides, the Cr(VI) reduction enhancement decreased with the increase of pH and initial Cr(VI) concentration or increased with the increase of ferric sludge dosage. Correspondingly, relatively higher power density (1.027 W/m with 100 mg/L ferric sludge while 0.827 W/m for control) and lower activation energy and resistance were also observed. Besides, the presence of ferric sludge increased biomass protein (1.7 times higher with 100 mg/L ferric sludge) and cytochrome c (1.4 times higher with 100 mg/L ferric sludge). The evolution of microbial community structure for a higher abundance of Cr(VI) and Fe(III)-reducing microorganisms were exhibited, implying the enhancement of Cr(VI) reduction was due to the formation of Fe(II) from the reduction of ferric sludge. These findings provide insights and theoretical support for developing a viable biotechnology platform to realize waste treatment using waste.
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http://dx.doi.org/10.1016/j.watres.2022.118144DOI Listing
April 2022

Association of fasting blood glucose to high-density lipoprotein cholesterol ratio with short-term outcomes in patients with acute coronary syndrome.

Lipids Health Dis 2022 Jan 30;21(1):17. Epub 2022 Jan 30.

Department of Cardiovascular Medicine, The Second Xiangya Hospital, Central South University, 139 Middle Renmin Road, Changsha, 410011, Hunan, China.

Background: Biochemical markers are crucial for determining risk in coronary artery disease (CAD) patients; however, the relationship between fasting blood glucose to high-density lipoprotein cholesterol (FG/HDL-C) ratio and short-term outcomes in acute coronary syndrome (ACS) patients remains unknown. Therefore, we have investigated the relationship between the FG/HDL-C ratio and short-term outcomes in ACS patients.

Methods: We used data from a pragmatic, stepped-wedge, cluster-randomized clinical trial to perform a post hoc analysis. A total of 11,284 individuals with ACS were subdivided into quartiles according to their FG/HDL-C ratios. We used a multivariate logistic regression model, two-piecewise linear regression model, and generalized additive model (GAM) to evaluate the relationship between the FG/HDL-C ratio and short-term outcomes (major adverse cardiovascular events [MACEs] and cardiovascular [CV] death within 30 days).

Results: The FG/HDL-C ratio was remarkably linked to an enhanced risk of MACEs and CV death in individuals with ACS in the highest quartile (MACEs, odds ratio [OR]: 1.49; 95% confidence interval [CI], [1.11, 1.99]; P < 0.01; CV death, OR: 1.69; 95% CI, [1.01, 1.41]; P = 0.04). The GAM suggested that the relationship between the FG/HDL-C ratio and MACEs and CV death was non-linear. The two-piecewise linear regression model demonstrated that the threshold values were 3.02 and 3.00 for MACEs and CV death, respectively.

Conclusions: A higher FG/HDL-C ratio is associated with a higher risk of MACEs and CV death in patients with ACS.
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http://dx.doi.org/10.1186/s12944-021-01618-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8802470PMC
January 2022

Microwave-assisted iron oxide process for efficient removal of tetracycline.

J Environ Manage 2022 Apr 29;307:114600. Epub 2022 Jan 29.

Technical University of Denmark Department of Environmental Engineering, Kongens Lyngby, Denmark.

Excess tetracycline produced by livestock and poultry breeding industry not only pollute the environment, but also enter the human body with the spread of the food chain, which will produce drug-resistant genes and threaten human health. In this paper, the adsoption of tetracycline from wastewater using iron oxide under microwave oxidation condition was explored. The effect of initial pollutant concentrations, the dosage of iron oxide, pH value, and temperature on the hybrid treatment process was investigated. Under the normal iron oxide and microwave oxidation conditions, when the dosage of iron oxide was 40 g/L and 30 g/L, pH was 10 and the temperature was 318 K, the removal rate of tetracycline was significantly improved. The adsorption of tetracycline by iron oxide under the two conditions conformed to the Freundlich isotherm model and pseudo-second-order dynamics model. In addition, the associated adsorption mechanism was unveiled. Under the microwave oxidation condition, the hot spot effect generated by the microwave oxidation effect would rapidly increase its surface temperature to form the active center and the electrostatic gravity to promote the reaction. The results indicated that microwave oxidation could promote the removal of antibiotics by iron oxide in livestock and poultry breeding wastewater.
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http://dx.doi.org/10.1016/j.jenvman.2022.114600DOI Listing
April 2022

Vagus Nerve Stimulation Attenuates Acute Skeletal Muscle Injury Induced by Hepatic Ischemia/Reperfusion Injury in Rats.

Front Pharmacol 2021 3;12:756997. Epub 2022 Jan 3.

Department of Cardiovascular Medicine, The Second Xiangya Hospital, Central South University, Changsha, China.

Vagus nerve stimulation (VNS) has a protective effect on distal organ injury after ischemia/reperfusion (I/R) injury. We aimed to investigate the protective efficacy of VNS on hepatic I/R injury-induced acute skeletal muscle injury and explore its underlying mechanisms. To test this hypothesis, male Sprague-Dawley rats were randomly divided into three groups: sham group (sham operation, n = 6); I/R group (hepatic I/R with sham VNS, n = 6); and VNS group (hepatic I/R with VNS, n = 6). A hepatic I/R injury model was prepared by inducing hepatic ischemia for 1 h (70%) followed by hepatic reperfusion for 6 h. VNS was performed during the entire hepatic I/R process. Tissue and blood samples were collected at the end of the experiment for biochemical assays, molecular biological preparations, and histological examination. Our results showed that throughout the hepatic I/R process, VNS significantly reduced inflammation, oxidative stress, and apoptosis, while significantly increasing the protein levels of silent information regulator 1 (SIRT1) and decreasing the levels of acetylated forkhead box O1 and Ac-p53, in the skeletal muscle. These data suggest that VNS can alleviate hepatic I/R injury-induced acute skeletal muscle injury by suppressing inflammation, oxidative stress, and apoptosis, potentially via the SIRT1 pathway.
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http://dx.doi.org/10.3389/fphar.2021.756997DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8762262PMC
January 2022

Electrochemical and microbiological response of exoelectrogenic biofilm to polyethylene microplastics in water.

Water Res 2022 Mar 7;211:118046. Epub 2022 Jan 7.

Department of Environmental Engineering, Technical University of Denmark, Lyngby DK-2800, Denmark. Electronic address:

Exoelectrogenic biofilm and the associated microbial electrochemical processes have recently been intensively studied for water treatment, but their response to and interaction with polyethylene (PE) microplastics which are widespread in various aquatic environments has never been reported. Here, we investigated how and to what extent PE microplastics would affect the electrochemistry and microbiology of exoelectrogenic biofilm in both microbial fuel cells (MFCs) and microbial electrolysis cells (MECs). When the PE microplastics concentration was increased from 0 to 75 mg/L in the MECs, an apparent decline in the maximum current density (from 1.99 to 0.74 A/m) and abundance of electroactive bacteria (EAB) in the exoelectrogenic biofilm was noticed. While in the MFCs, the current output was not significantly influenced and the abundance of EAB lightly increased at 25 mg/L microplastics. In addition, PE microplastics restrained the viability of the exoelectrogenic biofilms in both systems, leading to a higher system electrode resistance. Moreover, the microbial community richness and the microplastics-related operational taxonomic units decreased with PE microplastics. Furthermore, the electron transfer-related genes (e.g., pilA and mtrC) and cytochrome c concentration decreased after adding microplastics. This study provides the first glimpse into the influence of PE microplastics on the exoelectrogenic biofilm with the potential mechanisms revealed at the gene level, laying a methodological foundation for the future development of efficient water treatment technologies.
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http://dx.doi.org/10.1016/j.watres.2022.118046DOI Listing
March 2022

The role of posterior pallial amygdala in mediating motor behaviors in pigeons.

Sci Rep 2022 01 10;12(1):367. Epub 2022 Jan 10.

School of Life Sciences, Zhengzhou University, No. 100 Science Avenue, Zhengzhou, 450001, Henan Province, People's Republic of China.

The posterior pallial amygdala (PoA) is located on the basolateral caudal telencephalon, including the basal division of PoA (PoAb) and the compact division of PoA (PoAc). PoA plays a vital role in emotion regulation and is considered a part of the amygdala in birds. However, the regulatory functions responsible for motor behaviors and emotions between PoAb and PoAc are poorly understood. Therefore, we studied the structure and function of PoA by tract-tracing methods, constant current electrical stimulation, and different dopamine receptor drug injections in pigeons (Columba livia domestica). PoAb connects reciprocally with two nuclear groups in the cerebrum: 1) a continuum comprising the temporo-parieto-occipitalis, corticoidea dorsolateralis, hippocampus, and parahippocampalis areas and 2) rostral areas of the hemisphere, including the nucleus septalis lateralis and nucleus taeniae amygdalae. Extratelencephalic projections of PoAb terminate in the lateral hypothalamic nucleus and are scattered in many limbic midbrain regions. PoAb and PoAc mainly mediated the turning movement. In the 'open-field' test, D1 agonist and D2 antagonist could significantly reduce the latency period for entering into the central area and increase the residence time in the central area, whereas D1 antagonist and D2 agonist had the opposite effect. PoAb and PoAc are important brain areas that mediate turning behavior.
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http://dx.doi.org/10.1038/s41598-021-03876-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8748633PMC
January 2022

Correction: ZDY01 inhibits choline-induced atherosclerosis through CDCA-FXR-FGF15 axis.

Food Funct 2022 Jan 4;13(1):459. Epub 2022 Jan 4.

Department of Physiology and Centre for Metabolic Disease Research, Lewis Katz School of Medicine, Temple University, Philadelphia, PA 19140, USA.

Correction for ' ZDY01 inhibits choline-induced atherosclerosis through CDCA-FXR-FGF15 axis' by Jinghui Tang , , 2021, , 9932-9946, DOI: 10.1039/D1FO02021H.
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http://dx.doi.org/10.1039/d1fo90118dDOI Listing
January 2022

Cytochrome P450s in plant terpenoid biosynthesis: discovery, characterization and metabolic engineering.

Crit Rev Biotechnol 2021 Dec 5:1-21. Epub 2021 Dec 5.

Beijing Shijitan Hospital, Capital Medical University, Beijing, China.

As the largest family of natural products, terpenoids play valuable roles in medicine, agriculture, cosmetics and food. However, the traditional methods that rely on direct extraction from the original plants not only produce low yields, but also result in waste of resources, and are not applicable at all to endangered species. Modern heterologous biosynthesis is considered a promising, efficient, and sustainable production method, but it relies on the premise of a complete analysis of the biosynthetic pathway of terpenoids, especially the functionalization processes involving downstream cytochrome P450s. In this review, we systematically introduce the biotech approaches used to discover and characterize plant terpenoid-related P450s in recent years. In addition, we propose corresponding metabolic engineering approaches to increase the effective expression of P450 and improve the yield of terpenoids, and also elaborate on metabolic engineering strategies and examples of heterologous biosynthesis of terpenoids in and plant hosts. Finally, we provide perspectives for the biotech approaches to be developed for future research on terpenoid-related P450.
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http://dx.doi.org/10.1080/07388551.2021.2003292DOI Listing
December 2021

Activation of persulfate for highly efficient degradation of metronidazole using Fe(II)-rich potassium doped magnetic biochar.

Sci Total Environ 2022 May 29;819:152089. Epub 2021 Nov 29.

Department of Environmental Engineering, Technical University of Denmark, DK-2800 Lyngby, Denmark.

The content of active components in magnetic biochar, especially Fe(II), is closely related to its activation performance. Therefore, improving Fe(II) content in magnetic biochar is an ideal strategy to enhance the activation performance of magnetic biochar. In this study, the potassium-doped magnetic biochar was prepared and employed to activate persulfate for degradation of metronidazole. The degradation efficiency of metronidazole in potassium-doped magnetic biochar/persulfate system was 98.4%, which was 13.1 times higher than that in magnetic biochar/persulfate system. Free radicals quenching experiments and electron spin resonance analyses confirmed that surface-bound free radicals were responsible for metronidazole degradation followed the order of O > ·OH > SO· > O·. The doping of magnetic biochar with potassium increased its Fe(II) content, approximately 3.1 times higher than that of pristine magnetic biochar. The differences in Fe(II) content between potassium-doped magnetic biochar and magnetic biochar were the key reasons for the activation performance differences. Based on the ultra-high pressure liquid chromatography-quadrupole tandem time-of-flight mass spectrometer, the primary degradation intermediates of metronidazole were identified, and possible degrading pathways were proposed. Overall, this work provides an effective strategy to improve the activation performance of magnetic biochar.
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http://dx.doi.org/10.1016/j.scitotenv.2021.152089DOI Listing
May 2022
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