期刊：
Critical Reviews in Environmental Science and Technology,2024年:09 ISSN：1064-3389
通讯作者：
Zhou, YY
作者机构：
[Yao, Bin; Zhou, YY; Zhou, Yaoyu] Hunan Agr Univ, Coll Environm & Ecol, Hunan Int Sci & Technol Cooperat Base Agr Typ Poll, Changsha 410128, Hunan, Peoples R China.
通讯机构：
[Zhou, YY ] H;Hunan Agr Univ, Coll Environm & Ecol, Hunan Int Sci & Technol Cooperat Base Agr Typ Poll, Changsha 410128, Hunan, Peoples R China.
关键词：
Neonicotinoid insecticides;remediation;wastewater treatment;advanced oxidation processes;adsorption;bioremediation;Eakalak Khan and Scott Bradford
摘要：
The extensive application of neonicotinoid insecticides (NNIs) has resulted in its worldwide detection in waters, leading to risks to human health and ecology safety. Presently, various remediation techniques for NNIs have been developed. However, the critical reviews concerning the remediation approaches for the elimination of NNIs from water are limited. Considering tremendous efforts have been made in the research topic of NNIs removal recently, this study systematacially reviewed the current advances on NNIs remediation approaches, including adsorption, Fenton, ozonation, photodegradation, sulfate radicals based-advanced oxidation processes (AOPs), electrochemical AOPs, percarbonate-based AOPs, periodate-based AOPs, microbial remediation, and phytoremediation. Moreover, NNIs removal by these methods have been critically discussed, compared, and analyzed. Furthermore, mechanisms of different treatment processes have been summarized in detail. Finally, the challenges and perspectives have been proposed. This study highlights the current progresses on NNIs removal technologies and proposes the future research needs in this area, which will provide support to further researches to halt the NNIs contamination.
摘要：
Background: Tea is a globally significant agricultural product, renowned for its economic and cultural value. The process of tea cultivation and production involves tea plantation management, disease control, harvesting, processing, sorting and safety and quality assessment. The quality of tea can be affected by many factors, involving variety, environment, picking and processing. Nevertheless, quality assessment of tea often relies on manual experience and specialized knowledge, which is accompanied by subjectivity and inconsistency. Furthermore, the tea production process also faces several challenges, such as pest and disease prediction and detection, supply chain monitoring and traceability. Scope and approach: This review introduces intelligent technologies applied in tea industry, including computer vision, machine learning, spectroscopic techniques, artificial sensors, big data, internet of things, and blockchain. We summarize the progress of the application of intelligent technologies in tea industry, analyze the existing challenges and gaps, and suggest future research trends. The review is expected to provide novel insights into the application of intelligent technologies in tea industry to build a transparent, traceable, and sustainable tea industry chain. Key findings and conclusions: Intelligent technologies have a broad application prospect in tea industry to improve product quality, efficiency, transparency, and traceability. Particularly, combination of intelligent technologies may result in better performance. Open datasets are necessary for storage of huge amount of information. Standardization of intelligent technologies establishes a solid foundation for development of sustainable tea industry. Furthermore, transition to portable devices is the most responsive direction to tea market demands.
摘要：
The generation of hydroxyl radicals (center dot OH) mediated by Fe(II) has drawn increasing amounts of attention due to its significant role in the transformation of soil organic carbon (SOM) during redox fluctuations in paddy soil. This study further examined the effect of long-term (since 1984) straw return on Fe(II) on driving center dot OH formation and SOM transformation upon paddy soils oxygenation. We found that long-term straw return could inhibit the center dot OH and CO2 production in abiotic processes. The center dot OH production decreased from 190.4 to 133.4 mu M as the straw return amount increased from 0 to 19.16 t center dot hm 2 center dot year 1. Moreover, 14.7-38.6 % of the CO2 production was associated with center dot OH during oxygenation. By combining radical quenching and OM extraction, we determined that straw return could increase O2 reduction to H2O2 through a two-electron transfer pathway. Based on chemical extraction, Mo center dot ssbauer spectra and multilinear regression model, we demonstrated that straw return resulted in more active Fe(II) species that controls the center dot OH production. The results of 3DEEMs and FT-ICR MS showed that oxidative transformation can be accomplished by the introduction of center dot OH to aromatic structures or olefins through ring opening and hydroxylation mechanisms. And OM at high straw return concentrations was likely oxidized by center dot OH into bioavailable aliphatic compounds. Therefore, this study highlights the underappreciating effects of long-term straw return on Fe(II) oxidation in driving center dot OH generation and SOM transformation in paddy soil redox fluctuation events.
通讯机构：
[Tang, JF; Deng, L ] H;Hunan Agr Univ, Sch Chem & Mat Sci, Changsha, Hunan 410128, Peoples R China.
关键词：
Small -angle X-ray scattering;Nanoparticles
摘要：
Small-angle X-ray scattering (SAXS) is an operando structure characterization tool that is unique in its ability to detect diverse nano-particulate materials. Guinier approximation and form factor can efficiently extract statistically meaningful structure information such as size and morphology from SAXS data. Herein, by employing a simulation of scattering intensities via a lattice-atoms-based code, we demonstrate quantitative correlation be-tween SAXS data and the structural characteristics in real space for single Pt nanoparticle with different size and structure motifs. It is shown that, for particles with varied morphologies, the symmetry of 2D patterns strongly depend on the orientation of facets. However, the oscillation in frequencies and amplitudes of 1D profile, the azimuthally averaged and integrated 2D patterns, are not so sensitive to structure motifs. Regardless of particle shapes, the discrepancy between the actual particle sizes and evaluated values from 1D profile, obtained by utilizing the form factors or Guinier approximation, are pretty small. Such discrepancy is more apparent for smaller particles, attributed to strong size-dependence of surface constitution, especially for spheres. By conducting a detailed analysis of the correlation between real-space and reciprocal-space lattice information, this work highlights the continuous-to-discrete transition of nano-objects and paves the way to accurately deter-mining structural features from SAXS data.
摘要：
Hybrid rice (Oryza sativa) generally outperforms its inbred parents in yield and stress tolerance, a phenomenon termed heterosis, but the underlying mechanism is not completely understood. Here, we combined transcriptome, proteome, physiological, and heterosis analyses to examine the salt response of super hybrid rice Chaoyou1000 (CY1000). In addition to surpassing the mean values for its two parents (mid-parent heterosis), CY1000 exhibited a higher reactive oxygen species scavenging ability than both its parents (over-parent heterosis or heterobeltiosis). Nonadditive expression and allele-specific gene expression assays showed that the glutathione S-transferase gene OsGSTU26 and the amino acid transporter gene OsAAT30 may have major roles in heterosis for salt tolerance, acting in an overdominant fashion in CY1000. Furthermore, we identified OsWRKY72 as a common transcription factor that binds and regulates OsGSTU26 and OsAAT30. The salt-sensitive phenotypes were associated with the OsWRKY72(paternal) genotype or the OsAAT30(maternal) genotype in core rice germplasm varieties. OsWRKY72(paternal) specifically repressed the expression of OsGSTU26 under salt stress, leading to salinity sensitivity, while OsWRKY72(maternal) specifically repressed OsAAT30, resulting in salinity tolerance. These results suggest that the OsWRKY72-OsAAT30/OsGSTU26 module may play an important role in heterosis for salt tolerance in an overdominant fashion in CY1000 hybrid rice, providing valuable clues to elucidate the mechanism of heterosis for salinity tolerance in hybrid rice.
关键词：
Sulfur -doped BiOCl;Molecular oxygen activation;Built-in electric field;Exciton dissociation;CIP degradation
摘要：
The reactive oxygen species (ROS) generated by photoinduced molecular oxygen (O2) activation has attracted great attention in environmental remediation and pollution control. Herein, we establish a facile sulfur doping strategy that promotes the activation of molecular oxygen over BiOCl for rapid and continuous degradation of organic pollutants. In this work, we demonstrate that the significantly enhanced built-in electric field (BIEF) induced by the heterogeneous introduction of S atoms not only multiplies the electron concentration in the BiOCl matrix, but also accelerates the rapid separation/transfer of charge carriers and inhibits recombination. Driven by this, the exciton behavior in the BOC undergoes a transformation. The electrons generated through exciton dissociation activate the adsorbed O2 on the surface into superoxide radicals (center dot O2-). Benefited from the superior O2 activation efficiency, the degradation rate constant of ciprofloxacin (CIP) the fabricated S-doped BiOCl increased by 8.8 times, under visible light. This work proposes a strategy to promote the photocatalytic O2 activation via tuning BIEF and manipulating excitonic effects, which affords new perspective for understanding the reaction mechanisms related to charge transfer in photocatalytic systems.
摘要：
Root rot is an important disease of tea plants owing to its unobvious early symptoms and permanent damage (Huu et al. 2016). In 2019, 5% of tea plants displayed symptoms consistent with root rot in a tea plantation (28°09'N, 113°13'E) located in Changsha city, Hunan province of China. The symptoms of the diseased tea plants ranged from wilting leaves to entirely dead. The roots had black lesions and rot typical of this disease. Symptomatic roots were collected, washed with water and disinfected with 75% ethanol, then cut into pieces and sterilized with 0.1% mercuric chloride for 30 s, 75% ethanol for 1 min, and rinsed with sterile water five times. After drying on sterilized filter paper, root tissues were cultured on potato dextrose agar (PDA) medium at 25 oC for 7 days in the dark. Four isolates, CAGF1, CAGF2, CAGF3, and CAGF4 were purified by selecting single spores. All isolates were subjected to a pathogenicity test. A conidial suspension of each strain was collected at a concentration of 2×106 conidia/mL. For the pathogenicity test, two-year-old field grown tea plants were transplanted in plastic pots containing 240 g of the rice grain-bran mixture (inoculated with 4 mL of conidial suspension and cultured for 14 days) and 960 g of sterilized soil (Huu et al. 2016). The pots without inoculated mixture served as control group. All the pots were kept in illumination incubators at 25 (o)C and a 12L:12D photoperiod. The pathogenicity test for each strain was repeated three times with three repetitions. Only strain CAGF1 exhibited pathogenicity to tea plants. Symptoms appeared on the third day post inoculation (dpi) and gradually worsened by the 7 dpi. On the 14 dpi, most leaves had died and the roots were black and partially rotten, similar to field symptoms. The reisolated fungus from potted roots was identified as CAGF1 based on ITS region and colony morphology, while isolation was attempted, CAGF1 was not isolated from the control plants, which fulfilled Koch's postulates. On PDA, the colony center of CAGF1 was purple with white margin, while on carnation leaf agar (CLA) medium was white. On CLA medium, macroconidia have 0 to 3 septa, measured 19.1 μm to 41.2 μm × 4.2 μm to 5.4 μm (mean= 31.2 μm × 4.8 μm, n=30). The microconidia were measured as 6.7 μm to 12.8 μm × 2.4 μm to 4.9 μm (mean= 10.1 μm × 3.3 μm, n=30), with 0 to 1 septa. And the chlamydospores were measured as 6.0 to 9.7μm (mean= 7.7μm, n=30). Morphologically, strain CAGF1 was identified as Fusarium oxysporum (Leslie and Summerell 2006). Additionally, the genomic DNA of strain CAGF1 was extracted by cetyltrimethylammonium bromide (CTAB) method, the internal transcribed spacer (ITS), elongation factor 1 alpha (EF-1α) and second largest subunit of RNA polymerase II (RPB2) were amplified using the primers ITS1/ITS4 (White et al. 1990), EF-1/EF-2 (Geiser et al. 2004) and fRPB2-5F/fRPB2-7cR (Liu et al. 1999), respectively. Sequences were deposited in GenBank (ITS, OK178562.1; EF-1α, OK598121.1; RPB2, OP381476.1). BLASTn searches revealed that strain CAGF1 was 100% (ON075522.1 for ITS and JX885464.1 for RPB2) and 99.6% (JQ965440.1 for EF-1α) identical to Fusarium oxysporum species complex (FOSC). Based on phylogenetic analysis, the strain CAGF1 was identified as Fusarium cugenangense, belonging to FOSC. To our knowledge, this is the first report of F. cugenangense causing root rot of tea plants in China. The findings are important for the management of this root rot and the improvement of economic benefits of tea cultivation.
通讯机构：
[Yang, Y ; Wu, HZ ] H;Hunan Prov Inst Prod & Goods Qual Inspect, Changsha 410007, Peoples R China.;Hunan Agr Univ, Coll Resources & Environm, Changsha 410128, Hunan, Peoples R China.
摘要：
The emerging sample pretreatment technique of magnetic solid-phase extraction (MSPE) has drawn the attention of researchers owing to its advantages of less reagent consumption, fast separation/enrichment process, high adsorption capacity, and simple operation. This paper presents a review of synthesis techniques, classification, and analysis procedures for MSPE in the detection of heavy metals in food. Magnetic adsorbents derived from silica, metal oxides, carbon, polymers, etc., are applied for the detection of heavy metals in food. Then, the recent development of the technology of MSPE for the analysis of heavy metal extraction in food is summarized in detail. Finally, the future outlook for the improvement of MSPE is also discussed. The emerging sample pretreatment technique of magnetic solid-phase extraction (MSPE).
摘要：
Fumonisins (FBs), particularly fumonisin B1 (FB1) and fumonisin B2 (FB2) produced mainly by Fusarium verticillioide and Fusarium proliferatum, are common contaminants in animal feed and pose a serious threat to both animal and human health. The use of microbial enzymes to efficiently and specifically convert fumonisins into non-toxic or low-toxic metabolites has emerged as the most promising approach. However, most of the available enzymes have only been evaluated in vitro and lack systematic evaluation in vivo. In this study, the detoxification efficacy of two carboxylesterases, FumD (FUMzyme (R)) and FumDSB, was evaluated comparatively in piglets. The results show that feeding piglets 4.4 mg/kg FBs-contaminated diets for 32 days did not significantly affect the average daily gain, organ indices, and immunoglobulins of the piglets. However, a significant reduction (21.2%) in anti-inflammatory cytokine interleukin-4 was observed in the FBs group, and supplementation with FUMzyme (R) and FumDSB significantly increased interleukin-4 by 62.1% and 28.0%, respectively. In addition, FBs-contaminated diets resulted in a 3-fold increase in the serum sphinganine/sphingosine (Sa/So) ratio, which is a specific biomarker that has been used to accurately reflect fumonisin levels. The serum Sa/So ratio was significantly reduced by 48.8% after the addition of FUMzyme (R), and was insignificantly reduced by 8.2% in the FumDSB group. These results suggested that FUMzyme was more effective than FumDSB in mitigating FBs toxicity in piglets by down-regulating the Sa/So ratio.
摘要：
Phyllosphere microorganisms have recently attracted the attention of scientists studying plant microbiomes. The origin, diversity, functions, and interactions of phyllosphere microorganisms have been extensively explored. Many experiments have demonstrated seasonal cycles of phyllosphere microbes. However, a comprehensive comparison of these separate investigations to characterize seasonal trends in phyllosphere microbes of woody and herbaceous plants has not been conducted. In this review, we explored the dynamic changes of phyllosphere microorganisms in woody and non-woody plants with the passage of the season, sought to find the driving factors, summarized these texts, and thought about future research trends regarding the application of phyllosphere microorganisms in agricultural production. Seasonal trends in phyllosphere microorganisms of herbaceous and woody plants have similarities and differences, but extensive experimental validation is needed. Climate, insects, hosts, microbial interactions, and anthropogenic activities are the diverse factors that influence seasonal variation in phyllosphere microorganisms.
关键词：
functional-structure plant modeling (FSPM);mechanized planting;micro-light climate;Chinese solar greenhouse;GroIMP
摘要：
Understanding the spatial heterogeneity of light and photosynthesis distribution within a canopy is crucial for optimizing plant growth and yield, especially in the context of greenhouse structures. In previous studies, we developed a 3D functional-structural plant model (FSPM) of the Chinese solar greenhouse (CSG) and tomato plants, in which the greenhouse was reconstructed as a 3D mockup and implemented in the virtual scene. This model, which accounts for various environmental factors, allows for precise calculations of radiation, temperature, and photosynthesis at the organ level. This study focuses on elucidating optimal canopy configurations for mechanized planting in greenhouses, building upon the commonly used north-south (N-S) orientation by exploring the east-west (E-W) orientation. Investigating sixteen scenarios with varying furrow distance (1 m, 1.2 m, 1.4 m, 1.6 m) and row spacing (0.3 m, 0.4 m, 0.5 m, 0.6 m), corresponding to 16 treatments of plant spacing, four planting patterns (homogeneous row, double row, staggered row, incremental row) and two orientations were investigated. The results show that in Shenyang city, an E-W orientation with the path width = 0.5 (furrow distance + row distance) = 0.8 m (homogeneous row), and a plant distance of 0.32 m, is the optimal solution for mechanized planting at a density of 39,000 plants/ha. Our findings reveal a nuanced understanding of how altering planting configurations impacts the light environment and photosynthesis rate within solar greenhouses. Looking forward, these insights not only contribute to the field of CSG mechanized planting, but also provide a basis for enhanced CSG planting management. Future research could further explore the broader implications of these optimized configurations in diverse geographic and climatic conditions.
摘要：
Tocopherol is an important lipid-soluble antioxidant beneficial for both human health and plant growth. Here, we fine mapped a major QTL-qVE1 affecting γ-tocopherol content in maize kernel, positionally cloned and confirmed the underlying gene ZmPORB1 (por1), as a protochlorophyllide oxidoreductase. A 13.7 kb insertion reduced the tocopherol and chlorophyll content, and the photosynthetic activity by repressing ZmPORB1 expression in embryos of NIL-K22, but did not affect the levels of the tocopherol precursors HGA (homogentisic acid) and PMP (phytyl monophosphate). Furthermore, ZmPORB1 is inducible by low oxygen and light, thereby involved in the hypoxia response in developing embryos. Concurrent with natural hypoxia in embryos, the redox state has been changed with NO increasing and H(2)O(2) decreasing, which lowered γ-tocopherol content via scavenging reactive nitrogen species. In conclusion, we proposed that the lower light-harvesting chlorophyll content weakened embryo photosynthesis, leading to fewer oxygen supplies and consequently diverse hypoxic responses including an elevated γ-tocopherol consumption. Our findings shed light on the mechanism for fine-tuning endogenous oxygen concentration in the maize embryo through a novel feedback pathway involving the light and low oxygen regulation of ZmPORB1 expression and chlorophyll content.
关键词：
Land green use efficiency;digital transformation;Resource-based cities;"Broadband China" policy;Stochastic frontier analysis
摘要：
Introduction: Improving land use efficiency is a necessary way to promote sustainable urban development. The objective of this study is to examine the issue of land green use efficiency (LGUE) in resource-based cities and analyze the impact of digital transformation on LGUE. The research utilizes data from 113 resource-based cities in China spanning from 2008 to 2020.Methodology: Firstly, using the stochastic frontier analysis (SFA) to measure LGUE in China cities, this paper investigates the spatial and temporal evolution of LGUE in different cities. Then, this paper explores the impact of digital transformation on the LGUE of resource-based cities based on the broadband China policy using the DID method.Findings: According to the data measured by the SFA, it is found that resource-based cities are 20.4% lower than non-resource-based cities. An in-depth study found that digital transformation significantly improves LGUE, and the effect is greater in resource-based cities, which is a powerful tool to solve the difficulty of LGUE in resource-based cities. Specifically, digital transformation helps to improve the LGUE of resource-based cities enhance by technological innovation and industrial structure upgrading, and alleviating land factor mismatch.Discussion: It is not only necessary to guide and encourage the in-depth integration of traditional industries with digital technology to enhance the digital transformation of resource-based cities, but also to continuously optimize the allocation of land resources between regions and narrow the gap in LGUE between cities.
摘要：
P2-type layered oxide, Na2/3Ni1/3Mn2/3O2, has drawn particular interest as a promising cathode material for sodium-ion batteries (SIBs) due to its fast sodium-ion transport channels with low migration potential. However, some catastrophic flaws, such as air instability, complicated multiphase evolution, and irreversible anionic redox, limit its electrochemical performance and hinder its application. Here, an air-stable single-crystal P2-type Na2/3Ni1/3Mn1/3Ti1/3O2 is proposed based on the multifunctional structural modulation of Ti substitution that could alleviate the issues for practical SIBs. As a result, the cathode with high energy density shows excellent air stability and highly reversible phase transitions (P2-OP4), and delivers faster kinetics and stable anion redox chemistry. Meanwhile, a thorough investigation of the relationship between structure, function, and properties is demonstrated, emphasizing formation processes, electrochemical behavior, structural evolution, and air stability. Overall, this study provides the direction of multifunctional structural modulation for the development of high-performance sodium-based layered cathode materials for practical applications.
期刊：
Current Microbiology,2024年81(1):1-8 ISSN：0343-8651
通讯作者：
Pan, H;Pan, Hu;Tian, Y
作者机构：
[Dai, Yan-na; Pan, H; Zhang, Yi-fan; Pan, Hu; Pu, Ji-feng] Tibet Acad Agr & Anim Husb Sci, Inst Agr Qual Stand & Testing, Lhasa 850032, Peoples R China.;[Tian, Yun; Liu, Hu-hu; Tian, Y; Pan, Hu; Pan, H] Hunan Agr Univ, Coll Biosci & Biotechnol, Changsha 410128, Peoples R China.;[Dai, Yan-na; Pan, H; Zhang, Yi-fan; Pan, Hu; Pu, Ji-feng] Agr & Livestock Prod Engn Technol Res Ctr Tibet Au, Lhasa 850032, Peoples R China.;[Yang, Xiao-feng] Sichuan Acad Agr Sci, Inst Agr Qual Stand & Testing Technol, Chengdu 610066, Peoples R China.
通讯机构：
[Pan, H ] T;[Tian, Y ; Pan, H] H;Tibet Acad Agr & Anim Husb Sci, Inst Agr Qual Stand & Testing, Lhasa 850032, Peoples R China.;Hunan Agr Univ, Coll Biosci & Biotechnol, Changsha 410128, Peoples R China.;Agr & Livestock Prod Engn Technol Res Ctr Tibet Au, Lhasa 850032, Peoples R China.
摘要：
A novel Gram-stain-negative, aerobic, rod-shaped bacterium named T808(T) was isolated from an alpine soil in Qamdo, Tibet, PR China. Strain T808(T) grew at 5-30degree celsius, pH 5.0-9.0 (optimum, 25degree celsius and pH 7.0-8.0) with 0-2% (w/v) NaCl (optimum, 0%). The 16S rRNA gene sequences of strain T808(T) showed the highest similarity with Pararhizobium herbae CCBAU83011(T) (98.8%), followed by Pararhizobium polonicum F5.1(T) (98.7%), Pararhizobium giardinii H152(T) (98.5%), Rhizobium gei ZFJT-2( T) (98.4%), and Pararhizobium antarcticum NAQVI59(T) (97.5%). The highest digital DNA-DNA hybridization (dDDH), core-proteome average amino acid identity (cpAAI) and average nucleotide identity (ANI) values between strain T808(T) and related strains were estimated as 28.0%, 92.1% and 84.4%, respectively. Phylogenetic analysis based on 16S rRNA, core-proteome and whole-genome indicated that strain T808(T) belonged to the genus Pararhizobium. The genome size was 6.24 Mbp with genomic DNA G + C content of 60.1%. The major cellular fatty acids were Summed feature 8 (C-18:1 omega 7c or C-18:1 omega 6c), C-16:0 and C-19:0 cyclo omega 8c. The polar lipids were diphosphatidyl glycerol, phosphatidyl glycerol, phosphatidyl ethanolamine, phosphatidyl choline and unidentified aminophospholipid. The isoprenoid quinone were ubiquinone-10 and ubiquinone-9. Based on phenotypic, phylogenetic, and genotypic data, strain T808(T) is considered to represent a novel species of the genus Pararhizobium, for which the name Pararhizobium qamdonense sp. nov. is proposed. The type strain is T808(T) (= JCM 36247( T) = CICC 25216( T)). According to phylogenetic coherence based on 16S rRNA, core-proteome and whole-genome, it is also proposed that the type strain Rhizobium gei Shi et al. 2016 should be reclassified as Pararhizobium gei comb. nov., the type strain is ZFJT-2( T) (= CCTCC AB 2013015( T) = KCTC 32301( T) = LMG 27603( T)).
摘要：
The study aimed to explore the role of glucagon in regulating glucose metabolism and gain insight into the reasons for glucose intolerance in carnivorous fish. Firstly, Japanese flounder was injected intraperitoneally with glucagon and small interfering RNA (siRNA) targeted glucagon receptor a (GCGRa), cAMP-response element binding protein 1 (CREB1), and peroxisome proliferator-activated receptor-gamma-coactivator 1 alpha (PGC-1 alpha). Secondly, a two-week feeding trial was conducted with Japanese flounder fed diets with 11.95% and 31.96% dietary carbohydrates, respectively. At the start and 7th day of the feeding trial, flounders fed each diet were intraperitoneally injected with saline or siGCGRa. Furthermore, the fish were separated into two groups and fasted for 72 h. Saline and siGCGRa were injected respectively at 6 h after feeding. The results showed that glucagon activated gluconeogenesis in the liver, leading to an elevation of plasma glucose levels, while interference of GCGRa, CREB1, and PGC-1 alpha caused the opposite results. Elevated dietary carbohydrate intake increased plasma glucose and insulin levels. Meanwhile, the glucagon signaling pathway was activated. After interference with the GCGRa, plasma glucose decreased, and the glucagon pathway was inhibited. The plasma insulin increased, and the mRNA expression of protein kinase B 8 (akt2) was up-regulated accordingly. In addition, upon injecting siGCGRa, it was observed that gluconeogenesis in the liver and plasma glucose levels during fasting were reduced in comparison to the control group. In contrast, plasma insulin levels and the transcription levels of akt2 and glucokinase (gck) in the liver exhibited an increase. In summary, the uninhibited glucagon signaling pathway promoted gluconeogenesis and suppressed the action of insulin in Japanese flounder, which might be the reason for the glucose intolerance.
关键词：
gut microbiome;pig;core gut microbes;gene catalog;germ-free mice
摘要：
Domestic pigs (Sus scrofa) are the leading terrestrial animals used for meat production. The gut microbiota significantly affect host nutrition, metabolism, and immunity. Hence, characterization of the gut microbial structure and function will improve our understanding of gut microbial resources and the mechanisms underlying host-microbe interactions. Here, we investigated the gut microbiomes of seven pig breeds using metagenomics and 16S rRNA gene amplicon sequencing. We established an expanded gut microbial reference catalog comprising 17 020 160 genes and identified 4910 metagenome-assembled genomes. We also analyzed the gut resistome to provide an overview of the profiles of the antimicrobial resistance genes in pigs. By analyzing the relative abundances of microbes, we identified three core-predominant gut microbes (Phascolarctobacterium succinatutens, Prevotella copri, and Oscillibacter valericigenes) in pigs used in this study. Oral administration of the three core-predominant gut microbes significantly increased the organ indexes (including the heart, spleen, and thymus), but decreased the gastrointestinal lengths in germ-free mice. The three core microbes significantly enhanced intestinal epithelial barrier function and altered the intestinal mucosal morphology, as was evident from the increase in crypt depths in the duodenum and ileum. Furthermore, the three core microbes significantly affected several metabolic pathways (such as "steroid hormone biosynthesis," "primary bile acid biosynthesis," "phenylalanine, tyrosine and tryptophan biosynthesis," and "phenylalanine metabolism") in germ-free mice. These findings provide a panoramic view of the pig gut microbiome and insights into the functional contributions of the core-predominant gut microbes to the host.
摘要：
Trichoderma harzianum exhibits a strong biological control effect on many important plant pathogens, such as Fusarium oxysporum, Botrytis cinerea, and Meloidogyne. However, its biocontrol effectiveness is weakened or reduced under salt stress. The aim of this study was to investigate the molecular response of T. harzianum to salt stress at the whole-genome level. Here, we present a 44.47 Mb near-complete genome assembly of the T. harzianum qt40003 strain for the first time, which was assembled de novo with 7.59 Gb Nanopore sequencing long reads (~170-fold) and 5.2 Gb Illumina short reads (~116-fold). The assembled qt40003 genome contains 12 contigs, with a contig N50 of 4.81 Mb, in which four of the 12 contigs were entirely reconstructed in a single chromosome from telomere to telomere. The qt40003 genome contains 4.27 Mb of repeat sequences and 12,238 protein-coding genes with a BUSCO completeness of 97.5%, indicating the high accuracy and completeness of our gene annotations. Genome-wide transcriptomic analysis was used to investigate gene expression changes related to salt stress in qt40003 at 0, 2% (T2), and 4% (T4) sodium chloride concentrations. A total of 2,937 and 3,527 differentially expressed genes (DEGs) were obtained under T2 and T4 conditions, respectively. GO enrichment analysis showed that the T2-treatment DEGs were highly enriched in detoxification (p < 0.001), while the T4 DEGs were mainly enriched in cell components, mostly in cellular detoxification, cell surface, and cell wall. KEGG metabolic pathway analysis showed that 91 and 173 DEGs were significantly enriched in the T2 and T4 treatments, respectively (p < 0.01), mainly in the glutathione metabolism pathway. We further experimentally analyzed the differentially expressed glutathione transferase genes in the glutathione metabolic pathway, most of which were downregulated (13/15). In addition, we screened 13 genes related to active oxygen clearance, including six upregulated and seven downregulated genes, alongside five fungal hydrophobic proteins, of which two genes were highly expressed. Our study provides high-quality genome information for the use of T. harzianum for biological control and offers significant insights into the molecular responses of T. harzianum under salt-stress conditions.
