Submicron particle extinction significantly contributed to reduced horizontal visibility during severe pollution episodes. However, seasonal variations in the scattering coefficients of chemical components, particularly with their size and mass concentration, are still not fully understood. This study investigated the scattering coefficients of the main chemical components of submicron particles (PM1) in Shanghai using advanced instruments. We discovered that the main scattering species exhibited seasonal variations. Notably, organics (OA) and ammonium sulfate ((NH4)2SO4) dominated in spring, summer, and autumn, whereas ammonium nitrate (NH4NO3) was the primary scattering species in winter. Analyzing the particle scattering coefficient size revealed that the scattering coefficients for OA in Shanghai exhibited bimodal distributions in spring, autumn, and winter, with peak sizes of 500-700 nm. The distribution was unimodal in summer, with a 400-500 nm peak size range. In addition, the peak particle size distributions of NH4NO3 and (NH4)2SO4 demonstrated a pattern of winter > spring/autumn > summer, potentially owing to the different species sources and formation pathways throughout the four seasons. Seasonal variations in the mass scattering efficiency (MSE) showed that OA exhibited a higher MSE than NH4NO3 or (NH4)2SO4. Further, NH4NO3 exhibited a higher MSE in winter, whereas (NH4)2SO4 exhibited the highest MSE in summer at 5.63. This study highlighted the importance of considering seasonal characteristics controlling scattered species and their precursors to enhance visibility. These findings can assist in formulating visibility control strategies in Shanghai.

Large-leaf yellow tea, a slightly fermented yellow tea that is unique to China, has a stronger hypoglycemic effect than other tea varieties, such as green and black tea. Research on large-leaf yellow tea has focused on its hypoglycemic effect owing to the lack of comprehensive techniques to characterize its chemical components; thus, its development and further promotion are limited. Therefore, the development of a reliable analytical method to fully characterize the chemical components of large-leaf yellow tea is urgently required. In this study, a reliable strategy based on the data-acquisition technology of ultra performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q TOF/MS) was established to rapidly screen and analyze the main chemical components of large-leaf yellow tea by combining the information of neutral loss groups and characteristic fragment ions. The chromatographic separation experiments were performed on a Waters ACQUITY UPLC BEH C18 column (100 mm×2.1 mm, 1.7 μm) with gradient elution using 0.1% formic acid aqueous solution and acetonitrile as the mobile phases. The flow rate was 0.2 mL/min, the sample volume was 2 μL, and the column temperature was 35 ℃. The mass spectral information of the components in a large-leaf yellow tea solution was collected using the full-information tandem MS (MSE) technique in positive and negative ion modes. The specific chemical components of large-leaf yellow tea was identified as follows. First, a self-established database of tea chemical components was constructed based on the literature. The mass spectral cleavage pathways of different types of compounds in large-leaf yellow tea were then sorted using reference substances, and the characteristics of the fragment ions and neutral loss groups were summarized. The precise mass-to-charge ratio of the target chemical components were then obtained based on the mass spectral information. Finally, the structures of the compounds in large-leaf yellow tea were confirmed based on their chromatographic retention times, mass spectral cleavage pathways, characteristic fragment ions, and neutral loss groups. A total of 87 chemical components, including 10 catechins, 32 flavonoids, 16 phenolic acids, 12 tannins, 6 theaflavins, and 11 compounds in other classes, were identified in large-leaf yellow tea. Representative compounds of various classes, including gallocatechin gallate, quercetin, vitexin, gallic acid, chlorogenic acid, 1,3,6-tri-O-galloyl-β-D-glucose, and theaflavin, were selected, and their characteristic fragment ions and neutral loss groups were investigated in detail to reveal the cleavage pathways of different types of compounds in large-leaf yellow tea. The UPLC-Q TOF/MS method established in this study can comprehensively identify the main chemical components of large-leaf yellow tea in a simple, highly sensitive, stable, and reliable manner. This study provides a scientific basis and data support for the discovery of functional ingredients and quality evaluation of large-leaf yellow tea.

Herbal medicines (HMs) have long played a pivotal role in preventing and treating various human diseases and have been studied widely. However, the complexities present in HM metabolites and their unclear mechanisms of action have posed significant challenges in the modernization of traditional Chinese medicine (TCM). Over the past two decades, mass spectrometry imaging (MSI) has garnered increasing attention as a robust analytical technique that enables the simultaneous execution of qualitative, quantitative, and localization analyses without complex sample pretreatment. With advances in technical solutions, MSI has been extensively applied in the field of HMs. MSI, a label-free ion imaging technique can comprehensively map the spatial distribution of HM metabolites in plant native tissues, thereby facilitating the effective quality control of HMs. Furthermore, the spatial dimension information of small molecule endogenous metabolites within animal tissues provided by MSI can also serve as a supplement to uncover pharmacological and toxicological mechanisms of HMs. In the review, we provide an overview of the three most common MSI techniques. In addition, representative applications in HM are highlighted. Finally, we discuss the current challenges and propose several potential solutions. We hope that the summary of recent findings will contribute to the application of MSI in exploring metabolites and mechanisms of action of HMs.

UNASSIGNED: Curing is a critical process that determines the sensory quality of cigars. The impact of oxygen on cigar curing and the mechanisms by which it regulates microbial changes affecting cigar quality are not well understood.
UNASSIGNED: In this study, we selected handmade cigars from the same batch and conducted curing experiments in environments with varying oxygen concentrations (equivalent to 0.1%, 6-12, and 15% of atmospheric oxygen concentration). We collected samples over 60 days and analyzed the distribution of microbial communities using high-throughput sequencing. Combined with the analysis of total sugars, proteins, flavor substances, and other chemical compounds, we elucidated how different oxygen concentrations affect the cigar curing process, influence microbial community succession, and ultimately impact cigar quality.
UNASSIGNED: Our results revealed significant differences in bacterial community composition under different oxygen conditions. Under aerobic conditions, Cyanobacteria were the dominant bacteria, while under oxygen-limited conditions, Staphylococcus and Corynebacterium predominated. As oxygen concentration decreased, so did the richness and diversity of the bacterial community. Conversely, oxygen concentration had a lesser impact on fungi; Aspergillus was the dominant genus in all samples. We also found that Enterococcus showed a positive correlation with aspartic acid, alanine, and 4-aminobutyric acid and a negative correlation with cysteine. Cigars cured at 15% oxygen concentration for 60 days exhibited optimal quality, particularly in terms of flavor richness and sweetness.
UNASSIGNED: These findings suggest that oxygen concentration can alter cigar quality by regulating aerobic and anaerobic microbial community succession. The relationship between specific microbial communities and flavor compounds also provides a theoretical reference for developing artificial control technologies in the cigar curing process.

Residential solid fuel combustion significantly impacts air quality and human health. Pelletized biomass fuels are promoted as a cleaner alternative, particularly for those who cannot afford the high costs of gas/electricity, but their emission characteristics and potential effects remain poorly understood. The present laboratory-based study evaluated pollution emissions from pelletized biomass burning, including CH4 (methane), NMHC (nonmethane hydrocarbon compounds), CO, SO2, NOx, PM2.5 (particulate matter with an aerodynamic diameter ≤2.5 μm), OC (organic carbon), EC (element carbon), PAHs (polycyclic aromatic hydrocarbons), EPFRs (environmentally persistent free radicals), and OP (oxidative potential) of PM2.5, and compared with those from raw biomass burning. For most targets, except for SO2 and NOx, the mass-based emission factors for pelletized biomass were 62-96% lower than those for raw biomass. SO2 and NOx levels were negatively correlated with other air pollutants (p < 0.05). Based on real-world daily consumption data, this study estimated that households using pelletized biomass could achieve significant reductions (51-95%) in emissions of CH4, NMHC, CO, PM2.5, OC, EC, PAHs, and EPFRs compared to those using raw biomass, while the differences in emissions of NOx and SO2 were statistically insignificant. The reduction rate of benzo(a)pyrene-equivalent emissions was only 16%, much lower than the reduction in the total PAH mass (78%). This is primarily attributed to the more PAHs with high toxic potentials, such as dibenz(a,h)anthracene, in the pelletized biomass emissions. Consequently, impacts on human health associated with PAHs might be overestimated if only the mass of total PAHs was counted. The OP of particles from the pellet burning was also significantly lower than that from raw biomass by 96%. The results suggested that pelletized biomass could be a transitional substitution option that can significantly improve air quality and mitigate human exposure.

BACKGROUND: Feining keli (FNKL) is herbal preparation mainly made from Senecio cannabifolius Less., In recent years, more and more studies have found that FNKL has excellent therapeutic effects on chronic bronchitis (CB). Nevertheless, its pharmacodynamic material basis and mechanism of action are still unknown.
OBJECTIVE: This study aimed to explore the pharmacodynamic material basis and mechanism of action of FNKL in treating CB.
METHODS: The CB rat model was induced using nasal drops of lipopolysaccharide (LPS) in combination with smoking. Various assessments including behavioral and body mass examination, lung index measurement, enzyme linked immunosorbent assay (ELISA), as well as histological analyses using hematoxylin and eosin (H&E) and Masson staining were conducted to validate the reliability of the CB model. The serum components of FNKL in CB rats were identified using ultra-high-performance liquid chromatography Orbitrap Exploris mass spectrometer (UHPLC-OE-MS). Network pharmacology was used to predict the network of action of the active ingredients in FNKL based on these serum components. Signaling pathways were enriched and analyzed, and molecular docking was conducted for key targets. Molecular dynamics simulations were performed using GROMACS software. The mechanism was confirmed through a series of experiments including Western blot (WB), immunofluorescence (IF), and reverse transcription (RT)-PCR. Additionally, untargeted metabolomics was employed to identify biomarkers and relevant metabolic pathways associated with the treatment of CB with FNKL.
RESULTS: In CB rats, FNKL improved body mass, lung index, and pathological damage of lung tissues. It also decreased interleukin (IL)-6, tumor necrosis factor-alpha (TNF-α), malonaldehyde (MDA) levels, and percentage of lung collagen fiber area. Furthermore, FNKL increased IL-10 and superoxide dismutase (SOD) levels, which helped alleviate bronchial inflammation in the lungs. A total of 70 FNKL chemical components were identified in CB rat serum. Through network pharmacology analysis, 5 targets, such as PI3K, AKT, NF-κB, HIF-1α, and MYD88, were identified as key targets of FNKL in the treatment of CB. Additionally, the key signaling pathways identified were PI3K/AKT pathway、NF-κB/MyD88 pathway、HIF-1α pathway. WB, IF, and RT-PCR experiments were conducted to confirm the findings. Molecular docking studies demonstrated successful docking of 16 potential active components with 5 key targets. Additionally, molecular dynamics simulations indicated the stability of quercetin-3-galactoside and HIF-1α. Metabolomics analysis revealed that FNKL primarily regulated pathways related to alpha-linolenic acid metabolism, primary bile acid biosynthesis, bile secretion, arachidonic acid metabolism, neuroactive ligand-receptor interaction, and folate biosynthesis. Furthermore, the expression levels of traumatic acid, traumatin, alpha linolenic acid, cholic acid, 2-arachidonoylglycerol, deoxycholic acid, 7,8-dihydroneopterin, and other metabolites were found to be regulated.
CONCLUSIONS: FNKL exhibits positive therapeutic effects on CB, with quercetin-3-galactoside identified as a key active component. The mechanism of FNKL\'s therapeutic action on CB involves reducing inflammatory response, oxidative stress, and regulating metabolism, and its molecular mechanism was better elucidated in a holistic manner. This study serves as a reference for understanding the pharmacodynamic material basis and mechanism of action of FNKL in treating CB, and provides avenues for exploring the effects of compounded herbal medicines on CB.

The method of ultra-high performance liquid chromatography-quadrupole-electrostatic field orbitrap high-resolution mass spectrometry(UHPLC-Q/Orbitrap HRMS)combined with molecular network was developed in this study for rapidly analyzing the chemical components of the Qinggu San reference sample of classical prescription. Firstly, an ACQUITY UPLC BEH Shield RP_(18) column(2.1 mm×100 mm, 1.7 μm)was used, and acetonitrile and 0.1% formic acid were taken as the mobile phases for gradient elution. The flow rate was 0.4 mL·min~(-1), and the column temperature was 30 ℃. Under these conditions, the mass spectrum data were collected in both positive and negative ion modes of the heated electrospray ionization source. Subsequently, the mass spectrum data of the Qinggu San reference sample were uploaded to the Global Natural Products Social Molecular Network(GNPS)platform for calculation and analysis, and a visual molecular network was built with Cytoscape 3.8.2 software. On this basis, the chemical components of the Qinggu San reference sample were identified by fragmentation regularity of standard compounds, retention time, accurate relative molecular weight of HR-MS, characteristic fragment ions information, literature, and databases. Finally, a total of 105 chemical components were identified and speculated in the Qinggu San reference sample, including 19 iridoid glycosides, 23 flavonoids, 15 phenylpropanoids, 11 triterpene saponins, and 37 other components. Meanwhile, two of these components are potential new compounds. The method used in this study not only achieved rapid and accurate identification of chemical components in the Qinggu San reference sample and provided a scie-ntific basis for the study of pharmacological substances and quality control of Qinggu San compound preparations but also provided a refe-rence for the rapid identification of chemical components in traditional Chinese medicine compound preparations.

The artificial cultivation and management were extensively carried out in Dendrocalamus brandisii stands. However, the influences of artificial management on the anatomical and chemical characteristics of the bamboo culms were unknown. In this study, the fiber morphology, chemical composition and sugar accumulation of the D. brandisii culms with management and without management were compared in order to determine the influences of artificial management on bamboo culms. The results indicated that artificial management had a significant influence on the fiber morphology, resulting in shorter fiber length, larger L/T ratio, and smaller W/Lu value. However, the management not only increased the contents of moisture, ash, SiO2, and extractive, but also increased the holocellulose contents and decreased the lignin contents, as compared to those without management. Moreover, the management significantly increased the endogenous carbohydrates storage in the culms so as to improve the shoot production. The bamboos under management conditions could still be utilized as a raw material for papermaking. This provided a theoretical basis for the artificial management of D. brandisii stands.

UNASSIGNED: Polygonum multiflorum Thunb. (PM), a kind of perennial plant, belongs to the genus Polygonum of the family polygonaceae.The dry root of PM (also called Heshouwu), is a traditional Chinese medicine, which has a series of functions and is widely used in clinic for hair lossing, aging, and insomnia. While, PM also has some toxicity, its clinical drug safety has been concerned. In this paper, the chemical components, toxic mechanisms and detoxification strategies of PM were reviewed in order to provide evidence for its clinical application.
UNASSIGNED: We conducted a systematic review of published literature of PM, including English and Chinese databases, such as PubMed, Web of Science, CNKI, and Wanfang.
UNASSIGNED: PM contains a variety of chemical compounds, including stilbenes, quinones, flavonoids, phospholipids, and has many pharmacological activities such as anti-aging, wound healing, antioxidant, and anti-inflammatory properties. The PE has certain therapeutic effect, and it has certain toxicity like hepatotoxicity, nephrotoxicity, and embryotoxicity at the same time, but.these toxic effects could be effectively reduced by processing and compatibility.
UNASSIGNED: It is necessary to further explore the pharmacological and toxicological mechanisms of the main active compounds of PE.This article provides scientific basis for the safe clinical application of PM.

BACKGROUND: The genus L. has high medicinal value and has traditional been used to treat a variety of gastrointestinal disorders, as well as diabetes, edema, colds, arthritis, asthma, and traumatic injuries.
OBJECTIVE: This work addresses the missing information by conducting a comprehensive analysis of the traditional uses, chemical components, and pharmacological applications of the more reported species of the genus L. The origin of the genus, its toxicology, and the use of classical therapies in modern medicine were also discussed. It provides references for historical evidence, resource development, and medical research on the genus.
METHODS: ology: Data about the genus L. were gathered via Web of Science, PubMed, Science Direct, Google Scholar, Connected Papers, China National Knowledge Infrastructure (CNKI), electronic ancient books and local chronicles. The WFO Plant List (wfoplantlist.org) and Flora of China (www.iplant.cn) confirmed L.\'s Latin name, and the species information. The program ChemBioDraw Ultra 14.0 was used to create the molecular structures of the compounds that were displayed in the text.
RESULTS: Currently, at least 740 constituents have been isolated and identified from L. These include 9 groups of chemicals, such as flavonoids, alkaloids, and terpenoids. They have been shown to have over 20 biological properties in vivo and in vitro, such as antibacterial, anti-inflammatory, and anti-oxidant effects.
CONCLUSIONS: Based on pharmacological investigations, chemical components, and traditional folk applications, L. is considered a medicinal plant having a variety of pharmacological actions. However, although the pharmacological activity of the L. genus has been preliminary demonstrated, most have only been assessed using simple in vitro cell lines or animal disease models. In order to fully elucidate the pharmacological activity and mechanisms of L., future studies should be conducted in a more comprehensive clinical manner.