Modulation of gut microbiota and metabolites by Flammulina velutipes polysaccharides during in vitro human fecal fermentation: Unveiling Bacteroides as a potential primary degrader.

Flammulina velutipes, a widely cultivated species of edible fungus, exhibits diverse functional activities attributed to its polysaccharides. In this study, we employed an in vitro model to investigate the impact of F. velutipes polysaccharides (FVP) fermentation on gut microbiota, with a particular focus on Bacteroides. FVP fermentation resulted in the proliferation of microbiota associated with short-chain fatty acid (SCFA) metabolism and suppression of Escherichia-Shigella. Bacteroides emerged as potential primary degraders of FVP, with species-level analysis identifying the preference of B. thetaiotaomicron and B. intestinalis in FVP degradation. Metabolomics analysis revealed significant increases in hypoxanthine and 7-methyladenine contents, with histidine metabolism emerging as the most enriched pathway. B. nordii and B. xylanisolvens exhibited the most influence on amino acid and SCFA metabolism. Understanding the mechanisms by which gut microbiota metabolize FVP can provide valuable insights into the potential of FVP to promote intestinal health and disease prevention.

Advances in encapsulation systems of Antarctic krill oil: From extraction to encapsulation, and future direction.

Antarctic krill oil (AKO) is highly sought after by consumers and the food industry due to its richness in a variety of nutrients and physiological activities. However, current extraction methods are not sufficient to better extract AKO and its nutrients, and AKO is susceptible to lipid oxidation during processing and storage, leading to nutrient loss and the formation of off-flavors and toxic compounds. The development of various extraction methods and encapsulation systems for AKO to improve oil yield, nutritional value, antioxidant capacity, and bioavailability has become a research hotspot. This review summarizes the research progress of AKO from extraction to encapsulation system construction. The AKO extraction mechanism, technical parameters, oil yield and composition of solvent extraction, aqueous enzymatic extraction, supercritical/subcritical extraction, and three-liquid-phase salting-out extraction system are described in detail. The principles, choice of emulsifier/wall materials, preparation methods, advantages and disadvantages of four common encapsulation systems for AKO, namely micro/nanoemulsions, microcapsules, liposomes and nanostructured lipid carriers, are summarized. These four encapsulation systems are characterized by high encapsulation efficiency, low production cost, high bioavailability and high antioxidant capacity. Depending on the unique advantages and conditions of different encapsulation methods, as well as consumer demand for health and nutrition, different products can be developed. However, existing AKO encapsulation systems lack relevant studies on digestive absorption and targeted release, and the single product category of commercially available products limits consumer choice. In conjunction with clinical studies of AKO encapsulation systems, the development of encapsulation systems for special populations should be a future research direction.

Tandem Catalysts Enabling Efficient C-N Coupling toward the Electrosynthesis of Urea.

The development of a methodology for synthesizing value-added urea (CO(NH2)2) via a renewable electricity-driven C-N coupling reaction under mild conditions is highly anticipated. However, the complex catalytic active sites that act on the carbon and nitrogen species make the reaction mechanism unclear, resulting in a low efficiency of C-N coupling from the co-reduction of carbon dioxide (CO2) and nitrate (NO3 -). Herein, we propose a novel tandem catalyst of Mo-PCN-222(Co), in which the Mo sites serve to facilitate nitrate reduction to the *NH2 intermediate, while the Co sites enhance CO2 reduction to carbonic oxide (CO), thus synergistically promoting C-N coupling. The synthesized Mo-PCN-222(Co) catalyst exhibited a noteworthy urea yield rate of 844.11 mg h-1 g-1, alongside a corresponding Faradaic efficiency of 33.90 % at -0.4 V vs. reversible hydrogen electrode (RHE). By combining in situ spectroscopic techniques with density functional theory calculations, we demonstrate that efficient C-N coupling is attributed to a tandem system in which the *NH2 and *CO intermediates produced by the Mo and Co active sites of Mo-PCN-222(Co) stabilize the formation of the *CONH2 intermediate. This study provides an effective avenue for the design and synthesis of tandem catalysts for electrocatalytic urea synthesis.

Distribution of coronal plane alignment of the knee classification in Chinese osteoarthritic and healthy population: a retrospective cross-sectional observational study.

BACKGROUND: Few studies have reported the coronal constitutional alignment of the lower limbs in mainland China. This study aimed to analyse the distribution of the coronal plane alignment of the knee (CPAK) classification in the osteoarthritic and healthy Chinese populations. MATERIALS AND METHODS: The CPAK distributions of 246 patients (477 knees) with osteoarthritis (OA) and 107 healthy individuals (214 knees) were retrospectively examined using long-leg radiographs. Radiological measurements and CPAK classification of different Kellgren-Lawrence grades in patients with unilateral total knee arthroplasty (TKA) were compared. The clinical outcomes of patients with CPAK type I who underwent mechanical alignment or restricted kinematic alignment during TKA were examined. RESULTS: The most common distributions in the OA and healthy groups were type I and type II, respectively. In patients who underwent unilateral TKA, the most common distribution of knees graded as Kellgren-Lawrence 3-4 was type I. However, the most common distributions of contralateral knees graded as Grade 0-2 were type I and II. For patients with CPAK type I, the mechanical alignment and restricted kinematic alignment groups did not differ significantly concerning postoperative clinical outcomes at three months. CONCLUSION: The most common distributions in Chinese osteoarthritic and healthy populations were types I and II, respectively. In addition, OA progression may lead to changes in the CPAK classification.

Factors Influencing Noise Following Primary Ceramic-on-Ceramic Total Hip Arthroplasty.

BACKGROUND: The noise associated with ceramic-on-ceramic (CoC) total hip arthroplasty (THA) has been a concerning issue, while its underlying causes remain unclear. METHODS: We conducted a retrospective analysis of 119 patients (174 primary CoC THAs) who had a mean follow-up of 28 months (range, 12 to 106). A questionnaire was designed to collect information on nature, frequency, onset, duration, and impact of the noise. Postoperative x-rays were evaluated. Clinical evaluations, including Harris and Oxford hip scores, were documented at follow-up time points (6 weeks, 3 months, 6 months, and 1 year). RESULTS: Of the 174 hips, 31.6% reported noise, including 26 popping (14.9%), 24 clicking (12.1%), and 5 grinding (2.9%). No patients reported squeaking. Noisy hips had lower age (P = .009) and body mass index (P = .019). Among patients with developmental dysplasia of the hip, 17 of 55 hips reported noise associated with smaller cup anteversion angle (P = .004), greater body height (P = .022), and larger acetabular cup size (P = .049). Noise typically began at a mean of 193 days (range, 1 to 2,598) after surgery and disappeared spontaneously in 50.9% of hips before final follow-up, with an average disappearance time of 211 days (range, 60 to 730). Noise did not affect daily life in 74.5% of patients, while 26.9% of patients who had popping reported painful sensations. One patient experienced joint dislocation, and another experienced a ceramic liner fracture during follow-up. No statistical difference was observed in outcome scores between noise and silent groups at 4 follow-up time points. CONCLUSIONS: Incidence of noise after primary CoC THA is relatively high. Smaller cup anteversion and larger acetabular cup size were associated with noise production in patients who had developmental dysplasia of the hip.

Biotransformation of American Ginseng Stems and Leaves by an Endophytic Fungus Umbelopsis sp. and Its Effect on Alzheimer's Disease Control.

BACKGROUND: Common ginsenosides can be transformed into rare ginsenosides through microbial fermentation, and some rare ginsenosides can prevent Alzheimer's disease (AD). This study aimed to transform common ginsenosides into rare ginsenosides through solid-state fermentation of American ginseng stems and leaves (AGSL) by an endophytic fungus and to explore whether fermented saponin extracts prevent AD. METHODS: The powders of AGSL were fermented in a solid state by endophytic fungus. Total saponins were extracted from fermentation products using the methanol extraction method. The types of saponins were analyzed by liquid chromatography mass spectrometry (LC/MS). The Aß42 concentration and ß-secretase activity were measured by ELISA for the prevention of AD. RESULTS: After AGSL was fermented by an endophytic fungus NSJG, the total saponin concentration of the fermented extract G-SL was higher than the unfermented CK-SL. Rare ginsenoside Rh1 was newly produced and the yield of compound K (561.79%), Rh2 (77.48%), and F2 (40.89%) was increased in G-SL. G-SL had a higher inhibition rate on Aß42 concentration (42.75%) and ß-secretase activity (42.22%) than CK-SL, possibly because the rare ginsenoside Rh1, Rh2, F2, and compound K included in it have a strong inhibitory effect on AD. CONCLUSION: The fermented saponin extracts of AGSL show more inhibition effects on AD and may be promising therapeutic drugs or nutrients for AD.

Intrinsic surface p-wave superconductivity in layered AuSn4.

The search for topological superconductivity (TSC) is currently an exciting pursuit, since non-trivial topological superconducting phases could host exotic Majorana modes. However, the difficulty in fabricating proximity-induced TSC heterostructures, the sensitivity to disorder and stringent topological restrictions of intrinsic TSC place serious limitations and formidable challenges on the materials and related applications. Here, we report a new type of intrinsic TSC, namely intrinsic surface topological superconductivity (IS-TSC) and demonstrate it in layered AuSn4 with Tc of 2.4 K. Different in-plane and out-of-plane upper critical fields reflect a two-dimensional (2D) character of superconductivity. The two-fold symmetric angular dependences of both magneto-transport and the zero-bias conductance peak (ZBCP) in point-contact spectroscopy (PCS) in the superconducting regime indicate an unconventional pairing symmetry of AuSn4. The superconducting gap and surface multi-bands with Rashba splitting at the Fermi level (EF), in conjunction with first-principle calculations, strongly suggest that 2D unconventional SC in AuSn4 originates from the mixture of p-wave surface and s-wave bulk contributions, which leads to a two-fold symmetric superconductivity. Our results provide an exciting paradigm to realize TSC via Rashba effect on surface superconducting bands in layered materials.

Comparison between Hematology and Serum Biochemistry of Qinling and Sichuan Giant Panda (Ailuropoda melanoleuca qinlingensis and sichuanensis).

Giant pandas are the flagship species in world conservation, and include two subspecies, Ailuropoda melanoleuca qinlingensis (A. m. qinlingensis) and Ailuropoda melanoleuca sichuanensis (A. m. sichuanensis). Hematology and serum biochemistry studies are crucial to protecting giant pandas. Even though research on hematology and serum biochemistry are well-established in A. m. sichuanensis, research in A. m. qinlingensis is scarce. The study aimed to (1) establish a baseline for hemogram and reference intervals (RIs) for hematological and serum biochemical parameters in A. m. qinlingensis, (2) assess the possible variations in these parameters of A. m. qinlingensis based on age, gender, and storage condition of blood samples, and (3) compare the parameters to those of A. m. sichuanensis. Blood samples (n = 42) were collected from healthy A. m. qinlingensis (n = 21) housed in Shaanxi (Louguantai) Rare Wildlife Rescue and Breeding Research Center, and hematological (n = 25) and serum biochemical parameters (n = 18) were analyzed in March and December of 2019. The results showed no significant abnormality in the blood smears of all individuals in this study, except for a few serrated red blood cells, platelet aggregations, and occasionally giant platelets. Between sub-adult and adult A. m. qinlingensis, there were significant differences in five hematological and one serum biochemical parameter (p < 0.05), whereas six serum biochemical parameters were present when α = 0.1 (p < 0.1). Gender influenced % NEU, % LYM, % EOS, LYM, EOS, GGT, and CHOL of A. m. qinlingensis. The majority of the hematological and serum biochemical parameters of A. m. qinlingensis were different from those of A. m. sichuanensis regarding age and gender. The anticoagulant whole blood samples of A. m. qinlingensis stored at 2-8 °C for 24 h and the serum samples stored at -18 °C for 48 h had little influence on the values of hematological and serum biochemical parameters. In conclusion, this study provided a baseline of hemogram and established RIs for hematological and serum biochemical parameters of A. m. qinlingensis. RIs of A. m. sichuanensis reported before were not completely fit for A. m. qinlingensis, and age, gender, or the storage condition of blood samples influenced some of the parameters of A. m. qinlingensis. To the authors' knowledge, this is the first report of a hemogram baseline and RIs for hematological and serum biochemical parameters of A. m. qinlingensis.

Editorial for the Special Issue: "Spatial Structure of Minerals".

The spatial structure of minerals is a fundamental factor in determining the morphology, physical properties, and genesis of minerals [...].

Optimization of Fermentation Conditions and Product Identification of a Saponin-Producing Endophytic Fungus.

BACKGROUND: Some fungal endophytes isolated from P. ginseng may present a new method of obtaining saponins. This experiment aimed to optimize the total saponin yield produced through in vitro fermentation by an endophytic fungus and analyze its saponin species in the fermented extract. METHODS: Fermentation protocols were optimized with a uniform design and verified through regression analysis to maximize the total saponin yield. The saponin types under optimal fermentation conditions were then identified and analyzed using Liquid Chromatography-Mass Spectrometry. RESULTS: The Trametes versicolor strain NSJ105 (gene accession number: OR144428) isolated from wild ginseng could produce total saponins. The total saponin yield could be increased more than two-fold through the optimization of fermentation conditions. The concentration of the total saponins achieved by the verified protocol 105-DP was close to the predicted value. The fermentation conditions of the 105-DP protocol were as follows: potato concentration 97.3 mg/mL, glucose concentration 20.6 mg/mL, inoculum volume 2.1%, fermentation broth pH 2.1, fermentation temperature 29.2 °C, and fermentation time 6 d. It was detected and analyzed that the fermented extract of 105-DP contained the ginsenosides Rf and Rb3. CONCLUSION: The endophytic fungus Trametes versicolor strain NSJ105 has potential application value in saponin production.

A Simple Molecular Design Strategy for Luminescent Radicals to Achieve Near-Infrared Emission.

The spin-allowed doublet emission of luminescent radicals has recently attracted significant attention. However, the spectral range of most reported luminescent radical emitters and their corresponding organic light-emitting diodes (OLEDs) is confined to the red and deep red regions, with only a few extending to the near-infrared region, specifically in the context of an emission peak exceeding 800 nm. Herein, a luminescent radical, 2-(4-(bis(2,4,6-trichlorophenyl)methyl radical)-3,5-dichlorophenyl)-4-phenyl-4H-thieno[3,2-b]indole (TTM-2PTI), with NIR emission peaking at 830 nm in toluene, was obtained through attaching a 4-phenyl-4H-thieno[3,2-b]indole group to the TTM radical core. An organic light-emitting diode (OLED) utilizing TTM-2PTI as the emitter exhibits electroluminescence (EL) emission peaking at 870 nm, which is the longest EL wavelength among the doublet-emissive near-infrared (NIR) OLEDs. This work provides a simple molecular design strategy to achieve NIR emission of radicals by leveraging the lower steric hindrance and electron-donating ability of thiophene.

A Novel Strategy for the Demulsification of Peanut Oil Body by Caproic Acid.

The aqueous enzymatic method is a form of green oil extraction technology with limited industrial application, owing to the need for the demulsification of the oil body intermediate product. Existing demulsification methods have problems, including low demulsification rates and high costs, such that new methods are needed. The free fatty acids produced by lipid hydrolysis can affect the stability of peanut oil body (POB) at a certain concentration. After screening even-carbon fatty acids with carbon chain lengths below ten, caproic acid was selected for the demulsification of POB using response surface methodology and a Box-Behnken design. Under the optimal conditions (caproic acid concentration, 0.22%; solid-to-liquid ratio, 1:4.7 (w/v); time, 61 min; and temperature, 79 °C), a demulsification rate of 97.87% was achieved. Caproic acid not only adjusted the reaction system pH to cause the aggregation of the POB interfacial proteins, but also decreased the interfacial tension and viscoelasticity of the interfacial film with an increasing caproic acid concentration to realize POB demulsification. Compared to pressed oil and soxhlet-extracted oil, the acid value and peroxide value of the caproic acid demulsified oil were increased, while the unsaturated fatty acid content and oxidation induction time were decreased. However, the tocopherol and tocotrienol contents were higher than those of the soxhlet-extracted oil. This study provides a new method for the demulsification of POB.

Genetic mapping of the wheat leaf rust resistance gene Lr19 and development of translocation lines to break its linkage with yellow pigment.

KEY MESSAGE: The leaf rust resistance gene Lr19, which is present on the long arm of chromosome 7E1 in Thinopyrum ponticum, was mapped within a 0.3-cM genetic interval, and translocation lines were developed to break its linkage with yellow pigmentation The leaf rust resistance locus Lr19, which was transferred to wheat (Triticum aestivum) from its relative Thinopyrum ponticum in 1966, still confers broad resistance to most known races of the leaf rust pathogen Puccinia triticina (Pt) worldwide. However, this gene has not previously been fine-mapped, and its tight linkage with a gene causing yellow pigmentation has limited its application in bread wheat breeding. In this study, we genetically mapped Lr19 using a bi-parental population from a cross of two wheat-Th. ponticum substitution lines, the Lr19-carrying line 7E1(7D) and the leaf rust-susceptible line 7E2(7D). Genetic analysis of the F2 population and the F2:3 families showed that Lr19 was a single dominant gene. Genetic markers allowed the gene to be mapped within a 0.3-cM interval on the long arm of Th. ponticum chromosome 7E1, flanked by markers XsdauK3734 and XsdauK2839. To reduce the size of the Th. ponticum chromosome segment carrying Lr19, the Chinese Spring Ph1b mutant was employed to promote recombination between the homoeologous chromosomes of the wheat chromosome 7D and the Th. ponticum chromosome 7E1. Two translocation lines with short Th. ponticum chromosome fragments carrying Lr19 were identified using the genetic markers closely linked to Lr19. Both translocation lines were resistant to 16 Pt races collected throughout China. Importantly, the linkage between Lr19 and yellow pigment content was broken in one of the lines. Thus, the Lr19 linked markers and translocation lines developed in this study are valuable resources in marker-assisted selection as part of common wheat breeding programs.

Interaction of beta-glucans with gut microbiota: Dietary origins, structures, degradation, metabolism, and beneficial function.

Beta-glucan (BG), a polysaccharide comprised of interfacing glucose monomers joined via beta-glycosidic linkages, can be defined as a type of dietary fiber with high specificity based on its interaction with the gut microbiota. It can induce similar interindividual microbiota responses, thereby having beneficial effects on the human body. In this paper, we review the four main sources of BG (cereals, fungi, algae, and bacteria) and their differences in structure and content. The interaction of BG with gut microbiota and the resulting health effects have been highlighted, including immune enhancement, regulation of serum cholesterol and insulin levels, alleviation of obesity and improvement of cognitive disorders. Finally, the application of BG in food products and its beneficial effects on the gut microbiota of consumers were discussed. Although some of the mechanisms of action remain unclear, revealing the beneficial functions of BG from the perspective of gut microbiota can help provide theoretical support for the development of diets that target the regulation of microbiota.

Engineering Spin States of Isolated Copper Species in a Metal-Organic Framework Improves Urea Electrosynthesis.

The catalytic activities are generally believed to be relevant to the electronic states of their active center, but understanding this relationship is usually difficult. Here, we design two types of catalysts for electrocatalytic urea via a coordination strategy in a metal-organic frameworks: CuIII-HHTP and CuII-HHTP. CuIII-HHTP exhibits an improved urea production rate of 7.78 mmol h-1 g-1 and an enhanced Faradaic efficiency of 23.09% at - 0.6 V vs. reversible hydrogen electrode, in sharp contrast to CuII-HHTP. Isolated CuIII species with S = 0 spin ground state are demonstrated as the active center in CuIII-HHTP, different from CuII with S = 1/2 in CuII-HHTP. We further demonstrate that isolated CuIII with an empty [Formula: see text] orbital in CuIII-HHTP experiences a single-electron migration path with a lower energy barrier in the C-N coupling process, while CuII with a single-spin state ([Formula: see text]) in CuII-HHTP undergoes a two-electron migration pathway.

Prevention of Pregabalin-Related Side Effects Using Slow Dose Escalation Before Surgery: A Trial in Primary Total Joint Arthroplasty Within the Enhanced Recovery After Surgery Pathway.

BACKGROUND: The side effects of pregabalin likely occur after the first dose. We aimed to evaluate the effect of 75 milligrams (mg) of pregabalin prescribed as an initial dose with a slow dose escalation for primary total joint arthroplasty within the enhanced recovery after surgery pathway. METHODS: Participants were randomly assigned to two groups. Fifty-eight patients were enrolled, and twenty-nine were assigned to each group. Group 1 (G1) received pregabalin (37.5 mg) twice on the day before surgery, as well as pregabalin 75 mg two hours pre-operatively; Group 2 (G2) received none on the day before surgery and the same dose of pregabalin at two hours pre-operatively. The primary outcome was dizziness assessed by severity; secondary outcomes included nausea, vomiting, sedation, opioid consumption, independent transfer at six hours post-operatively, time to readiness for independent transfers, time to readiness for discharge, and pain. RESULTS: At two, four, and six hours post-operatively, the proportion of patients experiencing dizziness and nausea was significantly greater in G2 than in G1, and opioid consumption was significantly greater in G2 than in G1 (P = .012). The proportion of independent transfers at six hours post-operatively was significantly greater in G1 than in G2 (P = .010). The time to readiness for independent transfers was significantly shorter in G1 than in G2 (P = .016). CONCLUSION: Prescription of pregabalin 37.5 mg twice on the day before surgery was effective in reducing early postoperative dizziness and nausea after receiving pregabalin 75 mg two hours pre-operatively. It also promoted early independent transfers and reduced opioid consumption.

Towards Efficient and Stable Donor-Acceptor Luminescent Radicals.

In contrast to closed-shell luminescent molecules, the electronic ground state and lowest excited state in organic luminescent radicals are both spin doublet, which results in spin-allowed radiative transitions. Most reported luminescent radicals with high photoluminescent quantum efficiency (PLQE) have a donor-acceptor (D-A•) chemical structure where an electron-donating group is covalently attached to an electron-withdrawing radical core (A•). Understanding the main factors that define the efficiency and stability of D-A• type luminescent radicals remains challenging. Here, we designed and synthesized a series of tri(2,4,6-trichlorophenyl)methyl (TTM) radical derivatives with donor substituents varying by their extent of conjugation and their number of imine-type nitrogen atoms. The experimental results suggest that the luminescence efficiency and stability of the radicals are proportional to the degree of conjugation but inversely proportional to the number of imine nitrogen atoms in the substituents. These experimental trends are very well reproduced by density functional theory calculations. The theoretical results indicate that both the luminescence efficiency and radical stability are related to the energy difference between the charge transfer (CT) and local-excitation (LE) states, which decreases as either the number of imine nitrogen atoms in the substituent increases or its conjugation length decreases.

Single-Atom or Dual-Atom in TiO2 Nanosheet: Which is the Better Choice for Electrocatalytic Urea Synthesis?

As rising star materials, single-atom and dual-atom catalysts have been widely reported in the electro-catalysis area. To answer the key question: single-atom and dual-atom catalysts, which is better for electrocatalytic urea synthesis? we design two types of catalysts via a vacancy-anchorage strategy: single-atom Pd1 -TiO2 and dual-atom Pd1 Cu1 -TiO2 nanosheets. An ultrahigh urea activity of 166.67 molurea molPd -1 h1 with the corresponding 22.54 % Faradaic efficiency at -0.5 V vs. reversible hydrogen electrode (RHE) is achieved over Pd1 Cu1 -TiO2 , which is much higher than that of Pd1 -TiO2 . Various characterization including an in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and theoretical calculations demonstrate that dual-atom Pd1 Cu1 site in Pd1 Cu1 -TiO2 is more favorable for producing urea, which experiences a C-N coupling pathway with a lower energy barrier compared with Pd1 in Pd1 -TiO2 .

Facet-Dependent SERS Activity of Co3O4.

Surface-enhanced Raman spectroscopy (SERS) is an ultra-sensitive and rapid technique that is able to significantly enhance the Raman signals of analytes absorbed on functional substrates by orders of magnitude. Recently, semiconductor-based SERS substrates have shown rapid progress due to their great cost-effectiveness, stability and biocompatibility. In this work, three types of faceted Co3O4 microcrystals with dominantly exposed {100} facets, {111} facets and co-exposed {100}-{111} facets (denoted as C-100, C-111 and C-both, respectively) are utilized as SERS substrates to detect the rhodamine 6G (R6G) molecule and nucleic acids (adenine and cytosine). C-100 exhibited the highest SERS sensitivity among these samples, and the lowest detection limits (LODs) to R6G and adenine can reach 10-7 M. First-principles density functional theory (DFT) simulations further unveiled a stronger photoinduced charge transfer (PICT) in C-100 than in C-111. This work provides new insights into the facet-dependent SERS for semiconductor materials.

Integrated untargeted fecal metabolomics and gut microbiota strategy for screening potential biomarkers associated with schizophrenia.

Schizophrenia (SZ) is a serious neurodevelopmental disorder. As the etiology of SZ is complex and the pathogenesis is not thoroughly understood, the diagnosis of different subtypes still depends on the subjective judgment of doctors. Therefore, there is an urgent need to develop early objective laboratory diagnostic biomarkers to screen different subtypes of patients as early as possible, and to implement targeted prevention and precision medicine to reduce the risk of SZ and improve patients' quality of life. In this study, untargeted metabolomics and 16S rDNA sequencing were used to analyze the differences in metabolites and gut microflora among 28 patients with two types of schizophrenia and 11 healthy subjects. The results showed that the metabolome and sequencing data could effectively discriminate among paranoid schizophrenia patients, undifferentiated schizophrenia patients and healthy controls. We obtained 65 metabolites and 76 microorganisms with significant changes, and fecal metabolite composition was significantly correlated with the differential genera (|r|>0.5), indicating that there was a regulatory relationship between the gut microbiota and the host metabolites. The gut microbiome, as an objective and measurable index, showed good diagnostic value for distinguishing schizophrenia patients from healthy people, especially with a combination of several differential microorganisms, which had the best diagnostic effect (AUC>0.9). Our results are conducive to understanding the complicated metabolic changes in SZ patients and providing valuable information for the clinical diagnosis of SZ.