Phytochemical Profile and Bioactivity of Bound Polyphenols Released from Rosa roxburghii Fruit Pomace Dietary Fiber by Solid-State Fermentation with Aspergillus niger.

This study aimed to investigate the phytochemical profile, bioactivity, and release mechanism of bound polyphenols (BPs) released from Rosa roxburghii fruit pomace insoluble dietary fiber (RPDF) through solid-state fermentation (SSF) with Aspergillus niger. The results indicated that the amount of BPs released from RPDF through SSF was 17.22 mg GAE/g DW, which was significantly higher than that achieved through alkaline hydrolysis extraction (5.33 mg GAE/g DW). The BPs released through SSF exhibited superior antioxidant and α-glucosidase inhibitory activities compared to that released through alkaline hydrolysis. Chemical composition analysis revealed that SSF released several main compounds, including ellagic acid, epigallocatechin, p-hydroxybenzoic acid, quercetin, and 3,4-dihydroxyphenylpropionic acid. Mechanism analysis indicated that the disruption of tight structure, chemical bonds, and hemicellulose was crucial for the release of BPs from RPDF. This study provides valuable information on the potential application of SSF for the efficient release of BPs from RPDF, contributing to the utilization of RPDF as a functional food ingredient.

Pulsed electric field-assisted extraction of hesperidin from tangerine peel and its technological optimization through response surface methodology.

BACKGROUND: Tangerine peel is rich in flavonoids, particularly hesperidin, which has anti-inflammatory, antioxidant and anticancer biological activities. However, it is often wasted during citrus processing. The current common extraction method for hesperidin is solvent extraction, which has the characteristics of low extraction rate and high contamination. The aim of this study was to investigate the effect of pulsed electric field-assisted alkali dissolution extraction, followed by an acidification precipitation method, on the extraction rate and structure of hesperidin from tangerine peel. RESULTS: The results showed that the selected factors (material/liquid ratio, electric field intensity and pulse number) had a significant effect on the extraction yield. An optimum condition of 66.00 mL g-1, 4.00 kV cm-1 and 35.00 pulses gave the maximum amount (669.38 µg mL-1), which was consistent with the theoretically predicted value by software (672.10 µg mL-1), indicating that the extraction process was feasible. In addition, the purified extract was further identified as hesperidin from UV and NMR spectra. CONCLUSION: An appropriate strength of pulsed electric field-assisted alkali dissolution extraction followed by an acidification precipitation method can effectively improve the extraction rate of orange peel, and the purity of the extracted orange peel is higher. Compared with the traditional extraction, the pulsed electric field-assisted extraction method may be a potential technology for hesperidin extraction, which is beneficial for the high-value utilization of citrus resources. © 2024 Society of Chemical Industry.

Development, External Validation, and Visualization of Machine Learning Models for Predicting Occurrence of Acute Kidney Injury after Cardiac Surgery.

Background: Cardiac surgery-associated acute kidney injury (CSA-AKI) is a major complication that results in short- and long-term mortality among patients. Here, we adopted machine learning algorithms to build prediction models with the overarching goal of identifying patients who are at a high risk of such unfavorable kidney outcomes. Methods: A total of 1686 patients (development cohort) and 422 patients (validation cohort), with 126 pre- and intra-operative variables, were recruited from the First Medical Centre and the Sixth Medical Centre of Chinese PLA General Hospital in Beijing, China, respectively. Analyses were performed using six machine learning techniques, namely K-nearest neighbor, logistic regression, decision tree, random forest (RF), support vector machine, and neural network, and the APPROACH score, a previously established risk score for CSA-AKI. For model tuning, optimal hyperparameter was achieved by using GridSearch with 5-fold cross-validation from the scikit-learn library. Model performance was externally assessed via the receiver operating characteristic (ROC) and decision curve analysis (DCA). Explainable machine learning was performed using the Python SHapley Additive exPlanation (SHAP) package and Seaborn library, which allow the calculation of marginal contributory SHAP value. Results: 637 patients (30.2%) developed CSA-AKI within seven days after surgery. In the external validation, the RF classifier exhibited the best performance among the six machine learning techniques, as shown by the ROC curve and DCA, while the traditional APPROACH risk score showed a relatively poor performance. Further analysis found no specific causative factor contributing to the development of CSA-AKI; rather, the development of CSA-AKI appeared to be a complex process resulting from a complex interplay of multiple risk factors. The SHAP summary plot illustrated the positive or negative contribution of RF-top 20 variables and extrapolated risk of developing CSA-AKI at individual levels. The Seaborn library showed the effect of each single feature on the model output of the RF prediction. Conclusions: Efficient machine learning approaches were successfully established to predict patients with a high probability of developing acute kidney injury after cardiac surgery. These findings are expected to help clinicians to optimize treatment strategies and minimize postoperative complications. Clinical Trial Registration: The study protocol was registered at the ClinicalTrials Registration System (https://www.clinicaltrials.gov/, #NCT04966598) on July 26, 2021.

Application of Machine Learning Algorithms to Predict New-Onset Postoperative Atrial Fibrillation and Identify Risk Factors Following Isolated Valve Surgery.

BACKGROUND: New-onset postoperative atrial fibrillation (POAF) is the most common complication after valvular surgery, but its etiology and risk factors are incompletely understood. This study investigates the benefits of machine learning methods in risk prediction and in identifying relative perioperative variables for POAF after valve surgery. METHODS: This retrospective study involved 847 patients, who underwent isolated valve surgery from January 2018 to September 2021 in our institution. We used machine learning algorithms to predict new-onset postoperative atrial fibrillation and to select relatively important variables from a set of 123 preoperative characteristics and intraoperative information. RESULTS: The support vector machine (SVM) model demonstrated the best area under the receiver operating characteristic (AUC) value of 0.786, followed by logistic regression (AUC = 0.745) and the Complement Naive Bayes (CNB) model (AUC = 0.672). Left atrium diameter, age, estimated glomerular filtration rate (eGFR), duration of cardiopulmonary bypass, New York Heart Association (NYHA) class III-IV, and preoperative hemoglobin were high-ranked variables. CONCLUSIONS: Risk models based on machine learning algorithms may be superior to traditional models, which were primarily based on logistic algorithms to predict the occurrence of POAF after valve surgery. Further prospective multicenter studies are needed to confirm the performance of SVM in predicting POAF.

Alleviation of cadmium-induced oxidative stress by trehalose via inhibiting the Nrf2-Keap1 signaling pathway in primary rat proximal tubular cells.

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor that regulates a cluster of oxidative stress-inducible genes in cells. Here, we aimed to investigate whether trehalose (Tre) protects primary rat proximal tubular (rPT) cells against cadmium (Cd)-induced oxidative stress via Nrf2 antioxidant pathway. Data showed that Tre treatment inhibited Nrf2 nuclear translocation and restored the decline in Kelch-like ECH-associated protein 1 (Keap1) protein level in Cd-exposed rPT cells. Moreover, Cd-activated Nrf2 target genes, including phase II detoxifying enzymes, that is, NAD(P)H quinone oxidoreductase 1 and heme oxygenase-1, direct antioxidant proteins, that is, glutathione peroxidase, superoxide dismutase, catalase, and glutathione biosynthesis-related proteins, that is, glutamatecysteine ligase catalytic subunit, glutamate cysteine ligase modifier subunit, and glutathione reductase, were all downregulated by co-treatment with Tre. Collectively, these findings demonstrate that Tre treatment alleviates Cd-induced oxidative stress in rPT cells by inhibiting the Nrf2-Keap1 signaling pathway.

Citrus-derived flavanones as neuraminidase inhibitors: In vitro and in silico study.

Neuraminidase (NA) has been well-studied as a therapeutic target for Influenza. However, resistance to the influenza virus has been observed recently. Out of special interest in the utilization of dietary antivirals from citrus, in vitro inhibition activity against NA and in silico studies including molecular docking, molecular dynamic simulation, and a predictive ADMET study, were performed on five citrus-derived flavanones. Encouragingly, citrus-derived flavanones displayed comparable or even more potent in vitro inhibitory activity than oseltamivir carboxylate against NA. Orange peel extract exhibited higher activity than hesperidin. Among the tested compounds, neohesperidin, forming strong hydrogen-bonding interactions with key arginine residues, exhibited the most effective inhibitory activity against NAs from C. perfringens, consistent with the results of molecular dynamics simulations. Although the molecular docking results were inconsistent with the in vitro activity, the binding energy was identical against the wild-type and mutant, suggesting a lower likelihood of developing drug resistance. Moreover, predictive ADMET studies showed favorable pharmacokinetic properties for the tested compounds. Overall, citrus fruit peel emerges as a promising dietary supplement for prevention and treatment of influenza. These findings elucidate the impact of flavanones on NA activity, and the analysis of their binding modes provides valuable insights into the mechanism of NA inhibition.

Growth Reduction of Vibrionaceae and Microflora Diversity in Ice-Stored Pacific White Shrimp (Penaeus vannamei) Treated with a Low-Frequency Electric Field.

A novel storage technique that combines the low-frequency electric field (LFEF) and ice temperature was used to extend the shelf life of Pacific white shrimp (Penaeus vannamei). The study investigated the effect of LFEF treatment on the quality and microbial composition of Penaeus vannamei during storage at ice temperature. The results showed that the LFEF treatment significantly extended the shelf life of shrimp during storage at ice temperature. The total volatile base nitrogen (TVB-N) and pH of samples increased over time, while the total viable count (TVC) showed a trend of first decreasing and then increasing. Obviously, shrimp samples treated with LFEF had a lower pH, TVB-N and TVC values than the untreated samples (p < 0.05) at the middle and late stages of storage. LFEF treatment increased the diversity and altered the composition of the microbial communities in Penaeus vannamei. Additionally, the treatment led to a decrease in the relative abundance of dominant spoilage bacteria, including Aliivibrio, Photobacterium and Moritella, in Penaeus vannamei stored at ice temperature for 11 days. Furthermore, correlation analysis indicated that TVB-N and pH had a significant and positive correlation with Pseudoalteromonas, suggesting that Pseudoalteromonas had a greater impact on shrimp quality. This study supports the practical application of accelerated low-frequency electric field-assisted shrimp preservation as an effective means of maintaining shrimp meat quality.

Role of long non-coding RNA DLY6E in regulating TMUV infection.

Long non-coding RNA (lncRNA) is a type of RNA with a length greater than 200 nt and lacking coding ability. In recent years, a considerable number of lncRNAs have been found to have important functions. The lncRNA plays an important role in growth and development, body metabolism, immune function, and regulation of viral replication. A lncRNA, MSTRG8505.2, was screened and named lncRNA DLY6E, which was a new duck-derived lncRNA. The lncRNADLY6E in this study has a complex secondary structure, specifically distributed in the heart, liver and other organs. The expression of lncRNA DLY6E was significantly up-regulated after TMUV infection, which was time-dependent and non-dose-dependent. Overexpression of three structural proteins and seven non-structural proteins of TMUV in DEF cells showed no significant difference in the expression of lncRNADLY6E. Meanwhile, using lipopolysaccharides (LPS) and poly (I:C) to stimulate DEF cells, the results showed that the induced expression of lncRNA DLY6E was associated with the dsRNA-related TLR3/RIG-I/MDA5 pathway rather than the LPS activated signaling pathway. To further explore the function of lncRNA DLY6E, an eukaryotic expression vector was constructed. Overexpression of lncRNA DLY6E in DEF cells can increase the replication of TMUV. After overexpression of lncRNADLY6E, the transcriptional level of its target gene LY6E was detected, and the results showed that lncRNADLY6E did not act through its target gene. Overexpression of lncRNA DLY6E significantly inhibited the mRNA levels of OAS, Mx and PKR, suggesting that lncRNA DLY6E may promote the virus by inhibiting the transcription of antiviral proteins in innate immunity. This phenomenon provides new ideas for the prevention and control of TMUV, which is worth further thinking and exploration.

Pathogenicity of duck circovirus 1 in experimentally infected specific pathogen-free ducks.

Ducks infected with duck circovirus (DuCV) show symptoms such as feather loss, growth retardation and low body weight in the flock. The virus induces immunosuppression and increases the prevalence of infection with other pathogens. However, most studies on duck circovirus were focused on coinfection, and fewer studies had been conducted on the pathogenicity of duck circovirus alone. The aim of the present study was to investigate the pathogenesis of DuCV-1 in experimentally infected specific pathogen-free ducks. In this study, we sequenced the whole genome of a strain of duck circovirus and identified the virus genotype as DuCV-1b. This strain of duck circovirus was named SDLH(OR567883). Animal pathogenicity experiments were then conducted, wherein specific pathogen-free ducks were infected by mucosal injection and abdominal injection. Infected ducks were sampled for 4 consecutive weeks after infection and showed symptoms of dwarfism. We further examined the replication of DuCV-1 in the ducks. The highest virus titers in the 2 infection groups were found in the liver and spleen, with different results for the different routes of infection. Pathological sections of duck organs were made and it was found that organs such as the liver and spleen were damaged by DuCV-1. In conclusion, our experimental results indicate that DuCV-1 can infect ducks individually and cause widespread organ damage in infected ducks.

Short communication: possible mechanism for inhibiting the formation of polymers originated from 5-hydroxymethyl-2-furaldehyde by sulfite groups in the dairy thermal process.

5-Hydroxymethyl-2-furaldehyde can undergo polymerization to form high-molecular weight molecules via the Maillard reaction during dairy thermal treatment. In this study, the effect of sulfite group on polymer formation, especially in inhibiting the formation of high-molecular weight polymers has been described. Results showed that the sulfite group significantly inhibited the increase of polymer molecular weight via prevention of the polymerization of 5-hydroxymethyl-2-furaldehyde. The formation of an intermolecular dimer based on the glucose molecule through Schiff base cyclization can lead to a competitive reaction with 1,2-enolization to reduce 5-hydroxymethyl-2-furaldehyde formation, which might be another factor in reducing the formation of high-molecular weight polymers.

Fractionation of depectinated sugar beet pulp into cellulose, hemicellulose, and lignin with NaOH/urea/H2O and ionic liquid.

This study proposes a novel and feasible dissolution and fractionation method of depectinated sugar beet pulp (SBP) in NaOH/Urea/H2O, ionic liquid (IL) and alkaline treatment processes. Interestingly, the complicated structure of SBP can be treated with 30 % H2SO4 to increase the dissolution rate. Scanning electron microscope (SEM) analysis confirmed that the appearance of cellulose and hemicellulose obtained by two methods were different. At the same time, two lignin fractions showed irregular high-density clusters, which were composed of a large number of submicron particles. The crystal structure of two cellulose fractions changed from cellulose I to cellulose II. The thermal stability of cellulose and lignin obtained by ionic liquid was slightly better than that obtained by NaOH/urea/H2O. Results of Fourier transform infrared (FTIR) and 13C NMR showed that the chemical structures of SBP cellulose, hemicellulose and lignin regenerated from NaOH/urea/H2O and ionic liquid were similar.

Development and biochemical characteristics of a monoclonal antibody against prM protein of Tembusu virus.

Tembusu virus (TMUV), a pathogenic member of the Flavivirus family, is an infectious diseases that seriously jeopardize duck health in 2010 in China. TMUV disease causes significant economic losses to the duck industry. This study aimed to prepare monoclonal antibodies against TMUV prM protein and to identify their epitopes. The 501bp prM gene was amplified to the pET-32a prokaryotic expression vector and expressed as a recombinant protein of size 38 KD in Escherichia coli. The purified recombinant proteins were inoculated into BALB/c mice to generate splenic lymphocytes capable of secreting anti-prM antibodies, and hybridoma cells were obtained after fusion with SP2/0 cells. A new hybridoma cell line named B27, which stably secreted IgG1-antibody against TMUV prM with high antibody titers up to 1:1:3,276,800 was screened. This monoclonal antibody (mAb) is well specific and can be used for ELISA/Western-blot (WB)/indirect fluorescence assay (IFA) etc. The mAb B27 has poor neutralization ability and concentration dependence, with a maximum neutralization degree of 23.87% at antibody dilution 10-6. Next, we truncated prM gene and expressed the truncated protein to screen antigen epitopes. The mAb's linear antigen epitope of the TMUV prM protein was first identified and was accurate to 6 consecutive amino acids 59GYEPED64, which located in the pr protein. Bioinformatic analysis showed that this antigenic epitope was located on the surface of the antigen, which was conducive to the direct contact of antigen antibody and conformed to the properties of antigenic epitopes. In addition, its 6 amino acids are highly homologous among 27 published TMUV strains, indicating that its epitope is stable. This study will help to further understand the protein structure and the function of prM, and lay the foundation for establishing specific prM detection methods and the mechanistic study of TMUV prM protein.

Development of a HPLC-UV Method for the Separation and Quantification of Hesperidin, Neohesperidin, Neohesperidin Dihydrochalcone and Hesperetin.

An analysis method was developed for the separation and quantification of hesperidin, neohesperidin, neohesperidin dihydrochalcone and hesperetin by using HPLC-UV. Single factor experiments and Box-Behnken Designs were used to optimize separation of four flavonoids, in which a gradient elution method was adopted with 99% acetonitrile and 0.1% formic acid as mobile phases at a flow rate of 0.9 mL/min. A C18 column was used with a column temperature of 35 °C. LODs and LOQs were below 0.84 µg/mL and 2.84 µg/mL, respectively. Linearity with good correlation coefficients (r > 0.99, n = 5) was attained, recovery rate of four flavonoids ranged from 88% to 130%, the RSD indicating results precision for analyzing hesperidin, neohesperidin, neohesperidin dihydrochalcone and hesperetin ranged from 1.2% to 4.6%. Finally, the present method could be successfully applied to identify and quantify hesperidin, neohesperidin and hesperetin in Fructus Aurantii Immaturus and Pericarpium Citri Reticulatae.

Prediction of new onset postoperative atrial fibrillation using a simple Nomogram.

BACKGROUND: New onset postoperative atrial fibrillation (POAF) is the most common complication of cardiac surgery, with an incidence ranging from 15 to 50%. This study aimed to develop a new nomogram to predict POAF using preoperative and intraoperative risk factors. METHODS: We retrospectively analyzed the data of 2108 consecutive adult patients (> 18 years old) who underwent cardiac surgery at our medical institution. The types of surgery included isolated coronary artery bypass grafting, valve surgery, combined valve and coronary artery bypass grafting (CABG), or aortic surgery. Logistic regression or machine learning methods were applied to predict POAF incidence from a subset of 123 parameters. We also developed a simple nomogram based on the strength of the results and compared its predictive ability with that of the CHA2DS2-VASc and POAF scores currently used in clinical practice. RESULTS: POAF was observed in 414 hospitalized patients. Logistic regression provided the highest area under the receiver operating characteristic curve (ROC) in the validation cohort. A simple bedside tool comprising three variables (age, left atrial diameter, and surgery type) was established, which had a discriminative ability with a ROC of 0.726 (95% CI 0.693-0.759) and 0.727 (95% CI 0.676-0.778) in derivation and validation subsets respectively. The calibration curve of the new model was relatively well-fit (p = 0.502). CONCLUSIONS: Logistic regression performed better than machine learning in predicting POAF. We developed a nomogram that may assist clinicians in identifying individuals who are prone to POAF.

Current Advances in the Regulatory Effects of Bioactive Compounds from Dietary Resources on Nonalcoholic Fatty Liver Disease: Role of Autophagy.

Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease characterized by lipid metabolic disorder primarily due to sedentary lifestyles and excessive food consumption. However, there are currently no approved and effective drugs available to treat NAFLD. In recent years, research has shown that dietary bioactive compounds, such as polysaccharides, polyphenols, flavones, and alkaloids, have the potential to improve NAFLD by regulating autophagy. However, there is no up-to-date review of research progress in this field. This review aims to systematically summarize and discuss the regulatory effects and molecular mechanisms of dietary bioactive compounds on NAFLD through the modulation of autophagy. The existing research has demonstrated that some dietary bioactive compounds can effectively improve various aspects of NAFLD progression, such as lipid metabolism, insulin resistance (IR), endoplasmic reticulum (ER) stress, oxidative stress, mitochondrial homeostasis, and inflammation. Molecular mechanism studies have revealed that they exert their beneficial effects on NAFLD through autophagy-mediated signaling pathways, predominantly involving transcription factor EB (TFEB), mammalian target of rapamycin (mTOR), adenosine monophosphate-activated protein kinase (AMPK), peroxisome proliferator-activated receptors (PPARs), SIRT, and PTEN-induced kinase 1 (PINK1)/parkin. Furthermore, the challenges and prospects of current research in this field are highlighted. Overall, this review provides valuable insights into the potential treatment of NAFLD using dietary bioactive compounds that can modulate autophagy.

Effects of glycation with chitooligosaccharide on digestion and fermentation processes of lactoferrin in vitro.

This study aimed to investigate the digestion and fermentation processes of lactoferrin (LF) glycated with chitooligosaccharide (COS) under a controlled Maillard reaction, utilizing the in vitro digestion and fermentation model, and to compare the results of these processes to LF undertaken without glycation. After gastrointestinal digestion, the products of the LF-COS conjugate were found to have more fragments with lower molecular weight than LF, and the antioxidant capabilities (via ABTS and ORAC assay) of the LF-COS conjugate digesta also increased. In addition, the undigested fractions could be further fermented by the intestinal microbiota. Compared with LF, more short-chain fatty acids (SCFAs) were generated (from 2397.40 to 2623.10 µg/g), and more species of microbiota (from 451.78 to 568.10) were observed in LF-COS conjugate treatment. Furthermore, the relative abundance of Bacteroides and Faecalibacterium that could utilize carbohydrates and metabolic intermediates to produce SCFAs also increased in LF-COS conjugate than that of LF. Our results demonstrated that glycation with COS under the controlled wet-heat treatment Maillard reaction could modify the digestion of LF and have a potentially positive influence on the intestinal microbiota community.

28-day repeated dose oral toxicity of human copper-zinc superoxide dismutase from recombinant Pichia pastori in rats.

Human copper/zinc superoxide dismutase from recombinant Pichia pastori (RH-Cu/Zn-SOD) was orally administered, via gavage, to Sprague-Dawley rats at 500, 1,000, and 2,000 mg/kg body weight/day for 28 days. During the 28-day period, animals were examined for evidence of toxicity; there were no deaths, and in-life physical signs were normal. On day 29, the animals were exsanguinated, examined for gross pathology, and tissues were preserved for histopathology. Although statistical differences were noted in some hematology and clinical chemistry, they were of questionable biological significance. The results of the 28-day oral administration demonstrated a lack of toxicity of RH-Cu/Zn-SOD in rats. There were no treatment-related, toxicologically relevant changes in clinical signs, growth, food consumption, hematology, clinical chemistry, organ weights, or pathology. The no observed adverse effect level was greater than 2,000 mg/kg/day for RH-Cu/Zn-SOD in rats.

Antioxidant and antimicrobial activities of essential oil and extracts of Saurauia lantsangensis hu root.

Antioxidant and antimicrobial activities of the essential oil and n-hexane (HEE), chloroform (CHE), ethyl acetate (EAE), and methanol (MEE) extracts, respectively, from the root of Saurauia lantsangensis Hu were investigated. The GC-MS analysis revealed 39 compounds representing 96.41% of the oil containing T-muurolol (13.85%), acetophenone (7.46%), alpha-cadinol (6.26%), methyl palmitate (5.36%), n-hexadecanoic acid (4.31%), torreyol (3.69%), and isospathulenol (3.48%) as major components. Antioxidant activities determined by three various testing systems, i.e., DPPH radical scavenging, superoxide anion radical scavenging, and reducing power assay, increased in the order: HEE < CHE < oil < MEE < EAE. CHE, EAE, MEE and oil exhibited a promising antimicrobial effect determined as the diameter of zones of inhibition (13.3-16.2, 16.5-20.4, 13.5-16.6, and 16.5-22.7 mm), respectively, along with their respective MIC values (500-1000, 125-500, 250-500, and 250-500 microg/ml) against Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli), Gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus), and a yeast (Hansenula anomala).

Poly[diaqua-(µ(5)-1H-imidazole-4,5-di-carboxyl-ato)(µ(4)-1H-imidazole-4,5-di-carboxyl-ato)tris-ilver(I)ytterbium(III)].

The asymmetric unit of the title compound, [Ag(3)Yb(C(5)HN(2)O(4))(2)(H(2)O)(2)](n), contains three Ag(I) ions, one Yb(III) ion, two imidazole-4,5-dicarboxyl-ate ligands and two coordinating water mol-ecules. The Yb(III) atom is eight-coordinated, in a bicapped trigonal prismatic coordination geometry, by six O atoms from three imidazole-4,5-dicarboxyl-ate ligands and two coordinating water mol-ecules. The two-coordinated Ag(I) ions exhibit three types of coordination environments. One Ag(I) atom is bonded to two N atoms from two different imidazole-4,5-dicarboxyl-ate ligands. The other two Ag(I) atoms are each coordinated by one O atom and one N atom from two different imidazole-4,5-dicarboxyl-ate ligands. These metal coordination units are connected by bridging imidazole-4,5-dicarboxyl-ate ligands, generating a two-dimensional heterometallic layer. These layers are stacked along the a axis via O-H⋯O hydrogen-bonding inter-actions to generate a three-dimensional framework.

Anilinium 3,4-dihy-droxy-benzoate.

The asymmetric unit of the title salt, C(6)H(8)N(+)·C(7)H(5)O(4) (-), contains two anilinium cations and two 3,4-dihy-droxy-benzoate anions. An intra-moleculer O-H⋯O hydrogen bond occurs in each anion. In the crystal, O-H⋯O and N-H⋯O hydrogen bonds link the cations and anions into a three-dimensional array. The structure is further consolidated by weak C-H⋯O inter-actions.