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AbstractThe Fabaceae family contains a shrub tree called Vachellia flava (Syn.: Acacia ehrenbergiana), and considering its ethnopharmacological uses, it is recognized as a significant traditional medicinal herb. We herein aim to evaluate the biological potential of V. flava crude extract, including antioxidant, antimicrobial, antiparasite, and toxicity against normal cells. Furthermore, the chemical composition of the crude extract of V. flava was investigated. Antimicrobial results showed that the crude extract possessed significant activity against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans at various concentrations. The plant extracts also exhibited high antiparasite activity against Giardia intestinalis and scavenged DPPH• free radicals. An in vitro MTT assay showed no toxicity in normal cells. At the same time, by assaying the in vivo acute toxicity in rats, slight changes in various rat parameters were detected. GC-MS analysis of V. flava identified a phenolic compound as the most abundant constituent, pyrogallol (42.79%), followed by a sugar (4-O-methylmannose; 17.96%), a diterpenoid (1S,3E,4S,5R,7E,11E)-cembra-2,7,11-trien-4,5-diol; 14.49%), and a fatty acid (n-hexadecanoic acid; 12.87%). Considering all the prominent bioactivities, the plant serves as an excellent example to be considered for further phytochemical and pharmacological investigation. [ABSTRACT FROM AUTHOR]

Many phenolics are known to possess allelopathic activity, but the allelopathic effect of pyrogallol has not been previously reported. Here, the present experiment was conducted to investigate the effects of commercially obtained pyrogallol at different concentrations on the seed germination and seedling growth of L. perenne. The results showed that (1) Pyrogallol treatment inhibited L. perenne seed germination, as evidenced by a decrease in the final germination rate and a delay in germination peaks. (2) Pyrogallol treatment reduced L. perenne plumule length, radicle length, fine root length, and fine root surface area, higher pyrogallol concentrations reduced the proportion of fine roots. (3) Higher concentrations (2.00 g/L) of pyrogallol resulted in decreased protein content and increased membrane lipid peroxidation. (4) Spraying pyrogallol inhibited the growth of L. perenne seedlings, as manifested by a decrease in plant height and biomass. Overall, our findings indicate that pyrogallol is one of the allelochemicals present in aqueous extracts of K. integrifoliola leaves that inhibits the seed germination and seedling growth of L. perenne. [ABSTRACT FROM AUTHOR]

Abstract Sulfonamide derivatives as semiconductor materials for organic optoelectronic devices, including photovoltaic (PV), have received considerable interest. In the present work, the synthesis of novel pyrogallol-sulfonamide derivatives based on a molecular hybridization approach yielded N-((4-((2,3,4-trihydroxyphenyl)diazenyl)phenyl)sulfonyl)acetamide (N-DPSA). The techniques of spectroscopy, Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H NMR), and mass spectrum were utilized to identify the structural composition of the synthesized N-DPSA. The new N-DPSA was investigated by Hall-effect measurement to prove the positive charge carrier (hole mobility) with mobility and conductivity of 2.39 × 103 cm2/Vs and 1.76 × 10–1 1/Ω cm, respectively. Consequently, N-DPSA could be proposed as a strong candidate as a p-type semiconductor (hole transport layer (HTL)). The optical energy gap was computed at 2.03 eV, indicating the direct optical transition nature of N-DPSA. The elaborated molecular semiconductor's thermal features, molecular modelling, and electronic energy levels were also investigated. The new N-DPSA at various concentrations provided easy synthesis, cheap cost, high performance, and a straightforward design approach for a possible HTL in effective perovskite solar cells (PSCs). A PCE of 7.3% is shown for the N-DPSA-based PSC at its optimal concentration.

Sulfonamide derivatives as semiconductor materials for organic optoelectronic devices, including photovoltaic (PV), have received considerable interest. In the present work, the synthesis of novel pyrogallol-sulfonamide derivatives based on a molecular hybridization approach yielded N-((4-((2,3,4-trihydroxyphenyl)diazenyl)phenyl)sulfonyl)acetamide (N-DPSA). The techniques of spectroscopy, Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H NMR), and mass spectrum were utilized to identify the structural composition of the synthesized N-DPSA. The new N-DPSA was investigated by Hall-effect measurement to prove the positive charge carrier (hole mobility) with mobility and conductivity of 2.39 × 103 cm2/Vs and 1.76 × 10–1 1/Ω cm, respectively. Consequently, N-DPSA could be proposed as a strong candidate as a p-type semiconductor (hole transport layer (HTL)). The optical energy gap was computed at 2.03 eV, indicating the direct optical transition nature of N-DPSA. The elaborated molecular semiconductor's thermal features, molecular modelling, and electronic energy levels were also investigated. The new N-DPSA at various concentrations provided easy synthesis, cheap cost, high performance, and a straightforward design approach for a possible HTL in effective perovskite solar cells (PSCs). A PCE of 7.3% is shown for the N-DPSA-based PSC at its optimal concentration. [ABSTRACT FROM AUTHOR]

Background: Pyrogallol, a bioactive compound derived from natural sources, is the focus of this study, aiming to investigate its anti-cancer properties against A549 lung cancer cells and uncover the underlying mechanisms. Purpose: This study seeks to elucidate the therapeutic potential of pyrogallol as a novel anti-cancer agent for NSCLC by targeting aerobic glycolysis and signal transducer and activator of transcription 2 (STAT2) signaling pathway. Background: Pyrogallol, a bioactive compound derived from natural sources, is the focus of this study, aiming to investigate its anti-cancer properties against A549 lung cancer cells and uncover the underlying mechanisms. Materials and Methods: A range of pyrogallol doses was administered to A549 cells, followed by a comprehensive analysis utilizing bioinformatic tools like Gene Expression Omnibus (GEO), GEO2R, WebGestalt, and the Search Tool for Interactions of Chemicals database. Assessments of cytotoxicity were conducted using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and trypan blue assays post-treatment of A549 cells with pyrogallol. Cell cycle progression and cell death were evaluated via flow cytometry using Annexin V-fluorescein isothiocyanates/propidium iodide double staining. Network analysis helped identify pertinent signaling pathways, while RT-PCR validated mRNA expression changes in A549 cells. Auto dock docking studies were employed to gauge the binding affinity of pyrogallol with targets associated with the STAT2-mediated pathway. Results: Pyrogallol notably impeded the progression of A549 cells by prompting cell cycle arrest in the G0/G1 phase and fostering apoptosis. Network analysis highlighted its role in regulating metabolism, apoptosis, and STAT2 targets linked to lung tumorigenesis. RT-PCR validation affirmed the downregulation of genes associated with cell cycle and apoptosis targets. Furthermore, docking studies indicated a robust binding affinity between pyrogallol and the signaling targets within the STAT2 pathway. Pyrogallol displays the potential to halt the growth of lung cancer cells, indicating its promise as a viable treatment for this condition. Conclusion: These discoveries emphasize the need for additional research and clinical studies to fully harness its therapeutic benefits for lung cancer treatment. [ABSTRACT FROM AUTHOR]

This study aimed to explore the inhibitory effect of pyrogallol on AGE formation in the bovine serum albumin (BSA)/glucose system for 21 days at 37 °C. The AGEs formation was measured in terms of Amadori products, total AGEs, argpyrimidine, and pentosidine. Molecular docking was used to investigate the interaction between pyrogallol and BSA. According to the results, in the presence of pyrogallol, the formation of pentosidine and argpyrimidine AGEs decreased. The molecular interaction studies demonstrated that pyrogallol has a high affinity towards arginine residues of albumin. Finally, results proved pyrogallol is a vigorous antiglycation compound and fruitful for AGE inhibition. [ABSTRACT FROM AUTHOR]

The rising incidence of extensively drug-resistant (XDR) Klebsiella pneumoniae, including carbapenem- and colistin-resistant strains, leads to the limitation of available effective antibiotics. Miang, known as chewing tea, is produced from Camellia sinensis var. assamica or Assam tea leaves fermentation. Previous studies revealed that the extract of Miang contains various phenolic and flavonoid compounds with numerous biological activities including antibacterial activity. However, the antibacterial activity of Miang against XDR bacteria especially colistin-resistant strains had not been investigated. In this study, the compositions of phenolic and flavonoid compounds in fresh, steamed, and fermented Assam tea leaves were examined by HPLC, and their antibacterial activities were evaluated by the determination of the MIC and MBC. Pyrogallol was detected only in the extract from Miang and showed the highest activities with an MIC of 0.25 mg/mL and an MBC of 0.25–0.5 mg/mL against methicillin-susceptible Staphylococcus aureus, methicillin-resistant S. aureus, Escherichia coli ATCC 25922, colistin-resistant E. coli, and colistin-resistant K. pneumoniae. The effects on morphology and proteomic changes in K. pneumoniae NH54 treated with Miang extract were characterized by SEM and label-free quantitative shotgun proteomics analysis. The results revealed that Miang extract caused the decrease in bacterial cell wall integrity and cell lysis. The up- and downregulated expression with approximately a 2 to >5-fold change in proteins involved in peptidoglycan synthesis and outer membrane, carbohydrate, and amino acid metabolism were identified. These findings suggested that Miang containing pyrogallol and other secondary metabolites from fermentation has potential as an alternative candidate with an antibacterial agent or natural active pharmaceutical ingredient against XDR bacteria including colistin-resistant bacteria. [ABSTRACT FROM AUTHOR]

This research demonstrated and analyzed the complexation capabilities of the dipodal chelator N¹,N³-bis(2-((E)-2,3,4-trihydroxybenzylidene)amino)ethyl)malonamide (MEP) with heavy metal ions, viz., Al3+, Fe3+, and Cr3+, by engaging potentiometric and spectrophotometric methods. The whole experiment was carried out in a pH-dependent manner in a highly aqueous medium with a pH range of 2 to 11. The potentiometric and spectrophotometric results suggest the highest binding affinity of the chelator MEP with Al3+ metal ions among all three metal ions under study, with a stability constant value of log β = 27.13. [ABSTRACT FROM AUTHOR]

Nanoencapsulation technology enables the efficient delivery of natural bioactive compounds, enhancing stability and controlled release to improve bioavailability and therapeutic efficacy. Pyrogallol, a natural polyphenolic compound, has shown promising anticancer activities against various cancer cell lines. The purpose of this study was to synthesize and characterize nanocapsule-encapsulated pyrogallol (Na-Pyr) and investigate its anticancer potential, apoptotic signaling, and anti-metastatic properties. The process involved synthesizing the nanocapsules using the sol–gel method and evaluating their physical and chemical properties using various techniques. The MTT assay was used to test Na-Pyr’s cytotoxicity against various cancer cell lines, including ovarian cancer (A2780), human colorectal adenocarcinoma (HT-29), and pancreatic cancer (ASPC-1), with Huvec serving as the normal cell line. DAPI staining, real-time PCR, and flow cytometry were performed to examine apoptosis induction and cell cycle arrest. The results obtained from dynamic light scattering (DLS) manifested that Na-Pyr had a size of 176.4 ± 7.26 nm, an average zeta potential of about 42.1 ± 2.01 mV, and a polydispersity (PDI) index of 0.174 ± 0.02. Electron microscopy images exhibited a smooth surface and spherical shape, indicating material compatibility. Na-Pyr exhibited higher anticancer potential against ovarian cancer cells than HT-29 and ASPC-1 cancer cell lines with an IC50 value of 23.5 ± 0.95 μg/mL. Na-Pyr significantly modulates the Bax/Bcl2 ratio and activates the MMP9 pathway-mediated apoptosis. Flow cytometry analysis supported these findings, revealing increased percentages of necrotic, early apoptotic, and late apoptotic populations upon exposure to Na-Pyr. In conclusion, the study highlights the promising anticancer potential of Na-Pyr and its potential as an effective treatment strategy.

Pyrogallol, a natural polyphenol compound (1,2,3‐trihydroxybenzene), has shown efficacy in the therapeutic treatment of disorders associated with inflammation. Nevertheless, the mechanisms underlying the protective properties of pyrogallol against influenza A virus infection are not yet established. We established in this study that pyrogallol effectively alleviated H1N1 influenza A virus‐induced lung injury and reduced mortality. Treatment with pyrogallol was found to promote the expression and nuclear translocation of nuclear factor erythroid‐2‐related factor 2 (Nrf2) and peroxisome proliferator‐activated receptor gamma (PPAR‐γ). Notably, the activation of Nrf2 by pyrogallol was involved in elevating the expression of PPAR‐γ, both of which act synergistically to enhance heme oxygenase‐1 (HO‐1) synthesis. Blocking HO‐1 by zinc protoporphyrin (ZnPP) reduced the suppressive impact of pyrogallol on H1N1 virus‐mediated aberrant retinoic acid‐inducible gene‐I‐nuclear factor kappa B (RIG‐I–NF‐κB) signaling, which thus abolished the dampening effects of pyrogallol on excessive proinflammatory mediators and cell death (including apoptosis, necrosis, and ferroptosis). Furthermore, the HO‐1‐independent inactivation of janus kinase 1/signal transducers and activators of transcription (JAK1/STATs) and the HO‐1‐dependent RIG‐I‐augmented STAT1/2 activation were both abrogated by pyrogallol, resulting in suppression of the enhanced transcriptional activity of interferon‐stimulated gene factor 3 (ISGF3) complexes, thus prominently inhibiting the amplification of the H1N1 virus‐induced proinflammatory reaction and apoptosis in interferon‐beta (IFN‐β)‐sensitized cells. The study provides evidence that pyrogallol alleviates excessive proinflammatory responses and abnormal cell death via HO‐1 induction, suggesting it could be a potential agent for treating influenza. [ABSTRACT FROM AUTHOR]

Mentha arvensis L. var. 'kosi', occasionally recognized as corn mint or field mint, belongs to the Lamiaceae family and is widely grown in temperate climates throughout Europe, western and central Asia, as well as North America for its medicinal significance (Aflatuni et al, 2005). The essential oil extracted from the mint plant reveals a rich assortment of secondary metabolites. Among these compounds are menthol, menthone, menthyl acetate, neomenthol, á-pinene, â-pinene, piperitone, limonene, tannins, and flavonoids. The recognition and analysis of these constituents contribute to a thorough understanding of the intricate chemical composition inherent in mint plant essential oil (Akram et al, 2011). The plant has long been utilized in Indian medicine to alleviate stomach problems, fevers, and headaches. The influence of phenolic compounds on antimicrobial, antibacterial and antioxidant activities, germination and early development of herbaceous woodland plants, and seed germination has sparked considerable attention. Menthol, obtained from the essential oil of the mint plant, is credited with therapeutic properties that effectively combat skin allergies. Additionally, it demonstrates diuretic properties and serves as an antiseptic and carminative agent. The authors observed that the stimulating effects of salicylic acid, methyl jasmonate and similar phenolic compounds can be used to increase the content present in the essential oil and medicinal and pharmacological values of the plants of the Lamiaceae family. This idea led us to try the other phenolic compounds' foliar application to various species of mint with an expectation to increase the quality of these plants. The present study had the goal to evaluate if the exogenous foliar application of different phenolic compounds (phenol, catechol, pyrogallol, picric acid and salicylic acid) at concentration of 1.0 mM can optimize the physiological, biochemical activities and essential oil production in 120-day-old mint plants. Growth and physiological, biochemical, and total essential oil content assessments inclusive of menthol, menthone, menthyl acetate indicated that 1.0 mM concentration of pyrogallol and salicylic acid were most potent at eliciting a general stimulation of mint metabolism. Overall, the findings demonstrate that salicylic acid and pyrogallol stimulate mint physiology and open up new avenues for biotechnological application on additional plant species with agronomic promise. [ABSTRACT FROM AUTHOR]

Heavy metal ions are a major concern due to their ability to harm both people and the environment. Heavy metal ion toxicity has been shown to be significantly reduced by schiff base biomimetic ligands. We have investigated the thermodynamic and stability parameters for Schiff base ligand MEP-trivalent metal ions (Al3+, Cr3+ and Fe3+) complexes based on pyrogallol using DFT and TD-DFT methodologies. In order to propose the function of these metal-ligand complexes in various biological, sensing, and catalytic applications, we have also conducted conceptual density functional theory analysis. We have given the capabilities of MEP-Al3+, MEP-Cr3+, and MEP-Fe3+ complexes to a wide range of industrial and research-based applications, with the primary motto of "Waste to riches" as our guiding principle. TD-DFT, conceptual DFT, and DFT were used in our joint investigation, which led to this conclusion. [ABSTRACT FROM AUTHOR]

Pyrogallol (1,2,3‐trihydroxybenzene), a polyphenolic natural compound, has attracted considerable attention with regard to its potential anticancer activity. However, further study is needed to elucidate the underlying mechanism related to the antiNSCLC activity of pyrogallol and provide a comprehensive theoretical basis for better clinical utilization of pyrogallol. Our current study aims to investigate the effects and potential underlying mechanisms of pyrogallol on the inhibition of NSCLC growth. Our results showed that pyrogallol treatment induced cell cycle arrest at the G2/M phase and apoptosis in two different NSCLC cell lines. Mechanistically, we found that the induction of cell cycle arrest in NSCLC cells at the G2/M phase by pyrogallol was due to the upregulation of p21 in a p53‐dependent manner. And blockade of p53 and p21 effectively abolished the cell cycle arrest at the G2/M phase. Meanwhile, p53 inhibition has been found to abrogate the pyrogallol‐induced apoptosis of the two NSCLC cells. Moreover, we revealed that the inhibitory effects of pyrogallol on β‐catenin signaling resulted from autophagy initiation depending on p53 activation, accompanied by an increase in p62/SQSTM1 expression, thus p62 subsequently interacting with ubiquitinated β‐catenin and facilitating autophagic destruction of β‐catenin. Furthermore, in vivo experiments demonstrated that pyrogallol exerted growth inhibition on NSCLC with low toxicity through the same molecular mechanism as observed in vitro. Our findings could contribute to the understanding of the mechanism by which pyrogallol negatively regulates NSCLC growth, which could be effective in treating NSCLC. [ABSTRACT FROM AUTHOR]

This study unveils a novel role of pyrogallol (PG), a recognized superoxide generator, in inducing beta-amyloid (Aβ) secretion in an Alzheimer's disease (AD) cellular model. Contrary to expectations, the analysis of dihydroethidium fluorescence and UV-VIS spectrum scanning reveals that Aβ secretion arises from PG reaction intermediates rather than superoxide or other by-products. Investigation into Aβ secretion mechanisms identifies dynasore-dependent endocytosis and BFA-dependent exocytosis as independent pathways, regulated by tiron, tempol, and superoxide dismutase. Cell-type specificity is observed, with 293sw cells showing both pathways, while H4sw cells and primary astrocytes from an AD animal model exclusively exhibit the Aβ exocytosis pathway. This exploration contributes to understanding PG's chemical reactions and provides insights into the interplay between environmental factors, free radicals, and AD, linking occupational PG exposure to AD risk as reported in the literature.

Abstract Pyrogallol, a natural polyphenol compound (1,2,3‐trihydroxybenzene), has shown efficacy in the therapeutic treatment of disorders associated with inflammation. Nevertheless, the mechanisms underlying the protective properties of pyrogallol against influenza A virus infection are not yet established. We established in this study that pyrogallol effectively alleviated H1N1 influenza A virus‐induced lung injury and reduced mortality. Treatment with pyrogallol was found to promote the expression and nuclear translocation of nuclear factor erythroid‐2‐related factor 2 (Nrf2) and peroxisome proliferator‐activated receptor gamma (PPAR‐γ). Notably, the activation of Nrf2 by pyrogallol was involved in elevating the expression of PPAR‐γ, both of which act synergistically to enhance heme oxygenase‐1 (HO‐1) synthesis. Blocking HO‐1 by zinc protoporphyrin (ZnPP) reduced the suppressive impact of pyrogallol on H1N1 virus‐mediated aberrant retinoic acid‐inducible gene‐I‐nuclear factor kappa B (RIG‐I–NF‐κB) signaling, which thus abolished the dampening effects of pyrogallol on excessive proinflammatory mediators and cell death (including apoptosis, necrosis, and ferroptosis). Furthermore, the HO‐1‐independent inactivation of janus kinase 1/signal transducers and activators of transcription (JAK1/STATs) and the HO‐1‐dependent RIG‐I‐augmented STAT1/2 activation were both abrogated by pyrogallol, resulting in suppression of the enhanced transcriptional activity of interferon‐stimulated gene factor 3 (ISGF3) complexes, thus prominently inhibiting the amplification of the H1N1 virus‐induced proinflammatory reaction and apoptosis in interferon‐beta (IFN‐β)‐sensitized cells. The study provides evidence that pyrogallol alleviates excessive proinflammatory responses and abnormal cell death via HO‐1 induction, suggesting it could be a potential agent for treating influenza.

Background: The appropriate reference value of the urinary protein‐to‐creatinine ratio (PCR) for proteinuria may change when the urinary pyrogallol red (PR) protein assay method is changed to the benzethonium chloride method (BC). This study aimed to evaluate the difference between BC‐based PCR (BC‐PCR) and PR‐based PCR (PR‐PCR) values in children. Methods: We compared the BC‐PCR and PR‐PCR values in the same first‐morning urine samples without significant proteinuria in school urine screening settings. The upper limit of the reference values was set at the 97.5th percentile. Results: Notably, 133 samples from 124 individuals (female: 62%, age: median 12.3 years, range 6.3–16.9 years) were collected between August 2020 and October 2022. The diagnoses included 34 normal individuals and 99 with asymptomatic hematuria. The urinary protein (UP) concentrations measured using the BC (BC‐UP) and PR (PR‐UP) methods were in a linear relationship; however, the BC‐UP concentrations were higher than the PR‐UP concentrations (mean of differences: 11.2, 95% confidence interval (CI): 11.0–13.4 mg/dL). Also, the BC‐PCR values were higher than the PR‐PCR values (mean of differences: 0.090, 95% CI: 0.082–0.098 g/gCr). The BC‐PCR showed a body‐size‐related decrease, reflecting a body‐size‐related urinary creatinine increase. The suggested BC‐PCR reference values for proteinuria were 0.25 and 0.17 g/gCr for elementary (6–12.4 years) and junior high school students (12.5–16 years), respectively. These values were higher than those of the PR‐PCR and need further studies. Conclusions: When evaluating PCR results, the urinary protein assay should be stated. [ABSTRACT FROM AUTHOR]

Because of their capacity to bind metals, metal chelators are primarily employed for therapeutic purposes, but they can also find applications as colorimetric reagents and cleaning solutions as well as in soil remediation, electroplating, waste treatment, and so on. For instance, iron-chelation therapy, which is used to treat iron-overload disorders, involves removing excess iron from the blood through the use of particular molecules, like deferoxamine, that have the ability to chelate the metal. The creation of bioinspired and biodegradable chelating agents is a crucial objective that draws inspiration from natural products. In this context, starting from bioavailable molecules such as maltol and pyrogallol, new molecules have been synthetized and characterized by potentiometry, infrared spectroscopy and cyclic voltammetry. Finally, the ability of these to bind iron has been investigated, and the stability constants of ferric complexes are measured using spectrophotometry. These compounds offer intriguing scaffolds for an innovative class of versatile, multipurpose chelating agents. [ABSTRACT FROM AUTHOR]

In more than 50 to 90% of type 2 diabetic patients, under the influence of various factors, the production of islet amyloid polypeptide or amylin in pancreatic beta cells increases. Spontaneous accumulation of amylin peptide in the form of insoluble amyloid fibrils and soluble oligomers is one of the main causes of beta cell death in diabetic patients. The objective of the present study was to evaluate the effect of pyrogallol, as a phenolic compound, on inhibiting the formation of amylin protein amyloid fibrils. In this study, different techniques such as the thioflavin T (ThT) and 1-Anilino-8-naphthalene sulfonate (ANS) fluorescence intensity and the circular dichroism (CD) spectrum, will be used to investigate the effects of this compound on inhibiting the formation of amyloid fibrils. To investigate the interaction sites of pyrogallol with amylin, docking studies were performed. Our results that pyrogallol in a dose-dependent manner (0.5:1, 1:1, and 5:1, Pyr to Amylin) inhibits the amylin amyloid fibrils formation. Docking analysis revealed that pyrogallol forms hydrogen bonds with valine 17 and asparagine 21. In addition, this compound forms 2 more hydrogen bonds with asparagine 22. This compound also forms hydrophobic bonds with histidine 18. Considering this data and the direct relationship between oxidative stress and the formation of amylin amyloid accumulations in diabetes, the use of compounds with both antioxidant and anti-amyloid properties can be considered an important therapeutic strategy for type 2 diabetes. [ABSTRACT FROM AUTHOR]

Aims To examine the effect of the phenolic compound pyrogallol on staphylococcal biofilm formation. Methods and results In crystal violet biofilm assays, pyrogallol-reduced biofilm formation in Staphylococcus epidermidis ATCC 35984, Staph. epidermidis NRRL-B41021, Staphylococcus aureus USA300, and Staph. aureus Newman, without significantly impairing bacterial viability. Pyrogallol-mediated impairment of biofilm formation was likely due to induction of bacterial oxidative stress, as its effect was greater in catalase-deficient versus WT Staph. aureus , and biofilm production was rescued by exogenous catalase. The effect of pyrogallol on staphylococcal biofilm formation mirrored that of the known oxidant hydrogen peroxide, which also reduced biofilm formation in a dose-dependent manner. Conclusions Pyrogallol reduces biofilm formation in S. aureus and Staph. epidermidis in a mechanism involving induction of bacterial oxidative stress. [ABSTRACT FROM AUTHOR]

• A novel pyrogallol-based dipodal fluorescence probe for Co(II) detection is developed. • The chelator shows excellent binding efficiency towards Co(II) with high binding constants. • It sustains the detection of trace amount of cobalt ions in the presence of many interfering metal ions. • A distinct change in color on addition of Co(II) ions to the probe can offer an additional value to use it as a colorimetric sensor. The present research focuses on the micro-level detection of cobalt ions in biological and environmental samples using a new probe. The probe is a multifunctional symmetrical dipodal molecule with two pyrogallol binding units attached to the malonate scaffold through a propylene spacer. It was synthesized and characterized by 1H NMR, 13C NMR, IR, electronic spectroscopy, and mass spectrometry. The molecule's binding, thermodynamic, and photophysical properties are also described. The designed probe demonstrates an excellent sensing ability for Co(II) based on the ESIPT "OFF-ON" fluorescence mechanism. The experiments explore the high selectivity of the ligand for cobalt sensing over a wide range of metal ions of biological and environmental importance. The fluorescence intensity shows a linear response to Co(II) in 5–100 μM concentration with a detection limit of 8.75 x 10−5 and a 2.65-fold enhancement in the intensity. These results establish its potential application as a fluorescence sensor. The probe is also employed as a colorimetric sensor for the qualitative determination of cobalt ions in DMSO solution. The interesting behavior of the probe motivated us further to study its coordination properties with divalent cobalt in solution. The pre-organized assembly with an appropriate cavity size favors the ligand for an efficient Co(II) encapsulation by coordinating through imine-Ns and aromatic ring-Os donors, giving high formation constants. [ABSTRACT FROM AUTHOR]

One reason for the interest in surface modification of magnetite nanoparticles is to create a physical barrier that inhibits their agglomeration and enhances their dispersion. The other reason is to provide different functionalities to the surface. Various functional groups, such as silanes, amines, and hydroxyls, have been successfully utilized as alternatives to functionalize the surface of magnetite. In this study, pyrogallol was selected to be chemically bonded to the surface of magnetite nanoparticles by bridging two of its hydroxyl groups to the iron of magnetite, leaving one extra hydroxyl group in the molecule for further electrochemical characterization. Therefore, we investigated the electrochemical behavior of pyrogallol in solution and when attached to magnetite nanoparticles. Our results include cyclic voltammetry and chronoamperometry of pyrogallol in solution and on pyrogallol-modified magnetite nanoparticles in media with different pH values on a gold electrode. The functionalization of magnetite was confirmed by TGA and FTIR techniques. Additionally, the size of the modified magnetite-pyrogallol nanoparticles was determined by TEM. The attached pyrogallol molecules on modified magnetite-pyrogallol nanoparticles allowed for the production of a stable colloidal suspension that prevented oxidation and agglomeration. We detailed a mechanism of oxidation of pyrogallol that is consistent with the experimental electrochemical results. Finally, we presented an electrochemical characterization of modified pyrogallol-modified magnetite nanoparticles in supernatant and centrifuged solutions. [ABSTRACT FROM AUTHOR]

As part of our studies on the prevention of lifestyle-related diseases by processed foods, we evaluated the xanthine oxidase (XO) inhibitory activity of barley tea. The XO inhibitory activity of the tea (a hotwater extract of roasted barley) was not as potent as that of another roasted beverage, coffee. However, the activity of an ethyl acetate-soluble substance in the extract was significantly stronger than that in coffee. Purification of the substance revealed that pyrogallol was the most potent compound. After establishing a quantification method for pyrogallol in barley tea, we analyzed correlations between pyrogallol content, roasted grain color, and XO inhibitory capacity of barley tea. The findings suggest that the XO inhibitory activity of barley tea is related to the roasting degree and chroma b* of barley grains through the content of pyrogallol, although other active compounds may be present in barley tea. [ABSTRACT FROM AUTHOR]

Tannins are an important class of secondary metabolites with a wide range of pharmacological effects, due to which they are used in various fields of treatment. In plants of the genus Achillea L., tannins are the dominant class of compounds. This allows the use of plant raw materials and extracts of yarrow for the development of complex herbal and combined formulations of medicines. The search for new sources of natural tannin compounds for pharmaceutical and cosmetic purposes is of significant interest and encourages the improvement of phytochemical research methods of known species of medicinal plants. The aim of the work was to develop a spectrophotometric method for determining the quantitative composition of tannin compounds in terms of gallic acid in the herb of Achillea millefolium L. Materials and methods. The study utilized dried air-dried raw material of yarrow for analysis. The quantitative content of polyphenols in the plant material was determined using a modified UV spectrophotometric method, with calculations based on pyrogallol equivalents. The development of the spectrophotometric technique for determining tannins from the herb of Achillea millefolium L., expressed as gallic acid equivalents, considered the effects of extractant concentration and the degree of plant material grinding. Results. The water extract from the herb of Achillea millefolium L. exhibited a quantitative content of polyphenols, calculated as pyrogallol equivalents, at 2.9781 ± 0.0177 %. It was observed that the particle size of the raw material significantly influenced the yield of active substances. The optimal technological parameters for the developed method involved extracting plant material that was crushed to a size of 0.5–1.0 mm, using 70 % ethanol in a ratio of 1:10, resulting in a yield of 4.08 ± 0.01 %. Conclusions. Based on the obtained results, it is recommended to utilize the developed method, employing gallic acid equivalents, for the quantification of tannins in alcohol-water extracts of yarrow.

The rising incidence of extensively drug-resistant (XDR) Klebsiella pneumoniae, including carbapenem- and colistin-resistant strains, leads to the limitation of available effective antibiotics. Miang, known as chewing tea, is produced from Camellia sinensis var. assamica or Assam tea leaves fermentation. Previous studies revealed that the extract of Miang contains various phenolic and flavonoid compounds with numerous biological activities including antibacterial activity. However, the antibacterial activity of Miang against XDR bacteria especially colistin-resistant strains had not been investigated. In this study, the compositions of phenolic and flavonoid compounds in fresh, steamed, and fermented Assam tea leaves were examined by HPLC, and their antibacterial activities were evaluated by the determination of the MIC and MBC. Pyrogallol was detected only in the extract from Miang and showed the highest activities with an MIC of 0.25 mg/mL and an MBC of 0.25–0.5 mg/mL against methicillin-susceptible Staphylococcus aureus, methicillin-resistant S. aureus, Escherichia coli ATCC 25922, colistin-resistant E. coli, and colistin-resistant K. pneumoniae. The effects on morphology and proteomic changes in K. pneumoniae NH54 treated with Miang extract were characterized by SEM and label-free quantitative shotgun proteomics analysis. The results revealed that Miang extract caused the decrease in bacterial cell wall integrity and cell lysis. The up- and downregulated expression with approximately a 2 to >5-fold change in proteins involved in peptidoglycan synthesis and outer membrane, carbohydrate, and amino acid metabolism were identified. These findings suggested that Miang containing pyrogallol and other secondary metabolites from fermentation has potential as an alternative candidate with an antibacterial agent or natural active pharmaceutical ingredient against XDR bacteria including colistin-resistant bacteria.

Antifouling coatings are critical for many biomedical devices. A simple and universal technique used to anchor antifouling polymers is important in order to expand its applications. In this study, we introduced the pyrogallol (PG)-assisted immobilization of poly(ethylene glycol) (PEG) to deposit a thin antifouling layer on biomaterials. Briefly, biomaterials were soaked in a PG/PEG solution and PEG was immobilized onto the biomaterial surfaces via PG polymerization and deposition. The kinetics of PG/PEG deposition started with the deposition of PG on the substrates, followed by the addition of a PEG-rich adlayer. However, prolonged coating added a top-most PG-rich layer, which deteriorated the antifouling efficacy. By controlling the amounts of PG and PEG and the coating time, the PG/PEG coating was able to reduce more than 99% of the adhesion of L929 cells and the adsorption of fibrinogen. The ultrathin (tens of nanometers) and smooth PG/PEG coating was easily deposited onto a wide variety of biomaterials, and the deposition was robust enough to survive harsh sterilization conditions. Furthermore, the coating was highly transparent and allowed most of the UV and Vis light to pass through. The technique has great potential to be applied to biomedical devices that need a transparent antifouling coating, such as intraocular lenses and biosensors. [ABSTRACT FROM AUTHOR]

The regioselective synthesis of the substituted (4R*,10aR*)-4-aryltetrahydro-2H-chromeno[2,3-d]pyrimidin-2-ones, -pyrimidine-2-thiones and (4R*,5R*,6R*)-5-acetyl-6-aryl-4-(2,4-dihydroxyphenyl)hexahydropyrimidin-2-ones, -hexahydropyrimidine-2-thiones by the reaction of the appropriate 5-acetyl-4-aryldihydropyrimidin-2-ones and -pyrimidine-2-thiones with 1,3-benzenediols was described. A plausible mechanism of the acid catalyzed rearrangement of resorcinol-substituted hexahydropyrimidin-2-ones and -pyrimidine-2-thiones to chromeno[2,3-d]pyrimidin-2-ones and -pyrimidine-2-thiones, respectively, was suggested. [ABSTRACT FROM AUTHOR]

Microbial conversion of aromatic compounds is an emerging and promising strategy for valorization of the plant biopolymer lignin. A critical and often rate-limiting reaction in aromatic catabolism is O-aryl-demethylation of the abundant aromatic methoxy groups in lignin to form diols, which enables subsequent oxidative aromatic ring-opening. Recently, a cytochrome P450 system, GcoAB, was discovered to demethylate guaiacol (2-methoxyphenol), which can be produced from coniferyl alcohol-derived lignin, to form catechol. However, native GcoAB has minimal ability to demethylate syringol (2,6-dimethoxyphenol), the analogous compound that can be produced from sinapyl alcohol-derived lignin. Despite the abundance of sinapyl alcohol-based lignin in plants, no pathway for syringol catabolism has been reported to date. Here we used structure-guided protein engineering to enable microbial syringol utilization with GcoAB. Specifically, a phenylalanine residue (GcoA-F169) interferes with the binding of syringol in the active site, and on mutation to smaller amino acids, efficient syringol O-demethylation is achieved. Crystallography indicates that syringol adopts a productive binding pose in the variant, which molecular dynamics simulations trace to the elimination of steric clash between the highly flexible side chain of GcoA-F169 and the additional methoxy group of syringol. Finally, we demonstrate in vivo syringol turnover in Pseudomonas putida KT2440 with the GcoA-F169A variant. Taken together, our findings highlight the significant potential and plasticity of cytochrome P450 aromatic O-demethylases in the biological conversion of lignin-derived aromatic compounds.

Castration-resistant prostate cancer (CRPC) is an advanced form of prostate cancer associated with poor survival rates. The high proliferation and metastasis rates have made CRPC one of the most challenging types of cancer for medical practitioners and researchers. In this study, the anti-cancer properties and inhibition of CRPC progression by S. neglecta extract and its active constituents were determined using two CRPC cell lines, DU145 and PC3. The ethyl acetate fraction of S. neglecta (SnEA) was obtained using a solvent-partitioned extraction technique. The active constituents of SnEA were then determined using the HPLC technique, which showed that SnEA mainly contained syringic acid, pyrogallol, and p-coumaric acid phenolic compounds. After the determination of cytotoxic properties using the SRB assay, it was found that pyrogallol, but not the other two major compounds of SnEA, displayed promising anti-cancer properties in both CRPC cell lines. SnEA and pyrogallol were then further investigated for their anti-proliferation and apoptotic induction properties using propidium iodide and Annexin V staining. The results showed that SnEA and pyrogallol inhibited both DU145 and PC3 cell proliferation by inducing cell cycle arrest in the G0/G1 phase and significantly decreased the expression of cell cycle regulator proteins (cyclin D1, cyclin E1, CDK-2, and CDK-4, p < 0.001). SnEA and pyrogallol treatments also promoted apoptosis in both types of CRPC cells through significantly downregulating anti-apoptotic proteins (survivin, Bcl-2, and Bcl-xl, p < 0.001) and upregulating apoptotic proteins (cleaved-caspase-9, cleaved-caspase-3 and cleaved-PARP-1, p < 0.001). Mechanistic study demonstrated that SnEA and pyrogallol inactivated the Akt signaling pathway leading to enhancement of the active form of GSK-3β in CRPC cell lines. Therefore, the phosphorylation of β-catenin was increased, which caused degradation of the protein, resulting in a downregulation of β-catenin (unphosphorylated form) transcriptional factor activity. The current results reflect the potential impact of S. neglecta extract and pyrogallol on the management of castration-resistant prostate cancer. [ABSTRACT FROM AUTHOR]

Ammannia baecifera Linn is an important plant in traditional medication system of Bangladesh. In order to give the scientific clarification for using this plant in the treatment of gout, this study was designed to identify the xanthine oxidase (XO) inhibitors present in the extract of Ammannia baecifera leaves along with evaluating its antioxidant effect. First aqueous extract was prepared from leaves and then water insoluble part (WIP) was separated from water soluble part (WSP) as precipitate with ethanol. In DPPH and ABTS assays, WSP with rich amount of phenolic compound exhibited high radical scavenging activity than WIP. WSP also showed potent XO inhibition with IC50: 18.03 ± 1.65 μg/mL value. Using different chromatographic techniques, the key XO inhibitor was isolated from WSP and identified as pyrogallol based on its different spectroscopic data. In XO inhibition assay, pyrogallol (IC50: 11.67 ± 0.45 μg/mL) showed potent inhibitory effect as compared to a known XO inhibitor (allopurinol; IC50 = 27.35 ± 1.15 μg/mL) and it also displayed strong DPPH and ABTS radical scavenging effect. In addition, an inhibition kinetics study indicated that WSP and pyrogallol are mixed competitive inhibitors of XO. The overall results suggest that the presence of pyrogallol as XO inhibitor and free radical scavenger in Ammannia baecifera leaf justifies the traditional uses of this plant. [ABSTRACT FROM AUTHOR]

Recently, developments in the field of cosmetics have led to a renewed interest in hair dyeing. However, damage to the hair during the dyeing process has increased hesitation in attempting hair dyeing. As a result, hair dyes with minimal side effects have been in constant demand, and are being developed. In this study, natural-extract polyphenols, pyrogallol, and gallic acid are coordinated by CuCl2 in a NaCl aqueous solution to form an oligomer, which creates an ion-channel coating on the hair surface to protect it. This work attempts to develop fast, simple, and damage-free hair-dye ingredients based on pyrogallol and gallic acid. The morphology and elements of polyphenols coated on hair are characterized. The results reveal that the hair is dyed with the polyphenol-based dye reagent successfully. Moreover, the thickness of the dyed hair continuously rises ten times after dyeing. The tensile strength of the dyed hair is also measured, showing an upward and downward trend. These results reflect the fact that pyrogallol and gallic acid are considered to be the essential and functional polyphenols, and can build ion blocks on hair, which can create new multifunctional coating materials. [ABSTRACT FROM AUTHOR]

In the last years, research proofs have confirmed that hydrogen sulfide (H2S) plays an important role in various physio-pathological processes, such as oxidation, inflammation, neurophysiology, and cardiovascular protection; in particular, the protective effects of H2S in cardiovascular diseases were demonstrated. The interest in H2S-donating molecules as tools for biological and pharmacological studies has grown, together with the understanding of H2S importance. Here we performed a comparative study of a series of H2S donor molecules with different chemical scaffolds and H2S release mechanisms. The compounds were tested in human serum for their stability and ability to generate H2S. Their vasorelaxant properties were studied on rat aorta strips, and the capacity of the selected compounds to protect NO-dependent endothelium reactivity in an acute oxidative stress model was tested. H2S donors showed different H2S-releasing kinetic and produced amounts and vasodilating profiles; in particular, compound 6 was able to attenuate the dysfunction of relaxation induced by pyrogallol exposure, showing endothelial protective effects. These results may represent a useful basis for the rational development of promising H2S-releasing agents also conjugated with other pharmacophores. [ABSTRACT FROM AUTHOR]

[Display omitted] • MF membranes were hydrophilized by pyrogallol (PG)/ ε -polylysine (EPL) coating. • PG/EPL coating solutions produced crosslinked macromolecular PG/EPL complexes. • PG/EPL complexes were densely and uniformly deposited throughout MF membranes. • Modified membranes showed enhanced permeance and organic antifouling performance. • Modified membranes showed superior oil–water separation and antifouling performance. Microfiltration (MF) membranes need to be hydrophilized to enhance their fouling resistance and applicability. Previous modification strategies are somewhat ineffective and rely on harmful synthetic chemicals. Here, we propose a versatile and ecofriendly strategy to hydrophilize MF membranes via simple coating with the natural compounds, pyrogallol (PG) and ε -polylysine (EPL). The PG/EPL aqueous coating solution produced crosslinked macromolecular PG/EPL complexes via the auto-oxidation of PG and its subsequent reactions with numerous EPL amines. The PG/EPL complexes were densely coated on MF membranes via collective hydrophobic interactions between their abundant PG moieties and membrane surfaces, achieving the excellent hydrodynamic and pH stabilities of the PG/EPL coating. The PG/EPL coating also significantly and uniformly improved the hydrophilicity of the poly(vinylidene fluoride) (PVDF) membrane with no distinct deformation of the membrane pore structure. Hence, the PG/EPL-coated PVDF membrane exhibited remarkably higher organic fouling resistance and water permeance (∼22% enhancement) than its pristine control. Furthermore, the PG/EPL-coated PVDF membrane demonstrated dramatic improvements in oil–water separation (∼27% higher oil rejection) and oil antifouling performance compared with its pristine counterpart. The PG/EPL coating was further extended to hydrophilize other polytetrafluoroethylene and polyethylene MF membranes. The proposed coating strategy provides a versatile and ecofriendly platform for hydrophilizing various membranes. [ABSTRACT FROM AUTHOR]

Scavenging of electrogenerated superoxide radical anion (O2•−) by pyrogallol (PyH3) was investigated on the basis of cyclic voltammetry and in situ electrolytic electron spin resonance spectrum in N,N-dimethylformamide with the aid of density functional theory (DFT) calculations. Quasi-reversible dioxygen/O2•− redox couple was modified by the presence of PyH3, suggesting that O2•− was scavenged by PyH3 through proton-coupled electron transfer (PCET) involving two proton transfer and one electron transfer. DFT calculation suggested that the pre-reactive formation of a hydrogen-bond (HB) complex and the subsequent concerted two-proton-coupled electron transfer characterized by catechol moiety in PyH3 is plausible mechanism that embodies the superior kinetics of the O2•− scavenging by PyH3 as shown in the electrochemical results. Furthermore, it was clarified that the three hydroxyl groups of PyH3 promote the formation of HB complex, in comparative analyses using related compounds, resulting in the promotion of the O2•− scavenging.

The detection of antioxidant activity in plant extracts or in pure compounds can be performed by a large number of methods with different reaction mechanisms, however, the criteria for choosing comparative standards are still not consensual. Thus, the present work intends to compare the antioxidant efficiency of nine substances, namely, gallic acid (GA), pyrogallol (PyG), propyl gallate (nPG), tannic acid (TA), quercetin (Qtn), rutin (Rut), ascorbic acid (Asc), Trolox (6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid) and butyl hydroxytoluene (BHT) using methods, (1) Ferric Reducing Antioxidant Power (FRAP) Assay, (2) Ferric Reducing Power (FRP), (3) Ferric-Ferrozine Antioxidant Capacity (FFAC), (4) Total Phosphomolybdenum Antioxidant Capacity (TAC) and (5) Radical Cation Elimination Assay 2,2' Azinobis(3 Ethylbenzothiazoline 6 Sulfonic Acid) (ABTS). Antioxidant efficacy by the 1,1-diphenyl-2-picrylhydrazine free radical scavenging method was previously described in a preliminary study. The results show that the maximum effectiveness was exhibited by PyG in the ABTS (0.425 ± 0.005 µM) and TAC (0.872 ± 0.075 µM) methods, Qtn in the FRP (5.776 ± 0.020 µM) and FFAC (20.390 ± 0.291 µM) methods and GA in the FRAP (6.765 ± 0.086 µM) and DPPH (1.105 ± 0.003 µM) methods. The results found in this study reveal that the effectiveness of a standard depends on the method applied, and the antioxidant activity of the same standard may present differences between the methods, which suggests that the selection of a comparative standard for the antioxidant activity tests of the extracts of plants or functional foods must be made according to the method to be applied. [ABSTRACT FROM AUTHOR]

Wine is a kind of beverage with a variety of compounds beneficial to human health, which makes it popular all over the world and it contributes importantly to economics. The excessive oxidation of wine has always been a major problem in wine production and storage. Unlike traditional wines which are made from Eurasian grapes, wines made from muscadine grapes (Muscadinia rotundifolia Michx.) can maintain their sensory qualities under natural oxidation conditions for relatively long periods of time despite the insight mechanisms still being unclear. In this study, two muscadine wines, Carlos (CAL) and Noble (NOB), and two traditional wines, Chardonnay (CH) and Marselan (MAS), were chosen for comparison of their compositional alteration during oxidation, in order to analyze the principal components contributing to the antioxidant characteristics of muscadine wines. The DPPH, ORAC, color intensity, and total phenolic content changes during the natural oxidation process were analyzed. Six core significantly changed metabolites (SCMs, avicularin, beta-lactose, delphinidin-3-O-glucoside, ellagic acid, myricetin, and 4-methylcatechol [p < 0.05]) related to the oxidation process were determined. In addition, HPLC–MS was also used to identify pyrogallol which is a unique antioxidant compound in muscadine wine. The present work aims to reveal the crucial antioxidant compounds of muscadine wine and provide valuable information and a new platform for future research on wine oxidation. [ABSTRACT FROM AUTHOR]

Skin wound treatments require efficient and targeted delivery of therapeutic agents to promote fast tissue regeneration and prevent infections. Hydrogels are one of the most popular products in the wound care market, although their use as medicated wound dressings remains a massive challenge when hydrophobic drugs are needed due to the hydrophilic nature of these soft materials. In this study, we developed innovative, dynamic hydrogels based on polyvinyl alcohol (PVA), pyrogallol as a hydrogen bond crosslinker, and casein micelles as hydrophobic reservoirs of silver sulfadiazine (SSD) for enzyme-activated smart delivery at wound sites. The hydrogel formulation was optimized for mechanical strength, viscoelastic behavior, water absorption capacity, and drug-loading efficiency. In vitro drug delivery studies revealed a sustainable release profile of SSD for over 24 h from the micelles within the hydrogel network. Furthermore, biocompatibility evaluation using mouse fibroblast L929 cells demonstrated that the hydrogel did not inhibit cell viability, while in vivo experiments on Caenorhabditis elegans (C. elegans) proved its safety in complex organisms. This versatile hydrogel also has anti-inflammatory and antibacterial effects stemming from the therapeutic polyphenol, which could benefit the healing process. The combination of PVA, pyrogallol, and casein-based nanocarriers could offer an approach to wound healing, providing a new platform for hosting hydrophobic therapeutic substances. Overall, this hydrogel system shows great promise in wound care and could broaden the applications of this family of soft materials for treating various skin injuries., Competing Interests: Declaration of competing interest The authors have no conflicts of interest to declare that are relevant to the content of this article., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The main challenges in clinical applications of mesenchymal stem cells (MSCs) are attributed to their heterogeneity. It is believed that preconditioning of MSCs with active compounds may enhance the expression of potentially therapeutic molecules and thus achieve stable and effective therapeutic outcomes. In the present study, we investigated the mechanism by which pyrogallol increased the therapeutic efficacy of human umbilical cord mesenchymal stem cells (hUCMSCs) against LPS-induced acute lung injury (ALI). hUCMSCs with pyrogallol treatment increased expression of HO-1 at both mRNA and protein levels, accompanied by Kelch-Like ECH-Associated Protein 1 (Keap1) degradation, and upregulation of the Nrf2 protein levels as well as nuclear translocation of Nrf2. Moreover, the modulation of Keap1 and Nrf2 as well as HO-1 upregulation by pyrogallol was reversed by pretreatment with N-acetylcysteine (NAC) and a P38 kinase inhibitor (SB203580). Whereas, NAC pretreatment abrogated pyrogallol-mediated activation of P38 kinase, indicating that pyrogallol-derived ROS led to P38 kinase activation, thus promoting Nrf2/HO-1 signaling. Additionally, we found that the induction of p62 by the pyrogallol-mediated ROS/P38/Nrf2 axis interacted with Keap1 and resulted in autophagic degradation of Keap1, which created a positive feedback loop to further release of Nrf2. Furthermore, the increased expression of HO-1 in pyrogallol-pretreated hUCMSCs led to enhanced inhibitory effects on LPS-mediated TLR4/P–P65 signaling in BEAS-2B cells, resulting in increasing suppression of LPS-indued expression of a series of pro-inflammatory mediators. Compared to untreated hUCMSCs, Sprague-Dawley (SD) rats with pyrogallol-primed hUCMSCs transplantation showed enhanced improvements in LPS-mediated lung pathological alterations, the increased lung index (lung/body ratio), apoptosis of epithelial cells, the activation of TLR4/NF-κB signaling as well as the release of pro-inflammatory mediators. Together, these results suggested that hUCMSCs with pyrogallol pretreatment enhanced the therapeutic efficacy of hUCMSCs, which may provide a promising therapeutic strategy to maximize the therapeutic efficacy of hUCMSC-based therapy for treating LPS-associated ALI. [Display omitted] • Pyrogallol increased expression of HO-1 at both mRNA and protein levels in hUCMSCs through the ROS/P38/Nrf2 axis. • The induction of p62 by pyrogallol created a positive feedback loop for further release of Nrf2. • hUCMSCs with pyrogallol pretreatment enhanced the therapeutic efficacy against LPS-mediated inflammation and lung injury. [ABSTRACT FROM AUTHOR]

One of the major problems caused by repeated subcutaneous insulin injections in patients with diabetes is insulin amyloidosis. Understanding the molecular mechanism of amyloid fibril formation of insulin and finding effective compounds to inhibit or eliminate them is very important, and extensive research has been done on it. In this study, the anti‐amyloidogenic and destabilizing effects of the pyrogallol, as a phenolic compound, on human insulin protein were investigated by CR absorbance, ThT and ANS fluorescence, FTIR spectroscopy, and atomic force microscopy. According to the obtained results, the formation of amyloid fibrils at pH 2.0 and 50°C was confirmed by CR, ThT, ANS, and FTIR assays. Microscopic images also showed the twisted and long structures of amyloid fibrils. Simultaneous incubation of the protein with pyrogallol at different concentrations reduced the intensities of CR, ThT, and ANS in a dose‐dependent manner, and no trace of fibrillar structures was observed in the microscopic images. FTIR spectroscopy also showed that the position of the amide I band in the spectrum of samples containing pyrogallol was shifted. Based on the findings of this study, it can be concluded that pyrogallol can be effective in preventing and suppressing human insulin amyloid fibrils. Practical applications: In recent years, finding a strategy for the treatment of amyloid diseases has been considered by many researchers. Targeting protein aggregates by small organic molecules such as polyphenols is one of the most desirable and effective strategies to prevent and improve amyloid disease, which has received much attention in recent years. 1,2,3‐Trihydroxybenzene, commonly known as pyrogallol (Py), is a phenolic compound like other natural polyphenols that are present in human food sources, including fruits and vegetables, and a variety of edible and medicinal plants. So far, many beneficial activities for pyrogallol such as anti‐cancer, antioxidant, antibacterial, antiviral, and antifungal have been reported in various studies. Since various studies have shown that natural polyphenols have special properties to prevent amyloid disease, the present study could be useful in advancing the design purposes of new anti‐amyloid drugs in the future. [ABSTRACT FROM AUTHOR]

After several billions of years, nature still makes decisions on its own to identify, develop, and direct the most effective material for phenomena/challenges faced. Likewise, and inspired by the nature, we learned how to take steps in developing new technologies and materials innovations. Wet and strong adhesion by Mytilidae mussels (among which Mytilus edulis—blue mussel and Mytilus californianus—California mussel are the most well‐known species) has been an inspiration in developing advanced adhesives for the moist condition. The wet adhesion phenomenon is significant in designing tissue adhesives and surgical sealants. However, a deep understanding of engaged chemical moieties, microenvironmental conditions of secreted proteins, and other contributing mechanisms for outstanding wet adhesion mussels are essential for the optimal design of wet glues. In this review, all aspects of wet adhesion of Mytilidae mussels, as well as different strategies needed for designing and fabricating wet adhesives are discussed from a chemistry point of view. Developed muscle‐inspired chemistry is a versatile technique when designing not only wet adhesive, but also, in several more applications, especially in the bioengineering area. The applications of muscle‐inspired biomaterials in various medical applications are summarized for future developments in the field. [ABSTRACT FROM AUTHOR]

(-)-Epigallocatechin gallate (EGCG) has been associated with multiple beneficial effects. However, EGCG is known to be degraded by the gut microbiota. The present study investigated the hypothesis that microbial metabolism would create major catechol-moiety-containing microbial metabolites with different ability from EGCG to induce nuclear factor-erythroid 2-related factor 2 (Nrf2)-mediated gene expression. A reporter gene bioassay, label-free quantitative proteomics and reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) were combined to investigate the regulation of Nrf2-related gene expression after exposure of U2OS reporter gene or Hepa1c1c7 cells in vitro to EGCG or to its major microbial catechol-moiety-containing metabolites: (-)-epigallocatechin (EGC), gallic acid (GA) and pyrogallol (PG). Results show that PG was a more potent inducer of Nrf2-mediated gene expression than EGCG, with a 5% benchmark dose (BMD5) of 0.35 µM as compared to 2.45 µM for EGCG in the reporter gene assay. EGC and GA were unable to induce Nrf2-mediated gene expression up to the highest concentration tested (75 µM). Bioinformatical analysis of the proteomics data indicated that Nrf2 induction by PG relates to glutathione metabolism, drug and/or xenobiotics metabolism and the pentose phosphate pathway. Taken together, our findings demonstrate that the microbial metabolite PG is a more potent inducer of Nrf2-associated gene expression than its parent compound EGCG. [ABSTRACT FROM AUTHOR]

The shikimate pathway is a necessary pathway for the synthesis of aromatic compounds. The intermediate products of the shikimate pathway and its branching pathway have promising properties in many fields, especially in the pharmaceutical industry. Many important compounds, such as shikimic acid, quinic acid, chlorogenic acid, gallic acid, pyrogallol, catechol and so on, can be synthesized by the shikimate pathway. Among them, shikimic acid is the key raw material for the synthesis of GS4104 (Tamiflu®), an inhibitor of neuraminidase against avian influenza virus. Quininic acid is an important intermediate for synthesis of a variety of raw chemical materials and drugs. Gallic acid and catechol receive widespread attention as pharmaceutical intermediates. It is one of the hotspots to accumulate many kinds of target products by rationally modifying the shikimate pathway and its branches in recombinant strains by means of metabolic engineering. This review considers the effects of classical metabolic engineering methods, such as central carbon metabolism (CCM) pathway modification, key enzyme gene modification, blocking the downstream pathway on the shikimate pathway, as well as several expansion pathways and metabolic engineering strategies of the shikimate pathway, and expounds the synthetic biology in recent years in the application of the shikimate pathway and the future development direction. [ABSTRACT FROM AUTHOR]