Search Results (1,614)

Helicobacter pylori, a spiral-shaped bacterium found in the stomach, is associated with various gastrointestinal and systemic health conditions. Effective suppression of H. pylori is therefore critical for managing gastrointestinal diseases. In a search for natural products with anti-H. pylori activity, the extract of Atractylodes macrocephala rhizoma showed significant inhibitory effects. Chromatographic purification of A. macrocephala extract yielded thirteen compounds, which were identified as ten sesquiterpenes and three polyacetylenes by spectroscopic analysis. The sesquiterpene compounds belong to the eudesmane or eudesmane lactone types and exhibited structure-dependent efficacy. The major eudesmane lactone sesquiterpene, atractylenolide I (1), showed strong inhibitory activity comparable to metronidazole, a positive control, and atractylenolide III (3) also showed good efficacy. However, structural modification such as hydroxylation, methylation, or acetylation of the sesquiterpenes led to reduced activity. In contrast, polyacetylene derivatives displayed only mild inhibitory effects. Further evaluation of the active compounds against three H. pylori strains such as 51, 43504, and 26695 showed that atractylenolide I (1) had potent inhibitory effects against all three strains, with MIC₅₀ values of ranging from 27.3 to 48.6 μM and MIC₉₀ values from 45.4 to 87.2 μM. Atractylenolide III (3) exhibited selective activity against strain 51 with MIC₅₀ value of 89.9 μM. Both compounds also exhibited anti-inflammatory activity with IC₉₀ values of 23.3 and 31.1 μM, respectively, although they showed little effect on urease. This is the first report on the anti-H. pylori efficacy of various constituents of A. macrocephala and comparative analysis of inhibitory effects against several strains, which will provide scientific evidence supporting its potential as therapeutic agent for H. pylori-related infection. Full article

Tanacetum parthenium (Asteraceae) has been traditionally used worldwide for medicinal purposes, and some of its therapeutic uses have been attributed to the pharmacological effects of its secondary metabolites. The root culture of this species might represent a sustainable source of several pharmacologically active compounds. The biomass of a root T. parthenium culture was extracted with methanol and fractionated using column chromatography. Three selected fractions (4TP, 5TP, and 8TP) were analyzed via spectrophotometric, chromatographic, and mass spectrometry techniques and in vitro pharmacological assays. The greatest values for total phenolic and phenolic acid contents and antibacterial activity against Escherichia coli were determined for 4TP. The highest values for total flavonoid and sesquiterpene lactone contents, antioxidant potential, and α-amylase inhibitory effect were determined for 8TP. The antibacterial effect against Staphylococcus aureus was not significantly different among the three fractions. The root culture of T. parthenium is a potential source of several metabolites, such as phenolic acids, fatty acids, coumarins, sesquiterpenoids, and triterpenoids, which are capable of exerting α-amylase inhibition and antioxidant, antibacterial, and cytotoxic effects. Among eight phenolic compounds detected and quantified in the fractions, chlorogenic acid was the most abundant. Full article

Quorum quenching (QQ) is of interest for potential application as a sustainable strategy for bacterial disease control via communication interruption. The QQ enzyme can be used as a good alternative antagonist to combat antibiotic abuse and bacterial resistance. Here, genomic DNA sequencing was performed on N-acyl homoserine lactonase from the deep-sea strain Bacillus velezensis DH82 with Cluster of Orthologous Groups of proteins (COGs) annotation. The homologous sequences with β-lactamase domain-containing protein were predicted to be potential QQ enzymes and were cloned and expressed to study their quorum quenching properties by comparing them with the reported enzyme AiiA_3DHB. The experimental results of enzyme activity analysis and steady-state kinetics, as well as enzyme structure and substrate docking simulations and predictions, all consistently demonstrated that YtnP_DH82 presented superior enzyme structural stability and higher degradation efficiency of N-acyl homoserine lactones than AiiA_DH82 under the effects of pH, and temperature, and performed better on short -chain and 3-O-substituted AHSLs. The findings revealed the structural and biochemical characterization of YtnP_DH82 from the deep sea, which provide the capacity for further application in sustainable aquaculture as an alternative to antibiotics. Full article

Achillea nobilis represents a species of considerable medicinal importance within the Asteraceae family, historically employed in Central Asia and various Eurasian territories for the management of inflammatory, microbial, and gastrointestinal ailments. Notwithstanding its extensive ethnopharmacological significance, the phytochemical profile and pharmacological attributes of its various anatomical components have not been comprehensively investigated. This research endeavor sought to delineate the phytochemical constituents and evaluate the antimicrobial efficacy of ethanol extracts derived from both the aerial and root segments of A. nobilis. Qualitative phytochemical analysis and GC–MS characterization unveiled a diverse array of bioactive compounds, encompassing flavonoids, phenolic compounds, organic acids, lactones, alcohols, and heterocyclic derivatives. In particular, the aerial oil extract exhibited the presence of terpenoids, fatty acids and their esters, sterols, hydrocarbons, and minor organosilicon and cyclobutanone derivatives, with notable compounds such as linoleic acid (8.08%), 6-tetradecyne (14.99%), isopropyl linoleate (14.64%), and E,Z-1,3,12-nonadecatriene (22.25%). In vitro antimicrobial activity was assessed against eight clinically relevant microbial strains employing the broth microdilution technique. The aerial ethanol extract exhibited pronounced antimicrobial properties, particularly against MRSA and C. albicans, with MICs ranging from 0.5 to 2 mg/mL, whereas the root ethanol extract displayed MICs of 1 to 3 mg/mL. Additionally, the aerial oil extract showed moderate inhibitory activity, with MIC values ranging from 1.5 to 3 mg/mL, demonstrating effectiveness particularly against C. albicans, C. neoformans, and MRSA. These findings underscore the therapeutic potential of A. nobilis, particularly its aerial component, as a viable natural source of antimicrobial agents. Full article

Resorcylic acid lactones (RALs) are fungal metabolites with known biological activity. Zeranol, a synthetic RAL, has been used as an estrogenic growth promoter in cattle; however, its use is prohibited in several countries. Zearalenone, a mycotoxin produced by Fusarium spp., is commonly found in contaminated animal feed and can be metabolized into other RALs, which are subsequently excreted in urine. To differentiate between natural contamination from feed and the illegal administration of zeranol, the European Union Reference Laboratory for Growth Promoters (EURL) developed a mathematical equation. This study aims to evaluate the detection and quantification of RALs in bovine urine from animals fed zearalenone-contaminated diets, implanted with zeranol, or subjected to both conditions. RALs were detected and quantified in the urine of cattle consuming contaminated corn, while zeranol and taleranol were identified in the urine of implanted animals. The EURL equation proved to be a valuable tool for determining the origin of RALs in bovine urine and holds significant potential for monitoring and enforcing regulations regarding the illegal use of zeranol. Full article

Background/Objective: Cerivastatin (Cer), a cholesterol-lowering statin, was withdrawn from the market due to fatal cases of rhabdomyolysis, particularly when co-administered with gemfibrozil (Gem), a strong CYP2C8 inhibitor. However, the pharmacokinetic (PK) mechanisms underlying these adverse events remain unclear. This study investigates the impact of drug–drug interactions (DDIs) involving Gem and itraconazole (Itr), a potent CYP3A4 inhibitor, on plasma concentrations of Cer and its major metabolites—M23, M1, and cerivastatin lactone (Cer-L)—with a focus on the risk of excessive Cer-L accumulation. Methods: We applied a newly developed Metabolite-Linked Model that simultaneously characterizes parent drug and metabolite kinetics by estimating metabolite formation fractions (f_M) and elimination rate constants (K_eM). The model was calibrated using observed DDI data from Cer + Gem and Cer + Itr scenarios and then used to predict outcomes in an untested Cer + Gem + Itr combination. Results: The model accurately reproduced observed metabolite profiles in single-inhibitor DDIs. Predicted AUCR values for Cer-L were 4.2 (Cer + Gem) and 2.1 (Cer + Itr), with reduced K_eM indicating CYP2C8 and CYP3A4 as primary elimination pathways. In the dual-inhibitor scenario, Cer-L AUCR reached ~70—far exceeding that of the parent drug—suggesting severe clearance impairment and toxic accumulation. Conclusions: Dual inhibition of CYP2C8 and CYP3A4 may cause dangerously elevated Cer-L levels, contributing to Cer-associated rhabdomyolysis. This modeling approach offers a powerful framework for evaluating DDI risks involving active or toxic metabolites, supporting safer drug development and regulatory assessment. Full article

Biofilm-associated infections caused by Gram-negative bacteria, especially multidrug-resistant strains, frequently occur in intensive care units and represent a major therapeutic challenge. The economic burden of biofilm-associated infections is considerable, making the search for new treatment approaches a focal point for policymakers and scientific funding bodies. Biofilm formation is regulated by quorum sensing (QS), a population density-dependent communication mechanism between cells mediated by small diffusible signaling molecules. QS modulates various intracellular processes, and some features of QS are common to all Gram-negative bacteria. While there are differences in the QS regulatory networks of different Gram-negative bacterial species, a common feature of most Gram-negative bacteria is the ability of N-acylhomoserine lactones (AHL) as inducers to diffuse across the bacterial membrane and interact with receptors located either in the cytoplasm or on the inner membrane. Targeting QS by inhibiting the synthesis, transport, or perception of signaling molecules using small molecules, quorum quenching enzymes, antibodies, combinatorial therapies, or nanoparticles is a promising strategy to combat virulence. In-depth knowledge of biofilm biology, antibiotic susceptibility, and penetration mechanisms, as well as a deep understanding of anti-QS agents, will contribute to the development of antimicrobial therapies to combat biofilm infections. Advancing antimicrobial therapies against biofilm infections requires a deep understanding of biofilm biology, antibiotic susceptibility, penetration mechanisms, and anti-QS strategies. This can be achieved through in vivo and clinical studies, supported by state-of-the-art tools such as machine learning and artificial intelligence. Full article

Ascorbic acid (ASC) is a furan-based lactone derived from 2-ketogluconic acid that functions as a major antioxidant and redox buffer in mature plant tissues, although its content is lower in meristematic cells. ASC is commonly considered a reactive oxygen species (ROS) scavenger; however, its role in the regulation of plant development remains unclear. Additionally, the chemical behavior of ascorbate warrants special attention during ASC supplementation in in vitro plant culture. In this study, I investigated in detail the behavior of ascorbate in plant tissue culture medium and its uptake by plants. As a secondary objective, the role of ascorbate in root growth regulation was evaluated. The effects of low ASC levels on root architecture and its interaction with auxin signaling were studied using the vtc1 and vtc2 mutants of Arabidopsis thaliana, as well as through external ascorbate supplementation. Several marker lines for auxin response/distribution were used, along with direct ascorbate measurement via HPLC. Reducing ascorbate content through mutations had no significant effect on root development or auxin signaling, whereas high-concentration ASC supplementation inhibited both auxin signaling and root development, as demonstrated using auxin response and transport markers. At the organ level, ASC supplementation significantly downregulated auxin response-mediated cell cycle activation during lateral root induction. Based on the data presented, exogenous ascorbate may regulate root development through its interaction with auxin signaling pathways. Full article

Cichorium intybus L. (common chicory) is a medicinal plant valued for health-promoting effects. Although analgesic properties are known for chicory sesquiterpenes, the effects of extracts need yet to be explored. This study aimed to evaluate for the first time the analgesic effect (against nociceptive pain) of the root extract from C. intybus var. foliosum. The target evaluation was preceded by toxicity tests in vivo and phytochemical standardization of root extracts prepared with different extraction methods—pectinase-assisted, pressure-assisted, and a combination of both—to choose the most effective one. The phytochemical profiling involved UHPLC-PDA-ESI-MS/MS and UHPLC-PDA analyses. The toxicity and the analgesic effects were tested in mice following the OECD 423 guideline and the hot-plate test, respectively. The highest recovery of bioactive compounds was achieved for the pressure-assisted extract: 642.5 mg sesquiterpene lactones, 187.1 mg phenolic acids, and 47.3 g inulin/100 g of dry matter. The extract showed no toxic effects at the oral dose of 2000 mg/kg body weight, including no histopathologic changes, in mice within two weeks (GHS Category 5/Uncategorized). The maximum analgesic effect (MAE) of the extract at 600 mg/kg was 6.75% for rearing and 13.7% for jumping, with the impact on the nocifensive reactions not differing significantly from those of paracetamol at 60 mg/kg. Despite the relatively low effects at 600 mg/kg, the verified safety and abundance of active compounds encourage further studies on the extract and its active fractions as potential approaches to complementary pain therapy, with special concern for their mechanisms of action. Full article

This review presents information obtained over the past 10 years on the methods to control the widespread worldwide phytopathogen Pectobacterium carotovorum subsp. carotovorum (Pcc). This bacterium is among the ten most dangerous phytopathogens; it affects a wide range of cultivated plants: vegetables, ornamental and medicinal crops, both during vegetation and during the storage of fruits. Symptoms of Pcc damage include the wilting of plants, blackening of vessels on leaves, stems and petioles. At the flowering stage, the stem core gradually wilts and, starting from the root, the stem breaks and the plant dies. Pcc is a rod-shaped, non-capsule and endospore-forming facultative anaerobic Gram-negative bacterium with peritrichous flagellation. Pcc synthesizes bacteriocins—carocins. The main virulence factors of Pcc are the synthesis of N-acyl-homoserine lactone (AHL) and plant cell wall-degrading enzymes (PCWDEs) (pectinases, polygalacturonases, cellulases, and proteases). Diagnostic methods for this phytopathogen include polymerase chain reaction (PCR), loop-mediated isothermal amplification (LAMP), multilocus genotyping of strain-specific genes and detection of unique volatile organic compounds (VOCs). The main methods to control this microorganism include the use of various chemicals (acids, phenols, esters, salts, gases), plant extracts (from grasses, shrubs, trees, and algae), antagonistic bacteria (Bacillus, Pseudomonas, Streptomyces, and lactic acid bacteria), viruses (including a mixture of bacteriophages), and nanomaterials based on metals and chitosan. Full article

Wine aroma is the result of the association of numerous volatile and non-volatile compounds belonging to the grapes, the fermentation, and aging process. During aging, wines complete their complex composition, and many aromas emerge. Therefore, aging represents a fundamental step to obtaining high-quality wines. Aromas belong directly to the odorless precursor in grapes or to the aging technology used. Analyses have been performed on wines obtained from the cv Carignano subjected to four aging technologies: stainless-steel tank, plastic vat, concrete vat, and oak barrel. GC/FID and GC/MS analysis allowed the identification of 78 significant compounds belonging to eight different chemical classes. Volatile composition in the various containers was assessed at two levels: chemical classes and individual compounds. At 12 months, plastic vats had the highest increase in the total VOC concentration (p < 0.05), followed by concrete and stainless steel. In contrast, oak barrels showed a decrease, although the difference was not statistically significant (p > 0.05). Unsupervised principal component analysis (PCA) demonstrated that the container exerts a more substantial influence at 6 months, while at 12 months, the samples were categorized irrespective of the container. In the loading plot, several esters, acids, lactones, and aldehydes showed negative loadings on PC1 (associated with time), indicating a correlation with the 12-month collection time. Full article

Background: Topical statin therapy holds promise for ocular diseases, such as age-related macular degeneration, but the effective delivery to the posterior segment is limited by poor aqueous solubility, chemical instability, and ocular barriers. Cyclodextrins (CDs) can enhance statin solubility and stability; however, the behavior of CD–statin complexes in aqueous eye drops—particularly their influence on the equilibrium between the inactive lactone (ring closed) and active hydroxyacid forms (ring open)—remains unclear. This study aimed to (i) investigate how 5% and 10% (w/v) concentrations of selected CDs affect the lactone/acid equilibrium of simvastatin and atorvastatin and (ii) define formulation parameters (statin form, CD type and concentration, and pH range) for stable eye drop development. Methods: Simvastatin or atorvastatin was added to buffered solutions (pH 2.0 to pH 9.5) of RMβCD, HPβCD, γ-CD, or SBEβCD at 0%, 5%, and 10% (w/v), incubated at 23 ± 1 °C, and sampled over time for UPLC quantification of lactone and hydroxyacid forms, and rate constants for the forward and reverse reaction were calculated. Phase solubility studies were also conducted to further characterize equilibrium behavior in aqueous CD systems. Results: The lactone form was most stable at a pH of 4.5, while the hydroxyacid form prevailed at a pH ≥ 7. γ-CD and HPβCD accelerated lactone hydrolysis for both statins, whereas RMβCD exerted a stabilizing effect. Increasing the CD concentration from 5% to 10% provided minimal additional stabilization. Conclusions: These findings highlight that the precise control of the pH, an appropriate cyclodextrin choice, and the selection of the statin form are critical to developing chemically stable eye drops. Full article

Chrysanthemum species represent an economically important group of flowering plants. Many species also present a medicinal interest, notably for the treatment of inflammatory pathologies. This is the case for Chrysanthemum boreale Makino, endemic to Japan and widespread in Eastern Asia. This perennial plant has long been used in folk medicine to treat inflammatory diseases and bacterial infections. An extensive review of the scientific literature pertaining to C. boreale has been performed to analyze the origin of the plant, its genetic traits, the traditional usages, and the properties of aqueous or organic plant extracts and essential oils derived from this species. Aqueous extracts and the associated flavonoids, such as acacetin and glycoside derivatives, display potent antioxidant activities. These aqueous extracts and floral waters are used mainly as cytoprotective agents. Organic extracts, in particular those made from methanol or ethanol, essentially display antioxidant and anti-inflammatory properties useful to protect organs from oxidative damage. They can be used for neuroprotection. Essential oils from C. boreale have been used as cytoprotective or antibacterial agents. The main bioactive natural products isolated from the plant include flavonoids such as acacetin and related glycosides (notably linarin), and diverse sesquiterpene lactones (SLs). Among monomeric SLs, cumambrins and borenolide are the main products of interest, with cumambrin A targeting covalently the transcription factor NF-κB to regulate proinflammatory gene expression to limit osteoclastic bone resorption. The dimeric SL handelin, which is characteristic of C. boreale, exhibits a prominent anti-inflammatory action, with a capacity to target key proteins like kinase TAK1 and chaperone Hsp70. A few other natural products isolated from the plant (tulipinolide, polyacetylenic derivatives) are discussed. Altogether, the review explores all medicinal usages of the plant and the associated phytochemical panorama, with the objective of promoting further botanical and chemical studies of this ancestral medicinal species. Full article

The Atacama Desert is emerging as an unexpected source of microbial life and, thus, a source of bioactive compounds and novel enzymes. Baeyer–Villiger monooxygenases (BVMOs), a subclass of flavin-dependent monooxygenases (FPMOs), have gained attention as promising biocatalysts for the biosynthesis of industrially relevant molecules for a wide range of applications, such as pharmaceuticals and polymers, among others. BVMOs catalyze the oxidation of ketones and cyclic ketones to esters and lactones, respectively, by using molecular oxygen and NAD(P)H. BVMOs may also catalyze heteroatoms oxidation including sulfoxidations and N-oxidations. This work aims to search for novel BVMOs in the genomes of new bacterial strains isolated from the Atacama Desert. Bioinformatic analysis led to the identification of 10 putative BVMOs, where the monooxygenase named MO-G35A was selected. Genome context showed, downstream of the MO-G35A, a gene encoding for an enzyme from the short-chain dehydrogenase/reductase family, suggesting a closer redox loop between both enzymes. MO-G35A was successfully expressed in three Escherichia coli expression systems, where higher yields were achieved using the E. coli Shuffle T7 as host, suggesting that correct disulfide bond formation is necessary for correct folding. Enzyme characterization showed that it operates optimally at 35–38 °C, exhibiting a Km of 0.06 mM and a kcat of 0.15 s⁻¹ for bicyclo [3.2.0] hept-2-en-6-one (BHC). Furthermore, the study revealed high stability in the presence of organic solvents, making it suitable for applications in various industrial processes, especially when the substrates have poor solubility in aqueous solutions. These results highlight the robustness and adaptability of enzymes in extreme environments, making them valuable candidates for biotechnological applications. Full article

Objectives: Nanosized polymeric micelles (PMs) with an average size of about 80 nm and moderately positive ζ potential, based on an amphiphilic poly(4-methyl-piperazin-1-yl)-propenone)-b-polylactide (PMPP-PLA) block copolymer, were prepared. They were used as platforms for the delivery of bioactive sesquiterpene lactones from Inula helenium L. root extract. Methods: The PMs were characterized with good encapsulation efficiency as a maximum value of 72% was reached at a polymer-to-extract mass ratio of 10:1. The loaded micelles exhibited good colloidal stability. An in vitro release was performed showing a burst release profile. The biocompatibility of the resulting PMs was confirmed by assessing their cytotoxic effect on human keratinocytes in vitro by colorimetric assay and flow cytometry. Results: The systems demonstrated the capability to reduce the biomass of pre-formed Gram-positive and Gram-negative bacterial biofilms. Conclusions: The obtained data clearly determine a trend for a strong combined effect between the PMs and the root extract, distinguishing them with an excellent anti-biofilm potential and prospects for future applications in medical practice. Full article