Search Results (1,116)

The accumulation of histamine in fish products represents a significant food safety issue, particularly in skipjack tuna (Katsuwonus pelamis), due to its elevated histidine content. This study sought to isolate histamine-producing bacteria from skipjack tuna and assess the inhibitory effects of six plant-derived essential oils on bacterial proliferation and histamine synthesis. Seven bacterial isolates were obtained and screened, with histamine concentrations quantified via high-performance liquid chromatography (HPLC) following dansyl chloride derivatization. The isolate exhibiting the highest histamine production (1.2 ± 0.2 mM) was identified as Aeromonas hydrophila through 16S rDNA sequencing. Essential oils were administered to bacterial cultures prior to histamine quantification, and their minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) were determined in vitro. Among the tested oils, oregano and cinnamon demonstrated the strongest antibacterial activity, with MIC and MBC values below 1 mg/mL. Scanning electron microscopy analysis revealed pronounced structural damage to bacterial cells treated with these oils. At the MBC, histamine production was entirely suppressed; at half the MBC, histamine synthesis was reduced by more than 90%, whereas lower concentrations yielded moderate inhibition ranging from 15% to 22%. These findings suggest that selected essential oils, notably oregano and cinnamon, possess considerable potential as natural preservatives to reduce histamine formation in skipjack tuna. However, further investigation is necessary to confirm their effectiveness under practical storage conditions. Full article

Methicillin-resistant Staphylococcus aureus (MRSA) remains a significant multidrug-resistant pathogen, frequently associated with persistent infections and biofilm formation, underscoring the urgent need for alternative antimicrobial strategies. Bioactive compounds derived from fungi have attracted considerable attention due to their structural diversity and demonstrated antibacterial activity against MRSA. This study employed a scientometric approach to assess global research trends, thematic evolution, and collaborative networks concerning fungi-derived anti-MRSA compounds. Bibliographic data were collected from the Scopus database, and a total of 1666 English-language articles and reviews published up to 2025 were analyzed using Bibliometrix/Biblioshiny and VOSviewer. The findings indicate a marked increase in research output after 2010, reflecting heightened scientific interest in fungal natural products for MRSA management. China and the United States emerged as leading contributors in terms of publication volume and international collaboration. Thematic analysis revealed a shift from broad antimicrobial screening to more specialized investigations, including antibiofilm activity, secondary metabolites, endophytic fungi, molecular docking, and antimicrobial resistance. Nonetheless, several challenges persist, such as insufficient mechanistic validation, limited toxicity and pharmacokinetic assessments, and a lack of clinically relevant in vivo studies. Overall, the field is increasingly multidisciplinary, integrating microbiology, natural product chemistry, and computational methodologies to advance the discovery of anti-MRSA agents. Full article

Background/Objectives: Resistant pathogenic bacteria and fungi are a growing problem worldwide; therefore, the discovery of new active ingredients is an important challenge for which the functionalization of natural terpenes with biologically active heterocycles can provide a basis. To reach this goal, a series of 1,4-disubstituted-1,2,3-triazole conjugates was designed and synthesized starting from commercially available α-santonin. Methods: The key azido derivative intermediate was prepared according to literature procedures via Michael addition between dehydrosantonin and the TMSN₃/AcOH/Et₃N system at its highly reactive α-methylene-γ-lactone motif. Subsequently, the obtained azide was applied to regioselective Huisgen 1,3-dipolar cycloaddition reaction with a wide range of terminal alkynes bearing N-, S- and O-heterocycles. These include pyridine, pyrimidine, purine, quinoline, indol, or coumarin to afford the sesquiterpene–heterocycle chimaeras. All triazole conjugates were screened for in vitro antiproliferative activity by MTT assay against HeLa, MDA-MB231, SiHa, MCF-7 and A2780 human cancer cell lines compared with fibroblast cells (NIH/3T3) to check their cytotoxicity and antimicrobial effects on two Gram-positive (B. subtilis, S. aureus) pathogenic bacteria, two Gram-negative (E. coli and P. aeruginosa) pathogenic bacteria, and two yeasts (C. krusei and C. albicans). Results: The results indicated that most of the examined compounds expressed weak activity against human cell lines, while some of them showed moderate activity against S. aureus (up to 99% inhibition at 100 µg/mL conc.), C. krusei (up to 51% inhibition at 10 µg/mL conc.) and C. albicans (up to 52% inhibition at 10 µg/mL conc.). Conclusions: Further structural modification of the best, selective antibacterial and antifungal compounds may open the possibility to the development of effective natural sesquiterpene-based selective antimicrobial agents. Full article

(1) Background: The increasing antibiotic resistance of pathogens is necessitating new therapies that target virulence factors. Virulence factors include biofilm formation, which is a key pathogenic factor involved in bacterial pathogenicity and resistance. (2) Methods: Initially, biofilm formation assays were performed to screen the biofilm formation inhibition effects of gastrodin. A bacterial growth assay was performed to examine the synergistic effects and qRT-PCR was performed to identify the underlying molecular regulatory mechanisms. (3) Results: Gastrodin inhibits biofilm formation by bacteria such as E. faecalis (IC₅₀ = 1.56 μg/mL), E. faecium (IC₅₀ = 0.19 μg/mL), S. aureus (IC₅₀ = 6.25 μg/mL), C. acnes (IC₅₀ = 0.78 μg/mL), S. sobrinus (IC₅₀ = 12.5 μg/mL), P. aeruginosa (IC₅₀ = 25.00 μg/mL), and E. coli (IC₅₀ = 25. 10 μg/mL) without directly affecting bacterial growth, as shown by bacterial growth assay. Gastrodin also reduced the expression of cytolysin genes (cylLS, cylR2, and cylM), quorum sensing genes (fsrB, fsrC, gelE, ebpA, ebpB, acm, scm, and bps) and biofilm virulence genes (esp) as shown by qRT-PCR analysis and exhibited dramatic synergistic antibacterial effects in the growth assay. (4) Conclusions: These results suggest that gastrodin may be a promising novel antibacterial adjuvant for biofilm-related bacterial infections, but further experiments, including in vivo assays, are still needed. Full article

Multidrug-resistant bacterial pathogens pose a critical global health challenge, necessitating safe and effective antimicrobial alternatives. Plant-derived nanoparticles represent promising candidates due to their bioactivity and biocompatibility. Magnesium nitrate nanoparticles were synthesized using Momordica charantia peel extract through green chemistry. Phytochemical screening identified flavonoids, phenolics, tannins, and terpenoids that facilitated nanoparticle formation and stability. Characterization via scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and Fourier transform infrared spectroscopy confirmed polydisperse size distribution (1–100 nm), crystalline structure, and functional group capping. Disc diffusion assays demonstrated concentration-dependent antibacterial activity against multidrug-resistant strains, with maximum inhibition zones of 17.6 ± 1.1 mm against Gram-positive bacteria. Minimum inhibitory concentration and minimum bactericidal concentration assays revealed high bactericidal activity, particularly against Gram-positive bacteria. Time-kill kinetic studies showed concentration- and time-dependent killing with ≥3 log₁₀ reduction in viable bacterial counts at higher concentrations. Nanoparticle–antibiotic combinations exhibited markedly enhanced activity against multidrug-resistant strains compared to free antibiotics, indicating synergistic effects. Toxicity assessment using Brine Shrimp Lethality Assay revealed low toxicity (LC₅₀ > 1000 µg/mL). Green-synthesized magnesium nitrate nanoparticles demonstrate potent antibacterial properties and effectively enhance antibiotic potency against multidrug-resistant bacteria. Further studies are required to validate therapeutic applicability. Full article

Imaging of infections has the potential to improve clinical outcomes, but pathogen-specific imaging strategies are currently unavailable. Given their target specificity, antimicrobials may be useful as molecular imaging ligands to target infections. Despite substantial development efforts, no antimicrobial-based ligands are approved for clinical use. This scoping review comprehensively surveys radiolabeled antimicrobials across antibacterial, antimycobacterial, antiviral, and antifungal drug classes, examining their progression through the translational pipeline. The review utilized PubMed and Google Scholar databases (1970–2025), following PRISMA Extension for Scoping Reviews (PRISMA-ScR) guidelines. Two reviewers independently screened titles, abstracts, and full-text articles; data were extracted, and content duplicates were removed. In total, 143 preclinical and 25 clinical articles met the selection criteria. In clinical studies, most tracers showed suboptimal specificity for infections, while some proved useful for pharmacokinetic characterization. Among preclinical studies, radiolabeled plazomicin and echinocandins (caspofungin and anidulafungin) exhibited the greatest number of preferred characteristics. In conclusion, ideal antimicrobial pharmacologic properties can be counterproductive for imaging, where rapid background clearance and a high target-to-non-target ratio (T/NT) are essential. Many radioligands demonstrate good tissue penetration but suboptimal washout, limiting their diagnostic value. In vivo pharmacokinetic applications during active infections are promising, though significant challenges remain for infection imaging. Full article

Chicken feet, an abundant and low-cost poultry by-product rich in collagen, were used to extract gelatin, which was then formulated into active biodegradable films containing food-grade clove essential oil (CEO), glycerol, sorbitol, and Tween 20. Gelatin extraction involved 0.5 M NaOH pretreatment followed by 5% acetic acid extraction at 66 °C, yielding 11.22% gelatin. Eight gelatin–CEO films were prepared by varying the CEO concentration and plasticizer composition. The supplier-declared CEO composition was eugenol-dominant, and antibacterial activity against Escherichia coli, Kluyvera sp., and Enterobacter cloacae was assessed by agar disk diffusion, MIC, and MBC assays, each performed in triplicate. CEO inhibition zones of 22, 14, and 19 mm were recorded against E. coli, Kluyvera sp., and E. cloacae, respectively; the blank 6 mm control disks without oil produced no inhibition halo beyond the disk edge. MIC/MBC values were 5/6, 3/4, and 4/5 mg/mL for the same three strains. All films were continuous, smooth, and peelable; sorbitol-containing formulations were clearer and more flexible than sorbitol-free variants. Water solubility ranged from 37.67% to 48.78%, opacity from 5.26 × 10⁻³ to 9.20 × 10⁻³ A500 mm⁻¹, and thickness from 11.75 to 23.75 µm. Water vapor transfer was undetectable under the gravimetric screening protocol for all formulations. All films showed complete visual disappearance in soil within 6–10 days. In the cherry tomato trial, the best-performing coatings extended acceptable storage from about 5 days (uncoated control) to 10 days at 17–20 °C. Full article

The incidence of levofloxacin and metronidazole resistance in H. pylori Indonesian strains is increasing. Conventional approaches to antibacterial discovery are often a protracted process. This study uses structure-based virtual screening to quickly discover anti-H. pylori. This study employed homology modeling, docking, ADMET prediction, and molecular dynamics simulation to evaluate phytochemicals against resistant H. pylori gyrA, gyrB, and rdxA structures from Indonesian strains. Three-dimensional structures were constructed from the amino acid sequences gyrA, gyrB, and rdxA of levofloxacin- and metronidazole-resistant H. pylori Indonesian strains. The results of redocking at the binding sites gyrA (0.13 Å), gyrB (0.0024 Å), and rdxA (0.5 Å) obtained a valid RMSD. Curcumin exhibited the lowest average binding scores across gyrA (−154.994 kcal/mol), gyrB (−159.2033 kcal/mol), and rdxA (−166.322 kcal/mol) compared to other compounds and standard therapies, including levofloxacin (−109.1553 and −122.5873 kcal/mol) and metronidazole (−85.6096 kcal/mol). Molecular dynamics simulation results revealed that the curcumin–gyrA complex exhibited comparatively more restrained fluctuation than the other complexes throughout the simulation, as indicated by a consistently low total RMSD value (4–7 Å). Curcumin demonstrated the most favorable computational interaction profile among the evaluated compounds. Full article

Bismuth oxide (Bi₂O₃) nanoparticles are attractive for biomedical and radiation-shielding technologies and can be further tailored through the addition of other metal oxides to address emerging needs such as antimicrobial resistance. This study investigated the effects of incorporating Fe₂O₃ and La₂O₃ on the structure, morphology, and antimicrobial performance of Bi₂O₃-based nanocomposites synthesized via a plant extract-assisted microwave–hydrothermal route using soapnut extract. XRD indicated that pure Bi₂O₃ (100B) comprised predominantly monoclinic α-Bi₂O₃ with coexisting metastable tetragonal β-Bi₂O₃. The addition of Fe (3F; Fe:Bi = 30:70) promoted β- Bi₂O₃ and formed BiFeO₃, while increasing La substitution (3L–20L) reduced the BiFeO₃ intensity and, beyond a threshold (≥7L), yielded distinct La₂O₃ peaks consistent with a La₂O₃–BiFeO₃–Bi₂O₃ composite. Crystallite size decreased from ~46 nm (100B) to ~25 nm (3F), varying with La between 33 and 25 nm. SEM/TEM revealed a reflection in morphology and size with composition from disk-like particles to petal-like spherical aggregates. Antimicrobial screening revealed composition-dependent inhibition: against S. aureus, 20L was the most potent (~94%). Overall, La/Fe tuning under a plant extract-assisted microwave–hydrothermal route enabled phase- and morphology-controlled Bi₂O₃-based nanocomposites with enhanced antimicrobial activity, with ultrafine, high-surface-area architectures emerging as promising antibacterial candidates. Full article

The composition, differences, and metabolic mechanisms of phenolic compounds in fruits and peels of three different varieties (including Clausena lansium ‘Jixin’, ‘Seedless’ and ‘Bingtang’) were investigated. The results showed that the total phenolic content in the fruits followed the order CLB (2080.14 mg/kg) > CLS > CLJ, while in peels it followed CLSp (2457.56 mg/kg) > CLJp > CLBp. Significant differences were observed in flavanols, flavonols, lignans, and phenolic acids among samples. A total of 12 (in fruits) and 9 (in peels) differential phenolic compounds (VIP > 1) were screened. Compared with CLB, several antioxidants and antibacterial phenolics were significantly up-regulated in CLS and CLJ. Pathway analysis revealed that fruit differences were mainly enriched in phenylpropanoid biosynthesis and flavone/flavonol biosynthesis pathways, whereas peel differences were mainly enriched in flavonoid biosynthesis and flavone/flavonol biosynthesis pathways. These findings provided a theoretical basis for wampee variety identification, improvement, and functional evaluation. Full article

Freeze-drying is the most commonly used method for preserving probiotics. The freeze tolerance of probiotics has a significant impact on both their survival rate and the expression of their functional properties. To enhance the freeze tolerance of probiotics, this study established an adaptive evolution protocol combining cold stress with repeated freeze–thaw cycles to screen for freeze–thaw-tolerant evolved strains of Lacticaseibacillus rhamnosus MP108. The safety, metabolic, and functional characteristics of these strains were then evaluated. The results showed that the combination of the 8 h cold stress treatment at 4 °C and nine cycles of freezing and thawing at −20 °C effectively enhanced the strain’s freeze tolerance, and the evolved strain L134 was successfully screened through adaptive evolution. Its freeze-dried survival rate and storage survival rate after 6 months of storage were both significantly higher than those of the parental strain (p < 0.05). Furthermore, it exhibited good passage stability. At the same time, the safety and acid-producing characteristics of L134 did not show significant changes compared to the parental strain. Furthermore, its tolerance to simulated gastric fluid, antibacterial activity, and antioxidant capacity were significantly enhanced (p < 0.05). In particular, compared to MP108, L134 exhibited significantly increased hydroxyl radical scavenging capacity as well as higher activities of the antioxidant enzymes SOD and CAT (p < 0.05); the improvement in its freeze tolerance may be related to this enhanced antioxidant capacity. Full article

15,16-Dihydrotanshinone I (DHT) is a prominent lipophilic diterpenoid from Salvia miltiorrhiza with significant pharmacological potential, though its therapeutic application is limited by poor aqueous solubility. In this study, a microbial biotransformation strategy using Ganoderma lingzhi, known for its wide variety of enzyme, was employed to diversify the chemical structure of DHT and improve its bioactivity profile. Through systematic screening and optimization of fermentation conditions, seven transformation products were isolated and characterized. Among these, five are reported as novel compounds: 17-hydroxy-salvianone (A), 18,19-dihydroxy-danshinspiroketallactone (B-2), epi-18,19-hydroxy-danshinspiroketallactone (B-3), 20-hydroxy-salvianone (C), and 19-hydroxy-danshinspiroketallactone (D). Biological evaluations demonstrated that these derivatives possess multi-target therapeutic potential, including moderate cytotoxic effects against 4T1 and A549 cancer cell lines, alongside anti-inflammatory and neuroprotective activities. However, no significant antibacterial activity was observed for any of the derivatives against six common pathogens. Specifically, compound A significantly inhibited nitric oxide (NO) production in LPS-stimulated RAW 264.7 cells, while B-3 protected SH-SY5Y cells against ${\mathrm{H}}_2{\mathrm{O}}_2$-induced oxidative stress. Transcriptomic profiling of the biotransformation process identified 2221 differentially expressed genes (DEGs), showing significant enrichment in cytochrome P450-mediated metabolism and oxidative stress response pathways, which were further validated by qPCR. These results establish G. lingzhi as an efficient biocatalyst for the structural modification of tanshinones and provide a library of novel DHT derivatives for drug discovery. Full article

As a devastating disease worldwide, rice bacterial leaf blight—caused by Xanthomonas oryzae pv. oryzae (Xoo)—leads to substantial reductions in grain yield. The increasing resistance to conventional bactericides necessitates the development of novel and sustainable control agents. This study evaluated 58 novel alkyl sulfonamide compounds against Xoo. In the turbidimetric assay at 100 mg/L, several compounds showed potent antibacterial activity. Among them, SYAUP-116 and SYAUP-212 exhibited in vitro inhibition comparable to that of streptomycin sulfate at the same concentration. Furthermore, in EC₅₀ determination assays, both compounds yielded lower EC₅₀ values than zinc thiazole. Among the 58 compounds tested, SYAUP-491 exhibited an in vitro EC₅₀ of 6.96 mg/L and achieved 74.1% in vivo therapeutic efficacy at 200 mg/L, representing the most promising lead for further characterization. Molecular docking, based on prior proteomic data, indicates potential stable binding to ribosomal proteins (50S L33/L34 and 30S S5), with the strongest interaction observed for L33 (binding free energy: −5.73 kcal/mol). This suggests a putative mechanism involving ribosome targeting and protein synthesis inhibition, which may be facilitated by hydrophobic interactions and halogen bonds derived from its trifluoromethyl and sulfonamide groups. SYAUP-491 demonstrates significant potential as a novel bactericide for rice bacterial leaf blight, warranting further research on structure-activity optimization, target validation, and field performance. Full article

The worldwide rise in antimicrobial resistance, along with the ongoing prevalence of cancer, underscores the pressing need for novel, safe, and multifunctional therapeutic candidates. Medicinal plants continue to serve as a valuable source of chemically diverse bioactive molecules that modulate multiple biological targets. In this investigation, the preliminary screening of the antibacterial and anticancer activities of an ethanolic extract of Alhagi maurorum (A. maurorum) was comprehensively evaluated using integrated chemical characterization, in vitro bioassays, and in silico approaches. A liquid chromatography–mass spectrometry (LC-MS) analysis demonstrated a rich phytochemical profile including glucosinolates, phenolic acids, gallotannins, fatty acids, alkaloids, carotenoid derivatives, and 2-hexyldecanoic acid-associated constituents. Antibacterial efficacy was assessed by disk diffusion and minimum inhibitory concentration (MIC) testing against Escherichia coli (E. coli) and Bacillus cereus (B. cereus), with the extract producing inhibition zones similar to those observed with streptomycin. Anticancer effects were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays with MCF-7 breast carcinoma cells and Hs27 normal fibroblasts over 24, 48, and 72 h, revealing a time-dependent, selective decrease in malignant cell viability with relatively limited toxicity towards normal cells. Induction of apoptosis was further verified by propidium iodide (PI) staining. A molecular docking analysis highlighted 2-hexyldecanoic acid as the principal active compound, with a strong binding affinity for critical bacterial targets (GyrA, GyrB, and RpoB). In silico toxicity and ADME (absorption, distribution, metabolism, and excretion) assessments indicated favorable drug-like properties, good gastrointestinal uptake, and acceptable safety profiles. Altogether, these results provide combined experimental and computational support for A. maurorum as a promising source of dual-purpose antibacterial and anticancer agents and lay a mechanistic foundation for subsequent preclinical studies. Full article

The growing environmental plastic pollution triggered research for biodegradable and safe materials, among which biopolymer-based films stand as the most promising. Among these, chitosan has gained significant attention due to its biocompatibility, film-forming ability, and inherent antimicrobial properties. In this context, the use of fillers to design chitosan nanocomposite films has been shown to enhance the mechanical, barrier, thermal, optical, and antimicrobial properties of the resulting bioplastics. However, the fate and destiny of these fillers, as well as their impact on the biological properties and biodegradability of chitosan films, remain underexplored. We herein report a more comprehensive screening of a set of fillers, encompassing three clay variants (montmorillonite, sepiolite, and halloysite) and microcrystalline chitin. The films were systematically characterized to assess their antibacterial performance, cytocompatibility, hemocompatibility, and biodegradability. The highest antibacterial activity was observed for CS@MMT-f film towards Staphylococcus aureus and Escherichia coli. Importantly, all developed films demonstrated negligible hemolytic activity and low cytotoxicity, indicating their safety for potential biomedical or food-contact applications. Moreover, the selected films completely degrade within four to six weeks under soil burial conditions, demonstrating their potential as environmentally friendly packaging materials. Full article