Search Results (86)

Mayaro virus (MAYV) is an arthritogenic alphavirus transmitted by mosquitoes and is the causative agent of Mayaro fever. This disease is associated with symptoms such as arthralgia and myalgia, which may persist for months or even years. Currently, no vaccine or specific antiviral therapy is available. This study aimed to assess the antiviral activity of synthetic imine-chalcone derivatives (1a–1d) against MAYV replication in Vero cells and predict their pharmacokinetic and toxicological properties. All compounds presented low cytotoxicity, with CC₅₀ values ranging from 249.92 µM to >1000 µM. Additionally, the derivatives showed good antiviral activity, with compound 1a being the most potent (EC₅₀ = 12.15 μM; SI = 31.47), and 1b being the most selective (EC₅₀ = 16.92 μM; SI > 59.10). Mechanistic assays revealed that compounds 1a and 1b primarily inhibit early events in the MAYV life cycle, such as viral adsorption (1a: 51.53%; 1b: 59.35%) and entry (1a: 71.26%; 1b: 54.21%). Compound 1b also impaired virus egress, while none of the compounds exhibited strong virucidal activity. Finally, in silico ADMET predictions suggested favorable pharmacokinetic and toxicological parameters for compounds 1a and 1b. Overall, our work demonstrated for the first time the activity and safety of imine-chalcones against MAYV. Full article

The research investigates synthetic hydroxytyrosol (HT) antiviral properties against enveloped and non-enveloped viruses using in silico and in vitro methods. Molecular docking and ADMET analyses suggested favorable interactions of HT with ceramide and sphingomyelin (binding energies of −6.0 and −5.9 kcal/mol, respectively). Favorable predicted pharmacokinetics and safety profiles were also observed. In vitro tests provided preliminary evidence of the dose- and time-dependent virucidal effect of HT against several enveloped viruses, including HSV-1, West Nile virus, SARS-CoV-2 and various influenza A subtypes, which resulted in substantial viral load decreases at 1000 µg/mL. The viral titer of the measles virus decreased by 4.62 log₁₀ units during the 2 h of exposure. No virucidal activity was observed against the non-enveloped bovine rotavirus. Overall, these findings suggest that hydroxytyrosol may represent a promising candidate for further investigation as a virucidal agent, particularly against enveloped viruses. Full article

Despite increased interest in virus survival on surfaces, data on bovine herpesvirus type 1 (BoHV-1) interactions with metal surfaces remain limited. This study aimed to assess the effects of copper, zinc, and iron on BoHV-1 viability, viral titre, and DNA stability under different conditions. MDBK-adapted BoHV-1 was used to investigate the virucidal effect of copper, zinc and stainless steel surfaces. The virus was exposed for 1 and 24 h under both wet and dry conditions. Inactivation was assessed based on changes in TCID₅₀ log₁₀ values, qPCR Ct results, and calculating half-lives of the virus and its DNA. Virus stability varied depending on surface type, environmental conditions, and duration of exposure. Copper demonstrated the strongest virucidal effect, significantly reducing viral titres and DNA levels under all conditions. After 1 h in wet conditions, copper reduced viral titre to 4.7 log₁₀, while zinc and stainless steel showed minimal impact. Under dry conditions, copper reduced viral titres to the limit of detection after 24 h. Half-life analysis confirmed rapid inactivation on copper, with the shortest persistence observed across all conditions. Zinc showed moderate virucidal activity but required longer exposure times. These findings highlight copper’s superior antiviral properties and suggest its potential application in reducing viral transmission on surfaces. Full article

Infectious diseases remain a major global health challenge, underscoring the need for safe and accessible antiviral therapies. Natural products, particularly marine macroalgae, are promising sources of bioactive compounds with antiviral properties. This study evaluated the antiviral activity of extracts from two red algae collected along the Portuguese coast: two life stages (tetrasporophyte and female gametophyte) of Chondracanthus teedei var. lusitanicus and the algae Osmundea pinnatifida. Antiviral effects were assessed against Coxsackievirus A12 (CVA12) and a lentivirus (LV) vector model. Extracts from both algae inhibited viral replication in vitro at non-cytotoxic concentrations. The tetrasporophyte extract of C. teedei exhibited virucidal activity against CVA12, and the results are consistent with interference with multiple stages of the viral life cycle, while also inducing an antiviral state in HEK-293T cells against LV infection. The female gametophyte extract affected early stages of CVA12 and LV infection and showed potential virucidal activity. O. pinnatifida demonstrated the strongest antiviral effects against both viruses. These findings highlight the antiviral potential of these red algal extracts and warrant further in vivo evaluation. Full article

The ongoing emergence of antiviral drug resistance underscores the critical need for new broad-spectrum antiviral agents. Sulfonamides and their derivatives have emerged as promising candidates for the development of new antiviral therapeutics. In this study, a series of camphor-10-sulfonamide derivatives was synthesized through a feasible and sustainable synthetic approach starting from naturally available precursors and evaluated for antiviral properties. Their activity was examined against three structurally distinct viruses—herpes simplex virus type 1 (HSV-1), human coronavirus (HCoV-OC43), and feline calicivirus (FCV)—representing both DNA and RNA, enveloped and non-enveloped types. The compounds were examined for their effects on viral replication, the stage of viral adsorption to the cell, and extracellular virions. The weakest cytotoxicity and the most pronounced activity of all the tested substances was demonstrated by the tryptophan derivative 7a. A time-dependent inhibition of the stage of adsorption of HCoV-OC43 (Δlg = 2.0 at 120 min) and FCV (Δlg = 1.75 at 60 min) to susceptible cells was established, as well as virucidal activity on the three types of virions tested, with the most pronounced effect at 120 min—for HSV-1 (Δlg = 2.75) and Δlg = 2.0 for HCoV-OC43 and FCV. Molecular docking studies performed using Glide (Schrödinger) provided insights into the active conformations of the most effective ligands and predicted possible interactions with relevant viral targets, supporting their potential as lead structures for further therapeutic development. Full article

Zinc oxide nanoparticles (ZnO NPs) have attracted growing interest in several fields, including topical biomedical applications, due to their stability, biocompatibility and therapeutic potential. In this study, chitosan (Ch), gelatin (G) and arabic gum (AG) were combined to formulate hydrogels loaded with different ZnO NP concentrations. The main aim is to assess the synergy between the properties of biopolymers and ZnO moieties in terms of antiviral activity. ZnO NPs were synthesized via co-precipitation. Hydrogels were prepared using the freeze–thaw method, and the loading of 2.5, 5 and 7.5% w/w of ZnO NPs with respect to Ch was promoted by ultrasonication. The structural, morphological, surface and thermal properties of hydrogels loaded with ZnO NPs (HZ 2.5, HZ 5 and HZ 7.5) and the control matrix (H) were characterized using FTIR spectroscopy, confirming the successful incorporation and interaction of ZnO NPs with the polymeric network. Low ZnO NP concentrations enhanced the swelling degree of the hydrogels (from 1044% to 1253%), improving their thermal stability and solubility (96 h vs. 48 h HZ 7.5 and 14 h in the case of H). This behavior could be ascribed to the aggregation of ZnO NPs with increasing amounts, which was verified through FESEM. Virucidal activity was tested against herpes simplex virus type 1 (HSV-1) and bovine coronavirus (BCoV), demonstrating a substantial enhancement when the ZnO NPs are added independently of the concentration. An almost 100% viral inhibition was recorded when the HZs were analyzed, whereas the H matrix showed an inhibition of about 40% against the same virus. Antioxidant activity was evaluated via the DPPH free radical inhibition method, revealing an improvement with the loading of NPs. Full article

The escalating global crisis of antimicrobial-resistant (AMR) bacterial infections, along with the continuous threat of viral outbreaks, poses a serious risk to public health worldwide and underscores the urgent need for innovative therapeutic strategies. In this study, mesoporous silica nanoparticles (MSNs) were successfully synthesized and subsequently functionalized with copper to impart broad-spectrum antimicrobial activity. The oxidation state of copper on the MSN surface was modulated through thermal treatments, allowing the evaluation of its influence on antimicrobial efficacy. The modified MSNs were tested against key bacterial pathogens, including Escherichia coli and Staphylococcus aureus, achieving complete bactericidal activity after 2 h of exposure to E. coli. Moreover, as well as influenza A (H1N1) pdm09, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and MS2 bacteriophage (MS2) were evaluated, reaching an efficiency higher than 80%, 90%, and 97%, respectively. The results indicated that copper-modified MSNs exhibit potent antibacterial and antiviral activity, highlighting their potential as an antibiotic-free alternative for preventing microbial infections while mitigating the development of AMR bacteria. Full article

The study focused on essential oils (EOs) of plant origin, which are of great interest to scientists in the context of medical applications due to their biological properties, such as antimicrobial, anti-inflammatory, antioxidant, and anticancer effects. The objective of the study was to determine chemical profiles and biological activities of the essential oils extracted from five mixtures (M1 [Thymus vulgaris, Ammi visnaga, Syzygium aromaticum, Citrus sinensis]; M2 [Thymus vulgaris, Ammi visnaga, Cinnamomum verum, Citrus sinensis]; M3 [Mentha pulegium, Lavandula angustifolia, Zingiber officinale, Citrus sinensis]; M4 [Mentha pulegium, Lavandula angustifolia, Cinnamomum verum, Citrus sinensis]; M5 [Ammi visnaga, Lavandula angustifolia, Zingiber officinale, Syzygium aromaticum]). Each mixture was derived from a blend of four selected plants used in traditional medicine in Mostaganem, Algeria. When selecting the best composition, the interactions between plant components were considered in terms of potential therapeutic benefits. The chemical compositions of the EO mixtures were analyzed using GC-MS. The acute toxicity of the EO mixtures was evaluated in vivo following oral administration. The sensitivity of the microorganisms to the EO mixtures was determined using the agar diffusion method. Virucidal testing was performed using the quantitative suspension method to determine virucidal activity, as described in the European standard for disinfectants used in the medical field. The antioxidant activity of the EO mixtures was evaluated using a model membrane system based on liposomes derived from soybean phosphatidylcholine. Chemopreventive activity was assessed in vitro using cell culture. The main compounds identified were carvacrol and thymol in M1; geranial, cinnamylaldehyde, and carvacrol in M2; pulegone and limonene in M3; geranial and cinnamylaldehyde and limonene in M4; and eugenol and caryophyllene in M5. The selection of the “best” blend depended on the biological activity deemed most critical for the specific application. Specifically, M3, M4, and M5 exhibited the strongest anti-HSV-1, anti-HAdV-5, and anticancer activity, respectively. In contrast, M1, a potent antioxidant, demonstrated the strongest antibacterial and anticancer activity. These results indicate that M1, M3, M4, and M5 EOs have promising applications in the pharmaceutical industry and medical research. Full article

The poultry industry is continually seeking efficient, practical strategies to control infectious diseases. Among these new alternatives are essential oils (EOs), naturally occurring compounds with antimicrobial properties. Their effectiveness has been demonstrated in various studies that focus on their broad antiviral properties. The present experiment evaluated the antiviral efficacy of an EOs formulation against the H7N3 subtype of avian influenza virus (AIV) by directly mixing virus and EOs (virus/EOs mixture) through an in vitro model in cultured Madin-Darby canine kidney cells (MDCKs). The experiment used a focus reduction neutralization test (FRNT) to determine the 50% inhibitory concentration (IC₅₀) by virus/EOs mixture, as well as the application of EOs 24 h before infection, through a viral inhibition test using a chicken embryo (CE) in ovo model. The results demonstrated the antiviral activity of the EOs formulation against the H7N3 in vitro model (IC₅₀ values of 20.4 and 38.3 ppm and selective index (SI) values of 9.4 and 5.1) and in ovo model (decreasing hemagglutination titers to 1 HA unit, 10^5.28 embryo infectious dose 50% (EID₅₀) per mL, and viral loads to approximately 10^11.4 copies/mL) when applied in CE, 24 h before viral infection, representing the lowest replication indicators recorded during the experiment. According to the results, the EOs formulation demonstrated antiviral activity against AIV H7N3 both as a virus/EOs mixture and through application in ovo 24 h before infection. Application 24 h before infection in CE showed a significant effect compared with the virus/EOs mixture, demonstrating an antiviral effect in the ovo infection model. This study demonstrates both the virucidal and antiviral capacity of the compounds in the EOs formulation against AIV H7N3 and their efficacy when applied 24 h before infection in the in ovo model. Full article

The transmission of viruses and bacteria via surfaces remains a persistent challenge for healthcare systems, leading to high public health costs and significant environmental impact due to the widespread use and disposal of single-use products. This study aims to evaluate the feasibility of using surface-covering films, based on biopolymers and inorganic nanoparticles, with strong antiviral and antibacterial properties, as a strategy to prevent infection transmission while offering a sustainable alternative to disposable materials. To this end, we developed a sprayable chitosan-based solution embedded with copper oxide nanoparticles (CH.CA@Cu). The solution demonstrated antibacterial activity against both Gram-positive and Gram-negative bacteria as well as virucidal activity, predominantly within one minute of exposure, against a wide range of viruses. After spraying various materials, the resulting film surfaces exhibited excellent adherence and uniform coverage, maintaining their integrity after contact. A field trial conducted in high-traffic environments confirmed the coating’s effectiveness. This long-lasting antiviral action supports their implementation, since the coated surface can continuously deactivate viruses regardless of infective doses of exposure, thereby reducing viral transmission. These findings will expand biopolymers’ current applicability while guiding us toward the adoption of green and eco-friendly technologies, thus reducing waste production. Full article

Norovirus (NoV) is a symptomatic virus that is the leading cause of gastrointestinal disease. It spreads easily through the fecal–oral route and contact with contaminated food or surfaces. Maintaining a high level of hygiene in food industry settings and refocusing food production on isolating and testing natural compounds that exhibit antimicrobial and antioxidant properties are important elements in preventing NoVs infection. This study evaluated plant extracts prepared by cold brew and cold concentrate techniques for their antioxidant and antiviral activity. The extracts obtained demonstrated high antioxidant activity, with notable variation depending on the plant material, ranging from moderate to very strong levels. Correspondingly, high antiviral potential was observed, reaching the nearly complete inactivation of the virus. Remarkably, the highest virucidal effects were already achieved at relatively elevated, but not maximal, antioxidant activity levels. The results of the study indicate that cold water extraction techniques allow for the obtention of plant extracts showing strong virus-inactivating activity and favorable antioxidant activity. Full article

Glass ionomers are utilized extensively within the domain of dentistry, for instance, as provisional restorations, liners, or bases, in addition to their application as pit and fissure sealers. It is imperative that this type of material exhibits favorable physico-chemical and biological properties. The primary objective of the presented study is to modify commercial resin-modified glass ionomer (Riva Light Cure, RMGIC) by doping it with copper particles (RMGIC + Cu) and to evaluate its properties in terms of potential beneficial clinical applications. Susceptibility to adhesion of microbial species and potential antimicrobial activity was evaluated against the Candida albicans, Streptococcus mutans, and Lactobacillus rhamnosus strains. Antiviral properties were evaluated against two viruses: Herpes simplex virus type 1 and human Adenovirus 5. Cytotoxicity of the materials was assessed using Balb/3T3 mouse fibroblast cell line. Temporal fluoride release up to 168 h in water and artificial saliva of different pH levels were also measured and assessed using statistical analysis. Samples were also subjected to Attenuated Total Reflectance Fourier-Transform Infrared Spectroscopy and Fourier-Transform Raman Spectroscopy. The findings of the present study demonstrate that RMGIC + Cu displays reduced biofilm formation against the tested strains when compared to non-modified material. The influence of the Cu presence on fluoride release is most pronounced in artificial saliva with a low pH (4.5), where the difference is significantly higher in samples with Cu than in samples without it. No reduction in herpes simplex 1 titers under the influence of either material was observed, whereas both materials exhibited virucidal properties against human adenovirus 5. Commercial glass ionomer presented no cytotoxicity, while the modified biomaterial caused changes in the fibroblast culture only under the sample (slight cytotoxicity, grade 1). Considering all the acquired results, doping glass ionomer with copper may be an interesting modification enhancing antimicrobial properties of the biomaterial, but it requires further evaluation in terms of long-term cytotoxicity before further in vivo studies. Full article

Sourcing and batch differences are often cited as intrinsic drawbacks for all natural polymers. Chitosan makes no exception. Chitosan is a biocompatible and biodegradable biopolymer with high potential for several biomedical applications, especially for releasing drugs and bactericidal and virucidal agents. Despite the potential of chitosan as a matrix for producing antibacterial films, the variability in its composition, stemming from its natural sources, can hinder the translation from bench to industry. To overcome this concern, we conducted a study to access the interchangeability of chitosan for the development of antibacterial drug release systems, in particular one system crosslinked with tannic acid and iron sulfate. Chitosans from different suppliers were characterized and used to synthetize films containing gentamicin, according to a previously reported protocol. The impact of molecular weight (M_W), deacetylation degree and purity on film properties and antibiotic release kinetics was assessed and results were compared. The films exhibited different initial bursts followed by similar sustained release profiles. All films exhibited antibacterial activity against both E. coli and S. aureus for at least 42 days. Moreover, films were cyto- and hemocompatible. Therefore, despite some differences in physicochemical properties, the interchangeability among the studied chitosan suppliers to produce antibacterial films is feasible, and the final product properties and performances are not significantly altered. Full article

The rising incidence of oropharyngeal cancer caused by high-risk Human Papillomavirus (HPV) type 16 and HPV18 in the U.S and other developed countries is an important public health issue. This has been attributed to changes in sexual behavior, including the practice of oral sex, which may expose individuals to increased risk of acquiring oral HPV infection. The incidence of oral HPV infections highlights the role of the oral cavity as an important anatomical site in the acquisition and transmission of high-risk HPVs. Generally, the use of mouthwash/oral rinses have focused on targeting the oral bacteriome, and could additionally be formulated for managing the oral virome. Here, we examined virucidal properties of common over-the-counter antibacterial mouthwash products against native HPV16 and HPV18 virion in vitro, and downstream modification of virus infectivity. We tested oral rinses containing essential oils/alcohol, hydrogen peroxide, and cetylpyridinium chloride. Our results demonstrated greater than 90% efficacy against HPV16 inactivation, but comparatively with less efficacy against HPV18. Overall, hydrogen peroxide containing oral rinses demonstrated the best efficacy against both high-risk types, albeit with lower efficacy against HPV18. Prophylactic virucidal oral rinses targeted towards high-risk HPVs could be beneficial in reducing incidental oral HPV load, prevalence, and persistent infections. Full article

Background/Objectives: This study aims to gain insights into the antimicrobial and antiherpetic activity of hyperforin-rich Hypericum perforatum L. (HP) extract using nanostructured lipid carriers (NLCs) as delivery platforms. Methods: Two established NLC specimens, comprising glyceryl behenate and almond oil or borage oil, and their extract-loaded counterparts (HP-NLCs) were utilized. Their minimal bactericidal/fungicidal concentrations (MBC; MFC) were investigated against Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 10145, Klebsiella pneumoniae ATCC 10031, and Candida albicans ATCC 10231. The anti-herpesvirus (HSV-1) potential was evaluated concerning antiviral and virucidal activity and impact on viral adsorption. Results: The borage oil-based extract-loaded nanodispersion (HP-NLC2) exhibited pronounced microbicidal activity against S. aureus (MBC 6.3 mg/mL), K. pneumoniae (MBC 97.7 µg/mL), and C. albicans (MFC < 48.8 µg/mL), unlike the almond oil-containing sample (HP-NLC1), which showed only weak inhibition of the fungal growth. HP-NLC2 was found to be less cytotoxic and to suppress HSV-1 replication slightly more than HP-NLC1, but generally, the effects were weak. Neither the empty lipid nanoparticles nor the HP extract-loaded carriers expressed activity against E. coli, P. aeruginosa, the HSV-1 extracellular virions, or viral adhesion. Conclusions: It could be concluded that both HP-NLC samples revealed only minor antiherpetic potential of the hyperforin-rich extract, but HP-NLC2 demonstrated significant antibacterial and antimycotic activity. Therefore, the latter was featured as a more convenient HP-carrier system for nano-designed dermal pharmaceutical formulations. Such a thorough investigation of hyperforin-determined anti-HSV-1 effects and antibacterial and antimycotic properties, being the first of its kind, contributes to the fundamental knowledge of HP and reveals new perspectives for the utilization, limitations, and therapeutic designation of its non-polar components. Full article