The global burden of COVID-19 continues to rise, and despite significant progress in vaccine development, there remains a critical need for effective treatments for the severe inflammation and acute lung injury associated with SARS-CoV-2 infection. In this study, we explored the antiviral properties of a plant-derived complex consisting of flavonol and hydroxyorganic acid compounds. Our research focused on the ability of the flavonol and hydroxyorganic acid complex to suppress the activity of several key proteins involved in the replication and maturation of SARS-CoV-2. These proteins include ACE2 protein, HRV 3C Protease, and Mpro (Main Protease). It was shown that the plant-based complex effectively inhibited the activity of these viral proteins. In addition to its effects on viral proteins, the flavonol and hydroxyorganic acid complex were shown to suppress viral replication in Vero E6 cells. At a dose of 22 μg/mL, the drug demonstrated maximum antiviral activity, significantly reducing the replication of SARS-CoV-2 in vitro. In preliminary studies, the complex showed both prophylactic and therapeutic potential, suggesting that it may be useful for preventing infection, as well as reducing the severity of disease once an individual has been infected with SARS-CoV-2. Based on the compelling results of this study, we propose the flavonol and hydroxyorganic acid complex as a potential therapeutic compound for SARS-CoV-2. Its ability to inhibit key viral proteins, suppress viral replication and exhibit protective and therapeutic effects positions it as a valuable candidate for further research and clinical evaluation. As the global fight against SARS-CoV-2 continues, plant-based therapies like this complex could complement existing treatments and provide new options for managing and treating the disease.

The use of vaccines incorporating subunit proteins and viral components has significantly increased in recent decades, emphasizing the need for more effective and modular adjuvants. This study examined saponins from Saponaria officinalis, regarded as one of the most promising plant sources for developing an adjuvant platform using nanocomplex formation. A nanoparticle adjuvant containing saponins from Saponaria officinalis can be used to stimulate a humoral immune response; this ability was demonstrated using a model that included various viral proteins. The humoral immune response enhanced by saponin-containing adjuvants can increase from four to sixteen times, depending on the type of antigen used. Additionally, this response surpasses that triggered by antigens paired with aluminum hydroxide and is comparable to responses induced by adjuvants that contain Quil A. The further investigation of these platforms may yield a broader range of immunostimulants that can enhance vaccine effectiveness.

Разнообразие вариантов вируса инфекционного бронхита птиц создает определенные трудности при вакцинации. Поэтому поиск новых методов подавления репродукции вируса является важной проблемой в птицеводстве. Вирус инфекционного бронхита птиц это острое высококонтагиозное вирусное заболевание, преимущественно цыплят, сопровождающееся поражением органов дыхания у молодняка и потерей продуктивности у взрослых кур-несушек. Поиск лекарственных средств, которые способны подавлять активность вирусов дает возможность искать таковые среди лекарственных растении. Использование лекарственных растений является важной темой как для фармацевтики, так и для медицины в целом. Многие вирусы выработали устойчивость к существующим препаратам, поэтому имеет смысл изучать растения, которые содержат биологически активные соединения, способные подавлять вирусную активность. Благодаря большому количеству активных соединении, Alnus incana, Hedysarum neglectum, Polygonum aviculare и Alhagi pseudalhagi являются перспективными растениями для создания противовирусных препаратов. Цель исследования - показать возможность использования экстрактов некоторых растений для подавления репродукции вируса инфекционного бронхита птиц. Показано, что в дозе от 3 до 4 мкг/мл растительные экстракты серой ольхи, красного корня, горца птичьего и верблюжьей колючки способны на 50 % подавлять репродуктивную активность вируса инфекционного бронхита птиц.

The increasing use of subunit and recombinant vaccines has created a demand for safe and effective adjuvants capable of enhancing immune responses. Here, we investigated a saponin-rich fraction isolated from Herniaria glabra as a source of novel nanoparticulate vaccine adjuvants. The saponins spontaneously self-assembled with lipid components to form stable nanocomplexes with favorable physicochemical characteristics. In a murine immunization model using viral glycoprotein antigens, these nanocomplexes significantly enhanced antigen-specific immune responses, increasing antibody titers by 8- to 16-fold compared with antigen alone. Their adjuvant activity exceeded that of aluminum hydroxide and approached that of Quillaja saponaria-derived saponin formulations. The nanocomplexes also induced balanced cellular immune responses comparable to those reported for Quil A-based nanosystems. These findings identify H. glabra as a promising alternative source of bioactive saponins and demonstrate the potential of plant-derived nanocomplexes as versatile adjuvant platforms for next-generation vaccines.

Roseofungin, a polyene macrolide antibiotic produced by Streptomyces roseoflavus, was evaluated for antiviral activity against Influenza A virus using complementary in vitro, in ovo, and preliminary in vivo toxicity models, supported by molecular docking and molecular dynamics simulations. The compound exhibited antiviral activity against multiple influenza A virus subtypes, including an oseltamivir-resistant H1N1 strain, with EC₅₀ values ranging from 2.0 to 2.5 μg/mL and selectivity indices of 20–25. Functional assays demonstrated that roseofungin interfered with early stages of the viral life cycle by reducing viral adsorption and partially inhibiting neuraminidase activity. In virucidal assays, treatment with roseofungin resulted in a 1.5–2.5 log₁₀ reduction in infectious viral titers. Acute toxicity studies in mice indicated low toxicity under the experimental conditions (LD₅₀ > 25 mg/kg). Molecular docking predicted favorable interactions of roseofungin with multiple influenza A virus proteins. Subsequent molecular dynamics simulations of the hemagglutinin–roseofungin complex maintained the stability of the predicted binding mode across three independent 50 ns simulations (150 ns cumulative). Collectively, these findings demonstrate that roseofungin possesses broad-spectrum antiviral activity against genetically diverse Influenza A virus strains and represents a promising lead compound for the development of novel membrane-active antiviral agents. Further studies are warranted to elucidate its molecular mechanism of action and to evaluate its therapeutic potential in vivo.