Mostafa-Hedeab Gomaa, Hegazy Akram, Mostafa Islam, Eissa Ibrahim H, Metwaly Ahmed M, Elhady Hany Abdelfattah, Eledrdery Abozer Y, Alruwaili Sager Holyl, Alibrahim Alaa Oqalaa E, Alenazy Fawaz O, Alruwaili Muhannad Faleh Alanazi, Marghel Thamer Alshami, Alruwaili Muharib, Saad Alaaeldin Mohamed, Bayoumi Mahmoud, El-Shazly Assem Mohamed, Martinez-Sobrido Luis, Mostafa Ahmed
Pharmacology Department and Health Research Unit, Medical College, Jouf University, Skaka, 11564, Saudi Arabia.
Department of Agricultural Microbiology, Faculty of Agriculture, Cairo University, Giza district 12613, Giza, Egypt.
Sci Rep. 2025 Jul 2;15(1):22587. doi: 10.1038/s41598-025-06967-x.
Emerging and re-emerging respiratory viruses represent a continuing threat to human health. The pandemic severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and influenza A viruses (IAVs) are co-circulating, presenting serious threats to public health. Therefore, screening for safe and broad-spectrum antiviral candidates to control such viral infections is prioritized. Herein, this study reports the in vitro antiviral activity of some essential volatile oils (EOs) and volatile oil components including Peppermint oil, Eucalyptus oil, Clove oil, Thymol, Camphor and Limonin against two different IAVs, namely influenza A/H1N1 and A/H5N1 viruses, and SARS-CoV-2 virus. All tested samples were safe in MDCK and Vero E6 cell lines with CC values that exceed 1 mg/ml, allowing the screening of their antiviral activities using a wide range of concentrations. The results show the potency of Thymol and Limonin against influenza A/H1N1 virus with IC values of 0.022 and 4.25 µg/ml, respectively. The anti-influenza activities of Thymol and Limonin were further validated by testing them against the avian influenza A/H5N1 virus, resulting in anti-influenza activities with IC values of 18.5 and 15.6 ng/ml, respectively. The broad-spectrum potential of the highly potent antiviral candidates, Thymol and Limonin, were further tested against the pandemic SARS-CoV-2 and, both exerted anti-coronavirus activities with IC values of 0.591 and 4.04 µg/ml, respectively. Further investigations against influenza A/H1N1 virus revealed that Thymol and Limonin could inhibit IAV by hindering viral replication. The Biochemical analyses of the interaction of Limonin and Thymol with FDA-approved anti-influenza drug targets, neuraminidase and viral polymerases, revealed that both compounds can partially inhibit IAV polymerase activity, but have no effect on neuraminidase activity. Likely, molecular docking studies indicated that Thymol and Limonin obstruct active binding sites of IAV polymerases. These findings presented on the antiviral activity of Limonin and Thymol might be used to support the development of supplemental therapy against currently emerging and reemerging respiratory viral infections.
新出现和再次出现的呼吸道病毒持续威胁着人类健康。大流行的严重急性呼吸综合征冠状病毒2（SARS-CoV-2）和甲型流感病毒（IAV）共同传播，对公众健康构成严重威胁。因此，筛选安全且具有广谱抗病毒活性的候选药物以控制此类病毒感染成为当务之急。在此，本研究报告了一些重要挥发油（EO）及其成分，包括薄荷油、桉叶油、丁香油、百里香酚、樟脑和柠檬苦素，对两种不同的IAV（甲型流感病毒H1N1和H5N1）以及SARS-CoV-2病毒的体外抗病毒活性。所有测试样品在MDCK和Vero E6细胞系中均安全，其半数细胞毒性浓度（CC值）超过1mg/ml，从而能够在较宽浓度范围内筛选其抗病毒活性。结果表明，百里香酚和柠檬苦素对甲型流感病毒H1N1具有抗病毒活性，其半数抑制浓度（IC值）分别为0.022和4.25μg/ml。通过对其针对禽流感病毒H5N1进行测试，进一步验证了百里香酚和柠檬苦素的抗流感活性，其IC值分别为18.5和15.6ng/ml。针对高效抗病毒候选物百里香酚和柠檬苦素的广谱抗病毒潜力，进一步测试了它们对大流行的SARS-CoV-2的活性，二者均表现出抗冠状病毒活性，IC值分别为0.591和4.04μg/ml。针对甲型流感病毒H1N1的进一步研究表明，百里香酚和柠檬苦素可通过阻碍病毒复制来抑制IAV。对柠檬苦素和百里香酚与美国食品药品监督管理局（FDA）批准的抗流感药物靶点神经氨酸酶和病毒聚合酶相互作用的生化分析表明，这两种化合物均可部分抑制IAV聚合酶活性，但对神经氨酸酶活性无影响。分子对接研究表明，百里香酚和柠檬苦素可阻碍IAV聚合酶的活性结合位点。这些关于柠檬苦素和百里香酚抗病毒活性的研究结果，可能有助于支持针对当前新出现和再次出现的呼吸道病毒感染的补充疗法的开发。
