Lee Yun Ha, Jang Yo Han, Kim Young-Seok, Kim Jinku, Seong Baik Lin
Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, South Korea.
Department of Biological and Chemical Engineering, College of Science and Technology, Hongik University, Sejong, South Korea.
J Biol Eng. 2018 Jan 8;12:1. doi: 10.1186/s13036-017-0092-1. eCollection 2018.
Viral infections often pose tremendous public health concerns as well as economic burdens. Despite the availability of vaccines or antiviral drugs, personal hygiene is considered as effective means as the first-hand measure against viral infections. The green tea catechins, in particular, epigallocatechin-3-gallate (EGCG), are known to exert potent antiviral activity. In this study, we evaluated the green tea extract as a safe personal hygiene against viral infections.
Using the influenza virus A/Puerto Rico/8/34 (H1N1) as a model, we examined the duration of the viral inactivating activity of green tea extract (GTE) under prolonged storage at various temperature conditions. Even after the storage for 56 days at different temperatures, 0.1% GTE completely inactivated 10 PFU of the virus (6 log reduction), and 0.01% and 0.05% GTE resulted in 2 log reduction of the viral titers. When supplemented with 2% citric acid, 0.1% sodium benzoate, and 0.2% ascorbic acid as anti-oxidant, the inactivating activity of GTE was temporarily compromised during earlier times of storage. However, the antiviral activity of the GTE was steadily recovered up to similar levels with those of the same concentrations of GTE without the supplements, effectively prolonging the duration of the virucidal function over extended period. Cryo-EM and DLS analyses showed a slight increase in the overall size of virus particles by GTE treatment. The results suggest that the virucidal activity of GTE is mediated by oxidative crosslinking of catechins to the viral proteins and the change of physical properties of viral membranes.
The durability of antiviral effects of GTE was examined as solution type and powder types over extended periods at various temperature conditions using human influenza A/H1N1 virus. GTE with supplements demonstrated potent viral inactivating activity, resulting in greater than 4 log reduction of viral titers even after storage for up to two months at a wide range of temperatures. These data suggest that GTE-based antiviral agents could be formulated as a safe and environmentally friendly personal hygiene against viral infections.
病毒感染常常引发巨大的公共卫生问题以及经济负担。尽管有疫苗或抗病毒药物，但个人卫生被视为预防病毒感染的首要有效措施。尤其是绿茶儿茶素，特别是表没食子儿茶素-3-没食子酸酯（EGCG），已知具有强大的抗病毒活性。在本研究中，我们评估了绿茶提取物作为预防病毒感染的安全个人卫生用品。
以甲型流感病毒A/波多黎各/8/34（H1N1）为模型，我们研究了绿茶提取物（GTE）在不同温度条件下长期储存时病毒灭活活性的持续时间。即使在不同温度下储存56天后，0.1%的GTE仍能完全灭活10个PFU的病毒（6个对数级的减少），0.01%和0.05%的GTE导致病毒滴度降低2个对数级。当添加2%柠檬酸、0.1%苯甲酸钠和0.2%抗坏血酸作为抗氧化剂时，GTE的灭活活性在储存早期会暂时受到影响。然而，GTE的抗病毒活性会稳步恢复到与未添加补充剂的相同浓度GTE相似的水平，有效地延长了杀病毒功能的持续时间。冷冻电镜和动态光散射分析表明，GTE处理使病毒颗粒的整体尺寸略有增加。结果表明，GTE的杀病毒活性是由儿茶素与病毒蛋白的氧化交联以及病毒膜物理性质的改变介导的。
使用甲型流感病毒A/H1N1，在不同温度条件下对溶液型和粉末型GTE的抗病毒效果的耐久性进行了长期研究。添加补充剂的GTE表现出强大的病毒灭活活性，即使在广泛的温度范围内储存长达两个月后，病毒滴度仍降低超过4个对数级。这些数据表明，基于GTE的抗病毒剂可被配制成预防病毒感染的安全且环保的个人卫生用品。
