The annual spread of influenza A virus (IAV) infection is a global concern. We examined the IAV-inactivating potential of theaflavin-concentrated tea extract TY-1, which contains abundant polyphenols, including concentrated theaflavins and catechins. TY-1 exhibited concentration- and time-dependent virucidal activity against IAV. Specifically, 5.0 mg/mL TY-1 induced a 1.33 and ≥ 5.17 log₁₀ 50% tissue culture infective dose/mL reduction of the viral titer compared with dextrin as the diluent control within 30 min and 6 h reaction time, respectively. The high virucidal activity of TY-1 was attributed to the combined additive activities of multiple virucidal components, including theaflavins, which led to an investigation of the virucidal mechanism of action of TY-1. Western blotting revealed that TY-1 treatment reduced the band intensity of hemagglutinin and induced the appearance of additional high molecular mass bands/ladders. In addition, TY-1 treatment also reduced the band intensity of neuraminidase (NA). A hemagglutination assay revealed that TY-1 reduced hemagglutination activity, and an NA assay revealed reduced NA activity. These results indicated that TY-1 caused structural abnormalities in IAV spike proteins, possibly leading to their destruction. Reverse transcription polymerase chain reaction (PCR) targeting the IAV genome and electron microscopic observation of viral particles revealed that upon application of TY-1, the PCR products dissipated, which indicates that TY-1 destroyed the IAV genome, and the number of viral particles reduced. Overall, TY-1 exhibited multiple modes of IAV-inactivating activity. Our findings support the possible future practical use of TY-1 as a virucidal supplemental agent that can contribute to IAV infection control.

甲型流感病毒 (IAV) 感染的年度传播是全球关注的问题。我们检查了茶黄素浓缩茶提取物 TY-1 的 IAV 灭活潜力，它含有丰富的多酚，包括浓缩茶黄素和儿茶素。TY-1 表现出对 IAV 的浓度和时间依赖性杀病毒活性。具体而言，5.0 mg/mL TY-1 诱导 1.33 和 ≥ 5.17 log ₁₀与作为稀释剂对照的糊精相比，在 30 分钟和 6 小时反应时间内，病毒滴度分别降低 50% 的组织培养感染剂量/mL。TY-1 的高杀病毒活性归因于多种杀病毒成分（包括茶黄素）的组合加性活性，这导致了对 TY-1 杀病毒作用机制的研究。Western blotting 显示 TY-1 处理降低了血凝素的条带强度并诱导了额外的高分子量条带/阶梯的出现。此外，TY-1 处理还降低了神经氨酸酶 (NA) 的条带强度。血凝测定显示 TY-1 降低了血凝活性，NA 测定显示 NA 活性降低。这些结果表明 TY-1 导致 IAV 刺突蛋白的结构异常，可能导致他们的毁灭。针对 IAV 基因组的逆转录聚合酶链反应 (PCR) 和病毒颗粒的电镜观察显示，在应用 TY-1 后，PCR 产物消散，这表明 TY-1 破坏了 IAV 基因组，病毒颗粒的数量减少。总体而言，TY-1 表现出多种 IAV 灭活活动模式。我们的研究结果支持未来可能将 TY-1 作为一种有助于 IAV 感染控制的杀病毒补充剂实际使用。并且病毒颗粒的数量减少了。总体而言，TY-1 表现出多种 IAV 灭活活动模式。我们的研究结果支持未来可能将 TY-1 作为一种有助于 IAV 感染控制的杀病毒补充剂实际使用。并且病毒颗粒的数量减少了。总体而言，TY-1 表现出多种 IAV 灭活活动模式。我们的研究结果支持未来可能将 TY-1 作为一种有助于 IAV 感染控制的杀病毒补充剂实际使用。