Joint Faculty of Veterinary Medicine, Transboundary Animal Diseases Research Center, Kagoshima University, Kagoshima 890-0065, Japan.
Joint Graduate School of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065 , Japan.
Lett Appl Microbiol. 2023 Feb 16;76(2). doi: 10.1093/lambio/ovac053.
Tannins derived from natural plant sources are known to provide many health benefits to humans and animals. Among the various tannins, those derived from persimmon (Diospyros kaki) have exhibited strong inactivating effects against pathogens that induce diseases in humans. However, few studies have focused on the antiviral effects of persimmon tannin against pathogen-induced diseases in animals. In this study, we investigated the antiviral effects of persimmon tannin against various avian influenza viruses revealing that tannin at a concentration of 1.0 mg ml-1 reduced viral infectivity in >6.0-log scale against all tested avian influenza viruses. In addition, this persimmon tannin concentration effectively inhibited the receptor binding and membrane fusion abilities of viral hemagglutinin (HA), which play important roles in avian influenza virus infection. These results suggest that persimmon tannin inactivates the HA of avian influenza viruses and reduces their infectivity. Persimmon tannin is a safer natural substance than the currently used chemical compound related to antiviral substance. When inactivation of the viruses which are present in environmental water such as roosting water of wild birds will be needed, persimmon tannin is expected to become an antiviral resource that may prevent the spread of several avian influenza virus subtypes.
从天然植物来源中提取的单宁被认为对人类和动物有许多健康益处。在各种单宁中，柿子（Diospyros kaki）单宁对引起人类疾病的病原体具有很强的灭活作用。然而，很少有研究关注柿子单宁对动物病原体诱导疾病的抗病毒作用。在这项研究中，我们研究了柿子单宁对各种禽流感病毒的抗病毒作用，结果表明单宁在 1.0mg/ml 的浓度下，对所有测试的禽流感病毒的病毒感染力降低了>6.0 个对数级。此外，这种柿子单宁浓度能有效抑制病毒血凝素（HA）的受体结合和膜融合能力，这在禽流感病毒感染中起着重要作用。这些结果表明，柿子单宁使禽流感病毒的 HA 失活，降低了其感染力。柿子单宁是一种比目前使用的与抗病毒物质有关的化学化合物更安全的天然物质。当需要灭活环境水中存在的病毒时，如野生鸟类的栖息水，柿子单宁有望成为一种抗病毒资源，可能防止几种禽流感病毒亚型的传播。
