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bioRxiv · 10.1101/2020.12.04.412098

Significant inactivation of SARS-CoV-2 by a green tea catechin, a catechin-derivative and galloylated theaflavins in vitro

Ohgitani, E.·Shin-Ya, M.·Ichitani, M.·Kobayashi, M.·Takihara, T.·Kawamoto, M.·Kinugasa, H.·Mazda, O.
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Abstract

Potential effects of teas and their constituents on SARS-CoV-2 infection were studied in vitro. Infectivity of SARS-CoV-2 was significantly reduced by a treatment with green tea, roasted green tea or oolong tea. Most remarkably, exposure to black tea for 1 min decreased virus titer to an undetectable level (less than 1/1,000 of untreated control). An addition of (-) epigallocatechin gallate (EGCG) significantly inactivated SARS-CoV-2, while theasinensin A (TSA) and galloylated theaflavins including theaflavin 3, 3-di-gallate (TFDG) had more remarkable anti-viral activities. Virus treated with TSA at 500 M or TFDG at 100 M showed less than 1/10,000 infectivity compared with untreated virus. TSA and TFDG significantly inhibited interaction between recombinant ACE2 and RGD of S protein. These results strongly suggest that EGCG, and more remarkably TSA and galloylated theaflavins, inactivate the novel coronavirus.

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Ohgitani, E., Shin-Ya, M., Ichitani, M., Kobayashi, M., Takihara, T., Kawamoto, M., Kinugasa, H., Mazda, O.. 2020-12-06. Significant inactivation of SARS-CoV-2 by a green tea catechin, a catechin-derivative and galloylated theaflavins in vitro. https://doi.org/10.1101/2020.12.04.412098

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