Inhibitory activity of tea compositions and their constituent ingredients on SARS‐COV‐2 replication in vitro

Abstract

Aim. In vitro analysis of the inhibitory activity of aqueous extracts of ready‐made tea compositions and their constituent ingredients on SARSCOV‐ 2 replication.Material and Methods. The laboratory strain SARS‐CoV‐ 2/human/RUS/Nsk‐FRCFTM‐1/2020 was passivated on Vero cell culture. For the preparation of water extracts six types of experimental tea compositions (not containing flavorings) based on black and green tea or flowers of hibiscus as well as individual ingredients were used. Antiviral (inhibitory) activity of plant raw materials was studied in vitro according to the classical scheme of neutralization (inactivation) of the virus.Results. When compared with the main control sample of an aqueous extract of chaga (Inonotus obliquus) with a 50% effective concentration equal to 13.72±2.99 μg/ml against 103 TCPD50/ml of SARS‐CoV‐2, superior activity was found for extracts of the spice Syzygium aromaticum L. and black tea from Nepal. Approximately equal inhibitory activity was detected for extracts of tea compositions based on black tea with the addition of the grass Thymus altaicus and the spice S. aromaticum L. or with the addition of seeds of Carum carvi L. and the root of Angelica archangelica L. In addition, such activity was detected for extracts of tea compositions based on green tea from China with the addition of leaves of Mentha piperita L. and flowers of Lavandula angustifolia MILL. or with the addition of the peel of Citrus sinensis L. and seeds of Pimpinella anisum L. Extracts from individual plant raw materials used to make tea compositions were black teas from India, Argentina, Vietnam and Sri Lanka, leaves of M. piperita L. and flowers of L. angustifolia MILL. Cetraria islandica lichen, green tea and berries of Oxycoccus also showed antiviral activity.Conclusion. The results obtained suggest that tea compositions based on black and green tea with the addition of various plant raw materials in the form of a regular drink can be useful to people with COVID‐19 infection.