key: cord-1019315-20eoyy7z authors: Din, Misbahud; Ali, Fawad; Waris, Abdul; Zia, Fatima; Ali, Muhammad title: Phytotherapeutic options for the treatment of COVID‐19: A concise viewpoint date: 2020-08-20 journal: Phytother Res DOI: 10.1002/ptr.6786 sha: d7bde7e07a959da15a459cc35f1e3a0ab14afd30 doc_id: 1019315 cord_uid: 20eoyy7z nan limited therapeutic options are available (Li & De Clercq, 2020) . For centuries, traditional medicines have been used to cure several diseases including viral infections (Ahmad et al., 2020) . The phytotherapy-based approach to find new drugs have contributed as several plant species are a great source of modern medicines (Yaseen et al., 2019) . Similarly, plant-derived active compounds have been studied as viral inhibitors for many years (Serkedjieva, Manolova, Zgórniak-Nowosielska, Zawili nska, & Grzybek, 1990) . This study was aimed to briefly describe the potential use of ethno-medicinal research in searching new therapeutic options against COVID-19 and other coronaviruses and to provide some important directions to researcher for planning future studies. We have summarized various medicinal plants and their reported antiviral activities in Table 1 . There is the possibility that studies on plant-derived compounds listed in Table 1 have been not carried according to more recent scientific qualitative standards for plant-derived products (Heinrich et al., 2020) . For example, there is the possibility that high concentrations or doses have been used. The antiviral activities of medicinal plants have been mostly derived from laboratory studies (as clinical data are limited) and referred to multicomponent preparation of traditional medicines (Liu, Zhang, He, & Li, 2012) . Similarly, the qualitative standards for reporting clinical trials in herbal medicine are not as rigorous as in the conventional pharmaceutical field (Williamson, Liu, & Izzo, 2020) . In a study in 2012, it was reported that traditional herbal remedies along with Western medicines could help to improve symptoms, absorptions of pulmonary infiltrations, life-quality, and decrease corticosteroids uses in SARS patients (Liu et al., 2012 . The therapeutic effects of TCM herbal remedies for the treatment of SARS coronavirus have also been published (Luo et al., 2020; Yang et al., 2020) . Regardless the complex formulation of TCM, herbs such as Scutellaria baicalensis and Glycyrrhiza glabra were available in tested TCM preparations. The extracted baicalin and glycyrrhizin compounds from the mentioned herbs have in vitro evidences of anticoronaviral activity (Chen et al., 2004) . The anticoronavirus TCM remedies included plants such as Lonicerae japonicae, Saposhnikovia divaricate, Forsythia Vahl, and Atractylodis macrocephalae (Luo et al., 2020) . This could identify new directions for future research. For the treatment of coronavirus infections, two different research streams could be possibly followed to search useful phytotherapeutic compounds. One option is the herbal remedies that have potential preventive effects especially boosting the immune responses, that is, Echinacea purpurea and Astragalus membranaceus (Block & Mead, 2003) . Astragals has been used in TCM herbal formulation against SARS (Liu et al., 2012) . Immunomodulatory properties of polysaccharides and Uncaria tomentosa (from medicinal mushrooms) could also be used. The second option is the herbal remedies with therapeutic effects that have different antiviral mechanism of action. Regardless the etiology, clinical studies have proposed extract from plants, such as Pelargonium sidoides and Sambucus nigra to treat the infection of respiratory system (Agbabiaka, Guo, & Ernst, 2008; Hawkins, Baker, Cherry, & Dunne, 2019; Kalus et al., 2009 ). The anticoronaviral activities of polyphenols and pelargonium has also been studied (Michaelis, Doerr, & Cinatl Jr, 2011; Weng et al., 2019) . A set of compounds such as quercetin, kaempferol, and cryptotanshinone have been identified with anti-SARS-CoV action (Zhang, Wu, Zhang, Deng, & Peng, 2020) . Active compounds derived from medicinal plants has different antiviral mechanisms, such as viral pentation inhibition, replication inhibition or inhibiting the SARS-3CLpro activity . Such studies can expand the area of plant-based products to be investigated in future experiments. Similarly, the phytotherapy can be useful in the management or prevention the adverse effects of conventional drugs . 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