Medicinal plants with anti-SARS-CoV activity repurposing for treatment of COVID-19 infection : a systematic review and meta-analysis.

The novel SARS-CoV-2 (severe acute respiratory syndrome  coronavirus) has emerged as a significant threat to public  health with startling drawbacks in all sectors globally. This  study investigates the practicality of some medicinal plants  for SARS-CoV-2 therapy using a systematic review and  meta-analysis of their reported SARS-CoV-1 inhibitory  potencies. Relevant data were systematically gathered from  three databases, viz., Web of Science, PubMed and Scopus.  The information obtained included botanical information,  extraction method and extracts concentrations, as well as  the proposed mechanisms. Fourteen articles describing 30  different plants met our eligibility criteria. Random effects  model and subgroup analysis were applied to investigate  heterogeneity. According to subgroup analysis, the sub?stantial heterogeneity of the estimated mean based on the  IC50 values reporting the most potent anti-SARS-CoV 3C-  -like protease (3CLpro) inhibitors (10.07 %, p < 0.0001), was  significantly higher compared to the most active anti?SARS-CoV papain-like protease (PLpro) inhibitors (6.12 %,  p < 0.0001). More importantly, the literature analysis revealed  that fruit extracts of Rheum palmatum L. and the compound  cryptotanshinone isolated from the root of Salvia miltiorrhiza (IC50 = 0.8 ± 0.2 mmol L–1) were excellent candidates for anti-  -SARS-CoV targeting PLpro. Meanwhile, iguesterin (IC50 =  2.6 ± 0.6 mmol L–1) isolated from the bark of Tripterygium regelii emerged as the most excellent candidate for anti-SARS-  -CoV targeting 3CLpro. The present systematic review and  meta-analysis provide valuable and comprehensive infor?mation about potential medicinal plants for SARS-CoV-2  inhibition. The chemotypes identified herein can be adopted  as a starting point for developing new drugs to contain the  novel virus.