Extraction, Isolation, Characterisation and Antioxidant Activity Assay of Catechin Gambir (Uncaria Gambir (Hunter). Roxb Phytochemical analysis and in vitro antioxidant activity of Uncaria gambir Antioxidant Activity of Catechins Isolate of Uncaria Gambier Roxb in Male Rats Identification of Potent COVID-19 Main Protease (Mpro) Inhibitors from Natural Polyphenols: An in Silico Strategy Unveils a Hope against CORONA Preparation of Oral Nutraceutical from Gambier Extract CoViD-19: An early intervention therapeutic strategy to prevent developing a severe disease as an alternative approach to control the pandemic