Author(s): Ika Rahayu and Kris Herawan Timotius

Abstract: Moringa oleifera (MO) leaves have biological activities that are beneficial for improving health. In vitro studies show that its bioactive compounds prevent the development of some degenerative diseases. This study aimed to determine the bioactive compounds in hydroethanolic extracts of MO leave powder to measure its antioxidative and antimutagenic activity and to evaluate its ability to inhibit the SARS-CoV-2 main protease (Mpro) as a therapeutic target by in silico study. Liquid chromatography-mass spectrometry (LC-MS) was used to detect the bioactive compounds in hydroethanolic extract of MO leave powder. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) was used to measure the antioxidant activity. The antimutagenic activity was measured by using the free radical treated plasmid pBR322. Molecular docking was used to determine the interaction of the bioactive compounds and the Mpro of SARS-CoV-2. Total phenolic and flavonoids compounds of MO leave powder hydroethanolic extract are 50.02±0.14 mg GAE/g and 445.07 ± 4.09 mg QE/g, respectively. The main bioactive compounds in the hydroethanolic extract are Guanine and Luteolin-7-O-glucoside. The antioxidant activity of hydroethanolic extract of leave powder is IC50 118.9 ± 0.2 µg/mL, which is stronger than the standard BHT IC50 11.60 ± 0.30 µg/mL. The hydroethanolic extract also has the ability to protect DNA damage. In silico studies show strong energy bonds of Mpro molecules with Guanine and Luteolin-7-O-glucoside, and the binding energy values are -6.2 and -8.4 kcal/mol, respectively. The hydroethanolic extract of MO leaf powder contains Guanine and Luteolin-7-O-glucoside. It has excellent antioxidant activity, and the ability to maintain DNA integrity or antimutagenic properties. As bioactive compounds, Guanine and Luteolin-7-O-glucoside, have the ability to attach Mpro of SARS-CoV-2. In silico study indicates that hydroethanolic extract of MO leave powder can act as a medicinal ingredient that has anti SARS-CoV-2 properties.