Jurnal Biodjati 8(1):163–171, May 2023 http://journal.uinsgd.ac.id/index.php/biodjati e-ISSN : 2541-4208 p-ISSN : 2548-1606 In Silico Analysis of Catechin, Galangin, and Hesperidin as Competitors of the SARS-CoV-2 Spike Protein Astuti Kusomorini *1 , Nisrina Hasna 2 , Yani Suryani 3 , Opik Taufqurrahman 4 INTRODUCTION SARS-CoV-2 is a zoonotic virus that spreads from animals to humans via the An- giotensin-converting Enzyme 2 (ACE-2) re- ceptor (Guo et al., 2020). This virus has mu- tated into several variants, including Alpha (B.1.17), Beta (B.1.351), Delta (B.1.617.2), Omicron (B.1.1.529), and others (Indone- sian Ministry of Health, 2020). Patients with this disease exhibit mild to moderate symp- toms such as fever, headache, dry cough, sore throat, and blown or breathlessness (Sohrabi et al., 2020; Su et al., 2020). Angiotensin-con- verting enzyme-2 (ACE-2) is a type 1 integral membrane protein expressed in some tissues, including the heart, respiratory tract, and di- gestive tract. This protein is the virus's frst contact point with the human body's cells (Basu et al., 2020). Coronavirus disease-2019 (COVID-19) patients are treated medically by reducing symptoms, such as administering antivirals. Favipiravir is an antiviral compound used Citation Kusumorini, A., Hasna, N., Suryani, Y. & Taupiqurrohman, O. (2023). In Silico Analysis of Cat- echin, Galangin, and Hesperidin as Competitors of The SARS-CoV-2 Spike Protein. Jurnal Bio- djati, 8(1), 163–171. DOI: 10.15575/biodjati.v8i1.24521 *Corresponding author Abstract. Currently, Covid-19 has become endemic. However, the de- velopment of Covid-19 drugs continues to be carried out to suppress the growth of the Sars-Cov-2 virus. Some compounds with antiviral activity are catechin, galangin, and hesperidin. Angiotensin-convert- ing enzyme-2 (ACE-2) is a protein that enters viruses into the cell. Based on that, ACE-2 can be used as a primary target to suppress the development of the Sars-Cov-2 virus. This study aimed to test the catechin, galangin, and hesperidin compounds in inhibiting the SARS CoV-2 virus from attaching to ACE-2 by trying the interactions of catechin, galangin, and hesperidin compounds with ACE-2 using the in-silico method. The material used was the three-dimensional struc- ture of the compounds catechin, galangin hesperidin, and ACE-2. The tools used were FAF-Drugs4, Discovery Studio, and Pyrex software. Low-afnity energy values (kcal/mol) indicate promising results. The results showed that the energy afnity value of catechin was -6.2 kcal/ mol, galangin was -6.3 kcal/mol, and hesperidin was -8.3 kcal/mol. This value is lower than the control afnity energy (chloroquine and favipiravir), which is -5.2 kcal/mol and -4.8 kcal/mol, respectively. Based on this, catechin, galangin, and hesperidin can be used as in- hibitors/competitors for the Sars-Cov-2 to attach to ACE-2. Keywords: ACE-2, COVID-19, favonoid, molecular docking, SARS- CoV-2 1,2,3 Department of Biology, Faculty of Science and Technology UIN Sunan Gunung Djati, Bandung 40614 e-mail: 1* astutiAuinsgd.ac.id 2 nisriniahasna14@gmail.com 3 yani.suryani@uinsgd.ac.id 4 otaupiqurrohman@gmail.com Received: 11 February, 2023 Revise from: 20 February, 2023 Accepted: 09 May, 2023 Copyright © 2023 Jurnal Biodjati This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0/)