Steroidal lactones from Withania somnifera effectively target Beta, Gamma, Delta and Omicron variants of SARS-CoV-2 and reveal a decreased susceptibility to viral infection and perpetuation: a polypharmacology approach - Aditi Srivastava; Rumana Ahmad; Irshad A. Wani; Sahabjada Siddiqui; Kusum Yadav; Anchal Trivedi; Shivbrat Upadhyay; Ishrat Husain; Tanveer Ahamad; Shivanand S. Dudhagi (In Silico Pharmacology, 2024)