In Silico Prediction of Biomarkers from Amaranthus tricolor (L) Targeted against HIV-1 Protease

Acquired immunodeficiency syndrome is caused by a retrovirus human immunodeficiency virus (HIV). Resistance to antiviral drugs is alarming in antiretroviral therapy and medical management of HIV- infected patients. Thus, identifying novel antiviral drugs is critical and medicinal plants are an excellent source for such discoveries. The current study aimed to isolate and characterize the chemical constituents from leaves of Amaranthus tricolor (L) and to discover novel HIV- 1 protease inhibitors. Amaranthus tricolor methanolic extract (ATME) was fractionated into chloroform and aqueous phases. The chloroform fraction was separated by column chromatography using mobile phase n-hexane: ethyl acetate (6:4 v/v). Among various fractions, SOWIS-III was purified and studied for structural interpretation. The compounds were docked with HIV-1 protease as a drug target. The structural interpretation of the SOWISIII fraction was identified as flavanol glycoside 24methylene cycloartanol and SOWIS-P as a gallic acid derivative methyl 3,4,5-trihydroxybenzoate. The docking studies of 24-Methylenecycloartanol and HIV1 protease showed 10 amino acid interactions with the estimated free energy of binding of -10.14 kcal/mol and the antiviral activity depicted as 36.88 nM. Methyl 3,4,5-trihydroxybenzoate and HIV-1 protease show five amino acid interactions with the estimated free energy of binding of -5.03 kcal/mol with 205.24 mu M estimated antiviral activity. Hence, 24-methylene cycloartanol and methyl 3,4,5-trihydroxybenzoate can serve as drug candidates for HIV.