Chapter 16 In-vitro Assays for Determining Anti-HIV Potential of Phytochemicals Pascaline Fonteh, Walter Chingwaru, Debra Meyer, and Petrina Kapewangolo 16.1 Introduction The HIV epidemic continues to affect people worldwide. According to the UNAIDS fact sheet of 2018, approximately 36.9 million people were living with HIV in 2017 and since the start of the epidemic, approximately 35.4 million people had died from AIDS related illnesses (UNAIDS 2018). Antiviral treatment currently involves the use of combination antiretroviral ther- apy abbreviated as cART (Cihlar and Fordyce 2016). cART usually consists of two nucleotide or nucleoside reverse transcriptase inhibitors and a third drug from another class (Cihlar and Fordyce 2016). Such a combination is known to signifi- cantly suppress virus replication leading to substantial improvement in the clinical management of HIV infection by delaying disease progression, prolonging survival and improving the overall quality of life (Cihlar and Fordyce 2016). A total of 25 anti-HIV drugs from 6 different mechanistic classes have reportedly been devel- oped for use since the approval of zidovudine (AZT) in 1987 (Cihlar and Fordyce 2016). Limitations of existing treatment such as toxicity to the host, development of drug resistant viruses together with the persistence of latent pools of the virus makes lifelong treatment a necessity (Tang and Shafer 2012). AZT and other HIV-drugs originated from anti-cancer investigations of phytochemicals, the latter known for P. Fonteh Department of Surgery, University of the Witwatersrand, Johannesburg, South Africa W. Chingwaru Biological Sciences Department, Bindura University Science Education, Bindura, Zimbabwe D. Meyer Department of Biochemistry, University of Johannesburg, Johannesburg, South Africa P. Kapewangolo (*) Department of Chemistry & Biochemistry, University of Namibia, Windhoek, Namibia e-mail: pkapewangolo@unam.na © Springer Nature Singapore Pte Ltd. 2019 S. Kumar, C. Egbuna (eds.), Phytochemistry: An in-silico and in-vitro Update, https://doi.org/10.1007/978-981-13-6920-9_16 299