Abstract This dissertation comprises three distinct but related research. The first chapter deals with the phylogenetic relationship of the miracle plants and relatives, the second is on the evolution of miraculin, and the third chapter is on the ethnobotanical survey of African immigrants in the Sacramento region of California. In the phylogeny chapter, species in the genera Synsepalum and Englerophytum were studied using molecular techniques to investigate if the two genera are closely related. Synsepalum is a genus of trees and shrubs native to tropical lowland areas of Africa (Ayensu, 1978). It has glabrous staminodes and imbricate to valvate corolla lobes (Anderberg & Swenson, 2005). A very common feature in the genus is their fused sepals, a character that gave the name to the genus Synsepalum. The genus has a very wide range of distribution and is very prominent in Africa. There are no published reports on phylogenetic relationships within the genus. (Borg et al., 2019) their studies of the Englerophytum-Synsepalum complex reported six lineages of which four of them were composed solely of species in Synsepalum. There are, however, some concerns with the lineages reported. Some of the lineages had just a single species which is not the type species. More species are needed to better understand the clades in Synsepalum and to confirm the taxonomic relationships among the species in the genus. Synsepalum is confirmed to constitute more than one lineage suggesting it is not monophyletic in its current definition. Overall, the study suggests the need for a comprehensive evaluation of all species currently recognized in the two genera. On the evolution of miraculin, S. dulcificum (miracle berry) is one of the most prominent species in the genus due to its presence in the plant glycoprotein miraculin, a sweetening agent that helps in modifying taste. There are no reports as to whether miraculin is also produced in other species of the genus or not. In this study, using a PCR protocol, the presence of the gene responsible for miraculin was investigated in other species in the genera Synsepalum and Englerophytum. Two species of Synsepalum produced PCR amplification products for the gene for miraculin (Chr10G0299340) while none of the species of Englerophytum implicated in this study showed any sign of miraculin. The inferred amino acid sequences of miraculin from the species that produced PCR amplification products for the gene for miraculin were combined with those from species containing miraculin-like proteins to investigate the evolution of miraculin. It is revealed that miraculin is distinct from miraculin-like proteins due to the presence of histidine 30 and histidine 60, the residue responsible for the taste-modifying property of miracle berries. Miraculin-like protein contains only histidine 60. In chapter three, using a semi-structured questionnaire, African immigrants residing in different locations in and around Sacramento were interviewed on their use of medicinal plant knowledge after prior informed consent. Immigrants play a significant role in the transfer of medicinal plant knowledge, traditions, and cultures from their home country to their new area of primary residence. A total of 105 participants from 15 different African countries responded to the questionnaire. Participants were, between the ages of 20 and 60 comprising 65% female and 34% male. The result from this survey shows that many immigrants, though living in the global north where Western medicine is accessible, have rich knowledge of medicinal plants and still prioritize herbal medicines as an effective way to treat a wide variety of ailments.