Man has used extracts of plants since the dawn of time and about 80% of the world’s population still use plant extracts for health care. The use of the extracts from medicinal plants in their natural form presents several difficulties. The actual content of the bioactive molecules from plants varies with both the locality and the season in which they are collected. This study, a comparative microbiological and chemical evaluation of the leaf extract of Piliostigma reticulatum was to determine its suitability or otherwise as a substitute for its co-generic species Piliostigma thonningii. This text is aimed at undergraduates and postgraduates who are interested in a future career in the phytomedicine, chemistry of natural products and pharmaceutical industry.