Exosomes are a subpopulation of membrane-derived cellular vesicles (30−150 nm) that play an important role in intercellular communication. Because of their natural function as nanocarriers, several applications have been developed for these nanovesicles, including drug delivery. Here we loaded saponins and flavonoids obtained from a black bean extract (Phaseolus vulgaris L.) with antiproliferative activity into exosomes extracted from different cell lines to induce an enhanced response in vitro. We demonstrated that exosomes can be loaded with at least three different phytochemicals in a one-step process to deliver these compounds to recipient cells. Moreover, we found that the bioactivity of the exosomal extract is greater than those observed in other formulations of the same extract. Our results suggest that exosomes are a promising alternative for improved delivery of complex mixtures of bioactive compounds, such as plant extracts. Therefore, future applications for these nanovesicles may include the development of new products for human use with enhanced nutraceutical properties.