Bryophyllum constitutes a subgenus within the genus Kalanchoe that contains several plant species used in traditional medicine worldwide for the treatment of several diseases. However, little is known about the phytoconstituents of Bryophyllum spp. and previous reports have pointed at their low in Planta concentrations of bioactive compounds. In this work, we take advantage of plant in vitro culture for the study of the phenolic compounds found in the aerial parts of Bryophyllum spp. and their associated bioactivities. Our results show that the induction of nutritional stress leads to an improved accumulation of phenolic compounds, mainly flavonols and anthocyanins, represented by myricetin and malvidin glycosides, respectively. This effect is mainly found for B. × houghtonii, whose hydroethanolic extracts promoted the highest antioxidant, cytotoxic and anti-inflammatory activities. In the case of cytotoxic activity, Bryophyllum extracts showed an enhanced activity against the MCF-7 human breast carcinoma cell line. Meanwhile, extracts from B. daigremontianum promoted a wide range of effectiveness against different bacterial and fungal strains. This study is committed to shed light about the phytochemical potential associated to this unexplored subgenus, with the aim of considering Bryophyllum spp. as a valuable source of bioactive compounds for their exploitation in food, cosmetic and pharmaceutical industries.
