Phytochemical study, antioxidant and antimicrobial activities of aqueous extracts of bryophyllum pinnatum and kalanchoe crenata

Background: In underdeveloped countries, the emergence of microbial diseases is amplified by drug resistance, hence the perpetual search for alternative solutions to fight infectious diseases. Bryophyllum pinnatum and Kalanchoe crenata (Crassulaceae), are two plants used in traditional medicine for the treatment of various skin diseases in infants. The objective of this work is to study the aqueous extracts of fresh leaves of these two plants to know their composition in secondary metabolites and their antioxidant and antimicrobial potentialities. Methods: Phytochemical analysis was performed by Thin Layer Chromatography (TLC) while 2, 2-diphenyl-l-picrylhydrazyl (DPPH) method was used to evaluate the antioxidant activities of the studied extracts. Antimicrobial activities were evaluated by liquid and solid medium dilution methods on Staphylococcus aureus and Trichophyton rubrum. Results: This study revealed the presence of polyphenols, flavonoids, sterols and terpenes, followed by a low antioxidant activity of the aqueous extracts of both plants. Antimicrobial tests showed that both extracts were active on S. aureus. However, B. pinnatum was twice as active as K. crenata. On T rubrum, both extracts are not active because they did not show any inhibition of the germ. Conclusion: This study reveals the presence of natural substances with antimicrobial properties in the plants studied. It justifies the use of both plants in the treatment of Staphylococcal skin infections in infants.