Antimicrobial, Antioxidant and Cytotoxic Potential of Caesalpinia pulcherrima Flower

Most of the world’s populations residing in developing countries depend on alternative medicine and use of plant ingredients. Caesalpinia pulcherrima (Fabaceae) is used in folk medicine for the treatment of various diseases including asthma, bronchitis, cholera, diarrhea, dysentery and malarial infection. The present study was undertaken to determine antimicrobial, antioxidant and cytotoxic activities of flower extracts of this Ayurvedic plant. Antimicrobial activity was tested against Staphylococcus aureus (G+ve bacteria), Pseudomonas aeruginosa (G-ve bacteria), Candida albicans (yeast) and Aspergillus Niger (Fungi) by Disc agar plate method. Antioxidant activity was determined by DPPH free radical scavenging assay, Ferric reducing assay and total antioxidant capacity determination. Cytotoxic activity was evaluated via using preliminary brine shrimp lethality test and toward liver cancer cell line; HepG2. Among the methanol extracts and the fractions, butanol fraction showed the highest phenolic content (490.52 mg gallic acid/g) and the antioxidant capacities of the 90% methanol extract were 444.4, 0.679, 19.11μmol/g in TAC, RPAA and DPPH assays, respectively. This study verified that the extracts and butanol fraction from C. pulcherrima have strong antioxidant activity that was correlated with their high level of phenolic content. Furthermore, the same extract showed appreciable cytotoxic activity via HEPG2 assay, the IC 48.6 μg/mL. A marked antimicrobial and antioxidant activity of 50 flower extracts was observed which may be attributed to the presence of phenolic compounds and other phytochemicals. It is concluded that C. pulcherrrima can be used to control infectious diseases and oxidative damage.