Phenolic constituents, antimicrobial, antioxidant, and anticancer activities of ethyl acetate and n-butanol extracts of Senna italica

Different solvent extracts of the aerial parts of Senna italica ( Mill .) were investigated for their chemical constituents and biological activities. Moreover, bio-guided fractionation led to isolation and identification of six compounds, namely: physcion ( 1 ), emodin ( 2 ), 2-methoxy-emodin-6- O -β- d -glucopyranoside ( 3 ), 1-hydroxy-2-acetyl-3-methyl-6-hydroxy-8-methoxynaphthalene (tinnevellin) ( 4 ), quercetin 3- O -α- l -rhamnopyranosyl-(1→6)-β- d -glucopyranoside (rutin) ( 5 ), and 1,6,8-trihydroxy-3-methoxy-9,10-dioxo-9,10-dihydroanthracene ( 6 ). The chemical structures of these compounds were established via 1D and 2D 1 H- and 13 C-NMR spectroscopy. Ethyl acetate and n -butanol extracts as well as compound 3 were evaluated for their anticancer activity against tumor cell lines. The tested extracts showed a moderate to weak activity, while compound 3 showed a moderate activity against human liver cancer (Hep G2) and breast cancer (MCF-7) cell lines with IC 50 values of 57.5 and 42.3 μg/mL, respectively. Both ethyl acetate and n -butanol extracts exhibited antimicrobial activities with different strengths, i.e., ethyl acetate exhibited antimicrobial activity against seven test microbes while n -butanol extract showed antimicrobial activity against all tested microbes. This is the first report for the isolation of compound 3 as a new compound from S. italica growing in Egypt.