The isolation, structural characterization, and anticancer activity from the aerial parts of Cymbopogon flexuosus

This study investigated bioactive secondary metabolites from the aerial parts of Cymbopogon flexuosus (CF). Total phenolic and total flavonoid contents, the antioxidant activities including 2, 2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS⁺ ) and 2, 2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging systems, and cytotoxic effects were determined. 1, 3-O-di-E-caffeoylglycerol (SA3) and 1-O-p-coumaroyl-3-O-caffeoylglycerol (SA4) were firstly isolated from an ethanol extract of CF. Their chemical structures were elucidated by extensive spectroscopic analyses, including MS and NMR spectra as well as by comparison to the data reported in the literature. DPPH and ABTS⁺ radical scavenging tests showed that the highest antioxidant potent was detected for compound SA3 with IC₅₀ of 4.42 ± 0.18 and 21.84 ± 0.22 µg/ml, respectively. The compound SA3 stimulated the apoptotic factors of caspase-3, bax, and bcl-2 in HepG2 and caspase-3, caspase-9, P53 in A549. PRACTICAL APPLICATIONS: CF has been widely used as both a herbal drink and as a spice in diets. In the food processing industry, CF was used to process candy. In addition, it is used for the treatment of sore throat, cough, skin diseases, and other diseases in traditional oriental medicine. Recently, in Vietnam, CF has also been used to treat liver and lung cancer and consumed daily to process many dishes.