Protective effects of Sedum caespitosum and its polyphenolic compounds against to H2O2 induced cytotoxicity

There are 33 Sedum species growing in Turkey and some Sedum species have been employed in folk medicine for their antidiarrheic, wound healing, and diuretic properties as well as treatment of chronic viral hepatitis.The crude MeOH extract prepared from the aerial parts of Sedum caespitosum (Cav.) DC. and its EtOAc, n-BuOH, H₂O subextracts were screened for their protective effect against to H₂O₂ induced cytotoxicity at different concentrations in human red blood cell. The EtOAc subextract were found to be the most protective one and its chemical composition was further analysed. Five polyphenolic secondary metabolites including gallic acid (1), kaempferol 3- α-rhamnopyranoside (2), quercetin 3-O-β-glucopyranoside (3), quercetin 3-O-α-rhamnopyranoside (4), myrcetin 3-O-α-rhamnopyranoside (5) were isolated from the EtOAc extract by successive chromatographic methods. The structures of the isolated compounds were elucidated by 1D- and 2D-NMR techniques. This is the first phytochemical work on S. caespitosum. The protective effect of the isolates against to H₂O₂ induced cytotoxicity in human red blood cells also evaluated at 5 and 10µg/ml and kaempferol 3-α-rhamnopyranoside was shown most protective effect.

Acknowledgement: Authors are grateful to Prof. Dr. Hayri Duman, Gazi University, Ankara for identification of plant material.