Phytochemical composition and antioxidant evaluation of Pelargonium sidoides DC. root extract and proanthocyanidins

Abstract

Pelargonium sidoides roots have been used for medicinal purposes in various traditional medicine systems. Proanthocyanidins (PACN) are bioactive constituents of Pelargonium sidoides root extracts (PSRE) and possess antioxidant, anti-inflammatory, antibacterial properties [1]. PACN enriched extracts inhibit biofilm formation and adhesion of periodontopathogenic bacteria, inhibit proteolytic activities of bacteria [2]. PACNs could be perspective bioactive compounds beneficial in development and progression of periodontal diseases. The aim of this study was to determine proanthocyanidin composition in PSRE and collected PACN fraction. UPLC-MS analysis was used for the determination of proanthocyanidin profile and the estimation of the mean degree of polymerization (mDP) for the oligomers and polymers in PCAN. Reducing and radical scavenging activities of the extracts were determined using FRAP and ABTS assays, respectively. Five prodelphinidin derivatives were determined in the PSRE and PACN fraction (from dimers to hexamers). The calculated mean degree of polymerization for analysed PCANs sample was 6. The determined radical scavenging and reducing activities were 3747.75 ± 534.56 µmol/g (PSRE) and 4472.75 ± 707.71 µmol/g of TE (PACN) and 3210.17 ± 421.21 (PSRE) and 4006.13 ± 685.75 (PACN), respectively. The PACN fraction consisting of prodelphinidin oligomers showed significantly (p<0.05) higher Trolox equivalent antioxidant activity compared to PSRE. PACNs could be perspective for functionalization drug delivery systems of local action with natural active substance for treatment of periodontal diseases