HPTLC analysis of Rosmarinic and Caffeic acids in Salvia aegyptiaca extract and its antioxidant activities

Phenolic acids such as Rosmarinic (RA) and Caffeic acid (CA), are the most significant phenolic compounds in Lamiaceae family, including Salvia species. The aim of this study was to evaluate the RA and CA contents of Salvia aegyptica (SA) methanol extract and its antioxidant activity. RA and CA analysis were performed by HPTLC-image analysis. UV-VIS spectrophotometry was used for the evaluation of the phenolic acid.The samples were spotted on a HPTLC plate silica gel. The toluene- ethyl acetate- formic acid was used as mobile phase. Plates were scanning at ۳۶۶ nm and absorption mode was scanned. Finally, the image of plates was obtained by visualizer at ۲۵۴ and ۳۶۶ nm and visible wavelengths. This Method was then validated in terms of precision and accuracy at inter- day and intra-day.The extracts were screened to determine antioxidant activity using the DPPH radical scavenging assay, FRAP, ABTS, ORAC, Nitric oxide scavenging ability and cellular antioxidant activity.The RA and CA contents of extracts were ۱۱.۳۳ ± ۰.۳۶ and ۶.۳۶ ± ۴.۷ mg/g respectively.The SA were able to scavenge free radicals such as DPPH•, NO• and O۲•–, and the ability to reduce Fe۳+, as well. This activity highly associated with RA and CA contents. Developed HPTLC method is rapid, simple and reliable and it is suggested to use in routine assay of Salvia sp. extracts containing RA and CA which are a generally marker in various plant. Moreover, SA could be considered as natural source of antioxidants.