Characterization of water and ethanolic extracts of turkish propolis by hplc and GC-MS

Propolis is an adhesive, resinous substance collected by honey bees from various plant sources. Ethanolic extract of propolis is widely used for obtaining resin-free concentrated propolis extracts. Water extract of propolis and its components containing caffeoylquinic acids have a strong antioxidant activity and inhibitor/activator effects on some enzymes. Characterization of all components of propolis involves qualitative and quantitative chemical analysis. Chromatographic techniques, especially HPLC and GC-MS provide identification and determination of profiling of each polyphenolic compounds. The aim of this study is qualitative and quantitative determination of contents of Turkish propolis, a food supplement used by people, collected from various regions of Turkey using HPLC-DAD and GC-MS in water extract containing caffeoylquinic acids that is responsible of its antioxidant activity, and also ethanolic extract. In HPLC-DAD analyses, it was determined that water extract of Turkish propolis contains phenolic acids such as caffeic acid (204.00 µg/mL), trans-cinnamic, chlorogenic, and caffeoylquinic acids; whereas, the alcoholic extract of Turkish propolis contains chrysin (641.33 µg/mL), caffeic acid phenethyl ester (630.67 µg/mL), pinocembrin (572.67 µg/mL), galangin (534.11 µg/mL), naringenin (372.39 µg/mL), and also kaempferol, trans-cinnamic acid, caffeic acid, myricetin and quercetin. GC-MS analyses done with Rtx-1 and Rtx-5ms columns showed that more compounds have been detected by Rtx-5ms column in water extract of propolis. It was determined that water extract of propolis contains quinic acid and ferrulic acid by Rtx-5ms column, whereas ethanol extract of propolis contains caffeic acid by Rtx-1 column. Various sugar derivatives were detected by both columns in water and alcoholic extracts of Turkish propolis.