In vitro human digestion simulation of the bioavailability and antioxidant activity of phenolics from Sambucus ebulus L. fruit extracts

Abstract

Bioavailability is an important concept when evaluating natural products for their bioactivities. The present study measured the bioavailability of phenolics of Sambucus ebulus (dwarfelder) fruit extracts, along with its antioxidant activity after simulated digestion. Total phenolics, phenolic acid, proanthocyanidin and flavonoid content assays were used along with different antioxidant assays such as metal reducing and free radical scavenging activities. High performance thin layer chromatography was used to measure bioactive metabolite of the plant sample, chlorogenic acid. Results indicated that aqueous and methanolic extracts of S. ebulus fruits were affected by simulated human digestion, alterations in antioxidant activity were consistent with the changes in the phenolics. Chlorogenic acid bioavailability rates were calculated as 45.8 and 51.9% for methanolic and aqueous extracts, respectively. Total antioxidant capacity was reduced to 37 ± 0.5 from 82 ± 4 (AAE)/g DE for methanolic extracts after the digestion process.