Influence of Extraction Methods on the Phytochemical Profile of Sambucus nigra L.

The aim of this work is to evaluate the influence of drying methods, extraction solvent, and extraction methods on the phytochemical profile of Sambucus nigra L. flowers harvested from the western region of Romania. Two drying methods for plant conditioning (room temperature and lyophilization), two extraction solvents (70% ethyl alcohol and water), and three extraction methods (conventional extraction (C), ultrasound-assisted extraction, and microwave extraction) were used. For the evaluation of the phytochemical profile, the following spectrophotometric methods were investigated: total polyphenol content, total antioxidant activity using the DPPH and FRAP methods, and flavonoid content. In addition to the spectrophotometric methods, the individual polyphenols were evaluated using the LC/MS method. Using atomic absorption spectrometry, the macro and microelement content of Sambucus nigra L. flowers was assessed. The results showed that the drying method, the solvent used for extraction, and the extraction method influenced the phytocompound content. The analyses showed that in terms of polyphenols, flavonoid content, and antioxidant activity, high values were recorded for lyophilization-dried samples compared to samples dried at room temperature. Also, higher values were recorded for alcoholic extracts compared to aqueous extracts, but also for extracts obtained by the ultrasound-assisted method, followed by extracts obtained via microwave compared to extracts obtained by conventional extraction.