Exploring the healing power of Pistacia lentiscus stems: insights into extraction methods, polyphenolic composition, and health-promoting activities

Abstract

ABSTRACT This work aimed to evaluate the effect of different extraction solvents on the polyphenolic content, antioxidant and antibacterial activity of Pistacia lentiscus stems. The results obtained show that the extraction yield depends strongly on the polarity of the solvent and the extraction method. The ethanolic extract had the highest yield in both extraction methods investigated, namely Soxhlet (R = 9.89%) and cold maceration (R = 9.20%). The free radical scavenging activity of the extracts showed that the ethanolic extract had the highest antioxidant activity in both extraction methods with an IC50 = 0.023 mg/mL (cold maceration) and an IC50 = 0.034 mg/ml (Soxhlet). The HPLC analysis of the extracts indicates that gallic acid and catechin are the major phenolic compounds. The FTIR results showed that the shift of the stretching is responsible for O-H and C-H bonding. The GC-MS analysis revealed the presence of stearic acid and palmitic acid methyl ester as main compounds. The bacterial analysis of the extracts showed that the aqueous extract represents the most active one against Staphylococcus aureus and Pseudomonas aeruginosa; on the other hand, no antifungal activity was appreciated. Overall, the results indicate that the investigated extracts might be considered valuable sources of bioactive compounds.