Changes in phytochemical, antimicrobial and free radical scavenging activities of the Peruvian pepper tree (Schinus molle L.) as influenced by fruit maturation

The effect of stage of maturity on total lipids, fatty acids, yields and essential oil composition and their antimicrobial and free radical scavenging activities of the Schinus molle fruits was investigated. The content of total lipids varied from 2.87 to 5.35% (w/w, dw) and were rich in unsaturated fatty acids particularly linoleic acid. As maturation progress, the essential oil yield dropped from 5.18% to 1.15%. Monoterpene hydrocarbons with α-phellandrene (35.15–40.38%), limonene + β-phellandrene (21.47–36.62%), β-myrcene (7.61–24.96%) and α-pinene (1.92–2.58%) were found to be the main components. At the same time, the essential oils were evaluated for their antimicrobial and free radical scavenging activities. They were found to be active against Bacillus subtilis, Bacillus cereus, Salmonella typhymurium and Escherichia coli but they do not inhibit the growth of Candida albicans. Conversely, they showed very weak activity against the DPPH radical. In both assay, the oil derived from the intermediate stage was reported as more efficient.

► Ripening of Schinus molle fruits was concomitant to an increase of total lipids content and remarkable changes in fatty acids profile.
► Gradual increase in saturated and monounsaturated fatty acids has been observed.
► The maturation process was associated with a significant decrease in essential oil yield and quantitative variations in the content of the main components.
► Whatever the stage of maturity, the essential oil showed weak antiradical and moderate antibacterial activity against subtilis, B. cereus and S. typhymurium, but no activity was observed against the yeast C. albicans.