Identification and quantification of phenolic and fatty acid profiles in Pinus halepensis mill. seeds by LC‐ESI‐MS and GC: Effect of drying methods on chemical composition

This study aimed to evaluate Pinus halepensis Mill. seeds oil as well as methanolic‐aqueous extract on fatty acid and phenolic's composition as well as antioxidant activities with regard to the cones drying methods: convection and sun methods. The highest amounts of total phenols (14.63 ± 0.05 mg GAE/g DW), flavonoids (3.3 ± 0.02 mg QE/g DW), and condensed tannins (0.36 ± 0.05 mg CE/g DW) were showed in the seeds obtained by sun‐dried method. Methanolic‐aqueous seeds extracts were subjected to LC‐ESI‐MS analysis in order to identify and quantify the phenolic composition. This technique allowed us to identify eleven phenolic compounds: two phenolic acids and nine flavonoid compounds such as cirsiliol, catechin (+), luteolin, and luteolin‐7‐O‐glucoside, which were present in the two studied samples while apigenin, naringenin, and cirsilineol were only identified in the extract obtained from sun‐drying method seeds. The chemical components of the oils were analyzed using GC, and significant differences were found between the two studied seeds oil (p < .05). Furthermore, the antioxidant activities were investigated using DPPH and ABTS.(+) assays. The results showed that the methanolic‐aqueous extract from seeds dried by sun method had the highest antioxidant activities (0.08 and 0.05 mg/ml, respectively). This study could provide useful information for industry to produce potentially bioactive plant extract.