This study aims to investigate the physicochemical characteristics, phenolics content, and oil composition of pomegranate oil seeds (PSO). Quality indices, pigments, phenolics content, and antioxidant activity were determined. PSO was fractioned into polar lipids: glycolipids (GL) and phospholipids (PL). Sterols profile and fatty acids composition of total lipids (TL), GL, and PL were determined by GC/FID. The free acidity, the peroxide value, and the specific extinction coefficients were, respectively, 1.69%, 3.42 in milliequivalents of active oxygen per kilogram of oil, 4.15, and 3.95. PSO is rich in phenols (93.42 mg/Kg) but poor in pigments. The sterols markers were β-sitosterol (77.94%), Δ5-avenasterol (7.45%), and campesterol (6.35%). Oil content was 12.2%, wherein 23.9% were GL and 24.35% were PL. TL were rich in unsaturated fatty acids (63.17%), while saturated fatty acids were more present in PL and GL (71.97% and 66.29%, resp.). Conjugated fatty acids were about 13.30%, 2.03%, and 4.91%, respectively, in TL, PL, and GL. The cis/trans ratio of TL, PL, and GL was, respectively, 49.82%, 42.91%, and 27.39%. Monounsaturated fatty acids were more bound in PL, whereas polyunsaturated fatty acids were more bound in GL. PSO is a good source of essential fatty acids, phenolics compounds, phytosterols, and lipid-soluble fractions.

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The main objective of this work was to study the effects of foliar biofertilizers on individual volatile profiles and phenolic compounds of olive oil (Olea europaea L. cv. Chemlali). Three foliar biofertilizers were used in two successive application seasons: T1 (rich in nitrogen, phosphorus and potassium); T2 (rich in calcium); and T3 (application of both T1 and T2). Results showed that foliar fertilization with T2 increased the phenolic compound contents (e.g., oleuropein aglycone and decarboxymethyl ligstroside aglycone) of Chemlali olive oil. It also enhanced the levels of many volatile compounds responsible for the good flavor of olive oil such as hexanal. However, T1-tested fertilizer led to a significant decrease in the content of phenolic compounds, although they seemed to improve significantly the levels of the majority of volatile compounds, especially hexanal. Based on these results, a significant relationship between plant nutrition and quality of oil was observed. Our results demonstrated a potential positive influence on the concentration of sensory quality compounds under T2 (Ca 2+ -based fertilizer). This result should be considered in the design of foliar nutrient application management strategies for olive trees.

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