Studied of Prunus serotine oil extracted by cold pressing and antioxidant effect of P. longiflora essential oil.

Prunus serotine oil, was extracted from the seeds without shells, resulting in an oil yield of 23.41 ± 3.62%. Through GC it was shown that 52.38% of the total fatty acids present in the oil were polyunsaturated fatty acids. The fatty acids profile presented in the P. serotine oil were oleic (41.42%), linoleic (26.97%) and α-eleostearic acid (25.33%). It had a high concentration of total phenols (221 ± 15.85 mg as gallic acid equivalents/kg oil) and flavonoids (0.77 ± 0.01 mg catechin equivalents/kg oil). The antiradical activity was 31.52 ± 2.71% and 12.94 ± 0.67% of radical inhibition for colorimetric methods using ABTS [2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid)] and DPPH (2,2-diphenyl-1-picrylhydrazyl), respectively. The activity inhibition was 2.3 (ABTS) and 1.8 (DPPH) times higher, respectively, than the ones of Prunus dulcis oil. Lipid oxidation showed that at day nine, P. serotine oil has it maximum hydroperoxide production through two methods (hydroperoxide and MDA). Three oregano fractions were added (code: 642, 655 and A01) as natural antioxidants at four different concentrations (3000, 300, 30 and 3 ppm) each one, to extend its shelf life. Fraction 642 managed to extend its shelf life until day 30 (30 °C ± 2 °C), in both methodologies. The fraction 642 at 3 ppm, controls the production of hydroperoxide formation. Resulting in values of 3.65 µM equivalents of cumene hydroperoxide/kg of oil and 10.29 µM equivalents of 1,1,3,3-Tetraethoxypropane/kg of oil, decreasing by 3.2 times the peroxide formation with respect to P. serotine oil without leaving a Poliomintha longiflora fraction.