Phenolic extract of almond (Prunus amygdalus L.) pericarpe restores lipid metabolism in hyperlipidemic mice and prevents plasma lipoprotein oxidation

This work was designed to study the effect of a polyphenol-rich extract from the pericarpe of sweet almond (Prunus amygdalus L.) on the plasma lipid profile in Triton WR-1339-induced hyperlipidemic mice and on the prevention of lipoprotein oxidation. It is noted that the phenolic extract significantly reduces total plasma cholesterol by 58% (P < 0.001) and triglycerides by 62% (P < 0.001). In addition, this extract significantly reduces the elevated LDL-cholesterol level by 61% (P < 0.05) and increases HDL-cholesterol by 71% (P < 0.05). The extract also significantly lowered the value of the atherogenicity index by -72% (P < 0.01) and that of the LDL/HDL ratio by 55% (P < 0.05). On the other hand, this extract has a dose-dependent 2,2-diphenyl-1-picrylhydrazyl anti-radical effect with an IC50= 18.8 ± 0.55 μg/ml and significantly inhibits the oxidation of the lipoprotein-rich plasma (IC50 = 13.8 ± 0.57 μg/ml). Our results show that the extract is rich in polar polyphenols (total polyphenols: 342.63 ± 3.44 mg/g, tannins: 144.67 ± 6.83 mg/g, flavonoids: 20.66 ± 0.92 mg/g), which could improve lipid metabolism and prevent the oxidation of lipoproteins and thus have a beneficial effect in the prevention of atherosclerosis and the related cardiovascular diseases.