Phenolic screening, antioxidant activity and diuretic effect of Moroccan Pinus pinaster Bark extract.

Objective: This study aims to evaluate the chemical composition antioxidant activity, and diuretic effects of Moroccan Pinus pinaster bark ethanolic extract (PPBE).

Materials and methods: The phytochemical composition of PPBE was assessed using HPLC-DAD. Total polyphenols and flavonoids were quantified using the Folin-Ciocalteu and aluminum trichloride methods, respectively, while mineral content was determined by plasma mass spectrometry. Antioxidant activity was assessed using the reducing power assay, total antioxidant capacity, and anti-DPPH free radical assay. For the diuretic effect, sixteen male Wistar rats were divided into four groups: control (distilled water, 10 ml/kg of BW), furosemide (10 mg/kg of BW), and PPBE (200 and 400 mg/kg of BW) groups. After 15 days, plasma and urine were collected for creatinine, potassium, and sodium analysis, along with urine output measurement. Statistical analysis employed one-way ANOVA followed by Tukey multiple comparison test.

Results: The PPBE displayed high phenolic content and potent antioxidant properties. Besides, the PPBE phenolic screening showed nine phenolic compounds with ferulate glucoside, gallic acid, and catechin as the main compounds. The PPBE demonstrated a richness in essential minerals. Furthermore, at both doses (200 and 400 mg/kg) PPBE led to a notable elevation in urine flow, urinary sodium concentration, and creatinine clearance, without affecting plasma electrolytes. In contrast, furosemide caused a reduction in plasma potassium levels.

Conclusion: PPBE could serve as a bioactive component, antioxidant, or preservative in food formulation. Moreover, it exhibits a diuretic effect without altering plasma composition.