Phenolic compounds and antioxidant and cytotoxic properties of maritime pine (Pinus pinaster Ait.) bark extracts Artigo de Conferência uri icon

resumo

  • Maritime pine (Pinus pinaster Ait.) is a pine species native to the western Mediterranean basin which has an economic importance in southwestern Europe due to the industrial uses of its wood. Other parts of the tree, including the bark, are considered by-products, and they stand out because of the presence of secondary metabolites, such as phenolic compounds. These compounds have biological potential, making them suitable to produce food supplements and functional foods, among other applications [1]. Two extracts were obtained from maritime pine bark by microwave assisted extraction (MAE) and ultrasound assisted extraction (UAE), and their phenolic compound content and antioxidant and cytotoxic properties were analysed. Phenolic compounds analysis was carried out by HPLD-DADESI/ MS [2]. Antioxidant properties were measured via thiobarbituric acid reactive substances (TBARS) formation inhibition method in brain cell homogenates, cellular antioxidant activity (CAA) in murine macrophage cells RAW 246.7, and oxidative haemolysis inhibition assay (OxHLIA) in sheep blood erythrocytes [2,3]. The cytotoxic properties of the extracts were screened in tumour and non-tumour cells by the sulforhodamine B assay [3]. The MAE showed a greater yield of extraction, three times higher than UAE. Major phenolic compounds in maritime pine extracts were catechin and B-type procyanidins, and some A-type procyanidins and taxifolin derivatives were also found in both extracts. The best antioxidant activity results were observed in the TBARS method and OxHLIA, especially in the case of the extract obtained by MAE, although it did not showed CAA at the maximum concentration studied (2 mg/mL), unlike the extract obtained by UAE, which showed some activity at that concentration. Regarding cytotoxic properties, the two extracts showed similar results since they presented activity in tumour and nontumour lines with IG50 values higher than those observed with the positive control (ellipticine). Therefore, MAE was a better extraction method for obtaining a functional extract from maritime pine bark.

data de publicação

  • novembro 2022