Biomass waste material consisting of Posidonia oceanica (P. oceanica) leaves was collected from the shore in Calpe, Alicante (Spain) (38°38′09″N 0°04′16″E) in February–March 2017 (two different batches were collected). The collected leaves had a dark brown coloration. The material was washed vigorously with water to remove sand and salts and stored at 4 °C until its use.
2,2′-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), (±)-6-Hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox) 97%, ethanol (>99.8%), toluene, acetic acid, formic acid and sodium persulphate were purchased from Sigma–Aldrich (Darmstadt, Germany). The Folin–Ciocalteau reagent, modified Lowry reagent and bovine serum albumin were obtained from the “modified Lowry protein assay kit” purchased from Thermo Fisher scientific (Madrid, Spain). All the salts, reagents and monosaccharides used for the carbohydrate composition analysis were purchased from Merck (Sigma, Darmstadt, Germany).
2,2′-Azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), (±)-6-Hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox) 97%, ethanol (>99.8%), toluene, acetic acid, formic acid and sodium persulphate were purchased from Sigma–Aldrich (Darmstadt, Germany). The Folin–Ciocalteau reagent, modified Lowry reagent and bovine serum albumin were obtained from the “modified Lowry protein assay kit” purchased from Thermo Fisher scientific (Madrid, Spain). All the salts, reagents and monosaccharides used for the carbohydrate composition analysis were purchased from Merck (Sigma, Darmstadt, Germany).