Trolox standard

HPLC-grade acetonitrile and methanol were purchased from Carlo Erba, Spain. All chemicals were of analytical grade. Quercetin and vanillic acid were purchased from Fluka, Honeywell, Charlotte, North Carolina, USA. Sodium carbonate (anhydrous) and calcium chloride (anhydrous) were purchased from Merck, Darmstadt, Germany. Trans-resveratrol and gallic acid were purchased from Sigma Aldrich, Darmstadt, Germany. Dialysis tube (SnakeSkin TM Dialysis Tubing, 10K MWCO, 22 mm) was purchased from Thermo Fischer, Waltham, Massachusetts, USA. Raw Bombyx mori silk was obtained from Bursa Institute for Silkworm Research (Bursa, Turkey). ABTS assays were performed by using ABTS (2,2′-Azinobis-(3-Ethylbenzthiazolin-6-Sulfonic Acid)), purchased from Roche (Mannheim, Germany) and potassium persulfate (K₂S₂O₈) from Carlo Erba Reagents (Val-de-Reuil, France). Trolox standard was achieved from Acros Organics (Geel (Belgium). Methanol, a Merk product (99% purity), was used as such, for dilution and solubility experiments.

The methanol and acetonitrile used were HPLC (high-performance liquid chromatography) grade and purchased from Fisher Scientific, as well as the potassium sodium tartrate tetrahydrate used for reducing sugar determination and D-glucose standard (Madrid, Spain). Choline chloride, betaine, 1,2-propanediol, and albumin standard were from Thermo Fisher Scientific (Madrid, Spain), and triethylene glycol and Trolox standard were supplied by Acros Organics (Antwerp, Belgium). The HPLC standards, trifluoroacetic acid, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) were purchased from Sigma Aldrich (St. Louis, MO, USA)l; Folin-Ciocalteu reagent and ethanol were obtained from Scharlau (Barcelona, Spain); and 3,5-dinitrosalicylic acid was purchased from Alfa Aesar (Kandel, Germany). Mueller–Hinton Broth culture media and bacteriological agar for microbiological assays were supplied by Oxoid (Basingstoke, Hampshire, UK).