Identification and accumulation of phenolic compounds in the leaves and bark of Salix alba (L.) and their biological potential

• Published in: Biomolecules (Basel, Switzerland) Vol. 10; no. 10; p. 1391
• Main Authors: Piątczak, Ewelina, Dybowska, Monika, Płuciennik, Elżbieta, Kośla, Katarzyna, Kolniak-Ostek, Joanna, Kalinowska-Lis, Urszula
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 29.09.2020; MDPI
• Subjects: Acids; Alzheimer's disease; antioxidant activity; Antioxidants; Antioxidants - chemistry; Ascorbic acid; Bark; Benzothiazoles - chemistry; Biphenyl Compounds - chemistry; Calibration; Cell lines; Cell viability; cytotoxic activity; Cytotoxicity; Experiments; fibroblast cell line; Fibroblasts; Flavonoids - chemistry; Flavonoids - isolation & purification; Flavonols; Free Radical Scavengers - chemistry; Herbal medicine; Identification and classification; keratinocyte cell line; Keratinocytes; Leaves; Nutritional aspects; Pain; Phenolic acids; Phenols; Phenols - chemistry; Phenols - classification; Phenols - isolation & purification; Phytochemicals; Picrates - chemistry; Plant Bark - chemistry; Plant extracts; Plant Extracts - chemistry; Plant Leaves - chemistry; polyphenolic compounds; Polyphenols; Potassium; Salix - chemistry; Salix alba; Secondary metabolites; Solvents; Sulfonic acid; Sulfonic Acids - chemistry; Willows; Germany; Poland; cytotoxic activity; fibroblast cell line; antioxidant activity; keratinocyte cell line; polyphenolic compounds
• ISSN: 2218-273X; 2218-273X
• DOI: 10.3390/biom10101391

The study examines the phenolic compounds in hydromethanolic extracts of (L.) leaves and bark as well as their antioxidant activity and cytotoxic potential. UPLC-PDA-Q/TOF-MS analysis showed a total of 29 phenolic compounds in leaves and 34 in bark. Total phenolic compound content was 5575.96 mg/100 g of dry weight (DW) in leaves and 2330.31 mg/100 g DW in bark. The compounds were identified as derivatives of phenolic acids (seven in leaves and five in bark), flavanols and procyanidins (eight in leaves and 26 in bark) and flavonols (14 in leaves and three in bark). Both extracts exhibited strong antioxidant potential, assessed by radical scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS), but the bark extract was even stronger than the ascorbic acid used as a standard. The cytotoxicity of both extracts was evaluated against human skin fibroblasts and human epidermal keratinocytes cell lines using the Presto Blue cell viability assay. The keratinocytes were more resistant to tested extracts than fibroblasts. The leaf and bark extracts at concentrations which exhibited antioxidant activity were also not toxic against the keratinocyte cell line. Thus, extracts, especially the leaf extract, offer promise as a nontoxic natural antioxidant, in cosmetic products or herbal medicines, and as a source of bioactive secondary metabolites.