Extraction, Solubility and Antimicrobial Activity of (-) Usnic Acid in Ethanol, a Pharmaceutically Relevant Solvent
Usnic acid (UA) is the most studied bioactive secondary metabolite from lichens. Recently, UA research has focused on its antibacterial activity. However, increased application in healthcare products of UA is hampered by low solubility in aqueous solutions. Here, we report ethanol both as an alterna...
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crsagepubl:10.1177/1934578x1701200725 2024-09-15T18:32:15+00:00 Extraction, Solubility and Antimicrobial Activity of (-) Usnic Acid in Ethanol, a Pharmaceutically Relevant Solvent Ahmad, Rafi Borowiec, Paulina Falck-Ytter, Anne Bergljot Strætkvern, Knut Olav 2017 http://dx.doi.org/10.1177/1934578x1701200725 http://journals.sagepub.com/doi/pdf/10.1177/1934578X1701200725 en eng SAGE Publications http://journals.sagepub.com/page/policies/text-and-data-mining-license Natural Product Communications volume 12, issue 7, page 1934578X1701200 ISSN 1934-578X 1555-9475 journal-article 2017 crsagepubl https://doi.org/10.1177/1934578x1701200725 2024-07-22T04:33:12Z Usnic acid (UA) is the most studied bioactive secondary metabolite from lichens. Recently, UA research has focused on its antibacterial activity. However, increased application in healthcare products of UA is hampered by low solubility in aqueous solutions. Here, we report ethanol both as an alternative extraction solvent to acetone and as a pharmaceutically relevant solvent for future formulations. Dried samples of the abundant reindeer lichen ( Cladonia stellaris) were extracted in a 2 3 factorial design using either ethanol or acetone, varying both time and solvent-to-dry mass ratio. In both extracts, UA was the predominant compound as shown by two-dimensional thin-layer chromatography (TLC). In a disc diffusion assay, both extracts demonstrated similar antibacterial susceptibility towards Gram-positive ( Bacillus subtilis and Staphylococcus aureus), while showing little to no activity against Gram-negative bacteria ( Escherichia coli and Pseudomonas aeruginosa). Among a range of pharmaceutically relevant solvents tested, UA was only soluble in ethanol (at concentrations up to 1–2 mg mL −1 ). Article in Journal/Newspaper Reindeer lichen SAGE Publications Natural Product Communications 12 7 1934578X1701200 |
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Open Polar |
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SAGE Publications |
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English |
description |
Usnic acid (UA) is the most studied bioactive secondary metabolite from lichens. Recently, UA research has focused on its antibacterial activity. However, increased application in healthcare products of UA is hampered by low solubility in aqueous solutions. Here, we report ethanol both as an alternative extraction solvent to acetone and as a pharmaceutically relevant solvent for future formulations. Dried samples of the abundant reindeer lichen ( Cladonia stellaris) were extracted in a 2 3 factorial design using either ethanol or acetone, varying both time and solvent-to-dry mass ratio. In both extracts, UA was the predominant compound as shown by two-dimensional thin-layer chromatography (TLC). In a disc diffusion assay, both extracts demonstrated similar antibacterial susceptibility towards Gram-positive ( Bacillus subtilis and Staphylococcus aureus), while showing little to no activity against Gram-negative bacteria ( Escherichia coli and Pseudomonas aeruginosa). Among a range of pharmaceutically relevant solvents tested, UA was only soluble in ethanol (at concentrations up to 1–2 mg mL −1 ). |
format |
Article in Journal/Newspaper |
author |
Ahmad, Rafi Borowiec, Paulina Falck-Ytter, Anne Bergljot Strætkvern, Knut Olav |
spellingShingle |
Ahmad, Rafi Borowiec, Paulina Falck-Ytter, Anne Bergljot Strætkvern, Knut Olav Extraction, Solubility and Antimicrobial Activity of (-) Usnic Acid in Ethanol, a Pharmaceutically Relevant Solvent |
author_facet |
Ahmad, Rafi Borowiec, Paulina Falck-Ytter, Anne Bergljot Strætkvern, Knut Olav |
author_sort |
Ahmad, Rafi |
title |
Extraction, Solubility and Antimicrobial Activity of (-) Usnic Acid in Ethanol, a Pharmaceutically Relevant Solvent |
title_short |
Extraction, Solubility and Antimicrobial Activity of (-) Usnic Acid in Ethanol, a Pharmaceutically Relevant Solvent |
title_full |
Extraction, Solubility and Antimicrobial Activity of (-) Usnic Acid in Ethanol, a Pharmaceutically Relevant Solvent |
title_fullStr |
Extraction, Solubility and Antimicrobial Activity of (-) Usnic Acid in Ethanol, a Pharmaceutically Relevant Solvent |
title_full_unstemmed |
Extraction, Solubility and Antimicrobial Activity of (-) Usnic Acid in Ethanol, a Pharmaceutically Relevant Solvent |
title_sort |
extraction, solubility and antimicrobial activity of (-) usnic acid in ethanol, a pharmaceutically relevant solvent |
publisher |
SAGE Publications |
publishDate |
2017 |
url |
http://dx.doi.org/10.1177/1934578x1701200725 http://journals.sagepub.com/doi/pdf/10.1177/1934578X1701200725 |
genre |
Reindeer lichen |
genre_facet |
Reindeer lichen |
op_source |
Natural Product Communications volume 12, issue 7, page 1934578X1701200 ISSN 1934-578X 1555-9475 |
op_rights |
http://journals.sagepub.com/page/policies/text-and-data-mining-license |
op_doi |
https://doi.org/10.1177/1934578x1701200725 |
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Natural Product Communications |
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12 |
container_issue |
7 |
container_start_page |
1934578X1701200 |
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1810473997130792960 |