
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/">
  <dc:description xml:lang="eng">This study investigated the application of deep eutectic solvents (DESs) for extracting polyphenols from
Hypericum androsaemum, a plant valued for its culinary, cosmetic, and pharmacological potential,
particularly for its hepatoprotective, anti-inflammatory, and diuretic properties. The research explored
a green approach using various DESs based on betaine and lactic acid, including betaine/ethylene
glycol (Bet/Eg), betaine/glycerol (Bet/Gly), lactic acid/menthol (La/Men), lactic acid/proline (La/Pro),
lactic acid/glucose (La/Glu), and lactic acid-betaine (La/Bet). These DESs were employed in ultrasonic
extraction at varying temperatures (30, 45, and 60°C) and extraction times (30 and 60 minutes), with
conventional solvents ethanol and water used as control. The extracted polyphenols were analyzed
using HPLC and assessed for antibacterial activity against both Gram-negative and Gram-positive
bacteria, including Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus
aureus. Chlorogenic acid was the most abundant compound, with concentrations ranging from 16.90
to 796.99 μg/mL, peaking in the La/Glu extract obtained at 60°C for 60 minutes and in the Bet/
Eg extract obtained at 60°C for 30 minutes (767.84 μg/mL). Other identified compounds included
hyperoside, quercetin, quercitrin, and isoquercitrin. The Bet/Eg system at 60°C for 30 minutes was
particularly effective in extracting hyperoside, quercitrin, and isoquercitrin, while the La/Glu extract
at 60°C for 60 minutes favored quercetin recovery. Although water demonstrated similar efficiency
to the most effective DESs for extracting chlorogenic acid, its efficiency for other polyphenols was
significantly lower. In terms of antibacterial activity of selected extracts, water extracts showed the
weakest activity despite high chlorogenic acid content, with minimum inhibitory concentrations
(MICs) of 12.500-25.000 mg/mL. The La/Glu extracts exhibited more pronounced antibacterial
activity, particularly against Gram-positive bacteria (MICs of 0.391 and 0.781 mg/mL for Gram-positive
and Gram-negative bacteria, respectively). The most potent antibacterial activity was observed in the
Bet/Eg extracts at 60°C for 60 minutes, with MICs of 0.195 mg/mL against B. subtilis and S. aureus
and 0.012 mg/mL against E. coli and P. aeruginosa. This study highlights the effectiveness of DESs in
enhancing the extraction of bioactive compounds from H. androsaemum, presenting a promising
green alternative for obtaining extracts rich in high-value polyphenols with significant antibacterial
properties. These findings have potential applications in the food, pharmaceutical, and cosmetic
industries.</dc:description>
  <dc:date>2024</dc:date>
  <dc:subject xml:lang="eng">antibacterial activity, deep eutectic system, Hypericum androsaemum, phenols</dc:subject>
  <dc:source>BOOK OF ABSTRACTS</dc:source>
  <dc:source>number: CO14</dc:source>
  <dc:source>startpage: 89</dc:source>
  <dc:source>endpage: 89</dc:source>
  <dc:creator>Vladić, Jelena</dc:creator>
  <dc:creator id="https://orcid.org/0000-0002-9684-2637">Živković, Jelena</dc:creator>
  <dc:creator>Pavić, Valentina</dc:creator>
  <dc:creator id="https://orcid.org/0000-0002-2086-9593">Šavikin, Katarina</dc:creator>
  <dc:creator>Kovačević, Strahinja</dc:creator>
  <dc:creator>Jokić, Stela</dc:creator>
  <dc:creator>Duarte, Ana Rita</dc:creator>
  <dc:type>info:eu-repo/semantics/conferenceProceedings</dc:type>
  <dc:rights>All rights reserved</dc:rights>
  <dc:title xml:lang="eng">EVALUATION OF DEEP EUTECTIC SOLVENTS FOR ENHANCED POLYPHENOL EXTRACTION AND ANTIBACTERIAL ACTIVITY OF Hypericum androsaemum EXTRACTS</dc:title>
  <dc:language>eng</dc:language>
  <dc:format>application/pdf</dc:format>
  <dc:format>429203 bytes</dc:format>
  <dc:identifier>https://unilib.phaidrabg.rs/o:6498</dc:identifier>
  <dc:identifier>ISSN: 3044-2117</dc:identifier>
</oai_dc:dc>