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Cited by 31Phytochemicals and Antioxidant ActivitiesIonic liquids properties and applicationsAgricultural and Biological Research

The DOI matches its Crossref record; 45 of the 45 references it cites were found in a registry or an index.

Ultrasound-Assisted Extraction of Polyphenols from Maritime Pine Residues with Deep Eutectic Solvents

Open access
Duarte, Hugo, Gomes, Valentim, Aliaño-González, María José, Faleiro, Leonor, Romano, Anabela, Medronho, Bruno·2022·Foods
DOI 10.3390/foods11233754PMC PMC9738461
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Abstract

Deep eutectic solvents represent an important alternative in the field of green solvents due to their low volatility, non-toxicity, and low synthesis cost. In the present investigation, we propose the production of enriched polyphenolic extracts from maritime pine forest residues via an ultrasound-assisted approach. A Box–Behnken experimental design with a response surface methodology was used with six variables to be optimized: solid-to-solvent ratio, water percentage, temperature and time of extraction, amplitude, and catalyst concentration. The mixture of levulinic and formic acids achieved the highest extraction yield of polyphenols from pine needle and bark biomass. In addition, the solid-to-solvent ratio was found to be the only influential variable in the extraction (p-value: 0.0000). The optimal conditions were established as: 0.1 g of sample in 10 mL of LA:FA (70:30%, v/v) with 0% water and 0 M H2SO4 heated to 30 °C and extracted during 40 min with an ultrasound amplitude of 80% at 37 kHz. The bioactive properties of polyphenol-enriched extracts have been proven with significant antioxidant (45.90 ± 2.10 and 66.96 ± 2.75 mg Trolox equivalents/g dw) and antimicrobial activities. The possibility to recycle and reuse the solvent was also demonstrated; levulinic acid was successfully recovered from the extracts and reused in novel extractions on pine residues. This research shows an important alternative to obtaining polyphenol-enriched extracts from forest residues that are commonly discarded without any clear application, thus opening an important window toward the valorization of such residues.

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Crossref · 10.3390/foods11233754

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Figure 1 Total polyphenols concentration (mg/g dw) for P. pinaster (A) needles and (B) bark according to the different DES mixtures and chemical solvents used for the extraction. Solvent acronyms have been defined in the experimental section. Different letters indicate significant differences in the ANOVA Duncan post hoc test with 95% of confidence.
Figure 1 Total polyphenols concentration (mg/g dw) for P. pinaster (A) needles and (B) bark according to the different DES mixtures and chemical solvents used for the extraction. Solvent acronyms have been defined in the experimental section. Different letters indicate significant differences in the ANOVA Duncan post hoc test with 95% of confidence.CC BY · PubMed Central
Figure 2 Pareto chart results from the total polyphenols extracted (mg/g dw) from pine needles using USE: A: solid-to-solvent ratio (g sample in 10 mL solvent); B: water (%) in solvent; C: temperature of extraction (°C); D: time of extraction (h); E: amplitude (%); F: catalyst concentration of H2SO4 (M). The vertical line marks 95% of confidence.
Figure 2 Pareto chart results from the total polyphenols extracted (mg/g dw) from pine needles using USE: A: solid-to-solvent ratio (g sample in 10 mL solvent); B: water (%) in solvent; C: temperature of extraction (°C); D: time of extraction (h); E: amplitude (%); F: catalyst concentration of H2SO4 (M). The vertical line marks 95% of confidence.CC BY · PubMed Central
Figure 3 Pareto chart results from the total polyphenols extracted (mg/g dw) from pine needles using factorial design, A: solid-to-solvent ratio (g sample in 10 mL solvent); B: time of extraction (minutes). The vertical line marks 95% of confidence.
Figure 3 Pareto chart results from the total polyphenols extracted (mg/g dw) from pine needles using factorial design, A: solid-to-solvent ratio (g sample in 10 mL solvent); B: time of extraction (minutes). The vertical line marks 95% of confidence.CC BY · PubMed Central
Figure 4 Antimicrobial activity of the extracts from pine needle and bark residues obtained under optimal extraction conditions.
Figure 4 Antimicrobial activity of the extracts from pine needle and bark residues obtained under optimal extraction conditions.CC BY · PubMed Central

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Research works printed but not linked: 1

  1. Boddula, R., Ahamed, M.I., and Asiri, A.M. (2021). Chapter 14—Green Approaches for the Extraction of Bioactive from Natural Sources for Pharmaceutical Applications. Green Sustainable Process for Chemical and Environmental Engineering and Science, Elsevier.

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Metadata

Authors
Duarte, H., Gomes, V., Aliaño-González, M. J., Faleiro, L., Romano, A., & Medronho, B.
Affiliations
  • University of Algarve (PT)
  • MED—Mediterranean Institute for Agriculture, Environment and Development, Faculdade de Ciências e Tecnologia, Campus de Gambelas, Universidade do Algarve, Ed. 8, 8005-139 Faro, Portugal
  • Champalimaud Research Program, Champalimaud Centre for the Unknown, 1400-038 Lisbon, Portugal
  • Mid Sweden University (SE)
Corresponding author
Medronho, Bruno
ORCID
Venue
Foods
Publisher
MDPI AG
Published
2022-11-22
Volume
11
Issue
23
Pages
3754
ISSN
2304-8158 (ISSN-L)
DOI
10.3390/foods11233754
PMC
PMC9738461
OpenAlex
W4309592940
Cited by
31
References
44
Citations by year
2026: 8 · 2025: 10 · 2024: 5 · 2023: 8
FWCI
3.01
Type
journal article
Language
en
Open access
Licence
Locations
  • Foods (publishedVersion, cc-by)
  • PubMed Central (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • RODIN (Universidad de Cádiz) (publishedVersion, cc-by)
  • DOAJ (DOAJ: Directory of Open Access Journals) (submittedVersion, cc-by-sa)
  • Portuguese National Funding Agency for Science, Research and Technology (RCAAP Project by FCT) (submittedVersion, cc-by)
Funders
  • National Funds (UIDB/05183/2020, PTDC/ASP-SIL/30619/2017, CEECIND/01014/2018)
  • FCT—Foundation for Science and Technology (UIDB/05183/2020, PTDC/ASP-SIL/30619/2017, CEECIND/01014/2018)
  • researcher (UIDB/05183/2020, PTDC/ASP-SIL/30619/2017, CEECIND/01014/2018)
Topics
  • Health Sciences › Medicine › Biochemistry (medical) › Phytochemicals and Antioxidant Activities
  • Physical Sciences › Chemistry › Physical and Theoretical Chemistry › Ionic liquids properties and applications
  • Life Sciences › Agricultural and Biological Sciences › Food Science › Agricultural and Biological Research
Keywords
ultrasound-assisted extraction, polyphenols, deep eutectic solvents, levulinic acid, formic acid, pine needles, pine bark, biomass valorization, antioxidant activity, antimicrobial activity, solvent recovery, extraction optimization

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