Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
7.4
4.2
Journals
Molecules
Special Issues
Conventional and Emerging Extraction Techniques for Compounds from Natural Source...
molecules-logo
Submit to Molecules Review for Molecules Propose a Special Issue

Journal Menu

► Journal Menu

Journal Browser

► Journal Browser
share announcement

Conventional and Emerging Extraction Techniques for Compounds from Natural Source and Food: 2nd Edition

A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Natural Products Chemistry".

Deadline for manuscript submissions: closed (30 September 2024) | Viewed by 10740

Special Issue Editor

Dr. Branimir Pavlic

E-Mail Website
Guest Editor
Faculty of Technology Novi Sad, University of Novi Sad, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia
Interests: process engineering; statistical modeling; antioxidant activity; natural product chemistry; extraction; food chemistry
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The potential of natural resources and food (main and side streams) to create new opportunities for the isolation of high-value products has been underestimated and not thoroughly explored. However, the valorization of by-products and waste streams through the recovery of its valuable bioactive compounds has been recognized as an important method for increasing sustainability in production in order to create new opportunities on the market. The main issues associated with common valorization approaches of natural resources include the disadvantages and limitations of traditional extraction procedures that do not satisfy the economic aspects of production in terms of energy and resource preservation and improved yield and quality of the obtained extracts. Recent studies have suggested that novel extraction techniques could address several major challenges associated with conventional techniques and procedures. The main aim of their utilization is to achieve a reduction in energy and time consumption and, at the same time, to improve the extraction yield and quality of the extract. The traditional approach implies applications of organic solvents, which are followed by major issues in terms of poor selectivity towards certain bioactives, high price and tremendous environmental and human toxicity. Strong scientific evidence supporting the efficiency of emerging extraction techniques for the production of high-quality extracts with improved bioactivity suggests that different applications need to be explored urgently. The main focus of this Special Issue is the investigation of conventional and novel extraction techniques as efficient tools for the isolation of bioactive compounds from natural resources. This Special Issue is open to all high-quality contributions aimed at the development of innovative concepts for extracting bioactive compounds by applications following traditional and emerging techniques:

  • Conventional solid–liquid extraction;
  • Soxhlet extraction;
  • Hydrodistillation;
  • Ultrasound-assisted extraction;
  • Microwave-assisted extraction;
  • Supercritical fluid extraction;
  • Pressurized-liquid and subcritical water extraction;
  • Enzyme-assisted processes;
  • Extraction with natural deep eutectic solvents, etc.

Dr. Branimir Pavlic
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Molecules is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • convectional extraction techniques
  • ultrasound-assisted extraction
  • microwave-assisted extraction
  • high-pressure processes
  • NADES extraction
  • bioactive compounds

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue policies can be found here.

Related Special Issue

Published Papers (5 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

23 pages, 6992 KiB  
Article
Ultrasound as Green Technology for the Valorization of Pumpkin Leaves: Intensification of Protein Recovery
by Jelena Mijalković, Nataša Šekuljica, Sonja Jakovetić Tanasković, Predrag Petrović, Bojana Balanč, Marija Korićanac, Ana Conić, Jelena Bakrač, Verica Đorđević, Branko Bugarski and Zorica Knežević-Jugović
Molecules 2024, 29(17), 4027; https://doi.org/10.3390/molecules29174027 - 26 Aug 2024
Cited by 3 | Viewed by 2075
Abstract
The recovery of valuable nutritional compounds, like proteins, from waste streams and by-products is a key strategy for enhancing production sustainability and opening up new market potential. This research aimed to use high-intensity ultrasound as an innovative technique to extract the soluble proteins [...] Read more.
The recovery of valuable nutritional compounds, like proteins, from waste streams and by-products is a key strategy for enhancing production sustainability and opening up new market potential. This research aimed to use high-intensity ultrasound as an innovative technique to extract the soluble proteins from the pumpkin leaves. The impact of various sonication amplitudes and duration periods on protein yield, functional properties, antioxidant qualities, and structural characteristics, were studied. Utilization of ultrasound technology significantly increased the yield of pumpkin leaf protein by up to 40%—six times higher than maceration. The ultrasound extraction provided a RuBisCO-rich protein fraction with high radical scavenging and chelating activities, especially at 40% amplitude. Cavitation modified the tertiary and secondary structures of leaf proteins: the amount of α-helix changed based on amplitude (12.3–37.7%), the amount of random coil increased to 20.4%, and the amount of β-turn reduced from 31 to 18.6%. The alteration of the protein fluorescence spectrum (blue shift in spectrum) provides further evidence that ultrasound alters the proteins’ molecular structure in comparation with maceration; the maximum tryptophan fluorescence intensity decreased from 22.000 to 17.096. The hydrophobicity values of 76.8–101.5 were substantially higher than the maceration value of 53.4, indicating that ultrasound improved the hydrophobicity of protein surfaces. Ultrasound resulted in a significant increase in solubility in an acidic environment with the increase in sonication amplitude. A 2.4-fold increase in solubility at pH 2 becomes apparent (20% amplitude; 43.1%) versus maceration (18.2%). The emulsifying ability decreases from 6.62 to 5.13 m2/g once the sonication amplitude increases by 20–70%. By combining the ultrasound periods and amplitudes, it is possible to create high-value protein leaf extracts with improved properties which can find real application as food additives and dietary supplements. Full article
(This article belongs to the Special Issue Conventional and Emerging Extraction Techniques for Compounds from Natural Source and Food: 2nd Edition)
►▼ Show Figures

Figure 1

19 pages, 1985 KiB  
Article
Valorization of Sour Cherry Kernels: Extraction of Polyphenols Using Natural Deep Eutectic Solvents (NADESs)
by Danica Božović, Ivana Dimić, Nemanja Teslić, Aleksandra Mišan, Milica Pojić, Alena Stupar, Anamarija Mandić, Sanja Milošević, Zoran Zeković and Branimir Pavlić
Molecules 2024, 29(12), 2766; https://doi.org/10.3390/molecules29122766 - 11 Jun 2024
Cited by 2 | Viewed by 1376
Abstract
The objective of this research was to optimize the natural deep eutectic solvent (NADES) extraction process from sour cherry kernels (Prunus cerasus L.). For polyphenol isolation, conventional solid–liquid extraction was employed using different concentrations of ethanol (0, 10, 20, 30, 40, 50, [...] Read more.
The objective of this research was to optimize the natural deep eutectic solvent (NADES) extraction process from sour cherry kernels (Prunus cerasus L.). For polyphenol isolation, conventional solid–liquid extraction was employed using different concentrations of ethanol (0, 10, 20, 30, 40, 50, 60, 70, 80, 90, and 96%), as well as the innovative NADES extraction technique. In the initial phase of the research, a screening of 10 different NADESs was conducted, while extraction was carried out under constant parameters (50 °C, 1:20 w/w, 60 min). NADES 4, composed of lactic acid and glucose in a molar ratio of 5:1, exhibited the highest efficiency in the polyphenol isolation. In the subsequent phase of the research, response surface methodology (RSM) was utilized to optimize the extraction process. Three independent variables, namely temperature, extraction time, and solid–liquid (S/L) ratio, were examined at three different levels. The extracted samples were analyzed for total phenol (TP) and antioxidant activity using the DPPH, ABTS, and FRAP assays. ANOVA and descriptive statistics (R2 and CV) were performed to fit the applied model. According to RSM, the optimal extraction conditions were determined as follows: temperature of 70 °C, extraction time of 161 min, and S/L ratio of 1:25 w/w. Full article
(This article belongs to the Special Issue Conventional and Emerging Extraction Techniques for Compounds from Natural Source and Food: 2nd Edition)
►▼ Show Figures

Figure 1

14 pages, 3601 KiB  
Article
Response Surface Optimization for Water-Assisted Extraction of Two Saponins from Paris polyphylla var. yunnanensis Leaves
by Yutian Jin, Qing Qiao, Linmei Dong, Mokun Cao, Ping Li, Aizhong Liu and Rui Sun
Molecules 2024, 29(7), 1652; https://doi.org/10.3390/molecules29071652 - 6 Apr 2024
Cited by 2 | Viewed by 1917
Abstract
The process of extracting polyphyllin II and polyphyllin VII by water-assisted extraction was established and optimized in this study. Response surface methodology was used to establish a prediction model to optimize the extraction conditions. Based on the one-way test, the Box–Behnken design with [...] Read more.
The process of extracting polyphyllin II and polyphyllin VII by water-assisted extraction was established and optimized in this study. Response surface methodology was used to establish a prediction model to optimize the extraction conditions. Based on the one-way test, the Box–Behnken design with three factors and three levels was used for the experimental program, and the composition analysis was carried out by high-performance liquid chromatography (HPLC). The optimal extraction conditions for polyphyllin II and polyphyllin VII were as follows: extraction time of 57 and 21 min, extraction temperature of 36 and 32 °C, solid-to-liquid ratio of 1:10 and 1:5 g/mL, respectively, and the yields of polyphyllin II and polyphyllin VII were 1.895 and 5.010%, which was similar to the predicted value of 1.835 and 4.979%. The results of the ANOVA showed that the model fit was good, and the Box–Behnken response surface method could optimize the water-assisted extraction of saponins from the leaves of Paris polyphylla var. yunnanensis. This study provides a theoretical basis for the application of polyphyllin II and polyphyllin VII in pharmaceutical production. Full article
(This article belongs to the Special Issue Conventional and Emerging Extraction Techniques for Compounds from Natural Source and Food: 2nd Edition)
►▼ Show Figures

Graphical abstract

17 pages, 4655 KiB  
Article
Structural Characterization and Antioxidant Activity of β-Glucans from Highland Barley Obtained with Ultrasonic–Microwave-Assisted Extraction
by Lihua Chen, Chunfeng Cui, Zhiheng Wang, Fuhong Che, Zhanxiu Chen and Shengbao Feng
Molecules 2024, 29(3), 684; https://doi.org/10.3390/molecules29030684 - 1 Feb 2024
Cited by 4 | Viewed by 2265
Abstract
In order to efficiently extract β-glucan from highland barley (HBG) and study its structural characterization and antioxidant activity, ultrasonic–microwave-assisted extraction (UME) was optimized by the response surface method (RSM). Under the optimal extraction conditions of 25.05 mL/g liquid–solid ratio, 20 min ultrasonic time, [...] Read more.
In order to efficiently extract β-glucan from highland barley (HBG) and study its structural characterization and antioxidant activity, ultrasonic–microwave-assisted extraction (UME) was optimized by the response surface method (RSM). Under the optimal extraction conditions of 25.05 mL/g liquid–solid ratio, 20 min ultrasonic time, and 480 W microwave intensity, the DPPH radical scavenging activity of HBG reached 25.67%. Two polysaccharide fractions were purified from HBG, namely HBG-1 and HBG-2. Structural characterization indicated that HBG-1 and HBG-2 had similar functional groups, glycosidic linkages, and linear and complex chain conformation. HBG-1 was mainly composed of glucose (98.97%), while HBG-2 primarily consisted of arabinose (38.23%), galactose (22.01%), and xylose (31.60%). The molecular weight of HBG-1 was much smaller than that of HBG-2. Both HBG-1 and HBG-2 exhibited concentration-dependent antioxidant activity, and HBG-1 was more active. This study provided insights into the efficient extraction of HBG and further investigated the structure and antioxidant activities of purified components HBG-1 and HBG-2. Meanwhile, the results of this study imply that HBG has the potential to be an antioxidant in foods and cosmetics. Full article
(This article belongs to the Special Issue Conventional and Emerging Extraction Techniques for Compounds from Natural Source and Food: 2nd Edition)
►▼ Show Figures

Graphical abstract

15 pages, 3028 KiB  
Article
Natural Deep Eutectic Solvents for the Extraction of Spilanthol from Acmella oleracea (L.) R.K.Jansen
by Fabian Alperth, Theresa Feistritzer, Melanie Huber, Olaf Kunert and Franz Bucar
Molecules 2024, 29(3), 612; https://doi.org/10.3390/molecules29030612 - 27 Jan 2024
Cited by 2 | Viewed by 2209
Abstract
With a growing focus on green chemistry, the extraction of natural products with natural deep eutectic solvents (NADES), which are eutectic mixtures of hydrogen bond donors and acceptors, has become an ever-expanding field of research. However, the use of NADES for the extraction [...] Read more.
With a growing focus on green chemistry, the extraction of natural products with natural deep eutectic solvents (NADES), which are eutectic mixtures of hydrogen bond donors and acceptors, has become an ever-expanding field of research. However, the use of NADES for the extraction of spilanthol from Acmella oleracea (L.) R.K.Jansen has not yet been investigated. Therefore, in this study, 20 choline chloride-based NADES, and for comparison, ethanol, were used as green extraction agents for spilanthol from Acmella oleracea flower heads. The effects of time, water addition, and temperature on NADES extractions were investigated and analysed by HPLC-DAD quantification. Additionally, UHPLC-DAD-ESI-MSn results for dichloromethane extracts, as well as the isolation of spilanthol and other main constituents as reference compounds, are reported. The best green extraction results were achieved by choline chloride (ChCl) with 1,2-propanediol (P, 1:2 molar ratio, +20% water) at 244.58 µg/mL, comparable to yields with ethanol (245.93 µg/mL). Methylurea (MeU, 1:2, +20% water) also showed promising results as a hydrogen bond donor in combination with choline chloride (208.12 µg/mL). In further experiments with NADES ChCl/P (1:2) and ChCl/MeU (1:2), extraction time had the least effect on spilanthol extraction with NADES, while yield decreased with water addition over 20% and increased with extraction temperature up to 80 °C. NADES are promising extraction agents for the extraction of spilanthol, and these findings could lead to applicable extracts for medicinal purposes, due to their non-toxic constituents. Full article
(This article belongs to the Special Issue Conventional and Emerging Extraction Techniques for Compounds from Natural Source and Food: 2nd Edition)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-5
Back to TopTop