Submit to Topical Collection Review for Separations

Journal Menu

Journal Browser

Recent Trends in the Separation of Natural Products and Pharmaceuticals

Print Collection Flyer
Collection Editors
Collection Information
Keywords
Published Papers

A topical collection in Separations (ISSN 2297-8739). This collection belongs to the section "Analysis of Natural Products and Pharmaceuticals".

Viewed by 23282

Share This Topical Collection

Editors

Dr. Paraskevas D. Tzanavaras

E-Mail Website
Collection Editor

Laboratory of Analytical Chemistry, School of Chemistry, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
Interests: automation; sequential injection analysis; separation techniques (HPLC, CE); post-column derivatization; microextraction
Special Issues, Collections and Topics in MDPI journals

Prof. Dr. Susanne K. Wiedmer

E-Mail Website
Collection Editor

Department of Chemistry, University of Helsinki (UH), Helsinki, Finland
Interests: capillary electrophoresis; capillary liquid chromatography; physico-chemical characterization; cytotoxicity; liposomes; ionic liquids
Special Issues, Collections and Topics in MDPI journals

Topical Collection Information

Dear Colleagues,

In general terms, “natural products” can be defined as compounds that are synthesized/produced by living organisms (plants, animals, etc.). The importance of natural products has been recognized for thousands of years, and a considerable proportion of new drugs are still based on the discovery of natural biogenic molecules.

In the Topical Collection on “Recent Trends in the Separation of Natural Products and Pharmaceuticals”, we welcome original research and review articles on the development and application of analytical separation technologies to both natural product and pharmaceutical sciences.

Research on the analysis and separation of natural products should ideally increase the current knowledge on the extraction, separation, isolation, identification, structure elucidation, and quantification of bioactive compounds. All aspects of instrumental analytical separation and analysis methodologies that can be used as a tool to achieve these tasks are welcome. Reports on the quality control and standardization of natural products will also be considered on the basis of their significance in the field.

Analysis of pharmaceuticals, on the other hand, is an extremely broad topic ranging from quality control or raw materials to the impurity profiling of active ingredients and to bioanalytical applications. Original work on all aspects of related research is welcome. Impurity profiling and especially the identification/quantification of genotoxic impurities are of particular interest, while simple assays using HPLC should provide clear advantages from an analytical point of view to be processed further. Research work from industries reporting results from real-world analytical problems is also warmly welcome. All pharmaceutical-related analytical methods should be fully validated.

Bioanalytical methods including pharmacokinetic, bioequivalence, protein, and DNA-binding studies are welcome on the basis of analytical novelty, including sample preparation. Real-world applications (endogenous analytes or sampling from patients) are highly recommended versus demonstration through the spiking of blank biological matrices.

In all cases, novelty will be the major suitability criterion of submitted articles. Authors must therefore always address the question of how their proposed methodology compares with previously reported methods. We look forward many interesting submissions!

Dr. Paraskevas D. Tzanavaras
Prof. Dr. Susanne K. Wiedmer
Collection Editors

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 collection 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. Separations is an international peer-reviewed open access monthly 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 2600 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

natural products
pharmaceuticals
automation
sequential injection analysis
separation techniques (HPLC, CE)
post-column derivatization
microextraction

Published Papers (9 papers)

Download All Papers

2024

Jump to: 2023, 2022, 2021

13 pages, 2509 KiB

Open AccessArticle

Exploratory Study on Distinguishing Dendrobium Stem and Five Species of Dendrobium Using Heracles Neo Ultra-Fast Gas Phase Electronic Nose

by Yuping Dai, Dan Huang, Ye He, Yun Xiang and Shunxiang Li

Separations 2024, 11(7), 211; https://doi.org/10.3390/separations11070211 - 10 Jul 2024

Viewed by 728

Abstract

Dendrobium stem is a valuable food with medicinal and edible properties. Due to its high medicinal value and price, closely related Dendrobium varieties are often sold as imitations on the market. Therefore, there is an urgent need to develop new methods that can quickly identify Dendrobium stem and its closely related species. The Heracles Neo ultra-fast gas phase electronic nose was used in this study to determine and analyze the composition and contents of volatile organic compounds (VOCs) in Dendrobium stem and samples of five other species closely related to it. A total of 20 VOCs were identified, and a fingerprint map of the VOCs was constructed. Principal component analysis (PCA), Euclidean distance, and other methods were used to comprehensively process and analyze the obtained VOC information. The AroChemBase database was also used for qualitative analysis of the compounds. The results showed that there are significant differences in the odor fingerprint spectra of Dendrobium stem and the five other closely related species. The main types of compounds in Dendrobium stem and its five closely related species were organic esters, aldehydes, ketones, and olefins. Among them, 3-methylbutanal and n-butanol were characteristic compounds of the Dendrobium stem sample, while the VOCs acetonitrile and trometamol were present in the five related Dendrobium species samples. The Heracles Neo ultra-fast gas phase electronic nose can quickly and accurately identify Dendrobium stem and its five closely related species. It can also be used for the quality evaluation of Dendrobium stem, providing a theoretical reference for reducing the phenomenon of medicinal confusion in the Dendrobium stem market. Full article

► Show Figures

Figure 1

2023

Jump to: 2024, 2022, 2021

13 pages, 1495 KiB

Open AccessArticle

Programmable Low-Pressure Chromatographic Sub-90 s Assay of Parabens in Cosmetics with Post-Column Chemiluminescence Detection

by Margarita Barbatsi and Anastasios Economou

Separations 2023, 10(6), 350; https://doi.org/10.3390/separations10060350 - 11 Jun 2023

Cited by 1 | Viewed by 1474

Abstract

This work describes a new programmable low-pressure chromatography method with post-column chemiluminescence (CL) detection for the rapid and cost-effective determination of four parabens in cosmetic products. Elution of the target analytes was achieved using a programmable mobile phase prepared by implementing a linear solvent gradient protocol based on appropriate flow rate modulation of 2 MilliGAT pumps. A 5 mm monolithic C18 column was used to separate the parabens. Post-column reaction of the eluted parabens with an acidic Ce(IV)-rhodamine 6G (Rho 6G) medium was carried out by introducing a flow stream of the reactants into the column eluate. The light generated from the CL reaction was detected with a flow-through CL detector fabricated in-house. The whole sequence of operations (including sample injection, generation of the mobile phase, addition of the post-column reaction reagents and signal acquisition) was under full computer control. Various operational parameters (the mobile phase composition and gradient conditions, the CL reagents’ concentrations and flow rates and the length of the reaction coil) were studied. The method was validated and applied to the analysis of various cosmetic products. The proposed approach allows sub-90 s separation of the four parabens and their determination with a limit of quantification of 0.2 μg L⁻¹ with a sample throughput of 24 samples h⁻¹. In addition, the method is economical, makes use of low-cost low-pressure components, is fully automated and produces a low amount of waste. Full article

► Show Figures

Graphical abstract

14 pages, 1761 KiB

Open AccessArticle

Quantification of Health Claim-Relevant Tyrosol and Hydroxytyrosol after Direct Hydrolysis Improves Customer Understanding and Mitigates Market Distortion

by Alex Mair, Martin Fischnaller, Oliver M. D. Lutz, Danilo Corradini, Alexios-Leandros Skaltsounis, Panagiotis Stathopoulos, Thomas A. E. Jakschitz, Matthias Rainer and Günther K. Bonn

Separations 2023, 10(4), 268; https://doi.org/10.3390/separations10040268 - 21 Apr 2023

Viewed by 1888

Abstract

The EFSA-approved claim that olive oil is beneficial for cardiovascular health suffers from ambiguities that lead to a vague and potentially subjective interpretation of the underlying analytical data. Misunderstandings among customers, but also market distortions are possible consequences. In this study, a rapid and simple analytical technique is presented that circumvents the ambiguity by measuring levels of putative health-promoting compounds as the equivalent of tyrosol and hydroxytyrosol, cleaving such moieties from more complex constituents such as oleuropein and oleocanthal. Since the direct hydrolysis of the olive oil is the central element of the process, the reaction temperature, time, reagent concentration and reagent type were optimized. In addition, the influence of co-solvents, which might support the intermittent miscibility of the two phases during hydrolysis, was investigated. The analytical and economic implications are discussed particularly in the context of a commonly used technique. Full article

► Show Figures

Figure 1

2022

Jump to: 2024, 2023, 2021

23 pages, 1592 KiB

Open AccessReview

Extraction, Separation, Antitumor Effect, and Mechanism of Alkaloids in Sophora alopecuroides: A Review

by Ruixia Zhang, Ruizhou Wang, Shipeng Zhao, Dan Chen, Fusheng Hao, Bo Wang, Jin Zhang, Yingying Ma, Xingyi Chen, Xiaojuan Gao, Lu Han and Changcai Bai

Separations 2022, 9(11), 380; https://doi.org/10.3390/separations9110380 - 20 Nov 2022

Cited by 4 | Viewed by 2247

Abstract

Malignant tumors pose a serious threat to human health, reducing quality of life. Natural antitumor drugs play a vital role in the treatment of cancer. Sophora alopecuroides, a traditional Chinese medicine not a part of the Chinese Pharmacopoeia, grows in the arid desert and edge zone of grassland. Previous studies have extensively investigated the antitumor effects of S. alopecuroides and its major alkaloids. Of these, aloperine, matrine, oxymatrine, sophoridine, and sophocarpine have received the most attention. In recent years, a variety of extraction and separation methods have been applied to the study of the alkaloids of Sophora alopecuroides, which has greatly promoted the study of the chemical constituents and pharmacological activities of the plant. S. alopecuroides has been shown to impede cancer cell growth, induce cell cycle arrest, enhance apoptosis and cellular differentiation, and impede cancer metastasis and invasion. Several mechanisms have been proposed for modulating cancer signaling and molecular pathways or targets based on multitudinous studies in various types of cancerous cells. This review provides an in-depth overview of the antitumor effects of S. alopecuroides and the potential targets of 12 alkaloids in S. alopecuroides via a pharmacophore mapping approach and offers a scientific basis for the further exploration of the mechanism related to the antitumor effects of this plant. Full article

► Show Figures

Figure 1

17 pages, 3129 KiB

Open AccessArticle

Separation and Purification of Taxanes from Crude Taxus cuspidata Extract by Antisolvent Recrystallization Method

by Yajing Zhang, Zirui Zhao, Wenlong Li, Yuanhu Tang, Huiwen Meng and Shujie Wang

Separations 2022, 9(10), 304; https://doi.org/10.3390/separations9100304 - 11 Oct 2022

Cited by 5 | Viewed by 2853

Abstract

Taxanes are natural compounds with strong antitumor activity. In this study, we first enriched taxanes by ultrasonic extraction and liquid–liquid extraction from Taxus cuspidata, then purified these taxanes by the antisolvent recrystallization method, and discussed the effects of four recrystallization conditions on the purity of eight target compounds. The most promising purification results were obtained using methanol as a solvent and water as an antisolvent. Response surface methodology (RSM) was used to further optimize the optimal purification conditions: when the crude extraction concentration was 555.28 mg/mL, an antisolvent to solvent volume ratio was 28.16 times, the deposition temperature was 22.91 °C, and the deposition time was 1.76 min, the purity of the taxanes reached its maximum. The scanning electron microscopy (SEM) results showed that recrystallization could effectively reduce the particle size of crude Taxus cuspidata and control the particle morphology. X-ray diffraction (XRD) and Raman spectrum experiments demonstrated that the amorphous state of the crude Taxus cuspidata did not change during the recrystallization process, and always remained amorphous. This recrystallization method can effectively improve the purity of taxanes in Taxus cuspidata, and is suitable for the preliminary purification of taxanes. Full article

► Show Figures

Figure 1

41 pages, 4964 KiB

Open AccessReview

Lycium Genus Polysaccharide: An Overview of its Extraction, Structures, Pharmacological Activities and Biological Applications

by Bo Wang, Lu Han, Jun-Mei Liu, Jin Zhang, Wen Wang, Bing-Ge Li, Cai-Xia Dong and Chang-Cai Bai

Separations 2022, 9(8), 197; https://doi.org/10.3390/separations9080197 - 30 Jul 2022

Cited by 9 | Viewed by 3654

Abstract

Polysaccharide is considered to be the main active ingredient of the genus Lycium L., which is taken from the dried fruit of the famous Chinese herbal medicine and precious tonic known as wolfberry. Traditional uses include nourishing the liver and kidney and improving eyesight, with widespread use in the clinical practice of traditional Chinese medicine. Many studies have focused on the isolation and identification of the genus Lycium L. polysaccharide and its biological activities. However, the variety of raw materials and the mechanisms of polysaccharides differ. After extraction, the structure and biological activity of the obtained polysaccharides also differ. To date, approximately 58 kinds of polysaccharides have been isolated and purified from the Lycium genus, including water-soluble polysaccharides; homogeneous polysaccharides; pectin polysaccharides; acidic heteropolysaccharides; and arabinogalactans, which are composed of arabinose, glucosamine, galactose, glucose, xylose, mannose, fructose, ribose, galacturonic acid, and glucuronic acid. Pharmacological studies have shown that LBPs exhibit a variety of important biological activities, such as protection of nerves; promotion of reproduction; and anti-inflammatory, hepatoprotective, hypoglycemic, and eyesight-improving activities. The aim this paper is to summarize previous and current references to the isolation process, structural characteristics, and biological activities of the genus Lycium L. polysaccharide. This review will provide a useful reference for further research and application of the genus Lycium L. polysaccharide in the field of functional food and medicine. Full article

► Show Figures

Graphical abstract

9 pages, 1607 KiB

Open AccessArticle

Optimized Isolation of Safranal from Saffron by Solid-Phase Microextraction (SPME) and Rotatable Central Composite Design-Response Surface Methodology (RCCD-RSM)

by Panagiota-Kyriaki Revelou, Spyridoula Mouzoula, Marinos Xagoraris, Haralambos Evangelaras, George K. Papadopoulos, Christos S. Pappas and Petros A. Tarantilis

Separations 2022, 9(2), 48; https://doi.org/10.3390/separations9020048 - 10 Feb 2022

Viewed by 3576

Abstract

Safranal is the main aroma component of saffron stigmas. It is also a great antioxidant with known pharmacological properties and is a potent indicator for the grading and authentication of saffron. In this study, the optimum extraction conditions of safranal from saffron stigmas were investigated using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) and response surface methodology (RSM). A rotatable-central composite design was applied, and a linear regression model has been used for the model building. The optimized factors were as follows: sample weight (15 mg), water volume (4 mL), exposure time in the headspace (20 min), and extraction temperature (45 °C). All factors were found significant; however, extraction temperature and exposure time were the most important for the isolation of safranal. The obtained model was successfully validated with a test set of saffron samples analyzed under the optimum extraction conditions. The optimized SPME extraction conditions of safranal found in this study contribute to the efforts towards the detection of saffron authentication and adulteration. Full article

► Show Figures

Figure 1

2021

Jump to: 2024, 2023, 2022

9 pages, 2347 KiB

Open AccessArticle

Improvement of Cucurbitacin B Content in Cucumis melo Pedicel Extracts by Biotransformation Using Recombinant β-Glucosidase

by Jianfeng Mei, Xia Wu, Sujing Zheng, Xiang Chen, Zhuliang Huang and Yichun Wu

Separations 2021, 8(9), 138; https://doi.org/10.3390/separations8090138 - 1 Sep 2021

Cited by 1 | Viewed by 2340

Abstract

For the efficient biotransformation of cucurbitacin B 2-o-β-d-glucoside (CuBg) to cucurbitacin B (CuB) in Cucumis melo pedicel extracts, the β-glucosidase gene bglS—consisting of 1344 bp (447 amino acids) from Streptomyces sp. RW-2—was cloned and expressed in Escherichia coli BL21(DE3). The activity of recombinant β-glucosidase with p-nitrophenyl-β-d-glucoside (pNPG) as a substrate was 3.48 U/mL in a culture. Using the recombinant β-glucosidase for the biotransformation of C. melo pedicel extracts, CuBg was converted into CuB with a conversion rate of 87.6% when the concentration of CuBg was 0.973 g/L in a reaction mixtures. The concentration of CuB in C. melo pedicel extracts was improved from 13.6 to 20.2 g/L after biotransformation. The present study provides high-efficiency technology for the production of CuB from its glycoside by biotransformation. Full article

► Show Figures

Graphical abstract

17 pages, 3218 KiB

Open AccessArticle

Optimum Parameters for Extracting Three Kinds of Carotenoids from Pepper Leaves by Response Surface Methodology

by Nenghui Li, Jing Li, Dongxia Ding, Jianming Xie, Jing Zhang, Wangxiong Li, Yufeng Ma, Feng Gao, Tianhang Niu, Cheng Wang and Emily Patience Bakpa

Separations 2021, 8(9), 134; https://doi.org/10.3390/separations8090134 - 26 Aug 2021

Cited by 6 | Viewed by 2652

Abstract

To determine the optimum parameters for extracting three carotenoids including zeaxanthin, lutein epoxide, and violaxanthin from pepper leaves by response surface methodology (RSM), a solvent of acetone and ethyl acetate (1:2) was used to extract carotenoids with four independent factors: ultrasound time (20–60 min); ratio of sample to solvent (1:12–1:4); saponification time (10–50 min); and concentration of saponification solution (KOH–methanol) (10–30%). A second-order polynomial model produced a satisfactory fitting of the experimental data with regard to zeaxanthin (R² = 75.95%, p < 0.0197), lutein epoxide (R² = 90.24%, p < 0.0001), and violaxanthin (R² = 73.84%, p < 0.0809) content. The optimum joint extraction conditions of zeaxanthin, lutein epoxide, and violaxanthin were 40 min, 1:8, 32 min, and 20%, respectively. The optimal predicted contents for zeaxanthin (0.823022 µg/g DW), lutein epoxide (4.03684 µg/g dry; DW—dry weight), and violaxanthin (16.1972 µg/g DW) in extraction had little difference with the actual experimental values obtained under the optimum extraction conditions for each response: zeaxanthin (0.8118 µg/g DW), lutein epoxide (3.9497 µg/g DW), and violaxanthin (16.1590 µg/g DW), which provides a theoretical basis and method for cultivating new varieties at low temperatures and weak light resistance. Full article

► Show Figures

Graphical abstract

Journal Menu

Journal Browser

Recent Trends in the Separation of Natural Products and Pharmaceuticals

Share This Topical Collection

Editors

Topical Collection Information

Keywords

Published Papers (9 papers)

2024

Jump to: 2023, 2022, 2021

2023

Jump to: 2024, 2022, 2021

2022

Jump to: 2024, 2023, 2021

2021

Jump to: 2024, 2023, 2022

Further Information

Guidelines

MDPI Initiatives

Follow MDPI