Publications by authors named "Robert Verpoorte"

180 Publications

Measuring the health effects of food by metabolomics.

Crit Rev Food Sci Nutr 2021 Mar 22:1-15. Epub 2021 Mar 22.

Natural Products Laboratory, Institute of Biology, Leiden University, Leiden, RA, The Netherlands.

Metabolomics of human biological fluids or tissues is used to discover markers for diseases by comparing the metabolome of the patients against healthy individuals. Ultimately, these markers can be used in drug discovery to determine how medications normalize (at least in part) the human metabolome at specific disease stages to homeostatic. Likewise, the health effects of food can be studied. Even metabolomics of the food can be combined with metabolomics of the treated patients to correlate compounds from food with measurable health effects from clinical studies. Various chemometric analyses of these metabolomics data are used to identify markers for diseases and to obtain evidence for health effects. This review discusses recent researches (published from 2013 to 2021) on whether specific dietary intervention to humans suffering from metabolic disorders may improve their pathological status. The scope is limited to those associated with major lifestyle diseases such as diabetes, obesity, and cardiovascular diseases, for which food is thought may have detrimental as well as beneficial effects on human health. It includes metabolites characterization of different biological samples such as the human serum/plasma, urine, saliva, feces, or ileal fluid. Whether the study results supported the claimed health benefits and whether the research was conducted with appropriate study design, was criticized.
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http://dx.doi.org/10.1080/10408398.2021.1901256DOI Listing
March 2021

Fast dereplication of xanthine oxidase-inhibiting compounds in alfalfa using comparative metabolomics.

Food Res Int 2021 Mar 26;141:110170. Epub 2021 Jan 26.

School of Pharmacy, Taipei Medical University, Taipei City, Taiwan; School of Food Safety, Taipei Medical University, Taipei City, Taiwan. Electronic address:

Xanthine oxidase (XO) inhibition is a major strategy for preventing hyperuricemia and associated comorbidities, such as gout. Alfalfa extract has been demonstrated to possess XO-inhibiting activity; however, the elaborate conventional fraction-by-fraction analyses hindered the identification of the active components. In this study, we established a streamlined approach to rapidly screen, identify, and characterize XO-interacting compounds in alfalfa, by incorporating protein-subtraction, mass profiling, and molecular docking analysis. Crude extract was incubated with or without XO protein before UPLC-ESI-Q-TOF-MS/MS composition profiling. By dereplicating the component profile of XO-subtracted extract from that of untreated extract, the targets were rapidly narrowed down to twelve XO-interacting compounds, regarded as potential xanthine oxidase inhibitors (XOIs). Molecular docking analysis revealed that nine of these compounds, namely salicylic acid, tricin 7-O-glucuronopyranoside, chrysoeriol-7-glucoside, ferulic acid, apigenin 7-O-β-glucuronopyranoside, apigenin, tricin, chrysoeriol, and liquiritigenin, exhibited high affinity with XO, and depicted the possible mechanisms of inhibition. In vitro bioassay further verified the XO inhibitory activities of selected compounds, among which apigenin, chrysoeriol and liquiritigenin were more potent XO inhibitors (XOIs), with IC of 0.25, 0.5 and 1 µM, respectively, compared to allopurinol (IC = 1.41 µM), the well-known XO-inhibiting drug. Together, the results demonstrated that alfalfa is a promising natural source for potent XOIs which might be applied for nutraceuticals development and that the approach used is applicable for efficient screening, identification, and mechanistic analyses of enzyme-inhibiting compounds from plant-based resources.
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http://dx.doi.org/10.1016/j.foodres.2021.110170DOI Listing
March 2021

The intractum from the Eleutherococcus senticosus fruits affects the innate immunity in human leukocytes: From the ethnomedicinal use to contemporary evidence-based research.

J Ethnopharmacol 2021 Mar 1;268:113636. Epub 2020 Dec 1.

Department of Pharmaceutical Botany and Pharmacognosy, Ludwik Rydygier Collegium Medicum, Nicolaus Copernicus University, 9 Marie Curie-Skłodowska Street, 85-094, Bydgoszcz, Poland. Electronic address:

Ethnopharmacological Relevance: In the ethnomedicine of Russia, the Eleutherococcus senticosus (Rupr. et Maxim.) Maxim. fruits and roots are used to treat immune-related diseases. Because of the overexploitation of the roots, the species is considered to be endangered and is put on the Red List in some countries (e.g. the Republic of Korea). Therefore, the aerial parts of E. senticosus might be explored as a new sustainable source of compounds with an adaptogenic activity.

Aim Of The Study: This study is aimed to evaluate the adaptogenic activity of the Eleutherococcus senticosus fruits intractum to support the use of the fruits in folk medicine of Russia.

Materials And Methods: The effect on IL-2 and IL-10 release by peripheral blood leukocytes (PBLs) was measured by the ELISA, the CPE on the A549 and PBLs were determined with trypan blue and the MTT. The innate immunity assay was done in the VSV-PBLs model. Metabolic profiling was done using HPLC-DAD and HPLC-RID.

Results: We report for the first time that the intractum (300 μg/mL) and eleutheroside E (100 μg/mL) and B (100 μg/mL) do not act as a virucidal agent (VSV). The intractum and eleutherosides E and B caused the increase of the PBLs proliferation up to 24.61 and 100%, resp. The decreased viral replication in the VSV-PBLs-Int model might be associated with an increased secretion of IL-10 (328 pg/mL). Eleutheroside E and B did not affect the innate immunity. No eleutherosides were determined in the intractum, the ethyl acetate layer contained caffeic and protocatechuic acids. A large amount of myo-inositol and D-mannitol was found (267.5 and 492.5 mg/g DE).

Conclusions: Our observations justify the traditional use of the fruits in Russia in immune-related diseases. The results mean that there are other compounds than eleutherosides responsible for the adaptogenic effect, probably myo-inositol and caffeic acid, for which an immunostimulatory activity has already been confirmed.
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http://dx.doi.org/10.1016/j.jep.2020.113636DOI Listing
March 2021

Natural Deep Eutectic Solvent Extraction of Flavonoids of as a Replacement for Conventional Organic Solvents.

Molecules 2020 Jan 31;25(3). Epub 2020 Jan 31.

Natural Products Laboratory, Institute of Biology, Leiden University, Sylviusweg 72, 2333 BE Leiden, The Netherlands.

Natural deep eutectic solvents (NADES) are a type of ionic liquid (IL) or deep eutectic solvent (DES), the ingredients of which are exclusively natural products (non-toxic and environmentally friendly). Here, we explore the potential of NADES as an alternative to conventional organic solvents (e.g., aqueous methanol or ethanol) for the extraction of flavonoids from stem bark to investigate their extractability depending on structural variation. Four NADES, each containing citric acid in combination with β-alanine, glucose, xylitol, or proline (at a molar ratio of 1:1), and a variable amount of water, were used to extract the flavonoid aglycones: baicalein (), scutellarein (), wogonin (), and oroxylin A (), and their glycosides, baicalin (), scutellarin (), wogonoside () and oroxyloside () from the powdered bark of . The chemical profile and yield of the extracts were determined using HPTLC and HPLC. The extractability of individual flavonoids was found to be influenced by the concentration of water (20-60%, w/w) in the NADES. Among the tested flavonoids, the extraction yield of baicalein (), scutellarein (), wogonin (), oroxylin A () with NADES was 2 to 6 times that of aqueous methanol. However, the amount of their corresponding glycosides (baicalin (), wogonoside () and oroxyloside ()) extracted with NADES was only 1.5-1.8 times higher than with aqueous methanol. Interestingly, the more hydrophilic glycosides were less extracted than their corresponding aglycones despite the high hydrophilicity of the NADES. These results prove that NADES may be used for extraction of compounds with a wide range of hydrophilicity.
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http://dx.doi.org/10.3390/molecules25030617DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7038101PMC
January 2020

Natural deep eutectic characteristics of honey improve the bioactivity and safety of traditional medicines.

J Ethnopharmacol 2020 Mar 16;250:112460. Epub 2019 Dec 16.

Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Nanxiaojie 16, Dongzhimennei Ave, 100700, Beijing, China.

Ethnopharmacological Relevance: Honey, an important additive with natural deep eutectic solvent (NADES) characteristics, has been used in traditional medicine for thousands of years.

Aim Of The Study: We investigated the quality-improving effects of honey on Astragali Radix (Mikvetch Root) (RA) as an example.

Materials And Methods: Decoctions of raw RA, fried RA, honey-fried RA, and a man-made- honey-fried RA were prepared and compared in cell-based bioactivity tests, chemical composition tests, as well as a bioavailability test with calycosin-7-O-β-D-glucoside.

Results: The addition of honey increased the concentrations of active compounds and their oral bioavailability, provided protection against acetylation, and consequently increased their bioactivity. These changes were also observed when a pure NADES-mimicking honey was used.

Conclusion: Our findings provide a potential explanation as to why honey has long been used as traditional medicine additives and rationalize the application of honey and honey-like substance in producing pharmaceuticals.
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http://dx.doi.org/10.1016/j.jep.2019.112460DOI Listing
March 2020

The perspectives of natural deep eutectic solvents in agri-food sector.

Crit Rev Food Sci Nutr 2020 13;60(15):2564-2592. Epub 2019 Aug 13.

Natural Products Laboratory, Institute of Biology, Leiden University, Leiden, The Netherlands.

The principles of 'green chemistry' are gaining importance in agri-food sector due to the need to reduce pollution from toxic chemicals, make industrial processes safer and more sustainable, and to offer 'clean-labeled products' required by the consumers. The application of natural deep eutectic solvents (NADES) - natural product-based green liquids is considered the promising alternative to conventional organic solvents. This review is intended to summarize and discuss recent advances related to physicochemical properties of NADES, their applications, compatibility with analytic techniques and toxicological profile, pointing out the challenges and necessary improvements for their wider utilization in agri-food sector. NADES allow extraction of wide range of food compounds and they are proven to be convenient for food-related applications. However, their potential for industrial scale-up utilization is not completely investigated. Examined NADES are readily biodegradable, but only preliminary studies on NADES toxicity which include limited number of NADES molecules are available. Apart from fundamental research dealing with NADES formation and the nature of the interactions and structure underpinning the liquid phase formation, the question of purity of NADES obtained by different synthetic methodologies need to be addressed in the future. Data on physicochemical properties of synthetized NADES are still needed as they are relevant for industrial applications.
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http://dx.doi.org/10.1080/10408398.2019.1650717DOI Listing
September 2020

Metabolomics reveals novel insight on dormancy of aquatic invertebrate encysted embryos.

Sci Rep 2019 06 20;9(1):8878. Epub 2019 Jun 20.

Faculty of Biology, Technion, Haifa, Israel.

Numerous aquatic invertebrates survive harsh environments by displaying dormancy as encysted embryos. This study aimed at determining whether metabolomics could provide molecular insight to explain the "dormancy syndrome" by highlighting functional pathways and metabolites, hence offering a novel comprehensive molecular view of dormancy. We compared the metabolome of morphologically distinct dormant encysted embryos (resting eggs) and non-dormant embryos (amictic eggs) of a rotifer (Brachionus plicatilis). Metabolome profiling revealed ~5,000 features, 1,079 of which were annotated. Most of the features were represented at significantly higher levels in non-dormant than dormant embryos. A large number of features was assigned to putative functional pathways indicating novel differences between dormant and non-dormant states. These include features associated with glycolysis, the TCA and urea cycles, amino acid, purine and pyrimidine metabolism. Interestingly, ATP, nucleobases, cyclic nucleotides, thymidine and uracil, were not detected in dormant resting eggs, suggesting an impairment of response to environmental and internal cues, cessation of DNA synthesis, transcription and plausibly translation in the dormant embryos. The levels of trehalose or its analogues, with a role in survival under desiccation conditions, were higher in resting eggs. In conclusion, the current study highlights metabolomics as a major analytical tool to functionally compare dormancy across species.
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http://dx.doi.org/10.1038/s41598-019-45061-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6586685PMC
June 2019

Effect of Benzothiadiazole on the Metabolome of Tomato Plants Infected by Citrus Exocortis Viroid.

Viruses 2019 05 14;11(5). Epub 2019 May 14.

Instituto de Biología Molecular y Celular de Plantas, Universitat Politècnica de València (UPV)-Consejo Superior de Investigaciones Científicas (CSIC), Ciudad Politécnica de la Innovación (CPI), Ingeniero Fausto Elio s/n, 46022 Valencia, Spain.

Benzothiadiazole (BTH) is a functional analogue of the phytohormone salycilic acid (SA) involved in the plant immune response. NahG tomato plants are unable to accumulate SA, which makes them hypersusceptible to several pathogens. Treatments with BTH increase the resistance to bacterial, fungal, viroid, or viral infections. In this study, metabolic alterations in BTH-treated Money Maker and NahG tomato plants infected by citrus exocortis viroid (CEVd) were investigated by nuclear magnetic resonance spectroscopy. Using multivariate data analysis, we have identified defence metabolites induced after viroid infection and BTH-treatment. Glycosylated phenolic compounds include gentisic and ferulic acid accumulated in CEVd-infected tomato plants, as well as phenylalanine, tyrosine, aspartate, glutamate, and asparagine. Besides, an increase of γ-aminobutyric acid (GABA), glutamine, adenosine, and trigonelline, contributed to a clear discrimination between the metabolome of BTH-treated tomato leaves and their corresponding controls. Among them, GABA was the only metabolite significantly accumulated in both genotypes after the chemical treatment. In view of these results, the addition of GABA was performed on tomato plants infected by CEVd, and a reversion of the NahG hypersusceptibility to CEVd was observed, indicating that GABA could regulate the resistance to CEVd induced by BTH.
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http://dx.doi.org/10.3390/v11050437DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6563216PMC
May 2019

Quality marker identification based on standard decoction of differently processed materials of Ephedrae Herba.

J Ethnopharmacol 2019 Jun 18;237:47-54. Epub 2019 Mar 18.

Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing, China. Electronic address:

Ethnopharmacological Relevance: The quality control of Traditional Chinese medicine (TCM) is a scientific problem and an industrial issue, which hampers the development of evidence based TCM. The concept of quality markers (Q-markers) is proposed and has been applied to the quality evaluation of TCM based on its clinical efficacy. However, more specific methods are needed to put this idea into practice. The standard decoction is a representative of decoction used in clinical practice and it can be used for the discovery of Q-markers related to the clinical efficacy of TCM.

Aim Of The Study: In this study, a systemic strategy was established to discover Q-markers related to the clinical efficacy of TCM Ephedrae Herba (EH), dried stem of Ephedra sinica Stapf. The different processed materials of EH have different clinical applications, though originating from the same medicinal herb.

Materials And Methods: The standard decoction of each of the processed materials was prepared and a HNMR metabolomics approach and total polysaccharide analysis were used to identify potential Q-markers related to the different clinical applications of EH. Correlation analysis was made of the measured biological activity and the holistic chemical profile.

Results: The results showed that total polysaccharides and alkaloids were Q-markers for EH preparations.

Conclusion: This study demonstrates that the standard decoction is a reasonable research objective to explore chemical markers that correlate with the clinical efficacy of TCM.
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http://dx.doi.org/10.1016/j.jep.2019.03.025DOI Listing
June 2019

Natural Deep Eutectic Solvents as Multifunctional Media for the Valorization of Agricultural Wastes.

ChemSusChem 2019 Apr 6;12(7):1310-1315. Epub 2019 Mar 6.

School of Food Science and Engineering, State Key Laboratory of Pulp and Paper Engineering, Overseas Expertise Introduction Center for Discipline Innovation of Food Nutrition and Human Health (111 Center), South China University of Technology, Guangzhou, 510640, P.R. China.

The use of natural deep eutectic solvents (NADES) as multifunctional solvents for limonene bioprocessing was reported. NADES were used for the extraction of limonene from orange peel wastes, as solvent for the chemoenzymatic epoxidation of limonene, and as sacrificial electron donor for the in situ generation of H O to promote the epoxidation reaction. The proof-of-concept for this multifunctional use was provided, and the scope and current limitations of the concept were outlined.
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http://dx.doi.org/10.1002/cssc.201900043DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6563711PMC
April 2019

Correction: The value of universally available raw NMR data for transparency, reproducibility, and integrity in natural product research.

Nat Prod Rep 2019 01 23;36(1):248-249. Epub 2018 Nov 23.

Center for Natural Product Technologies (CENAPT), Program for Collaborative Research in the Pharmaceutical Sciences (PCRPS), Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, 833 S. Wood St., Chicago, IL 60612, USA.

Correction for 'The value of universally available raw NMR data for transparency, reproducibility, and integrity in natural product research' by James B. McAlpine et al., Nat. Prod. Rep., 2018, DOI: .
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http://dx.doi.org/10.1039/c8np90041hDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6474672PMC
January 2019

The value of universally available raw NMR data for transparency, reproducibility, and integrity in natural product research.

Nat Prod Rep 2019 01 13;36(1):35-107. Epub 2018 Jul 13.

Center for Natural Product Technologies (CENAPT), Program for Collaborative Research in the Pharmaceutical Sciences (PCRPS), Department of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, University of Illinois at Chicago, 833 S. Wood St., Chicago, IL 60612, USA.

Covering: up to 2018With contributions from the global natural product (NP) research community, and continuing the Raw Data Initiative, this review collects a comprehensive demonstration of the immense scientific value of disseminating raw nuclear magnetic resonance (NMR) data, independently of, and in parallel with, classical publishing outlets. A comprehensive compilation of historic to present-day cases as well as contemporary and future applications show that addressing the urgent need for a repository of publicly accessible raw NMR data has the potential to transform natural products (NPs) and associated fields of chemical and biomedical research. The call for advancing open sharing mechanisms for raw data is intended to enhance the transparency of experimental protocols, augment the reproducibility of reported outcomes, including biological studies, become a regular component of responsible research, and thereby enrich the integrity of NP research and related fields.
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http://dx.doi.org/10.1039/c7np00064bDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6350634PMC
January 2019

Analysis of Terpenoid Indole Alkaloids, Carotenoids, Phytosterols, and NMR-Based Metabolomics for Catharanthus roseus Cell Suspension Cultures.

Methods Mol Biol 2018 ;1815:437-455

Natural Products Laboratory, Institute of Biology, Leiden University, Leiden, The Netherlands.

The plant Catharanthus roseus is a rich source of terpenoid indole alkaloids (TIA). Some of the TIA are important as antihypertensive (ajmalicine) and anticancer (vinblastine and vincristine) drugs. However, production of the latter is very low in the plant. Therefore, in vitro plant cell cultures have been considered as a potential supply of these chemicals or their precursors. Some monomeric alkaloids can be produced by plant cell cultures, but not on a level feasible for commercialization, despite extensive studies on this plant that deepened the understanding of the TIA biosynthesis and its regulation. In order to analyze the metabolites in C. roseus cell cultures, this chapter presents the method of TIA, carotenoids, and phytosterols analyses. Furthermore, an NMR-based metabolomics approach to study C. roseus cell culture is described.
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http://dx.doi.org/10.1007/978-1-4939-8594-4_31DOI Listing
March 2019

Effects of processing adjuvants on traditional Chinese herbs.

J Food Drug Anal 2018 04 19;26(2S):S96-S114. Epub 2018 Mar 19.

Graduate Institute of Health Industry Technology, Research Center for Food and Cosmetic Safety, and Research Center for Chinese Herbal Medicine, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan; Department of Gastroenterology and Hepatology, Chang Gung Memorial Hospital, Taoyuan, Taiwan. Electronic address:

Processing of Chinese medicines is a pharmaceutical technique that transforms medicinal raw materials into decoction pieces for use in different therapies. Various adjuvants, such as vinegar, wine, honey, and brine, are used in the processing to enhance the efficacy and reduce the toxicity of crude drugs. Proper processing is essential to ensure the quality and safety of traditional Chinese medicines (TCMs). Therefore, sound knowledge of processing principles is crucial to the standardized use of these processing adjuvants and to facilitate the production and clinical use of decoction pieces. Many scientific reports have indicated the synergistic effects of processing mechanisms on the chemistry, pharmacology, and pharmacokinetics of the active ingredients in TCMs. Under certain conditions, adjuvants change the content of active or toxic components in drugs by chemical or physical transformation, increase or decrease drug dissolution, exert their own pharmacological effects, or alter drug pharmacokinetics. This review summarizes various processing methods adopted in the last two decades, and highlights current approaches to identify the effects of processing parameters on TCMs.
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http://dx.doi.org/10.1016/j.jfda.2018.02.004DOI Listing
April 2018

Metabolic alteration of cell suspension cultures overexpressing in the plastids or cytosol.

Plant Cell Tissue Organ Cult 2018 24;134(1):41-53. Epub 2018 Feb 24.

1Institute of Biology, Leiden University, 2300 RA Leiden, The Netherlands.

Previous studies showed that geraniol could be an upstream limiting factor in the monoterpenoid pathway towards the production of terpenoid indole alkaloid (TIA) in cells and hairy root cultures. This shortage in precursor availability could be due to (1) limited expression of the plastidial resulted in a low activity of the enzyme to catalyze the conversion of geranyl diphosphate to geraniol; or (2) the limitation of geraniol transport from plastids to cytosol. Therefore, in this study, 's () gene was overexpressed in either plastids or cytosol of a non-TIA producing cell line. The expression of in the plastids or cytosol was confirmed and the constitutive transformation lines were successfully established. A targeted metabolite analysis using HPLC shows that the transformed cell lines did not produce TIA or iridoid precursors unless elicited with jasmonic acid, as their parent cell line. This indicates a requirement for expression of additional, inducible pathway genes to reach production of TIA in this cell line. Interestingly, further analysis using NMR-based metabolomics reveals that the overexpression of impacts primary metabolism differently if expressed in the plastids or cytosol. The levels of valine, leucine, and some metabolites derived from the shikimate pathway, i.e. phenylalanine and tyrosine were significantly higher in the plastidial- but lower in the cytosolic- overexpressing cell lines. This result shows that overexpression of in the plastids or cytosol caused alteration of primary metabolism that associated to the plant cell growth and development. A comprehensive omics analysis is necessary to reveal the full effect of metabolic engineering.
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http://dx.doi.org/10.1007/s11240-018-1398-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6445406PMC
February 2018

Broad range chemical profiling of natural deep eutectic solvent extracts using a high performance thin layer chromatography-based method.

J Chromatogr A 2018 Jan 6;1532:198-207. Epub 2017 Dec 6.

Natural Products Laboratory, Institute of Biology, Leiden University, 2333 BE Leiden, The Netherlands; College of Pharmacy, Kyung Hee University, 02447 Seoul, Republic of Korea. Electronic address:

Natural deep eutectic solvents (NADES) made mainly with abundant primary metabolites are being increasingly applied in green chemistry. The advantages of NADES as green solvents have led to their use in novel green products for the food, cosmetics and pharma markets. However, one of the main difficulties encountered in the development of novel products and their quality control arises from their low vapour pressure and high viscosity. These features create the need for the development of new analytical methods suited to this type of sample. In this study, such a method was developed and applied to analyse the efficiency of a diverse set of NADES for the extraction of compounds of interest from two model plants, Ginkgo biloba and Panax ginseng. The method uses high-performance thin-layer chromatography (HPTLC) coupled with multivariate data analysis (MVDA). It was successfully applied to the comparative quali- and quantitative analysis of very chemically diverse metabolites (e.g., phenolics, terpenoids, phenolic acids and saponins) that are present in the extracts obtained from the plants using six different NADES. The composition of each NADES was a combination of two or three compounds mixed in defined molar ratios; malic acid-choline chloride (1:1), malic acid-glucose (1:1), choline chloride-glucose (5:2), malic acid-proline (1:1), glucose-fructose-sucrose (1:1:1) and glycerol-proline-sucrose (9:4:1). Of these mixtures, malic acid-choline chloride (1:1) and glycerol-proline-sucrose (1:1:1) for G. biloba leaves, and malic acid-choline chloride (1:1) and malic acid-glucose (1:1) for P. ginseng leaves and stems showed the highest yields of the target compounds. Interestingly, none of the NADES extracted ginkgolic acids as much as the conventional organic solvents. As these compounds are considered to be toxic, the fact that these NADES produce virtually ginkgolic acid-free extracts is extremely useful. The effect of adding different volumes of water to the most efficient NADES was also evaluated and the results revealed that there is a great influence exerted by the water content, with maximum yields of ginkgolides, phenolics and ginsenosides being obtained with approximately 20% water (w/w).
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http://dx.doi.org/10.1016/j.chroma.2017.12.009DOI Listing
January 2018

LC-ESI-MS/MS profiling of phenolics from spp. inflorescences, structure-activity relationship as antioxidants, inhibitors of hyaluronidase and acetylcholinesterase.

Saudi Pharm J 2017 Jul 12;25(5):734-743. Epub 2016 Nov 12.

Department of Pharmaceutical Botany, Medical University of Lublin, 1 Chodźki Street, 20-093 Lublin, Poland.

Nature is a source of many plant-based molecules used as pro- or drugs. species are native to Asia and the North Russia, and are traditionally used to treat various diseases. In turn, neither secondary metabolites of the species cultivated in the West Europe nor the bioactivity is known. No differences in the phenols and flavonoids content in the inflorescences were found. The richest in polyphenols was (5.18 mg/g), while in flavonoids it was (1.80 mg/g). Using LC-ESI-MS/MS, protocatechuic and -caffeic acids have been identified as the most abundant compounds in , , (833.4; 855.6; 614.7 and 280.8; 156.0; 167.6 μg/g DE). It was observed that all species were able to chelate Fe with the EC value of 0.2, 0.6, 0.3 mg/mL for , , , respectively. exhibited the strongest antiperoxidation and anti-DPPH activity (EC 3.2 and 0.48 mg/mL). The weak inhibitory potential has been observed in case of AChE inhibition at the level of 16.17 and 12.2% for , . We report for the first time that the extracts inhibited Hyal activity in the range from 16.4 to 60.7%. To our best knowledge, no information was available on this activity of the inflorescences and this provides a background to study inflorescences in more detail. Considering the SAR, an antioxidant activity may be correlated with a high amount of protocatechuic and -caffeic acids and their chemical structure.
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http://dx.doi.org/10.1016/j.jsps.2016.11.002DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5506723PMC
July 2017

Major achievements of evidence-based traditional Chinese medicine in treating major diseases.

Biochem Pharmacol 2017 09 19;139:94-104. Epub 2017 Jun 19.

Institute of Chinese Materia Medica, China Academy of Chinese Medical Sciences, Beijing. Electronic address:

A long history of use and extensive documentation of the clinical practices of traditional Chinese medicine resulted in a considerable number of classical preparations, which are still widely used. This heritage of our ancestors provides a unique resource for drug discovery. Already, a number of important drugs have been developed from traditional medicines, which in fact form the core of Western pharmacotherapy. Therefore, this article discusses the differences in drug development between traditional medicine and Western medicine. Moreover, the article uses the discovery of artemisinin as an example that illustrates the "bedside-bench-bedside" approach to drug discovery to explain that the middle way for drug development is to take advantage of the best features of these two distinct systems and compensate for certain weaknesses in each. This article also summarizes evidence-based traditional medicines and discusses quality control and quality assessment, the crucial steps in botanical drug development. Herbgenomics may provide effective tools to clarify the molecular mechanism of traditional medicines in the botanical drug development. The totality-of-the-evidence approach used by the U.S. Food and Drug Administration for botanical products provides the directions on how to perform quality control from the field throughout the entire production process.
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http://dx.doi.org/10.1016/j.bcp.2017.06.123DOI Listing
September 2017

Looking to nature for a new concept in antimicrobial treatments: isoflavonoids from Cytisus striatus as antibiotic adjuvants against MRSA.

Sci Rep 2017 06 19;7(1):3777. Epub 2017 Jun 19.

Natural Products Laboratory, Institute of Biology, Leiden University, Leiden, The Netherlands.

The spread of multidrug-resistant Staphylococcus aureus strains, including methicillin-resistant S. aureus (MRSA), has shortened the useful life of anti-staphylococcal drugs enormously. Two approaches can be followed to address this problem: screening various sources for new leads for antibiotics or finding ways to disable the resistance mechanisms to existing antibiotics. Plants are resistant to most microorganisms, but despite extensive efforts to identify metabolites that are responsible for this resistance, no substantial progress has been made. Plants possibly use multiple strategies to deal with microorganisms that evolved over time. For this reason, we searched for plants that could potentiate the effects of known antibiotics. From 29 plant species tested, Cytisus striatus clearly showed such an activity and an NMR-based metabolomics study allowed the identification of compounds from the plant extracts that could act as antibiotic adjuvants. Isoflavonoids were found to potentiate the effect of ciprofloxacin and erythromycin against MRSA strains. For the structure-activity relationship (SAR), 22 isoflavonoids were assessed as antibiotic adjuvants. This study reveals a clear synergy between isoflavonoids and the tested antibiotics, showing their great potential for applications in the clinical therapy of infections with antibiotic-resistant microorganisms such as MRSA.
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http://dx.doi.org/10.1038/s41598-017-03716-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5476642PMC
June 2017

Phytoconstituents and Nutritional Properties of the Fruits of and : A Study of Non-European Species Cultivated in Poland.

Oxid Med Cell Longev 2017 15;2017:8374295. Epub 2017 Jan 15.

Chair and Department of Pharmaceutical Botany, Medical University of Lublin, 1 Chodźki Street, 20-093 Lublin, Poland.

fruits have been consumed in Russia and Asia throughout the centuries. Currently, there is an increasing interest in these products by the community of Western Europe. Many people suffer from micronutrient deficiencies, known as malnutrition, which consequently influences body condition. The aim of this study was to investigate pharmaconutrition, proximate, mineral, and fatty acid composition, total phenolics content, and total flavonoids content of and fruits cultivated in Poland. and contain a high amount of protein and fibres (16.70% and 12.28%; 61.41% and 45.63%, resp.). The fruits were generally high in K (21 g/kg) and low in sodium (0.001 g/kg). In terms of fatty acid composition, both species had a high amount of monounsaturated fatty acids (54.84-57.95%) and polyunsaturated fatty acids (36.22-37.0%). Using LC-ESI-MS/MS, protocatechuic acid has been identified as the most abundant compound, ranging from 260 to 810 g/100 g DE. Among flavonoids, hyperoside was found to be in the highest amount (120-780 g/100 g DE). Considering a rich chemical composition of the fruits, a better understanding of their health benefits is important in order to increase their utility and to enrich dietary sources of health promoting compounds. Because of a high amount of protein and a low calorific value, the fruits should be considered food for vegans or vegetarians.
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http://dx.doi.org/10.1155/2017/8374295DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5274665PMC
March 2017

Traditional Mediterranean and European herbal medicines.

J Ethnopharmacol 2017 Mar 5;199:161-167. Epub 2017 Feb 5.

Natural Products Laboratory, IBL, Leiden University, 2300 Leiden, The Netherlands.

Ethnopharmacological Relevance: Written history allows tracing back Mediterranean and European medical traditions to Greek antiquity. The epidemiological shift triggered by the rise of modern medicine and industrialization is reflected in contemporary reliance and preferences for certain herbal medicines.

Materials And Methods: We sketch the development and transmission of written herbal medicine through Mediterranean and European history and point out the opportunity to connect with modern traditions.

Results: An ethnopharmacological database linking past and modern medical traditions could serve as a tool for crosschecking contemporary ethnopharmacological field-data as well as a repository for data mining. Considering that the diachronic picture emerging from such a database has an epidemiological base this could lead to new hypotheses related to evolutionary medicine.

Conclusion: The advent of systems pharmacology and network pharmacology opens new perspectives for studying past and current herbal medicine. Since a large part of modern drugs has its roots in ancient traditions one may expect new leads for drug development from novel systemic studies, as well as evidence for the activity of certain herbal preparations.
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http://dx.doi.org/10.1016/j.jep.2017.01.052DOI Listing
March 2017

Phytochemical Content and Pharma-Nutrition Study on Fruits Intractum.

Oxid Med Cell Longev 2016 24;2016:9270691. Epub 2016 Oct 24.

Department of Biology and Genetics, Medical University of Lublin, 4a Chodźki Street, 20-093 Lublin, Poland.

In the past two decades public interest in herbal products has increased significantly in Europe, especially in the plant-based products from non-European traditions. has been used for the treatment of inflammatory diseases, anemia, and rheumatoid arthritis. The fruits intractum was examined for the content of phenolic acids (LC-ESI-MS/MS), minerals (AAS), TPC, and TFC (spectrophotometric assay). The antioxidant activity was determined using free radical scavenging assay and TLC-DB-DPPH dot-blot test. An anti-Hyal activity was evaluated by the spectrophotometric assay method. Cytotoxicity towards HL-60, HL-60/MX1, HL-60/MX2, CEM/C1, and CCRF/CEM leukemic cell lines was done using trypan blue test. Among eight phenolic acids, -caffeic acid was found in the largest amount (41.2 mg/g DE). The intractum presented a high amount of macroelements (Ca, Mg, K; 1750, 1300, and 21000 mg/kg) and microelements (Fe, Mn; 32.7, 54.3 mg/kg), respectively. The content of TPC and TFC was 130 and 92 mg/g DE, respectively. The intractum showed anti-Hyal activity (2.16-60%) and an antioxidant capacity (EC; 52 g/mL). The intractum most strongly inhibited the growth of HL-60, HL-60/MX1, and CCRF/CEM. A better understanding of the intractum health benefits is important in order to increase its utility and enrich dietary sources of health promoting compounds.
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http://dx.doi.org/10.1155/2016/9270691DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5098108PMC
March 2017

Incorporation of an invasive plant into a native insect herbivore food web.

PeerJ 2016 10;4:e1954. Epub 2016 May 10.

Groningen Institute for Evolutionary Life Sciences, University of Groningen , Groningen , the Netherlands.

The integration of invasive species into native food webs represent multifarious dynamics of ecological and evolutionary processes. We document incorporation of Prunus serotina (black cherry) into native insect food webs. We find that P. serotina harbours a herbivore community less dense but more diverse than its native relative, P. padus (bird cherry), with similar proportions of specialists and generalists. While herbivory on P. padus remained stable over the past century, that on P. serotina gradually doubled. We show that P. serotina may have evolved changes in investment in cyanogenic glycosides compared with its native range. In the leaf beetle Gonioctena quinquepunctata, recently shifted from native Sorbus aucuparia to P. serotina, we find divergent host preferences on Sorbus- versus Prunus-derived populations, and weak host-specific differentiation among 380 individuals genotyped for 119 SNP loci. We conclude that evolutionary processes may generate a specialized herbivore community on an invasive plant, allowing prognoses of reduced invasiveness over time. On the basis of the results presented here, we would like to caution that manual control might have the adverse effect of a slowing down of processes of adaptation, and a delay in the decline of the invasive character of P. serotina.
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http://dx.doi.org/10.7717/peerj.1954DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4867706PMC
May 2016

Antistaphylococcal Prenylated Acylphoroglucinol and Xanthones from Kielmeyera variabilis.

J Nat Prod 2016 Mar 22;79(3):470-6. Epub 2016 Feb 22.

Department of Organic Chemistry, Institute of Chemistry, São Paulo State University , Prof. Francisco Degni 55, Araraquara, 14800-900, Brazil.

Bioactivity-guided fractionation of the EtOH extract of the branches of Kielmeyera variabilis led to the isolation of a new acylphoroglucinol (1), which was active against all the MRSA strains tested herein, with pronounced activity against strain EMRSA-16. Compound 1 displayed an MIC of 0.5 mg/L as compared with an MIC of 128 mg/L for the control antibiotic norfloxacin. The structure of the new compound was elucidated by 1D and 2D NMR spectroscopic analysis and mass spectrometry, and experimental and calculated ECD were used to determine the absolute configurations. The compounds β-sitosterol (2), stigmasterol (3), ergost-5-en-3-ol (4), and osajaxanthone (5) also occurred in the n-hexane fraction. The EtOAc fraction contained nine known xanthones: 3,6-dihydroxy-1,4,8-trimethoxyxanthone (6), 3,5-dihydroxy-4-methoxyxanthone (7), 3,4-dihydroxy-6,8-dimethoxyxanthone (8), 3,4-dihydroxy-2-methoxyxanthone (9), 5-hydroxy-1,3-dimethoxyxanthone (10), 4-hydroxy-2,3-dimethoxyxanthone (11), kielcorin (12), 3-hydroxy-2-methoxyxanthone (13), and 2-hydroxy-1-methoxyxanthone (14), which showed moderate to low activity against the tested MRSA strains.
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http://dx.doi.org/10.1021/acs.jnatprod.5b00858DOI Listing
March 2016

A simple and rapid HPLC-DAD method for simultaneously monitoring the accumulation of alkaloids and precursors in different parts and different developmental stages of Catharanthus roseus plants.

J Chromatogr B Analyt Technol Biomed Life Sci 2016 Mar 23;1014:10-6. Epub 2016 Jan 23.

Plant Biotechnology Research Center, SJTU-Cornell Institute of Sustainable Agriculture and Biotechnology, Fudan-SJTU-Nottingham Plant Biotechnology R&D Center, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, PR China.

A rapid and simple reversed phase liquid chromatographic system has been developed for simultaneous analysis of terpenoid indole alkaloids (TIAs) and their precursors. This method allowed separation of 11 compounds consisting of eight TIAs (ajmalicine, serpentine, catharanthine, vindoline, vindolinine, vincristine, vinblastine, and anhydrovinblastine) and three related precursors i.e., tryptophan, tryptamine and loganin. The system has been applied for screening the TIAs and precursors in Catharanthus roseus plant extracts. In this study, different organs i.e., flowers, leaves, stems, and roots of C. roseus were investigated. The results indicate that TIAs and precursor accumulation varies qualitatively and quantitatively in different organs of C. roseus. The precursors showed much lower levels than TIAs in all organs. Leaves and flowers accumulate higher level of vindoline, catharanthine and anhydrovinblastine while roots have higher level of ajmalicine, vindolinine and serpentine. Moreover, the alkaloid profiles of leaves harvested at different ages and different growth stages were studied. The results show that the levels of monoindole alkaloids decreased while bisindole alkaloids increased with leaf aging and upon plant growth. The HPLC method has been successfully applied to detect TIAs and precursors in different types of C. roseus samples to facilitate further study of the TIA pathway and its regulation in C. roseus plants.
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http://dx.doi.org/10.1016/j.jchromb.2016.01.034DOI Listing
March 2016

Application of natural deep eutectic solvents to the extraction of anthocyanins from Catharanthus roseus with high extractability and stability replacing conventional organic solvents.

J Chromatogr A 2016 Feb 16;1434:50-6. Epub 2016 Jan 16.

Natural Products Laboratory, Institute of Biology, Leiden University, Sylviusweg, 2333 BE Leiden, The Netherlands. Electronic address:

Natural deep eutectic solvents (NADES) have attracted a great deal of attention in recent times as promising green media. They are generally composed of neutral, acidic or basic compounds that form liquids of high viscosity when mixed in certain molar ratio. Despite their potential, viscosity and acid or basic nature of some ingredients may affect the extraction capacity and stabilizing ability of the target compounds. To investigate these effects, extraction with a series of NADES was employed for the analysis of anthocyanins in flower petals of Catharanthus roseus in combination with HPLC-DAD-based metabolic profiling. Along with the extraction yields of anthocyanins their stability in NADES was also studied. Multivariate data analysis indicates that the lactic acid-glucose (LGH), and 1,2-propanediol-choline chloride (PCH) NADES present a similar extraction power for anthocyanins as conventional organic solvents. Furthermore, among the NADES employed, LGH exhibits an at least three times higher stabilizing capacity for cyanidins than acidified ethanol, which facilitates their extraction and analysis process. Comparing NADES to the conventional organic solvents, in addition to their reduced environmental impact, they proved to provide higher stability for anthocyanins, and therefore have a great potential as possible alternatives to those organic solvents in health related areas such as food, pharmaceuticals and cosmetics.
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http://dx.doi.org/10.1016/j.chroma.2016.01.037DOI Listing
February 2016

Zebrafish as a Model for Systems Medicine R&D: Rethinking the Metabolic Effects of Carrier Solvents and Culture Buffers Determined by (1)H NMR Metabolomics.

OMICS 2016 Jan 15;20(1):42-52. Epub 2015 Dec 15.

1 Natural Products Laboratory, Leiden University , Leiden, the Netherlands .

Zebrafish is a frequently employed model organism in systems medicine and biomarker discovery. A crosscutting fundamental question, and one that has been overlooked in the field, is the "system-wide" (omics) effects induced in zebrafish by metabolic solvents and culture buffers. Indeed, any bioactivity or toxicity test requires that the target compounds are dissolved in an appropriate nonpolar solvent or aqueous media. It is important to know whether the solvent or the buffer itself has an effect on the zebrafish model organism. We evaluated the effects of two organic carrier solvents used in research with zebrafish, as well as in drug screening: dimethyl sulfoxide (DMSO) and ethanol, and two commonly used aqueous buffers (egg water and Hank's balanced salt solution). The effects of three concentrations (0.01, 0.1, and 1%) of DMSO and ethanol were tested in the 5-day-old zebrafish embryo using proton nuclear magnetic resonance ((1)H NMR) based metabolomics. DMSO (1% and 0.1%, but not 0.01%) exposure significantly decreased the levels of adenosine triphosphate (ATP), betaine, alanine, histidine, lactate, acetate, and creatine (p < 0.05). By contrast, ethanol exposure did not alter the embryos' metabolome at any concentration tested. The two different aqueous media noted above impacted the zebrafish embryo metabolome as evidenced by changes in valine, alanine, lactate, acetate, betaine, glycine, glutamate, adenosine triphosphate, and histidine. These results show that DMSO has greater effects on the embryo metabolome than ethanol, and thus is used with caution as a carrier solvent in zebrafish biomarker research and oral medicine. Moreover, the DMSO concentration should not be higher than 0.01%. Careful attention is also warranted for the use of the buffers egg water and Hank's balanced salt solution in zebrafish. In conclusion, as zebrafish is widely used as a model organism in life sciences, metabolome changes induced by solvents and culture buffers warrant further attention for robust systems science, and precision biomarkers that will stand the test of time.
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http://dx.doi.org/10.1089/omi.2015.0119DOI Listing
January 2016

Biochemical characterization of embryogenic calli of Vanilla planifolia in response to two years of thidiazuron treatment.

Plant Physiol Biochem 2015 Nov 28;96:337-44. Epub 2015 Aug 28.

UMR "Peuplement végétaux et Bioagresseurs en Milieu Tropical", Faculté des Sciences et Technologies, Université de La Réunion, 15 Avenue René Cassin, Saint-Denis, La Réunion, France; LISBP-INSA Toulouse 135 Avenue de Rangueil, 31077 Toulouse, France. Electronic address:

Vanilla planifolia embryogenic calli were cultured for two years on a medium containing thidiazuron (TDZ). Due to the presence of TDZ, these calli were under permanent chemical treatment and the differentiation of adventitious shoots from protocorm-like-bodies (PLBs) was blocked. When embryogenic calli were transferred onto a medium without TDZ, shoot organogenesis and plantlet regeneration occurred. To gain better knowledge about the biochemical and molecular processes involved in the morphoregulatory role of TDZ, hormonal and metabolomic analyses were performed. Our results indicate that in the presence of TDZ, embryogenic calli contained a high amount of abscisic acid (ABA) essentially metabolized into abscisic acid glucosyl ester (ABAGE) and phaseic acid (PA), which was the most abundant. When transferred onto a medium without TDZ, shoot regeneration and development take place in four stages that include: embryogenic calli growth, differentiation of PLBs from meristmatic cells zones (MCZ), shoot organogenesis from PLBs and the elongation of well-formed shoots. From a hormonal perspective, the significant reduction in ABA metabolism and its readjustment in the ABAGE pathway triggered PLBs formation. However, this first morphogenesis was stimulated by a strong reduction in IAA metabolism. The organogenesis of PLBs into shoots is associated with an increase in ABA catabolism and a gradual shift in cellular metabolism towards shoot differentiation. Thus, the initiation of the elongation process in shoots is correlated with an alteration in metabolite composition, including an increase in energy reserves (sucrose/starch) and a rapid decrease in alanine content. Our data highlighted the relationship between endogenous hormone signalling, carbohydrate metabolism and shoot organogenesis in Orchid plants.
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http://dx.doi.org/10.1016/j.plaphy.2015.08.017DOI Listing
November 2015

Fungal endophytes of Vanilla planifolia across Réunion Island: isolation, distribution and biotransformation.

BMC Plant Biol 2015 Jun 14;15:142. Epub 2015 Jun 14.

Université de La Réunion, UMR PVBMT, 15 avenue René Cassin, CS 92003-97744, Saint Denis Cedex 9, La Réunion, France.

Background: The objective of the work was to characterize fungal endophytes from aerial parts of Vanilla planifolia. Also, to establish their biotransformation abilities of flavor-related metabolites. This was done in order to find a potential role of endophytes on vanilla flavors.

Results: Twenty three MOTUs were obtained, representing 6 fungal classes. Fungi from green pods were cultured on mature green pod based media for 30 days followed by (1)H NMR and HPLC-DAD analysis. All fungi from pods consumed metabolized vanilla flavor phenolics. Though Fusarium proliferatum was recovered more often (37.6% of the isolates), it is Pestalotiopsis microspora (3.0%) that increased the absolute amounts (quantified by (1)H NMR in μmol/g DW green pods) of vanillin (37.0 × 10(-3)), vanillyl alcohol (100.0 × 10(-3)), vanillic acid (9.2 × 10(-3)) and p-hydroxybenzoic acid (87.9 × 10(-3)) by significant amounts.

Conclusions: All plants studied contained endophytic fungi and the isolation of the endophytes was conducted from plant organs at nine sites in Réunion Island including under shade house and undergrowth conditions. Endophytic variation occured between cultivation practices and the type of organ. Given the physical proximity of fungi inside pods, endophytic biotransformation may contribute to the complexity of vanilla flavors.
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http://dx.doi.org/10.1186/s12870-015-0522-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4465486PMC
June 2015

Tailoring properties of natural deep eutectic solvents with water to facilitate their applications.

Food Chem 2015 Nov 3;187:14-9. Epub 2015 Apr 3.

Natural Products Laboratory, Institute of Biology, Leiden University, 2333 BE Leiden, The Netherlands. Electronic address:

Previously it was demonstrated that natural deep eutectic solvents (NADES) are promising green solvents for the extraction of natural products. However, despite their potential, an obvious disadvantage of NADES is the high viscosity. Here we explored the dilution effect on the structures and physicochemical properties of NADES and their improvements of applications using quercetin and carthamin. The results of FT-IR and (1)H NMR experiments demonstrated that there are intensive H-bonding interactions between the two components of NADES and dilution with water caused the interactions weaken gradually and even disappeared completely at around 50% (v/v) water addition. A small amount of water could reduce the viscosity of NADES to the range of water and increase the conductivity by up to 100 times for some NADES. This study provides the basis for modulating NADES in a controllable way for their applications in food processing, enzyme reactions, pharmaceuticals and cosmetics.
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http://dx.doi.org/10.1016/j.foodchem.2015.03.123DOI Listing
November 2015