Molecules

276 KiB

Open AccessCommunication

Brazilin Inhibits Growth and Induces Apoptosis in Human Glioblastoma Cells

by Dae-Young Lee, Mi-Kyoung Lee, Geum-Soog Kim, Hyung-Jun Noh and Min-Ho Lee

Molecules 2013, 18(2), 2449-2457; https://doi.org/10.3390/molecules18022449 - 21 Feb 2013

Cited by 55 | Viewed by 6892

Brazilin, isolated from the methanol extract of the heart wood of Caesalpinia sappan, sensitizes cancer cells to apoptosis. Glioblastoma multiforme (GBM), which accounts for most cases of central nervous system malignancy, has a very poor prognosis and lacks effective therapeutic interventions. We, [...] Read more.

Brazilin, isolated from the methanol extract of the heart wood of Caesalpinia sappan, sensitizes cancer cells to apoptosis. Glioblastoma multiforme (GBM), which accounts for most cases of central nervous system malignancy, has a very poor prognosis and lacks effective therapeutic interventions. We, therefore, investigated the effects of different concentrations of and different periods of exposure to brazilin on cell proliferation and apoptosis in the glioma U87 cell line. Cell proliferation was investigated by MTT assays and growth curve analysis, apoptosis was assessed by FACS analysis and western blot studies. Brazilin showed dose-dependent inhibition of cell proliferation and induction of apoptosis in glioma cells. It also increased the ratio of cleaved poly-(ADP)-ribose polymerase and decreased the expression of caspase-3 and caspase-7. Full article

(This article belongs to the Section Medicinal Chemistry)

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310 KiB

Open AccessArticle

The Tandem Ring Opening/Ring Closing Metathesis Route to Oxaspirocycles: An Approach to Phelligridin G

by Harold D. Cooper and Dennis L. Wright

Molecules 2013, 18(2), 2438-2448; https://doi.org/10.3390/molecules18022438 - 21 Feb 2013

Cited by 11 | Viewed by 6391

Abstract

Phelligridin G is an unusual natural product that contains an embedded spiro-fused furanone core. We have investigated two furan-based synthetic approaches towards the spirocyclic core structure of this natural product from readily available 2-phenylfurans. Although initial studies involving an oxidative cyclization were unsuccessful, [...] Read more.

Phelligridin G is an unusual natural product that contains an embedded spiro-fused furanone core. We have investigated two furan-based synthetic approaches towards the spirocyclic core structure of this natural product from readily available 2-phenylfurans. Although initial studies involving an oxidative cyclization were unsuccessful, we were ultimately able to access this key system through a sequential intermolecular furan Diels-Alder reaction followed by a metathesis-based reorganization. A related approach led to an expanded C ring to form spiro-fused pyran spirocycles. Full article

(This article belongs to the Special Issue Spiro Compounds)

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256 KiB

Open AccessArticle

Sonolytic and Silent Polymerization of Methacrlyic Acid Butyl Ester Catalyzed by a New Onium Salt with bis-Active Sites in a Biphasic System — A Comparative Investigation

by Perumberkandgai A. Vivekanand, Maw-Ling Wang and Yu-Ming Hsieh

Molecules 2013, 18(2), 2419-2437; https://doi.org/10.3390/molecules18022419 - 21 Feb 2013

Cited by 12 | Viewed by 5960

Abstract

Currently, ingenious new analytical and process experimental techniques which are environmentally benign techniques, viz., ultrasound irradiation, have become immensely popular in promoting various reactions. In this work, a novel soluble multi-site phase transfer catalyst (PTC) viz., 1,4-bis-(propylmethyleneammounium chloride)benzene (BPMACB) was synthesized [...] Read more.

Currently, ingenious new analytical and process experimental techniques which are environmentally benign techniques, viz., ultrasound irradiation, have become immensely popular in promoting various reactions. In this work, a novel soluble multi-site phase transfer catalyst (PTC) viz., 1,4-bis-(propylmethyleneammounium chloride)benzene (BPMACB) was synthesized and its catalytic efficiency was assessed by observing the kinetics of sonolytic polymerization of methacrylic acid butyl ester (MABE) using potassium persulphate (PPS) as an initiator. The ultrasound–multi-site phase transfer catalysis (US-MPTC)-assisted polymerization reaction was compared with the silent (non-ultrasonic) polymerization reaction. The effects of the catalyst and various reaction parameters on the catalytic performance were in detail investigated by following the kinetics of polymerization of MABE in an ethyl acetate-water biphasic system. From the detailed kinetic investigation we propose a plausible mechanism. Further the kinetic results demonstrate clearly that ultrasound-assisted phase-transfer catalysis significantly increased the reaction rate when compared to silent reactions. Notably, this environmentally benign and cost-effective process has great potential to be applied in various polymer industries. Full article

(This article belongs to the Special Issue Phase Transfer Catalysis)

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510 KiB

Open AccessArticle

7-Methoxytacrine-Adamantylamine Heterodimers as Cholinesterase Inhibitors in Alzheimer’s Disease Treatment — Synthesis, Biological Evaluation and Molecular Modeling Studies

by Katarina Spilovska, Jan Korabecny, Jan Kral, Anna Horova, Kamil Musilek, Ondrej Soukup, Lucie Drtinova, Zuzana Gazova, Katarina Siposova and Kamil Kuca

Molecules 2013, 18(2), 2397-2418; https://doi.org/10.3390/molecules18022397 - 20 Feb 2013

Cited by 71 | Viewed by 10012

Abstract

A structural series of 7-MEOTA-adamantylamine thioureas was designed, synthesized and evaluated as inhibitors of human acetylcholinesterase (hAChE) and human butyrylcholinesterase (hBChE). The compounds were prepared based on the multi-target-directed ligand strategy with different linker lengths (n = 2–8) joining the well-known NMDA antagonist [...] Read more.

A structural series of 7-MEOTA-adamantylamine thioureas was designed, synthesized and evaluated as inhibitors of human acetylcholinesterase (hAChE) and human butyrylcholinesterase (hBChE). The compounds were prepared based on the multi-target-directed ligand strategy with different linker lengths (n = 2–8) joining the well-known NMDA antagonist adamantine and the hAChE inhibitor 7-methoxytacrine (7-MEOTA). Based on in silico studies, these inhibitors proved dual binding site character capable of simultaneous interaction with the peripheral anionic site (PAS) of hAChE and the catalytic active site (CAS). Clearly, these structural derivatives exhibited very good inhibitory activity towards hBChE resulting in more selective inhibitors of this enzyme. The most potent cholinesterase inhibitor was found to be thiourea analogue 14 (with an IC₅₀ value of 0.47 µM for hAChE and an IC₅₀ value of 0.11 µM for hBChE, respectively). Molecule 14 is a suitable novel lead compound for further evaluation proving that the strategy of dual binding site inhibitors might be a promising direction for development of novel AD drugs. Full article

(This article belongs to the Section Medicinal Chemistry)

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821 KiB

Open AccessArticle

Synthesis and Crystal Structures of N-Substituted Pyrazolines

by Wan-Sin Loh, Ching Kheng Quah, Tze Shyang Chia, Hoong-Kun Fun, Majal Sapnakumari, Badiadka Narayana and Balladka Kunhanna Sarojini

Molecules 2013, 18(2), 2386-2396; https://doi.org/10.3390/molecules18022386 - 20 Feb 2013

Cited by 11 | Viewed by 6438

Abstract

Four pyrazole compounds, 3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbaldehyde (1), 5-(4-bromophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehyde (2), 1-[5-(4-chlorophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone (3) and 1-[3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl]propan-1-one (4), have been prepared by condensing chalcones with hydrazine hydrate in the presence of aliphatic acids, [...] Read more.

Four pyrazole compounds, 3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazole-1-carbaldehyde (1), 5-(4-bromophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehyde (2), 1-[5-(4-chlorophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone (3) and 1-[3-(4-fluorophenyl)-5-phenyl-4,5-dihydro-1H-pyrazol-1-yl]propan-1-one (4), have been prepared by condensing chalcones with hydrazine hydrate in the presence of aliphatic acids, namely formic acid, acetic acid and propionic acid. The structures were characterized by X-ray single crystal structure determination. The dihedral angles formed between the pyrazole and the fluoro-substituted rings are 4.64(7)° in 1, 5.3(4)° in 2 and 4.89(6)° in 3. In 4, the corresponding angles for molecules A and molecules B are 10.53(10)° and 9.78(10)°, respectively. Full article

(This article belongs to the Section Organic Chemistry)

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Open AccessArticle

Free Radical Scavenging Activity of Kielmeyera variabilis (Clusiaceae)

by Aline Coqueiro, Luis Octávio Regasini, Scheila Cristina Gutkoski Skrzek, Marcos Marçal Ferreira Queiroz, Dulce Helena Siqueira Silva and Vanderlan Da Silva Bolzani

Molecules 2013, 18(2), 2376-2385; https://doi.org/10.3390/molecules18022376 - 19 Feb 2013

Cited by 19 | Viewed by 6322

Abstract

As part of our ongoing research on antioxidant agents from Brazilian flora, we screened the free radical scavenging activity of two extracts and eight fractions of Kielmeyera variabilis (Clusiaceae) using DPPH^· (2,2-diphenyl-1-picrylhydrazyl-hydrate) and ABTS^·⁺ [2,2'-azinobis(3-ethylenebenzothiazoline-6-sulfonic acid)] colorimetric assays. The ethyl [...] Read more.

As part of our ongoing research on antioxidant agents from Brazilian flora, we screened the free radical scavenging activity of two extracts and eight fractions of Kielmeyera variabilis (Clusiaceae) using DPPH^· (2,2-diphenyl-1-picrylhydrazyl-hydrate) and ABTS^·⁺ [2,2'-azinobis(3-ethylenebenzothiazoline-6-sulfonic acid)] colorimetric assays. The ethyl acetate and n-butanol fractions of the leaves of K. variabilis displayed the strongest activity (IC₅₀ of 3.5 ± 0.3 and 4.4 ± 0.2 μg mL⁻¹ for DPPH^· and 6.6 ± 0.4 and 3.1 ± 0.1 μg mL⁻¹ for ABTS^·⁺, respectively). Chromatographic fractionation of the most potent fractions led to identification of three flavonols with previously described antioxidant activity, quercitrin (1), quercetin-3-O-b-glucoside (3), and quercetin-3-O-b-galactoside (4), and of one biflavone, podocarpusflavone A (2). This is the first time that the presence of these flavonoids in Kielmeyera variabilis has been reported. Full article

(This article belongs to the Section Natural Products Chemistry)

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Open AccessReview

Techniques for Analysis of Plant Phenolic Compounds

by Ali Khoddami, Meredith A. Wilkes and Thomas H. Roberts

Molecules 2013, 18(2), 2328-2375; https://doi.org/10.3390/molecules18022328 - 19 Feb 2013

Cited by 933 | Viewed by 66202

Abstract

Phenolic compounds are well-known phytochemicals found in all plants. They consist of simple phenols, benzoic and cinnamic acid, coumarins, tannins, lignins, lignans and flavonoids. Substantial developments in research focused on the extraction, identification and quantification of phenolic compounds as medicinal and/or dietary molecules [...] Read more.

Phenolic compounds are well-known phytochemicals found in all plants. They consist of simple phenols, benzoic and cinnamic acid, coumarins, tannins, lignins, lignans and flavonoids. Substantial developments in research focused on the extraction, identification and quantification of phenolic compounds as medicinal and/or dietary molecules have occurred over the last 25 years. Organic solvent extraction is the main method used to extract phenolics. Chemical procedures are used to detect the presence of total phenolics, while spectrophotometric and chromatographic techniques are utilized to identify and quantify individual phenolic compounds. This review addresses the application of different methodologies utilized in the analysis of phenolic compounds in plant-based products, including recent technical developments in the quantification of phenolics. Full article

(This article belongs to the Special Issue Methods in Polyphenol Analysis)

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1038 KiB

Open AccessReview

3-Substituted Prolines: From Synthesis to Structural Applications, from Peptides to Foldamers

by Céline Mothes, Cécile Caumes, Alexandre Guez, Héloïse Boullet, Thomas Gendrineau, Sylvain Darses, Nicolas Delsuc, Roba Moumné, Benoit Oswald, Olivier Lequin and Philippe Karoyan

Molecules 2013, 18(2), 2307-2327; https://doi.org/10.3390/molecules18022307 - 19 Feb 2013

Cited by 38 | Viewed by 11940

Abstract

Among the twenty natural proteinogenic amino acids, proline is unique as its secondary amine forms a tertiary amide when incorporated into biopolymers, thus preventing hydrogen bond formation. Despite the lack of hydrogen bonds and thanks to conformational restriction of flexibility linked to the [...] Read more.

Among the twenty natural proteinogenic amino acids, proline is unique as its secondary amine forms a tertiary amide when incorporated into biopolymers, thus preventing hydrogen bond formation. Despite the lack of hydrogen bonds and thanks to conformational restriction of flexibility linked to the pyrrolidine ring, proline is able to stabilize peptide secondary structures such as b-turns or polyproline helices. These unique conformational properties have aroused a great interest in the development of proline analogues. Among them, proline chimeras are tools combining the proline restriction of flexibility together with the information brought by natural amino acids side chains. This review will focus on the chemical syntheses of 3-substituted proline chimeras of potential use for peptide syntheses and as potential use as tools for SAR studies of biologically active peptides and the development of secondary structure mimetics. Their influence on peptide structure will be briefly described. Full article

(This article belongs to the Special Issue Chemical Protein and Peptide Synthesis)

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364 KiB

Open AccessArticle

Neglschisandrins E–F: Two New Lignans and Related Cytotoxic Lignans from Schisandra neglecta

by Min Chen, Xiumei Xu, Bing Xu, Panpan Yang, Zhihua Liao, Susan L. Morris-Natschke, Kuo-Hsiung Lee and Daofeng Chen

Molecules 2013, 18(2), 2297-2306; https://doi.org/10.3390/molecules18022297 - 19 Feb 2013

Cited by 19 | Viewed by 6163

Abstract

Phytochemical investigation of an ethanolic extract of stems of Schisandra neglecta led to the isolation and identification of two new dibenzocyclooctadiene lignans, designated neglschisandrins E (1) and F (2), and thirteen known lignans. All structures and stereochemistries were determined [...] Read more.

Phytochemical investigation of an ethanolic extract of stems of Schisandra neglecta led to the isolation and identification of two new dibenzocyclooctadiene lignans, designated neglschisandrins E (1) and F (2), and thirteen known lignans. All structures and stereochemistries were determined by spectroscopic methods, including 2D-NMR techniques. The isolates were evaluated for in vitro cytotoxic activity. Among them, compounds 2–6 exhibited moderate to weak cytotoxicity against the human colorectal carcinoma HCT-8 cell line with EC₅₀ values of 7.33~19.8 μg/mL. In addition, compounds 2–4 also exhibited marginal cytotoxicity against the human lung carcinoma A549 cell line with EC₅₀ values of 11.8~15.0 μg/mL. Full article

(This article belongs to the Section Natural Products Chemistry)

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Open AccessArticle

Enthalpy/Entropy Contributions to Conformational KIEs: Theoretical Predictions and Comparison with Experiment

by Aaron Fong, Matthew P. Meyer and Daniel J. O'Leary

Molecules 2013, 18(2), 2281-2296; https://doi.org/10.3390/molecules18022281 - 18 Feb 2013

Cited by 8 | Viewed by 6418

Abstract

Previous theoretical studies of Mislow’s doubly-bridged biphenyl ketone 1 and dihydrodimethylphenanthrene 2 have determined significant entropic contributions to their normal (1) and inverse (2) conformational kinetic isotope effects (CKIEs). To broaden our investigation, we have used density functional methods [...] Read more.

Previous theoretical studies of Mislow’s doubly-bridged biphenyl ketone 1 and dihydrodimethylphenanthrene 2 have determined significant entropic contributions to their normal (1) and inverse (2) conformational kinetic isotope effects (CKIEs). To broaden our investigation, we have used density functional methods to characterize the potential energy surfaces and vibrational frequencies for ground and transition structures of additional systems with measured CKIEs, including [2.2]-metaparacyclophane-d (3), 1,1'-binaphthyl (4), 2,2'-dibromo-[1,1'-biphenyl]-4,4'-dicarboxylic acid (5), and the 2-(N,N,N-trimethyl)-2'-(N,N-dimethyl)-diaminobiphenyl cation (6). We have also computed CKIEs in a number of systems whose experimental CKIEs are unknown. These include analogs of 1 in which the C=O groups have been replaced with CH₂ (7), O (8), and S (9) atoms and ring-expanded variants of 2 containing CH₂ (10), O (11), S (12), or C=O (13) groups. Vibrational entropy contributes to the CKIEs in all of these systems with the exception of cyclophane 3, whose isotope effect is predicted to be purely enthalpic in origin and whose Bigeleisen-Mayer ZPE term is equivalent to ΔΔ H^‡. There is variable correspondence between these terms in the other molecules studied, thus identifying additional examples of systems in which the Bigeleisen-Mayer formalism does not correlate with ΔH/ΔS dissections. Full article

(This article belongs to the Collection Isotope Effects)

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Open AccessArticle

Quenching of Tryptophan Fluorescence in the Presence of 2,4-DNP, 2,6-DNP, 2,4-DNA and DNOC and Their Mechanism of Toxicity

by Cristina-Amalia Dumitraş Huţanu, Marius Zaharia and Olga Pintilie

Molecules 2013, 18(2), 2266-2280; https://doi.org/10.3390/molecules18022266 - 18 Feb 2013

Cited by 9 | Viewed by 8140

Abstract

Although they are widely used as insecticides, acaricides and fungicides in the agriculture or as raw materials in the dye industry, dinitrophenols (DNPs) are extremely noxious, death cases having been registered. These compounds produce cataracts, lower leucocyte levels, disturb the general metabolism and [...] Read more.

Although they are widely used as insecticides, acaricides and fungicides in the agriculture or as raw materials in the dye industry, dinitrophenols (DNPs) are extremely noxious, death cases having been registered. These compounds produce cataracts, lower leucocyte levels, disturb the general metabolism and can cause cancer. It is also assumed that DNPs hinder the proton translocation through the mitochondrial inner membrane and therefore inhibit oxidative phosphorylation. Their fluorescence quenching properties can help understand and explain their toxicity. Fluorescence quenching of tryptophan was tested using different dinitrophenols such as 2,4-dinitrophenol (2,4-DNP), 4,6-dinitro-orthocresol (DNOC), 2-[(2,4-dinitrophenyl)amino]acetic acid (GlyDNP), 2-(1-methyl-heptyl)-4.6-dinitrophenyl crotonate (Karathan), 2-amino-5-[(1-((carboxymethyl)amino)-3-((2,4-dinitrophenyl)thio)-1-oxopropan-2-yl)amino]-5-oxopentanoic acid (SDN GSH), 2,4-dinitroanisole (2,4-DNA) and 2,4-dinitrobenzoic acid (2,4-DNB). 2,4-DNP and DNOC showed the highest tryptophan fluorescence quenching constant values, these being also the most toxic compounds. The electronic chemical potential value of the most stable complex of 2,4-DNP-with tryptophan is higher than the values of the electronic chemical potentials of complexes corresponding to the derivatives. Full article

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Open AccessArticle

Characterization of Proanthocyanidins in Stems of Polygonum multiflorum Thunb as Strong Starch Hydrolase Inhibitors

by Hongyu Wang, Lixia Song, Shengbao Feng, Yuancai Liu, Gang Zuo, Fuli Lai, Guangyuan He, Mingjie Chen and Dejian Huang

Molecules 2013, 18(2), 2255-2265; https://doi.org/10.3390/molecules18022255 - 18 Feb 2013

Cited by 33 | Viewed by 7694

Abstract

Characterzation of polyphenolic compounds in the stems of P. multiflorum was conducted using HPLC, high resolution LC-MS and LC-MSⁿ. Proanthocyanidins in particular were isolated in 4.8% yield using solvent extraction followed by Sephadex LH-20 fractionation. HPLC analysis using a diol column [...] Read more.

Characterzation of polyphenolic compounds in the stems of P. multiflorum was conducted using HPLC, high resolution LC-MS and LC-MSⁿ. Proanthocyanidins in particular were isolated in 4.8% yield using solvent extraction followed by Sephadex LH-20 fractionation. HPLC analysis using a diol column revealed oligomers (from dimer to nonamer) as minor components, with (epi)catechin monomeric units predominating, and oligomers with higher degree of polymerization being dominant. Thiolysis treatment of the proanthocyanidins using mercaptoacetic acid produced thioether derivatives of (epi)catechin as the major product and a mean value of the degree of polymerization of 32.6 was estimated from the ratio of terminal and extension units of the (epi)catechin. The isolated proanthocyanidins were shown to strongly inhibit α-amylase with an acarbose equivalence (AE) value of 1,954.7 µmol AE/g and inhibit α-glucosidase with an AE value of 211.1 µmol AE/g. Full article

(This article belongs to the Section Natural Products Chemistry)

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Open AccessArticle

Growth of Fullerene Fragments Using the Diels-Alder Cycloaddition Reaction: First Step towards a C₆₀ Synthesis by Dimerization

by Martha Mojica, Francisco Méndez and Julio A. Alonso

Molecules 2013, 18(2), 2243-2254; https://doi.org/10.3390/molecules18022243 - 13 Feb 2013

Cited by 6 | Viewed by 5702

Abstract

Density Functional Theory has been used to model the Diels-Alder reactions of the fullerene fragments triindenetriphenilene and pentacyclopentacorannulene with ethylene and 1,3-butadiene. The purpose is to prove the feasibility of using Diels-Alder cycloaddition reactions to grow fullerene fragments step by step, and to [...] Read more.

Density Functional Theory has been used to model the Diels-Alder reactions of the fullerene fragments triindenetriphenilene and pentacyclopentacorannulene with ethylene and 1,3-butadiene. The purpose is to prove the feasibility of using Diels-Alder cycloaddition reactions to grow fullerene fragments step by step, and to dimerize fullerene fragments, as a way to obtain C₆₀. The dienophile character of the fullerene fragments is dominant, and the reaction of butadiene with pentacyclopentacorannulene is favored. Full article

(This article belongs to the Special Issue Diels-Alder Reaction)

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Open AccessArticle

New Spiral γ-Lactone Enantiomers from the Plant Endophytic Fungus Pestalotiopsis foedan

by Xiao-Long Yang and Zhuang-Zhuang Li

Molecules 2013, 18(2), 2236-2242; https://doi.org/10.3390/molecules18022236 - 11 Feb 2013

Cited by 14 | Viewed by 5327

Abstract

(−)-(4S, 8S)-Foedanolide (1a) and (+)-(4R, 8R)-foedanolide (1b), a pair of new spiro-γ-lactone enantiomers, were isolated from the fermentation broth of the plant endophytic fungus Pestalotiopsis foedan by HPLC using a chiral [...] Read more.

(−)-(4S, 8S)-Foedanolide (1a) and (+)-(4R, 8R)-foedanolide (1b), a pair of new spiro-γ-lactone enantiomers, were isolated from the fermentation broth of the plant endophytic fungus Pestalotiopsis foedan by HPLC using a chiral column, achieving over 7% ee. Their structures and absolute configurations were determined on the basis of extensive analysis of NMR spectra combined with computational methods via calculation of the electronic circular dichroism (ECD) and optical rotation (OR). Compounds 1a and 1b showed moderate activities against HeLa, A-549, U-251, HepG2 and MCF-7 tumor cell lines. Full article

(This article belongs to the Section Natural Products Chemistry)

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Open AccessArticle

Preparation of an Immunoaffinity Column with Amino-Silica Gel Microparticles and Its Application in Sample Cleanup for Aflatoxin Detection in Agri-Products

by Fei Ma, Ran Chen, Peiwu Li, Qi Zhang, Wen Zhang and Xiaofeng Hu

Molecules 2013, 18(2), 2222-2235; https://doi.org/10.3390/molecules18022222 - 11 Feb 2013

Cited by 41 | Viewed by 6340

Abstract

This study established an immunoaffinity column for selective extraction of aflatoxins in agri-products. Specifically, the immunoaffinity column was developed by covalently coupling monoclonal antibody 1C11 against aflatoxins to amino-silica gel microparticles and then packing these into a cartridge. The extraction conditions were thoroughly [...] Read more.

This study established an immunoaffinity column for selective extraction of aflatoxins in agri-products. Specifically, the immunoaffinity column was developed by covalently coupling monoclonal antibody 1C11 against aflatoxins to amino-silica gel microparticles and then packing these into a cartridge. The extraction conditions were thoroughly optimized in terms of loading, washing and eluting solutions. Under the optimal conditions, the immunoaffinity column had a capacity of 200 ng of aflatoxins. The detection limits (S/N = 3) for aflatoxin G₁, B₁, G₂ and B₂ were 0.03, 0.07, 0.05 and 0.09 μg·kg⁻¹, and the corresponding quantification limits (S/N = 10) were 0.10, 0.25, 0.18 and 0.30 μg·kg⁻¹, respectively. The recoveries of aflatoxins in samples were 90.1%–104.4% and RSDs were <4.4%. The developed method was further applied to the determination of aflatoxins in peanut, vegetable oil and tea samples, and the results indicated that peanut (26.9%), vegetable oils (28.0%) and tea (5.3%) samples were contaminated with aflatoxins, with levels ranging from 0.49 to 20.79 μg·kg⁻¹. Full article

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Open AccessArticle

An Efficient Chemoselective Reduction of Furan Series Unsaturated Dinitriles

by Pavel Bobal and Janette Bobalova

Molecules 2013, 18(2), 2212-2221; https://doi.org/10.3390/molecules18022212 - 11 Feb 2013

Cited by 8 | Viewed by 6733

Abstract

An efficient reduction of double bonds conjugated with nitrile groups and acid or base sensitive furan rings with 2-phenylbenzimidazoline generated in situ has been successfully accomplished with high yields and excellent selectivity. The employed reducing agent was prepared in one step from ordinary [...] Read more.

An efficient reduction of double bonds conjugated with nitrile groups and acid or base sensitive furan rings with 2-phenylbenzimidazoline generated in situ has been successfully accomplished with high yields and excellent selectivity. The employed reducing agent was prepared in one step from ordinary chemicals. The other advantages of the presented method include mild and convenient reaction conditions, a benign and cost effective reagent, simple work-up and separation of the products. As this process does neither affect cyano and nitro groups nor furan rings, it is a valuable alternative when metal-catalyzed hydrogenations or borohydride reductions have failed. Full article

(This article belongs to the Section Organic Chemistry)

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Open AccessArticle

Gelam Honey Protects against Gamma-Irradiation Damage to Antioxidant Enzymes in Human Diploid Fibroblasts

by Tengku Ahbrizal Farizal Tengku Ahmad, Zakiah Jubri, Nor Fadilah Rajab, Khairuddin Abdul Rahim, Yasmin Anum Mohd Yusof and Suzana Makpol

Molecules 2013, 18(2), 2200-2211; https://doi.org/10.3390/molecules18022200 - 11 Feb 2013

Cited by 24 | Viewed by 5829

Abstract

The present study was designed to determine the radioprotective effects of Malaysian Gelam honey on gene expression and enzyme activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) of human diploid fibroblasts (HDFs) subjected to gamma-irradiation. Six groups of HDFs were [...] Read more.

The present study was designed to determine the radioprotective effects of Malaysian Gelam honey on gene expression and enzyme activity of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) of human diploid fibroblasts (HDFs) subjected to gamma-irradiation. Six groups of HDFs were studied: untreated control, irradiated HDFs, Gelam honey-treated HDFs and HDF treated with Gelam honey pre-, during- and post-irradiation. HDFs were treated with 6 mg/mL of sterilized Gelam honey (w/v) for 24 h and exposed to 1 Gray (Gy) of gamma rays at the dose rate of 0.25 Gy/min. Gamma-irradiation was shown to down-regulate SOD1, SOD2, CAT and GPx1 gene expressions (p < 0.05). Conversely, HDFs treated with Gelam honey alone showed up-regulation of all genes studied. Similarly, SOD, CAT and GPx enzyme activities in HDFs decreased with gamma-irradiation and increased when cells were treated with Gelam honey (p < 0.05). Furthermore, of the three different stages of study treatment, pre-treatment with Gelam honey caused up-regulation of SOD1, SOD2 and CAT genes expression and increased the activity of SOD and CAT. As a conclusion, Gelam honey modulates the expression of antioxidant enzymes at gene and protein levels in irradiated HDFs indicating its potential as a radioprotectant agent. Full article

(This article belongs to the Section Natural Products Chemistry)

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Open AccessArticle

Anti-Escherichia coli O157:H7 Properties of Purple Prairie Clover and Sainfoin Condensed Tannins

by Xiu-Li Liu, Yong-Qing Hao, Long Jin, Zhong-Jun Xu, Tim A. McAllister and Yuxi Wang

Molecules 2013, 18(2), 2183-2199; https://doi.org/10.3390/molecules18022183 - 8 Feb 2013

Cited by 63 | Viewed by 6151

Abstract

Condensed tannins (CT) from purple prairie clover (PPC; Dalea purpurea Vent.) and sainfoin (SF; Onobrychis viciifolia) were assessed for anti-Escherichia coli activity by comparing their ability to react with proteins and liposome, cause cell aggregation, and alter outer membrane (OM) morphology [...] Read more.

Condensed tannins (CT) from purple prairie clover (PPC; Dalea purpurea Vent.) and sainfoin (SF; Onobrychis viciifolia) were assessed for anti-Escherichia coli activity by comparing their ability to react with proteins and liposome, cause cell aggregation, and alter outer membrane (OM) morphology and permeability. The PPC CT had greater (P < 0.01) protein-precipitating capacity than SF CT using either bovine serum albumin or ribulose 1,5-disphosphate carboxylase as model proteins. Minimum inhibitory concentration of PPC CT for two strains of E. coli and five strains of E. coli O157:H7 was four to six times lower than that of SF CT. E. coli exposed to 10 µg/mL of both CT had higher (P < 0.05) OM permeability than controls and was greater (P < 0.05) for PPC than for SF CT. Addition of both CT at 50 and 200 µg/mL caused cell aggregation which was more evident (P < 0.05) for PPC than for SF CT. Transmission electron microscopy showed electron dense material on the cell surface when cells were exposed to 50 µg/mL of PPC CT. The greater anti-E. coli activity of PPC than SF CT was due to its enhanced ability to precipitate protein that increased OM permeability and promoted cell aggregation. Full article

(This article belongs to the Section Natural Products Chemistry)

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Open AccessArticle

Antibacterial/Antifungal Activity and Synergistic Interactions between Polyprenols and Other Lipids Isolated from Ginkgo Biloba L. Leaves

by Ran Tao, Cheng-Zhang Wang and Zhen-Wu Kong

Molecules 2013, 18(2), 2166-2182; https://doi.org/10.3390/molecules18022166 - 7 Feb 2013

Cited by 86 | Viewed by 8511

Abstract

Polyprenols separated from lipids are promising new components from Ginkgo biloba L. leaves (GBL). In this paper, ginkgo lipids were isolated by extraction with petroleum ether, saponification, and molecular distillation. Eight known compounds: isophytol (1), nerolidol (2), linalool ( [...] Read more.

Polyprenols separated from lipids are promising new components from Ginkgo biloba L. leaves (GBL). In this paper, ginkgo lipids were isolated by extraction with petroleum ether, saponification, and molecular distillation. Eight known compounds: isophytol (1), nerolidol (2), linalool (3), β-sitosterol acetate (4), β-sitosterol (5), stigmasterol (6), ergosterol (7), β-sitosterol-3-O-β-D-glucopyranoside (8) and Ginkgo biloba polyprenols (GBP) were separated from GBL by chromatography and identified mainly by NMR. The separated and identified compounds 1, 2 and 3 are reported here for the first time in GBL. The 3D-DAD-HPLC-chromatogram (190–232 nm) of GBP was recorded. This study provides new evidence as there are no previous reports on antibacterial/antifungal activities and synergistic interactions between GBP and the compounds separated from GBL lipids against Salmonella enterica, Staphylocococus aureus and Aspergillus niger. Nerolidol (2) showed the highest activity among all the tested samples and of all mixture groups tested the GBP with isophytol (1) mixture had the strongest synergistic effect against Salmonella enterica among the three tested strains. A proportion of isophytol and GBP of 38.19%:61.81% (wt/wt) was determined by mixture design as the optimal proportion for the synergistic effect of GBP with isophytol against Salmonella enterica. Full article

(This article belongs to the Section Natural Products Chemistry)

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Open AccessArticle

Volatiles and Water- and Fat-Soluble Precursors of Saanen Goat and Cross Suffolk Lamb Flavour

by Marta Madruga, Ingrid Dantas, Angela Queiroz, Luciana Brasil and Yuri Ishihara

Molecules 2013, 18(2), 2150-2165; https://doi.org/10.3390/molecules18022150 - 7 Feb 2013

Cited by 31 | Viewed by 5975

Abstract

This paper evaluates the concentrations of water- and fat-soluble precursors of meat flavour, with the aim of characterising the effect of species on the volatile profile of grilled goat and lamb meat. Compared to goat, lamb meat had higher levels of saturated fatty [...] Read more.

This paper evaluates the concentrations of water- and fat-soluble precursors of meat flavour, with the aim of characterising the effect of species on the volatile profile of grilled goat and lamb meat. Compared to goat, lamb meat had higher levels of saturated fatty acids—SFA, monounsaturated fatty acids—MUFA and polyunsaturated fatty acids—PUFA and similar levels of sugars and free amino acids, except for lysine and glycine, which were higher in goat. Major differences were detected in lipid-derived volatiles; only pyrazine, thiazole, and some Strecker aldehydes were at different concentrations in these species. Volatile compounds derived from the oxidation of linoleic acid were at higher levels in meat from lamb due to the higher concentration of the latter, while compounds formed from α-linolenic acid were at higher levels in goat. It can be concluded that lamb meat has a stronger flavour profile compared to goat meat because it has the highest concentrations of lipid-derived volatile compounds, primarily straight saturated alkanals, pyrazines and thiazole. Full article

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Open AccessArticle

Anti-Helicobacter pylori and Urease Inhibition Activities of Some Traditional Medicinal Plants

by Muhammad Amin, Farooq Anwar, Fauqia Naz, Tahir Mehmood and Nazamid Saari

Molecules 2013, 18(2), 2135-2149; https://doi.org/10.3390/molecules18022135 - 7 Feb 2013

Cited by 98 | Viewed by 11257

Abstract

Different parts of Acacia nilotica (L.) Delile, Calotropis procera (Aiton) W.T. Aiton, Adhatoda vasica Nees, Fagoniaar abica L. and Casuarina equisetifolia L. are traditionally used in folk medicine for the treatment of a variety of common ailments like nausea, cold, cough, [...] Read more.

Different parts of Acacia nilotica (L.) Delile, Calotropis procera (Aiton) W.T. Aiton, Adhatoda vasica Nees, Fagoniaar abica L. and Casuarina equisetifolia L. are traditionally used in folk medicine for the treatment of a variety of common ailments like nausea, cold, cough, asthma, fevers, diarrhea, sore throat, swelling, etc. The present study was aimed to evaluate the anti-Helicobacter pylori and urease inhibition activities of extracts produced from the above selected medicinal plants native to Soon Valley (home to an old civilization) in the Punjab province of Pakistan. Methanol, acetone and water extracts of the plants were evaluated for anti-bacterial activity against thirty four clinical isolates and two reference strains of H. pylori. Minimum inhibitory concentrations (MICs) of the extracts were determined using the agar dilution method and compared with some standard antibiotics like amoxicillin (AMX), clarithromycin (CLA), tetracycline (TET) and metronidazole (MNZ), used in the triple therapy for H. pylori eradication. H. pylori urease inhibition activity of the extracts was assessed by the phenol red method, wherein, Lineweaver-Burk plots were used to determine Michaelis-Menten constants for elucidating the mechanism of inhibition. Methanol and acetone extracts from Acacia nilotica and Calotropis procera exhibited stronger anti-H. pylori activity than MNZ, almost comparable activity with TET, but were found to be less potent than AMX and CLT. The rest of the extracts exhibited lower activity than the standard antibiotics used in this study. In the H. pylori urease inhibitory assay, methanol and acetone extracts of Acacia nilotica and Calotropis procera showed significant inhibition. Lineweaver-Burk plots indicated a competitive mechanism for extract of Acacia nilotica, whereas extract of Calotropis procera exhibited a mixed type of inhibition. Full article

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Open AccessArticle

PF2401-SF, Standardized Fraction of Salvia miltiorrhiza, Induces Apoptosis of Activated Hepatic Stellate Cells in Vitro and in Vivo

by Daya Ram Parajuli, Eun-Jeon Park, Xian-Hua Che, Wen-Yi Jiang, Youn-Chul Kim, Dong Hwan Sohn and Sung Hee Lee

Molecules 2013, 18(2), 2122-2134; https://doi.org/10.3390/molecules18022122 - 6 Feb 2013

Cited by 13 | Viewed by 5138

Abstract

During the course of our attempts to develop a potential herbal medicine, we had previously prepared PF2401-SF, a standardized fraction of S. miltiorrhiza, and reported its hepatoprotective activity in vitro as well as in vivo. Since apoptosis of activated hepatic stellate [...] Read more.

During the course of our attempts to develop a potential herbal medicine, we had previously prepared PF2401-SF, a standardized fraction of S. miltiorrhiza, and reported its hepatoprotective activity in vitro as well as in vivo. Since apoptosis of activated hepatic stellate cells (HSCs) is a well-accepted anti-fibrotic strategy, in this study, we investigated the direct effect of PF2401-SF on t-HSC/Cl-6 cells in vitro and on CCl₄-induced liver injury in vivo. We evaluated the activation and cleavage of hallmarkers of apoptosis, namely, caspase 3, 8, 9 and PARP. Upregulation of the pro-apoptotic Bax protein and downregulation of the anti-apoptotic Bcl2 protein were also analyzed. Furthermore, in the PF2401-SF treated rats, apoptosis induction of activated HSCs was demonstrated by reduced distribution of α-SMA-positive cells and the presence of high number of TUNEL-positive cells in vivo. Our data suggest that PF2401-SF can mediate HSCs apoptosis induction, and may be a potential herbal medicine for the treatment of liver fibrosis. Full article

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Open AccessArticle

Simultaneous Determination of Multiple Sesquiterpenes in Curcuma wenyujin Herbal Medicines and Related Products with One Single Reference Standard

by Jing-Jing Zhu, Yue-Wei An, Guang Hu, Guo-Ping Yin, Qi-Wei Zhang and Zhi-Min Wang

Molecules 2013, 18(2), 2110-2121; https://doi.org/10.3390/molecules18022110 - 6 Feb 2013

Cited by 27 | Viewed by 5585

Abstract

Some Curcuma species are widely used as herbal medicines. Sesquiterpenes are their important bioactive compounds and their quantitative analysis is generally accomplished by gas chromatography (GC) or high performance liquid chromatography (HPLC), but the instability and high cost of some sesquiterpene reference standards [...] Read more.

Some Curcuma species are widely used as herbal medicines. Sesquiterpenes are their important bioactive compounds and their quantitative analysis is generally accomplished by gas chromatography (GC) or high performance liquid chromatography (HPLC), but the instability and high cost of some sesquiterpene reference standards have limited their application. It is necessary to find a practicable means to control the quality of herbal medicines. Using one stable component contained in Curcuma species to determine multiple analogues should be a practical option. In this study, a simple HPLC method for determination of sesquiterpenes using relative response factors (RRFs) has been developed. The easily available and stable active component curdione was selected as the reference compound for calculating the RRFs of the other eight sesquiterpenes, including zedoarondiol (Zedo), isozedoarondiol (Isoz), aerugidiol (Aeru), (4S,5S)-(+)-germacrone-4,5-epoxide (Epox), curcumenone (Curc), neocurdione (Neoc), germacrone (Germ) and furanodiene (Fura). Their RRFs against curdione were between 0.131–1.301, with a good reproducibility. By using the RRFs, the quantification of sesquiterpenes in Curcuma wenyujin herbal medicines and related products was carried out. The method is especially useful for the determination of (4S,5S)-(+)-germacrone-4,5-epoxide, curcumenone, germacrone and furanodiene, which often are regarded as the principle components in Curcuma species, but unstable when were purified. It is an ideal means to analyze the components for which reference standards are not readily available. Full article

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Open AccessArticle

Palladium-Catalyzed Amination of Dichloroquinolines with Adamantane-Containing Amines

by Anton S. Abel, Alexei D. Averin, Olga A. Maloshitskaya, Evgenii N. Savelyev, Boris S. Orlinson, Ivan A. Novakov and Irina P. Beletskaya

Molecules 2013, 18(2), 2096-2109; https://doi.org/10.3390/molecules18022096 - 6 Feb 2013

Cited by 10 | Viewed by 5646

Abstract

Pd-catalyzed amination of isomeric 2,6-, 2,8-, 4,8- and 4,7-dichloroquinolines was studied using adamantane-containing amines in which substituents at the nitrogen atom differ in bulkiness. The selectivity of the amination of 2,6-dichloroquinoline was very low, substantially better results were obtained with 2,8-dichloroquinoline, and 4,8- [...] Read more.

Pd-catalyzed amination of isomeric 2,6-, 2,8-, 4,8- and 4,7-dichloroquinolines was studied using adamantane-containing amines in which substituents at the nitrogen atom differ in bulkiness. The selectivity of the amination of 2,6-dichloroquinoline was very low, substantially better results were obtained with 2,8-dichloroquinoline, and 4,8- and 4,7-dichloroquinolines provided the best yields of the amination products. Diamination of 4,8- and 4,7-dichloroquinolines was carried out with two amines which differ strongly in the bulkiness of the alkyl group. In the majority of cases BINAP ligand was successfully applied, however, it had to be replaced with DavePhos in certain reactions when using the most sterically hindered amine as well as for the diamination reactions. Full article

(This article belongs to the Special Issue Advances in Heteroaromatic Chemistry)

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223 KiB

Open AccessArticle

The Reaction of Ethyl 2-oxo-2H-chromene-3-carboxylate with Hydrazine Hydrate

by Hatem A. Abdel-Aziz, Tilal Elsaman, Mohamed I. Attia and Amer M. Alanazi

Molecules 2013, 18(2), 2084-2095; https://doi.org/10.3390/molecules18022084 - 6 Feb 2013

Cited by 17 | Viewed by 14945

Abstract

Although salicylaldehyde azine (3) was reported in 1985 as the single product of the reaction of ethyl 2-oxo-2H-chromene-3-carboxylate (1) with hydrazine hydrate, we identified another main reaction product, besides 3, which was identified as malono-hydrazide ( [...] Read more.

Although salicylaldehyde azine (3) was reported in 1985 as the single product of the reaction of ethyl 2-oxo-2H-chromene-3-carboxylate (1) with hydrazine hydrate, we identified another main reaction product, besides 3, which was identified as malono-hydrazide (4). In the last two decades, however, some articles have claimed that this reaction afforded exclusively hydrazide 2 and they have reported the use of this hydrazide 2 as a precursor in the syntheses of several heterocyclic compounds and hydrazones 6. We reported herein a study of the formation of 2 and a facile route for the synthesis of the target compounds N'-arylidene-2-oxo-2H-chromene-3-carbohydrazides 6a–f. Full article

(This article belongs to the Section Organic Chemistry)

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116 KiB

Open AccessEditorial

Molecules Best Paper Award 2013

by Derek J. McPhee

Molecules 2013, 18(2), 2081-2083; https://doi.org/10.3390/molecules18022081 - 5 Feb 2013

Viewed by 5634

Abstract

Molecules has started to institute a "Best Paper" award to recognize the most outstanding papers in the area of natural products, medicinal chemistry and molecular diversity published in Molecules. We are pleased to announce the second "Molecules Best Paper Award" for [...] Read more.

Molecules has started to institute a "Best Paper" award to recognize the most outstanding papers in the area of natural products, medicinal chemistry and molecular diversity published in Molecules. We are pleased to announce the second "Molecules Best Paper Award" for 2013. Candidates were chosen by the Editor-in-Chief and selected editorial board members from among all the papers published in 2009. [...] Full article

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Open AccessArticle

Antioxidant Capacity and HPLC-DAD-MS Profiling of Chilean Peumo (Cryptocarya alba) Fruits and Comparison with German Peumo (Crataegus monogyna) from Southern Chile

by Mario J. Simirgiotis

Molecules 2013, 18(2), 2061-2080; https://doi.org/10.3390/molecules18022061 - 5 Feb 2013

Cited by 99 | Viewed by 8457

Abstract

Liquid chromatography (LC) coupled with UV detection and electrospray ionization (ESI) tandem mass spectrometry (MS/MS) was used for the generation of chemical fingerprints and the identification of phenolic compounds in peumo fruits and aerial parts from southern Chile. Thirty three compounds (19 of [...] Read more.

Liquid chromatography (LC) coupled with UV detection and electrospray ionization (ESI) tandem mass spectrometry (MS/MS) was used for the generation of chemical fingerprints and the identification of phenolic compounds in peumo fruits and aerial parts from southern Chile. Thirty three compounds (19 of these detected in C. alba and 23 in C. monogyna) were identified, mainly flavonoid glycosides, phenolic acids, anthocyanins and flavonoid aglycons. Total phenolic content and total flavonoid content was measured for both species, and were higher in the extracts from C. monogyna fruits and aerial parts than extracts from C. alba. The fruits of Cryptocarya alba (Chilean peumo) presented high antioxidant capacity (9.12 ± 0.01 mg/mL in the DPPH assay), but was three times lower to that of Crataegus monogyna (German peumo) (3.61 ± 0.01 mg/mL in the DPPH assay). Full article

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Open AccessArticle

Evaluation of the Anti-Inflammatory Effect of Chalcone and Chalcone Analogues in a Zebrafish Model

by Yau-Hung Chen, Wei-Hua Wang, Yun-Hsin Wang, Zi-Yu Lin, Chi-Chung Wen and Ching-Yuh Chern

Molecules 2013, 18(2), 2052-2060; https://doi.org/10.3390/molecules18022052 - 5 Feb 2013

Cited by 46 | Viewed by 6932

Abstract

The aim of this study was to investigate novel chalcones with potent anti-inflammatory activities in vivo. Chalcone and two chalcone analogues (compound 5 and 9) were evaluated using a caudal fin-wounded transgenic zebrafish line “Tg(mpx:gfp)” to visualize [...] Read more.

The aim of this study was to investigate novel chalcones with potent anti-inflammatory activities in vivo. Chalcone and two chalcone analogues (compound 5 and 9) were evaluated using a caudal fin-wounded transgenic zebrafish line “Tg(mpx:gfp)” to visualize the effect of neutrophil recruitment dynamically. Results showed that treatment with compound 9 not only affected wound-induced neutrophil recruitment, but also affected Mpx enzymatic activity. Moreover, protein expression levels of pro-inflammatory factors (Mpx, NFκB, and TNFα) were also regulated by compound 9. Taken together, our results provide in vivo evidence of the anti-inflammatory effects of synthesized chalcone analogues on wound-induced inflammation. Full article

(This article belongs to the Section Medicinal Chemistry)

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1073 KiB

Open AccessArticle

Structural Requirements for the Antifungal Activities of Natural Drimane Sesquiterpenes and Analogues, Supported by Conformational and Electronic Studies

by Marcos Derita, Iván Montenegro, Francisco Garibotto, Ricardo D. Enriz, Mauricio Cuellar Fritis and Susana A. Zacchino

Molecules 2013, 18(2), 2029-2051; https://doi.org/10.3390/molecules18022029 - 5 Feb 2013

Cited by 30 | Viewed by 5592

Abstract

Seventeen drimanes including polygodial (1), isopolygodial (2), drimenol (3) and confertifolin (4) obtained from natural sources and the semi-synthetic derivatives 5–17 obtained from 1–3, were evaluated in vitro for antifungal properties against a unique [...] Read more.

Seventeen drimanes including polygodial (1), isopolygodial (2), drimenol (3) and confertifolin (4) obtained from natural sources and the semi-synthetic derivatives 5–17 obtained from 1–3, were evaluated in vitro for antifungal properties against a unique panel of fungi with standardized procedures by using two end-points, MIC₁₀₀ and MIC₅₀. A SAR analysis of the whole series, supported by conformational and electronic studies, allowed us to show that the Δ^7,8 -double bond would be one of the key structural features related to the antifungal activity. The MEPs obtained for active compounds exhibit a clear negative minimum value (deep red zone) in the vicinity of the Δ^7,8-double bond, which is not present in the inactive ones. Apart of this negative zone, a positive region (deep blue) appears in 1, which is not observed either in its epimer 2 nor in the rest of the active compounds. The LogP of active compounds varies between 2.33 and 3.84, but differences in MICs are not correlated with concomitant variations in LogP values. Full article

(This article belongs to the Section Natural Products Chemistry)

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1465 KiB

Open AccessArticle

The Degradation Mechanism of Toxic Atractyloside in Herbal Medicines by Decoction

by Liang-Yu Chen, Anren Hu and Chih-Jui Chang

Molecules 2013, 18(2), 2018-2028; https://doi.org/10.3390/molecules18022018 - 5 Feb 2013

Cited by 14 | Viewed by 5784

Abstract

Atractyloside (ATR) is found in many Asteraceae plants that are commonly used as medicinal herbs in China and other eastern Asian countries. ATR binds specifically to the adenine nucleotide translocator in the inner mitochondrial membrane and competitively inhibits ADP and ATP transport. The [...] Read more.

Atractyloside (ATR) is found in many Asteraceae plants that are commonly used as medicinal herbs in China and other eastern Asian countries. ATR binds specifically to the adenine nucleotide translocator in the inner mitochondrial membrane and competitively inhibits ADP and ATP transport. The toxicity of ATR in medical herbs can be reduced by hydrothermal processing, but the mechanisms of ATR degradation are not well understood. In this study, GC-MS coupled with SPE and TMS derivatisation was used to detect ATR levels in traditional Chinese medicinal herbs. Our results suggest that ATR molecules were disrupted by decomposition, hydrolysis and saponification after heating with water (decoction) for a long period of time. Hydrothermal processing could decompose the endogenous toxic compounds and also facilitate the detoxification of raw materials used in the Chinese medicine industry. Full article

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Molecules, Volume 18, Issue 2 (February 2013) – 81 articles , Pages 1337-2457

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