Phytochemical Analysis

Current research reports and chronological list of recent articles.

The international scientific journal Phytochemical Analysis is devoted to the publication of original articles concerning the development, improvement, validation and/or extension of application of analytical methodology in the plant sciences. The spectrum of coverage is broad, encompassing methods and techniques relevant to the detection (including bio-screening), extraction, separation, purification, identification and quantification of compounds in plant biochemistry, plant cellular and molecular biology, plant biotechnology, the food sciences, agriculture and horticulture

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Additional research articles see Current Chemistry Research Articles. Magazines with similar content (phytochemistry):

 - Phytochemistry.

 - Phytochemistry Letters.

 - Phytochemistry Reviews.

Phytochemical Analysis - Abstracts

A luminescence assay for natural product inhibitors of the Mycobacterium tuberculosis proteasome

Introduction Mycobacterium tuberculosis (Mtb) causes a large global burden of disease, with a high mortality rate in healthy and immuno-compromised patients. A number of molecular targets have been identified for treatment of this disease, including the Mtb proteasome. The Mtb proteasome enhances Mtb survival during nitrosative and oxidative stress in the latent, non-replicative phase. Therefore, Mtb proteasome inhibition could help to combat Mtb infections that do not respond to current therapies. Objective To develop and validate a novel biochemical assay to assess Mtb proteasome activity in the presence of organic and aqueous plant test extracts. Method Fluorescence (photoluminescence) and luminescence (chemiluminescence) assays were investigated as potential methods to determine the robustness and repeatability for use in screening natural product extracts for Mtb proteasome inhibitors. Results The fluorescence assay, used widely for Mtb proteasome activity assays, was subject to interference due to the natural fluorescence of compounds in many of the extracts; there is little interference with the luminescence approach. As proof of principle, we used the luminescence assay to screen a small set of plant test extracts. Conclusions Luminescence is the more suitable assay for assay of plant natural product extracts. The sensitivities of the luminescence and fluorescence assays are comparable. A Z′-factor of 0.58 for the luminescence assay makes it suitable for medium-to-high throughput screening efforts. Copyright © 2016 John Wiley & Sons, Ltd.
Datum: 18.01.2016

Application of diffusion-edited and solvent suppression 1H-NMR to the direct analysis of markers in valerian-hop liquid herbal products

Introduction – The rising trend to consume herbal products for the treatment and/or prevention of minor ailments together with their chemical and pharmacological complexity means there is an urgent need to develop new approaches to their quality and stability. Objectives – This work looks at the application of one-dimensional diffusion-edited 1H-NMR spectroscopy (1D DOSY) and 1H-NMR with suppression of the ethanol and water signals to the characterisation of quality and stability markers in multi-component herbal medicines/food supplements. Material and Methods – The experiments were performed with commercial tinctures of Valeriana officinalis L. (valerian), expired and non-expired, as well as its combination with Hummulus lupulus L. (hops), which is one of the most popular blends of relaxant herbs. These techniques did not require purification or evaporation of components for the qualitative analysis of the mixture, but only the addition of D2O and TSP. Results – The best diagnostic signals were found at δ 7 ppm (H-11, valerenic acid), δ 4.2 ppm (H-1, hydroxyvalerenic acid) and δ 1.5-1.8 ppm (methyl groups in prenylated moieties, α-acids/prenylated flavones). Conclusion – This work concludes on the potential value of 1D DOSY 1H-NMR to provide additional assurance of quality in complex natural mixtures. Copyright © 2016 John Wiley & Sons, Ltd.
Datum: 13.01.2016

Flavonoids from the flowers of Impatiens glandulifera Royle isolated by high performance countercurrent chromatography

Introduction Impatiens glandulifera Royle (Balsaminaceae) is an annual herb from the Himalaya region, currently widespread along European river systems and one of the most important neophyte invading plants in Germany. Exploring the effects of allelopathic plant chemicals is important for the understanding of its ecological impacts in the process of suppression of indigenous plant species. Objective To investigate the chemical composition of Impatiens glandulifera flowers (IGFs) using high performance countercurrent chromatography (HPCCC). Methods The flowers of Impatiens glandulifera were manually separated and extracted with ethanol. LC-ESI-MS/MS was used to characterise the crude extract of IGF. The various flavonoids detected were isolated by HPCCC using of methyl tert-butyl ether–acetonitrile–water (2:2:3, v/v/v). The combination of the data provided by preparative ESI-MS/MS metabolite profiling, LC-ESI-MS/MS, UV-vis and 1D/2D-NMR spectroscopic analysis was used to elucidate the structures of the isolated compounds. Results HPCCC runs led to the direct isolation of pure dihydromyricetin (ampelopsin), eriodictyol-7-O-glucoside, kaempferol-3-O-glucoside (astragalin) and kaempferol-3-O-6ʺ-malonyl-glucoside, as well as the pre-purification of kaempferol-3-O-rhamno-rhamnosyldiglucoside, quercetin-3-O-galactoside (hyperoside), quercetin and kaempferol in a single step. Conclusion This is the first report on the flavonoid composition of the species Impatiens glandulifera. The developed protocol was successfully used to isolate the main flavonoids from the crude extract of IGFs. This combined HPCCC and HPLC procedure could be applied to the fast fractionation and recovery of flavonoid derivatives of other plant extracts. Copyright © 2016 John Wiley & Sons, Ltd.
Datum: 11.01.2016

Chemical characterisation of Nigerian red propolis and its biological activity against Trypanosoma Brucei

Introduction A previous study showed the unique character of Nigerian red propolis from Rivers State, Nigeria (RSN), with regards to chemical composition and activity against Trypanosoma brucei in comparison with other African propolis. Objective To carry out fractionation and biological testing of Nigerian propolis in order to isolate compounds with anti-trypanosomal activity. To compare the composition of the RSN propolis with the composition of Brazilian red propolis. Methodology Profiling was carried out using HPLC-UV-ELSD and HPLC-Orbitrap-FTMS on extracts of two samples collected from RSN with data extraction using MZmine software. Isolation was carried out by normal phase and reversed phase MPLC. Elucidation of the compounds with a purity > 95% was performed by 1D/2D NMR HRMS and HRLC-MSn. Results Ten phenolic compounds were isolated or in the case of liquiritigenin partially purified. Data for nine of these correlated with literature reports of known compounds i.e. one isoflavanone, calycosin (1); two flavanones, liquiritigenin (2) and pinocembrin (5); an isoflavan, vestitol (3); a pterocarpan, medicarpin (4); two prenylflavanones, 8-prenylnaringenin (7) and 6-prenylnaringenin (8); and two geranyl flavonoids, propolin D (9) and macarangin (10). The tenth was elucidated as a previously undescribed dihydrobenzofuran (6). The isolated compounds were tested against Trypanosoma brucei and displayed moderate to high activity. Some of the compounds tested had similar activity against wild type T. brucei and two strains displaying pentamidine resistance. Conclusion Nigerian propolis from RSN has some similarities with Brazilian red propolis. The propolis displayed anti-trypanosomal activity at a potentially useful level. Copyright © 2015 John Wiley & Sons, Ltd.
Datum: 11.12.2015

Preparation and application of a monoclonal antibody against the isoflavone glycoside daidzin using a mannich reaction-derived hapten conjugate

Introduction Daidzin and its aglycone daidzein are major pharmacologically active compounds of soybean (Glycine max), kudzu (Pueraria lobata), and kwao kruea khao (P. mirifica). Pharmacological activities of daidzin are mediated by its more potent metabolites daidzein and equol; however, daidzin is the predominant compound found in these medicinal plants, and the efficacy and safety of equol depend on the amount of daidzin consumed. Objective To develop a specific monoclonal antibody (MAb)-based indirect competitive enzyme-linked immunosorbent assay (icELISA) for standardisation of daidzin content in herbal medicines or nutraceuticals. Methodology The Mannich reaction was used for the synthesis of a highly immunogenic conjugate between daidzin and a cationised carrier protein. Splenocytes of hyperimmunised mice were fused with myeloma cells to generate a hybridoma secreting antibody against daidzin. Results The icELISA showed high selectivity and acceptable sensitivity for daidzin determination (1.56–100 ng/mL) with high reproducibility (coefficients of variation were < 5%). The icELISA was a reliable analytical method for daidzin in Glycine max, Pueraria lobata and P. mirifica, for which daidzin recoveries from spiked samples were 98.99–104.94%. Daidzin content of these plant-derived products determined using the icELISA were in close agreement with those determined by a HPLC-UV method. Conclusion The icELISA is useful for specific daidzin determination because of its reliability, low cost, speed and high throughput. Copyright © 2015 John Wiley & Sons, Ltd.
Datum: 07.12.2015


No abstract is available for this article.
Datum: 07.12.2015

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No abstract is available for this article.
Datum: 07.12.2015

Analysis of phytochemical variations in dioecious Tinospora cordifolia stems using HPLC/QTOF MS/MS and UPLC/QqQLIT-MS/MS

Introduction The stem of dioecious Tinospora cordifolia (Menispermaceae) is a commonly used traditional Ayurvedic medicine in India having several therapeutic properties. Objective To develop and validate LC-MS methods for the identification and simultaneous quantitation of various secondary metabolites and to study metabolomic variations in the stem of male and female plants. Methods Ethanolic extract of stems were analysed by HPLC/ESI-QTOF-MS/MS for rapid screening of bioactive phytochemicals. High resolution MS and MS/MS in positive ESI mode were used for structural investigation of secondary metabolites. An UPLC/ESI-QqQLIT-MS/MS method in MRM mode was developed and validated for the simultaneous quantitation of five bioactive alkaloids. Results Identification and characterisation of 36 metabolites including alkaloids, sesquiterpenes and phytoecdysteroids were performed using LC-MS and MS/MS techniques. The bioactive alkaloids such as jatrorrhizine, magnoflorine, isocorydine, palmatine and tetrahydropalmatine were successfully quantified in male and female plants. The mean abundances of magnoflorine jatrorrhizine, and oblongine were significantly (P < 0.05) higher in male plants while mean abundances of tetrahydropalmatine, norcoclaurine, and reticuline were significantly (P < 0.05) higher in female plants. Conclusions Phytochemicals in the stem of male and female Tinospora cordifolia showed significant qualitative and quantitative variations. LC-MS and MS/MS methods can be used to differentiate between male and female plants based on their chemical profiles and quantities of the marker bioactive alkaloids. This chemical composition difference was also evident during vegetative stage when there were no male and female flowers. Copyright © 2015 John Wiley & Sons, Ltd.
Datum: 02.12.2015

Application of NIR and MIR spectroscopy for rapid determination of antioxidant activity of Radix Scutellariae from different geographical regions

Introduction The beneficial health effects of traditional Chinese medicines are often attributed to their potent antioxidant activities, usually established in vitro. However, these wet chemical methods for determining antioxidant activities are time-consuming, laborious, and expensive. Objectives This study was conducted to establish a rapid determination of antioxidant activity of Radix Scutellariae using near-infrared (NIR) and mid-infrared (MIR) spectroscopy. Material and methods Antioxidant capabilities were evaluated using 2,2-diphenyl-1-picrylhydrazyl hydrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) assays. The total flavonoid contents (TFCs) of Radix Scutellariae were measured by the aluminium chloride colorimetric method. The same sample was then scanned using NIR and MIR spectroscopy. Chemometrics analysis using partial least-squares (PLS) regression was performed to establish the models for predicting the antioxidant activities of Radix Scutellariae. Results A better predictive performance was achieved using PLS models based on NIR data. The determination coefficient (R2) and the residual predictive deviation (RPD) for the validation set were 0.9298 and 2.84 for DPPH, and 0.9436 and 2.66 for TFCs, respectively. MIR-PLS algorithms gave a slightly lower reliability (R2 = 0.9090 and 0.9374, RPD = 2.01 and 2.42, for DPPH and TFC, respectively). Very comparable results for ORAC were obtained with the two methods. Conclusion The developed spectroscopic method can be successfully applied in high-throughput screening of the antioxidant capability of Radix Scutellariae samples. It can also be a viable and advantageous alternative to laborious chemical procedures. Copyright © 2015 John Wiley & Sons, Ltd.
Datum: 19.11.2015

Screening of peroxynitrite scavengers in Flos Lonicerae by using two new methods, an HPLC-DAD-CL technique and a peroxynitrite spiking test followed by HPLC-DAD analysis

Introduction Peroxynitrite is involved in the pathogenesis of a number of significant diseases. Peroxynitrite scavengers thus have potential application in understanding and treating these diseases. It is, therefore, important to establish screening methods able to rapidly identify peroxynitrite scavengers from herbal plants. Objective To develop effective and easily operable screening methods for identifying peroxynitrite scavengers in complex matrices, including Chinese herbal medicines. Methods Two simple and efficient screening methods have been developed for the identification of natural peroxynitrite scavengers in Flos Lonicerae Japonicae (FLJ). Method I used HPLC-DAD-(luminol-peroxynitrite)-CL techniques combined with Q-TOF MS/MS analysis, while Method II used pre-column reaction of the sample with peroxynitrite, followed by HPLC separation and Q-TOF MS/MS analysis. Results Five peroxynitrite scavengers (neochlorogenic acid, chlorogenic acid, 3,4-O-dicaffeoyl quinic acid, 3,5-O-dicaffeoyl quinic acid and 4,5-O-dicaffeoyl quinic acid) were identified in FLJ using Method I. Besides the compounds identified using Method I, three additional peroxynitrite scavengers (rutin, isoquercitrin and luteoloside) were identified using Method II. Conclusion The two new methods proved to be complementary and the use of these methods should allow rapid detection of peroxynitrite-scavenging natural products from FLJ and other complex matrices. Copyright © 2015 John Wiley & Sons, Ltd.
Datum: 16.11.2015

Application of comprehensive NMR-based analysis strategy in annotation, isolation and structure elucidation of low molecular weight metabolites of Ricinus communis seeds

Introduction Powder-like extract of Ricinus communis seeds contain a toxic protein, ricin, which has a history of military, criminal and terroristic use. As the detection of ricin in this “terrorist powder” is difficult and time-consuming, related low mass metabolites have been suggested to be useful for screening as biomarkers of ricin. Objective To apply a comprehensive NMR-based analysis strategy for annotation, isolation and structure elucidation of low molecular weight plant metabolites of Ricinus communis seeds. Methodology The seed extract was prepared with a well-known acetone extraction approach. The common metabolites were annotated from seed extract dissolved in acidic solution using 1H NMR spectroscopy with spectrum library comparison and standard addition, whereas unconfirmed metabolites were identified using multi-step off-line HPLC-DAD-NMR approach. Results In addition to the common plant metabolites, two previously unreported compounds, 1,3-digalactoinositol and ricinyl-alanine, were identified with support of MS analyses. Conclusion The applied comprehensive NMR-based analysis strategy provided identification of the prominent low molecular weight metabolites with high confidence. Copyright © 2015 John Wiley & Sons, Ltd.
Datum: 14.10.2015

Simultaneous Detection of Flavonoids, Phenolic Acids and Alkaloids in Abri Herba and Abri Mollis Herba using Liquid Chromatography Tandem Mass Spectrometry

Introduction Abri Herba has remarkable properties, such as cleanup heat detoxification, dampness and activating blood circulation to dissipate blood stasis; as a result, it has been applied to treat acute or chronic hepatitis and mastitis. Abri mollis Herba is often used as Abri Herba. Hierarchical cluster analysis (HCA) was applied to compare the similarities and differences of the chemical compositions in the two types of medicinal materials. Objective To establish a high-performance liquid chromatography and tandem mass spectrometry (HPLC–MS/MS) method for the simultaneous analysis of 15 flavonoids, two phenolic acids and three alkaloids in Abri Herba and Abri mollis Herba. Methodology The chromatographic separation was performed on a C18 column with a mobile phase of methanol (A), acetonitrile (B) and 0.5‰ acetic acid in water (C) using gradient elution. The detection of the target compounds was performed in multiple-reaction monitoring (MRM) mode using a hybrid quadrupole linear ion trap mass spectrometer equipped with positive/negative ion-switching electrospray ionisation (ESI) source. Results The developed method is reliable, sensitive and specific. In addition, the method has been successfully applied to differentiate 15 batches of Abri Herba and 27 batches of Abri mollis Herba stems. Furthermore, a comparison of the contents among stems, roots and leaves from the same strain in seven batches of Abri mollis Herba and four batches of Abri Herba has also been performed. Conclusion HPLC–MS/MS method is sensitive and selective and can be suitable for the reliable quality control of Abri mollis Herba and Abri Herba. Copyright © 2015 John Wiley & Sons, Ltd.
Datum: 28.09.2015

Analytical Profiling of Bioactive Phenolic Compounds in Argan (Argania spinosa) Leaves by Combined Microextraction by Packed Sorbent (MEPS) and LC-DAD-MS/MS

Introduction The argan tree (Argania spinosa) is an endemic species from south-western Morocco. Argan-based preparations have been widely used in Moroccan traditional medicine for their biological properties, as well as for several cosmetic purposes. Whereas kernel, pulp of fruit and trunk have been extensively studied for their nutritional and pharmacological effects, relatively little is known about argan tree leaves. Objective The main purpose of the present study is to investigate and characterise the bioactive phenolic fractions in both crude and aqueous extracts derived from argan tree leaves. Methodology A qualitative profile of the antioxidant phenolic compounds in argan leaves was obtained by means of structural hypothesis based on UV spectra and mass spectrometric fragmentation patterns. Moreover, selected phenolics were quantified in argan leaves by using a fully validated method based on liquid chromatography coupled to diode array detection and tandem mass spectrometry (LC-DAD-MS/MS). All the extracts were purified by a fast and reliable microextraction by packed sorbent (MEPS) procedure, before analysing them by LC-MS/MS. Results Based on retention times, mass spectrometric fragmentation and UV spectra, 13 phenolic compounds were identified or tentatively elucidated from crude and aqueous extracts derived from Argania spinosa leaves, while seven compounds were quantified in both extracts. Conclusion The obtained results could represent a first step towards a complete characterisation of the argan plant, its bioactive profiling and the valorisation of its by-products as a source of potentially beneficial bioactive molecules. Copyright © 2015 John Wiley & Sons, Ltd.
Datum: 09.09.2015

Quantitation of phenylpropanoids and iridoids in insulin-sensitising extracts of Leonurus sibiricus L. (Lamiaceae)

Introduction Leonurus sibiricus L. is regularly used in traditional Mongolian medicine including for the treatment of symptoms of diabetes mellitus. Objectives To provide a validated quantitation method for the quality control of Leonurus sibiricus and to prove in vitro insulin-sensitisation, thereby supporting the traditional use of Leonurus sibiricus. Methodology Pulverised Leonurus sibiricus material was either extracted with methanol or methanol:water (25:75, v/v). HPLC-CAD (charged aerosol detector) separations were performed on a Luna Phenyl-Hexyl column with water and acetonitrile (both modified with 0.1% formic acid) as mobile phase. Gradient elution was employed using theophylline as internal standard. Tentative peak identification was facilitated by HPLC-MS. Validation was carried out according to ICH (International Conference on Harmonisation) guidelines. Potential insulin-sensitisation of accordant extracts was assessed in glucose uptake experiments in C2C12 myocytes and protein tyrosine phosphatase 1B (PTP1B) enzyme assays. Results Thirty-six compounds were tentatively identified based on their retention times, UV spectra, MS fragments and data from literature. They comprise phenolcarboxylic acids, flavonoids, iridoid glycosides, and phenylpropanoids, among which acetylharpagide, ajugoside, lavandulifolioside, and verbascoside were selected for quantitation. The methanol extract contained 0.42% combined iridoids, and 1.58% combined phenylpropanoids. Validation showed good accuracy, intermediate precision and robustness. The methanol extract of Leonurus sibiricus led to a 1.5 fold increase in insulin-stimulated cellular glucose uptake and inhibition of PTP1B by 40% at a concentration of 10 µg/mL. Conclusion HPLC-CAD analysis allowed sensitive quantitation of the selected marker compounds in Leonurus sibiricus, thereby providing a reliable tool for its quality control. Copyright © 2015 John Wiley & Sons, Ltd.
Datum: 02.09.2015

Use of time-resolved spectroscopy as a method to monitor carotenoids present in tomato extract obtained using ultrasound treatment

Introduction Compounds exhibiting antioxidant activity have received much interest in the food industry because of their potential health benefits. Carotenoids such as lycopene, which in the human diet mainly derives from tomatoes (Solanum lycopersicum), have attracted much attention in this aspect and the study of their extraction, processing and storage procedures is of importance. Optical techniques potentially offer advantageous non-invasive and specific methods to monitor them. Objectives To obtain both fluorescence and Raman information to ascertain if ultrasound assisted extraction from tomato pulp has a detrimental effect on lycopene. Method Use of time-resolved fluorescence spectroscopy to monitor carotenoids in a hexane extract obtained from tomato pulp with application of ultrasound treatment (583 kHz). The resultant spectra were a combination of scattering and fluorescence. Because of their different timescales, decay associated spectra could be used to separate fluorescence and Raman information. This simultaneous acquisition of two complementary techniques was coupled with a very high time-resolution fluorescence lifetime measurement of the lycopene. Results Spectroscopic data showed the presence of phytofluene and chlorophyll in addition to lycopene in the tomato extract. The time-resolved spectral measurement containing both fluorescence and Raman data, coupled with high resolution time-resolved measurements, where a lifetime of ~5 ps was attributed to lycopene, indicated lycopene appeared unaltered by ultrasound treatment. Detrimental changes were, however, observed in both chlorophyll and phytofluene contributions. Conclusion Extracted lycopene appeared unaffected by ultrasound treatment, while other constituents (chlorophyll and phytofluene) were degraded. Copyright © 2015 John Wiley & Sons, Ltd.
Datum: 20.08.2015

Multi-response optimisation of ultrasound-assisted extraction for recovery of flavonoids from red grape skins using response surface methodology

Introduction For the characterisation of grape cultivars, the profile and content of flavonoids are important because these compounds impact grape and wine quality. To determine the correct profile and content of flavonoids, the use of robust, sensitive and reliable methods is necessary. Objective The object of this research is to develop a new ultrasound-assisted extraction (UAE) method for the recovery of flavonoids from grape skins using response surface methodology. Method Optimisation of UAE was performed using a complementary study combining a Box-Behnken experimental design with qualitative analysis by high-performance liquid chromatography. Results Optimal extraction conditions were obtained using the extraction solvent composed of acetonitrile:water:formic acid (26:73:1, v/v/v) at an extraction temperature of 50°C, an extraction time of 15 min in a single-extraction step and with a solid-to-solvent ratio of 1:80 g/mL. The calculated relative standard deviations for the optimal extraction method were very low, measuring less than 5%. Conclusions This study demonstrates that numerous factors have strong effects on the extraction efficiency, including the type of organic modifier and its percentage in the extraction solvent, the number of extraction steps, the solid-to-solvent ratio, the extraction time and temperature and, finally, the particular nature of analyte and their position within the grape skin cell. Copyright © 2015 John Wiley & Sons, Ltd.
Datum: 06.08.2015

A new TLC bioautographic assay for qualitative and quantitative estimation of lipase inhibitors

Introduction Lipase inhibitory assays based on TLC bioautography have made recent progress; however, an assay with greater substrate specificity and quantitative capabilities would advance the efficacy of this particular bioassay. Objective To address these limitations, a new TLC bioautographic assay for detecting lipase inhibitors was developed and validated in this study. Methods The new TLC bioautographic assay was based on reaction of lipase with β-naphthyl myristate and the subsequent formation of the purple dye between β-naphthol and Fast Blue B salt (FBB). The relative lipase inhibitory capacity (RLIC) was determined by a TLC densitometry with fluorescence detection, expressed as orlistat equivalents in millimoles on a per sample weight basis. Six pure compounds and three natural extracts were evaluated for their potential lipase inhibitory activities by this TLC bioautographic assay. Results The β-naphthyl myristate as the substrate improved the detection sensitivity and specificity significantly. The limit of detection (LOD) of this assay was 0.01 ng for orlistat, the current treatment for obesity. This assay has acceptable accuracy (92.07–105.39%), intra-day and inter-day precisions [relative standard deviation (RSD), 2.64–4.40%], as well as intra-plate and inter-plate precisions (RSD, 1.8–4.9%). Conclusion The developed method is rapid, simple, stable, and specific for screening and estimation of the potential lipase inhibitors. Copyright © 2015 John Wiley & Sons, Ltd.
Datum: 29.07.2015

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