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1.
Plant Physiol ; 194(2): 1006-1023, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-37831417

RESUMO

Citronellol is a pleasant-smelling compound produced in rose (Rosa spp.) flowers and in the leaves of many aromatic plants, including pelargoniums (Pelargonium spp.). Although geraniol production has been well studied in several plants, citronellol biosynthesis has been documented only in crab-lipped spider orchid (Caladenia plicata) and its mechanism remains open to question in other species. We therefore profiled 10 pelargonium accessions using RNA sequencing and gas chromatography-MS analysis. Three enzymes from the progesterone 5ß-reductase and/or iridoid synthase-like enzymes (PRISE) family were characterized in vitroand subsequently identified as citral reductases (named PhCIRs). Transgenic RNAi lines supported a role for PhCIRs in the biosynthesis of citronellol as well as in the production of mint-scented terpenes. Despite their high amino acid sequence identity, the 3 enzymes showed contrasting stereoselectivity, either producing mainly (S)-citronellal or a racemate of both (R)- and (S)-citronellal. Using site-directed mutagenesis, we identified a single amino acid substitution as being primarily responsible for the enzyme's enantioselectivity. Phylogenetic analysis of pelargonium PRISEs revealed 3 clades and 7 groups of orthologs. PRISEs from different groups exhibited differential affinities toward substrates (citral and progesterone) and cofactors (NADH/NADPH), but most were able to reduce both substrates, prompting hypotheses regarding the evolutionary history of PhCIRs. Our results demonstrate that pelargoniums evolved citronellol biosynthesis independently through a 3-step pathway involving PRISE homologs and both citral and citronellal as intermediates. In addition, these enzymes control the enantiomeric ratio of citronellol thanks to small alterations of the catalytic site.


Assuntos
Monoterpenos Acíclicos , Aldeídos , Pelargonium , Pelargonium/química , Pelargonium/metabolismo , Progesterona , Filogenia , Oxirredutases/genética , Oxirredutases/metabolismo , Plantas/metabolismo
2.
Protoplasma ; 260(3): 853-868, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36329347

RESUMO

A greenhouse pot experiment was conducted to evaluate the impact of zinc supply (0, 1, and 2 mM Zn as ZnSO4) on morpho-physiological and biochemical parameters of caraway (Carum carvi L.). Exposure to different Zn concentrations for 12 weeks compromised severely all growth parameters (plant height, number of secondary branches, diameter of primary and secondary branches, fresh and dry weight of aerial parts and roots) yield and its components (number of umbels per primary branches and secondary branches; number of umbel per plant; number of seeds per plant; and the weight of 1000 seeds). These manifestations were intimately linked with excessive accumulation of Zn in roots and leaves, alteration of the content of photosynthetic pigments, and extended lipid peroxidation. A manifest increment of proline and soluble sugar content was also observed in response to Zn application. Lipid content in seeds was dropped in Zn-treated plants and the fatty acid profiles were profoundly affected as they were enriched with saturated fatty acids at the expense of unsaturated ones. While improving their oxidative stability as revealed by the reduced values calculated oxidizability and oxidative susceptibility, Zn treatment reduced the lipid nutritional quality of caraway seeds. Moreover, Zn treatment reduced the essential oil yield and its main component carvone while it enhanced the content of its precursor limonene. It also induced alteration of terpene metabolism as revealed in the redirection of the carbon flux to the shikimate/phenylpropanoid pathway resulting in the stimulation of the production of phenolic compounds and their subsequent antioxidant activities.


Assuntos
Carum , Óleos Voláteis , Zinco/farmacologia , Carum/química , Carum/metabolismo , Antioxidantes , Óleos Voláteis/química
3.
Talanta ; 252: 123801, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35969926

RESUMO

Natural plant extracts are primarily used as raw materials in the cosmetic and perfumery industry. However, adulterations with petrochemical products are occurring in the market, leading to non-100% natural products. Several analytical techniques such as impurity detection or enantioselective ratio assessments have been previously described as good indicators to detect any addition of synthetic products, but these techniques are ineffective with novel type of synthetic pathways such as semisynthesis. In order to improve authentication, development of advanced analytical strategies such as δ18O stable isotopic ratios assessment was tested on spearmint, cinnamon and bitter almond essential oils major metabolites (carvone, (E)-cinnamaldehyde, and benzaldehyde). Natural δ18O mean values (δ18OCarvone = 18.4‰; δ18OCinnamaldehyde = 13.9‰; δ18OBenzaldehyde = 16.5‰) were found to be higher than semisynthetic origin for the 3 studied molecules (δ18OCarvone = 9.2‰; δ18OCinnamaldehyde = 8.8‰; δ18OBenzaldehyde = 10.9‰). These measurements proved to be efficient to discriminate natural and semisynthetic origins of these components and therefore potentially lead to a novel way to authenticate natural products.


Assuntos
Produtos Biológicos , Mentha spicata , Óleos Voláteis , Prunus dulcis , Óleos Voláteis/química , Cinnamomum zeylanicum , Benzaldeídos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Isótopos , Isótopos de Carbono
4.
Talanta ; 247: 123550, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35671579

RESUMO

For the development of selective and sensitive chemical sensors, we have developed a new family of poly(ether-phosphoramide) polymers. These polymers were obtained with satisfactory yields by nucleophilic aromatic polycondensation using isosorbide as green resources, and bisphenol A with two novel difluoro phosphinothioic amide monomers. Unprecedented, the thiophosphorylated aminoheterocycles monomers, functionalized with two heterocyclic amine, N-methylpiperazine and morpholine were successfully obtained by nucleophilic substitution reaction of P(S)-Cl compound. The resulting polymers were characterized by different analytical techniques (NMR, MALDI-ToF MS, GPC, DSC, and ATG). The resulting partially green polymers, having tertiary phosphine sulfide with P-N side chain functionalities along the main chain of polymers are the sensitive film at the surface of a gold electrode for the impedimetric detection of Cd, Ni, Pb and Hg. The bio-based poly(ether-phosphoramide) functionalized with N-methylpiperazine modified sensor showed better analytical performance than petrochemical based polymers for the detection of Ni2+. A detection limit of 50 pM was obtained which is very low compared to the previously published electrochemical sensors for nickel detection.


Assuntos
Técnicas Biossensoriais , Níquel , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Eletrodos , Éter , Éteres , Limite de Detecção , Níquel/química , Fosforamidas , Polímeros/química , Sulfetos
5.
Talanta ; 243: 123351, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35272157

RESUMO

Phenolic and substituted phenol based resoles are commonly used in the formulation of can coatings. However, migration analyses of these coatings are very little described compared to other coating technologies. While epoxy and polyester have well known migrants with defined formation mechanisms, Non-Intentionally Added Substances (NIAS) specifically related to the phenolic resin are hardly studied in the literature. The goal of the publication is to further explore the influence of the phenolic resole, used in the formulation of can coatings, on extracted NIAS's nature. Six different model polyester-phenolic can coatings were formulated each with a specific phenol, cresol or tertbutylphenol-based resole. Can coating films were extracted for 24 h at 40 °C in acetonitrile before analysis. NIAS identification was done using gas chromatography separation coupled to high resolution mass spectrometry (HRMS) and nuclear magnetic resonance (NMR) spectroscopy analyses. Cyclic polyester oligomers were found in all extracts, with oligomers found in a range of 10 µg/dm2 to 226 µg/dm2, without specific influence of the resole used in formulation. While very few or no peaks were detected from cresol- and phenol-based resoles, 48 peaks were specifically observed in coating extracts of formulas with tertbutylphenol-based resoles as well as in their respective resoles. The most intense peaks were identified as aldehyde compounds by HRMS and NMR analysis. These aldehydes were semi-quantified in similar proportions as polyester oligomers. The presence of such aldehydes has never been reported in the literature regarding NIAS in can coatings. Further study will then be needed to better understand the aldehyde formation mechanism and assess the toxicological profile of such chemicals.


Assuntos
Embalagem de Alimentos , Poliésteres , Aldeídos/análise , Contaminação de Alimentos/análise , Cromatografia Gasosa-Espectrometria de Massas , Extratos Vegetais , Poliésteres/química
6.
Artigo em Inglês | MEDLINE | ID: mdl-34731745

RESUMO

Neroli essential oil (EO), extracted from bitter orange blossoms, is one of the most expensive natural products on the market due to its poor yield and its use in fragrance compositions, such as cologne. Multiple adulterations of neroli EO are found on the market, and several authentication strategies, such as enantioselective gas chromatography (GC) and isotope ratio mass spectrometry (IRMS), have been developed in the last few years. However, neroli EO adulteration is becoming increasingly sophisticated, and analytical improvements are needed to increase precision. Enantiomeric and compound-specific isotopic profiling of numerous metabolites using multidimensional GC and GC-C/P-IRMS was carried out. These analyses proved to be efficient for geographical tracing, especially to distinguish neroli EO of Egyptian origin. In addition, δ2H values and enantioselective ratios can identify an addition of 10% of petitgrain EO. These results demonstrate that enantioselective and stable isotopic metabolite fingerprint determination is currently a necessity to control EOs.


Assuntos
Isótopos de Carbono/química , Citrus/química , Deutério/química , Óleos Voláteis/química , Óleos de Plantas/química , Isótopos de Carbono/metabolismo , Cromatografia Gasosa , Citrus/metabolismo , Deutério/metabolismo , Contaminação de Medicamentos , Flores/química , Cromatografia Gasosa-Espectrometria de Massas , Óleos Voláteis/metabolismo , Óleos de Plantas/metabolismo , Estereoisomerismo
7.
Int J Pharm ; 593: 120138, 2021 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-33278497

RESUMO

Plant-based remedies have been widely used for the management of variable diseases due to their safety and less side effects. In the present study, we investigated Saussurea lappa CB. Clarke. (SL) given its largely reported medicinal effects. Specifically, our objective was to provide an insight into a new polymethyl methacrylate based nanocapsules as carriers of SL essential oil and characterize their biologic functions. The nanoparticles were prepared by nanoprecipitation technique, characterized and analyzed for their cytotoxicity, anti-inflammatory, anti-Alzheimer and antidiabetic effects. The results revealed that the developed nanoparticles had a diameter around 145 nm, a polydispersity index of 0.18 and a zeta potential equal to +45 mV and they did not show any cytotoxicity at 25 µg·mL-1. The results also showed an anti-inflammatory activity (reduction in metalloprotease MMP-9 enzyme activity and RNA expression of inflammatory cytokines: TNF-α, GM-CSF and IL1ß), a high anti-Alzheimer's effect (IC50 around 25.0 and 14.9 µg·mL-1 against acetylcholinesterase and butyrylcholinesterase, respectively), and a strong antidiabetic effect (IC50 were equal to 22.9 and 75.8 µg·mL-1 against α-amylase and α-glucosidase, respectively). Further studies are required including the in vivo studies (e.g., preclinical), the pharmacokinetic properties, the bioavailability and the underlying associated metabolic pathways.


Assuntos
Nanocápsulas , Óleos Voláteis , Saussurea , Anti-Inflamatórios/farmacologia , Inibidores da Colinesterase/farmacologia , Hipoglicemiantes/farmacologia , Óleos Voláteis/farmacologia , Extratos Vegetais
8.
Molecules ; 25(15)2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32751545

RESUMO

Three new compounds, a dihydrobenzofuran (coumaran) derivative (compound 1) and two pterocarpans (compounds 2 and 3) were isolated from a root extract of Calicotome villosa growing wild in Corsica. Their structures were elucidated using 1D and 2D NMR spectroscopy and MS/MS as 2-(1-methylethenyl)-5-hydroxy-6-carbomethoxy-2,3-dihydro-benzofuran, 4,9-dihydroxy-3-methoxy-2-dimethylallylpterocarpan, and 4,9-dihydroxy-3',3'-dimethyl-2,3-pyranopterocarpan.


Assuntos
Benzofuranos/química , Fabaceae/química , Extratos Vegetais/química , Pterocarpanos/química , Benzofuranos/análise , Benzofuranos/isolamento & purificação , Ressonância Magnética Nuclear Biomolecular , Extratos Vegetais/análise , Extratos Vegetais/isolamento & purificação , Raízes de Plantas/química , Pterocarpanos/análise , Pterocarpanos/isolamento & purificação
9.
Food Chem ; 333: 127506, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-32679417

RESUMO

Artichoke floral stems (AFS) food waste by-products were examined for their phytochemical constituents and their in vitro and in vivo biological activities. Although that the highest total phenol content and total flavonoid content were found in ethyl acetate extract, methanol extract possessed the strongest DPPH and ABTS radical scavenging activity, and showed the highest reducing ferric antioxidant power (FRAP). The anti-acetylcholinesterase activity was higher in butanol extract, whereas the ethyl acetate extract had the highest inhibitory effect on heat-induced protein denaturation. In alloxan-induced diabetic mice, the AFS methanol extract (AFSE) rich in caffeoylquinic acids and flavones reduced blood glucose, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase, creatinine, and improved liver, and renal antioxidative status. Administration of AFSE to diabetic mice reduced total cholesterol, triglycerides, LDL-cholesterol, and the atherogenic index of plasma (AIP) suggesting its hypolipidemic action. Overall, AFS could be considered as attractive source of health-promoting ingredients.


Assuntos
Cynara scolymus/química , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Alanina Transaminase , Animais , Antioxidantes/química , Antioxidantes/metabolismo , Bactérias/efeitos dos fármacos , Glicemia/análise , Candida albicans/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cynara scolymus/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/patologia , Flavonoides/análise , Flores/química , Flores/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Fenóis/análise , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Compostos Fitoquímicos/uso terapêutico , Extratos Vegetais/farmacologia , Caules de Planta/química , Caules de Planta/metabolismo , Espectrometria de Massas por Ionização por Electrospray
10.
Appl Biochem Biotechnol ; 189(2): 576-588, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31069629

RESUMO

In this study, peroxidases (PODs) from three waste by-products: broad bean pods (BBP), pea pods (PP), and artichoke stems (ARS) were purified and their optimal conditions were determined for the first time. The purification process resulted in 4.32, 7.21, and 8.9% of POD recoveries for PP, ARS, and BBP, respectively. They were purified 2.12-, 32.97-, and 10-fold with specific activities of 27.26, 266.43, and 27 U/mg of protein, respectively. Analysis of their optimal conditions showed that POD purified from BBP and PP exhibited the highest activity at 60 °C temperature and pH 6 and 8 with strong affinity with catechol substrate (Km of 0.356 and 0.189 mM; Vmax of 0.08 and 0.041 µM/min for BBP and PP, respectively). The highest activity of ARS POD was obtained under the following conditions: temperature at 50 °C, pH from 6 to 8, and guaiacol as substrate (Km 0.375 mM; Vmax 0.012 µM/min). Apart from giving the opportunity for recycling the food industry wastes, the studied waste by-products could represent an alternative source of PODs that could find several applications in the biotechnological, chemical, and food industries.


Assuntos
Cynara scolymus/enzimologia , Peroxidases/isolamento & purificação , Pisum sativum/enzimologia , Proteínas de Plantas/isolamento & purificação , Resíduos , Peroxidases/química , Proteínas de Plantas/química
11.
J Food Sci Technol ; 55(8): 3065-3076, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30065416

RESUMO

Enzyme-assisted extraction has emerged as an attractive green, cost-effective and high bioactive yielding technology by which desired bioactives with preserved or better efficacy are released. In the present study, the ability of cellulase, hemicellulase and their binary mixture (cellulase:hemicellulase; 1:1) in improving the extraction of essential oils from coriander (Coriandrum sativum L.) seeds, or the residue by-products from the distillation process containing value-added phytochemicals (fatty acids and phenolics) were evaluated. Cellulase and the binary mixture improved the extraction of essential oils by 44.2 and 40%, respectively. Application of enzymes was associated with increased amount of oxygenated terpenes in the essential oils derived from enzyme-treated samples. Linalool, camphor and geranyl acetate were the prominent compounds. From the hydrodistillation residues, a better recovery of petroselinic-rich oil with a good nutritional quality was also observed in enzyme-treated seeds. They also contained an appreciable amount of polyphenols and showed an improved antioxidant activity as revealed by the DPPH, FRAP and cellular antioxidant activity assays. The results suggested that enzyme pre-treatment allowed better recovery without alteration of the essential oil composition. The hydrodistillation residues obtained could be potentially exploited for the development of functional food ingredients and nutraceuticals.

12.
J Food Sci Technol ; 55(4): 1582-1590, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29606774

RESUMO

The fatty acid, essential oil compositions and their respective antioxidant and antibacterial activities was determined in Schinus terebinthifolius Raddi leaves and twigs. The lipid content ranged from 1.75 to 4.65% in twigs and leaves, respectively. Thirteen fatty acids were identified with α-linolenic (C18:3), palmitic (C16:0) and linoleic (C18:2) acids being the main components. The essential oils of both organs were characterized by a high amount of monoterpene hydrocarbons (68.91-74.88%) with α-phellandrene (33.06-36.18%), α-pinene (14.85-15.18%) and limonene (6.62-8.79%) being the chief components. The DPPH˙ radical scavenging assay revealed that both oils have a very weak antiradical activity. In contrast, they showed an appreciable antibacterial activity against the gram-positive Enterococcus feacium (ATCC 19434) and Streptococcus agalactiae (ATCC 13813) bacteria. These results suggest that leaves and twigs of S. terebinthifolius could be considered as an important dietary source of health promoting phytochemicals and has a good potential for use in food industry and pharmacy.

13.
Des Monomers Polym ; 20(1): 221-233, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29491795

RESUMO

In the present work, we propose the synthesis of a new family of sugar derived 1,4:3,6-dianhydrohexitol based AA/AB-type monomers. Unprecedented diacids based on Isomannide and Isoidide were elaborated with high yields and showed interestingly high melting point ranges (240-375 °C). Optimization of reaction conditions (temperature, time of reaction, and reactant ratios) has been investigated to synthesize the key intermediate of a set of AB monomers with acid, ester, and acid chloride functionalities. Isosorbide based ether benzoic acid AB monomer was polymerized and characterized by NMR and DSC techniques. The results show a semicrystalline behavior of the obtained polymer thanks to the controlled stereoregular arrangement of the AB starting monomer.

14.
J Mol Recognit ; 30(4)2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27885729

RESUMO

New biosourced chiral cross-linkers were reported for the first time in the synthesis of methyltestosterone (MT) chiral molecularly imprinted polymers (cMIPs). Isosorbide and isomannide, known as 1,4:3,6-dianhydrohexitols, were selected as starting diols. The cMIPs were synthesized following a noncovalent approach via thermal radical polymerization and monitored by Raman spectroscopy. These cross-linkers were fully characterized by 1 H and 13 C nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry. The cross-polarization magic angle spinning 13 C NMR, Fourier transform infrared spectroscopy, scanning electron microscopy, and specific surface areas following the Brunauer-Emmett-Teller (BET) method were used to characterize the cMIPs. The effect of stereochemistry of cross-linkers on the reactivity of polymerization, morphology, and adsorption-recognition properties of the MIP was evaluated. The results showed that the cMIP exhibited an obvious improvement in terms of rebinding capacity for MT as compared with the nonimprinted polymer (NIP). The highest binding capacity was observed for cMIP-Is (27.298 mg g-1 ) for high concentrations (500 mg L-1 ). However, the isomannide homologue cMIP-Im showed higher recovery-up to 65% and capacity for low concentrations (15 mg L-1 ). The experimental data were properly fitted by the Freundlich adsorption isothermal model.


Assuntos
Impressão Molecular/métodos , Polímeros/síntese química , Metiltestosterona/metabolismo , Microscopia Eletrônica de Varredura , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Polímeros/química , Polímeros/metabolismo , Extração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Estereoisomerismo
15.
J Oleo Sci ; 65(8): 655-61, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-27430383

RESUMO

The composition of the fatty acids of the roots and aerial parts of Aritolochia longa (Aristolacheae) and Bryonia dioïca (Cucurbutaceae) was analyzed by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The oils extracted from the aerial parts of both species were rich in polyunsaturated fatty acids with the essential linolenic and linoleic acids being the most prominent compounds. Oleic and linoleic acids were the majors fatty acids in the roots of both species. Whatever the plant part analyzed and the species, the saturated fatty acids were predominantly composed of palmitic and stearic acids. The antibacterial activity, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the lipid extracts were determined against a panel of five bacterial strains. The results showed that the sensitivity to the lipid extracts was different for the test bacterial strains, and the susceptibility of gram positive bacteria was found to be greater than gram negative bacteria. The antibacterial activity of the root lipid extracts was particularly important against Enterococcus feacium (CMI value of 125 µg/mL; CMB values > 250 µg/mL) and Streptococcus agalactiae (CMI value of 125 µg/mL; CMB values 250 µg/mL for A. longa roots). These results indicate that A. longa and B. dioïca could be considered as good sources of essential fatty acids which can act as natural antibacterial agents.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Aristolochia/química , Aristolochia/crescimento & desenvolvimento , Bryonia/química , Bryonia/crescimento & desenvolvimento , Ácidos Graxos/análise , Antibacterianos/isolamento & purificação , Relação Dose-Resposta a Droga , Ácidos Graxos/química , Ácidos Graxos/isolamento & purificação , Ácidos Graxos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Componentes Aéreos da Planta/química , Raízes de Plantas/química , Relação Estrutura-Atividade , Tunísia
16.
Chemosphere ; 156: 245-251, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27179242

RESUMO

Boscalid is a new-generation fungicide that has been detected in several bee matrices. The objective of this work was to characterize boscalid metabolites in honeybees based on in vivo experimentation, and next to verify the presence of theses metabolites into honeybees from colonies presenting troubles. A methodology based on complementary mass spectrometric tools, namely ultra-high performance liquid chromatography coupled to high-resolution mass spectrometry (UHPLC-QToF) or triple quadrupole mass spectrometry (UHPLC-QqQ) was implemented. Honeybees were sprayed with boscalid, at field rate (to induce the metabolization process) and the parent compound with its generated metabolites were then extracted using modified EU-QuEChERS method. The mass characteristics including exact mass, isotopic profile and mass fragments allowed assuming the structure of several metabolites. Some of them were unambiguously identified by comparison with synthesized analytical standards. The metabolites were resulted from hydroxylation and dechlorination of the parent compound as well as the substitution of a chlorine atom with an hydroxyl group. The metabolites were then quantified in bee samples collected from various beehives located in France. Boscalid and three of its metabolites were present in some samples at a level ranged between 0.2 and 36.3 ng/g.


Assuntos
Abelhas/metabolismo , Compostos de Bifenilo/análise , Compostos de Bifenilo/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Fungicidas Industriais/análise , Espectrometria de Massas/métodos , Niacinamida/análogos & derivados , Animais , França , Niacinamida/análise , Niacinamida/metabolismo
17.
Rapid Commun Mass Spectrom ; 30(9): 1108-14, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-27060838

RESUMO

RATIONALE: To develop more eco-friendly laundry detergents, renewable surfactants synthesized from vegetal sources are increasingly being used. In a more stringent regulation context, the determination of bio-sourced surfactant origin thus appears essential to assess the claims of detergent manufacturers. Radiocarbon determination, the standard method for the analysis of bio-sourced materials, is an expensive technique, so there is a need for a cheaper method. METHODS: Here, the use of an elemental analyzer linked to isotope-ratio mass spectrometry (EA/IRMS) is evaluated as an alternative approach to the official method. The δ(18) O, δ(13) C and δ(2) H isotope-ratio values were determined to investigate the bio-sourced origin of surfactant raw materials and mixtures. RESULTS: A sample library of 26 commercial surfactants representative of detergent raw materials was first analyzed by EA/IRMS. The δ(18) O, δ(13) C and δ(2) H values allowed discrimination of synthetic and bio-sourced surfactants. Moreover, in this latter group, C4 plant-derived surfactants were distinguished by their δ(13) C values. Binary and ternary mixtures made of synthetic and bio-sourced surfactants were also analyzed and indicated a linear relationship between mixture isotope-ratio values and surfactant proportions. CONCLUSIONS: IRMS represents a viable alternative to radiocarbon determination for the evaluation of surfactant bio-sourced origin. It is a faster and cheaper technique, allowing discrimination of petroleum- and biomass-derived surfactants and identification of their carbon sources (C4 or C3 plants).

18.
Anal Bioanal Chem ; 408(17): 4669-81, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27098933

RESUMO

In a stricter legislative context, greener detergent formulations are developed. In this way, synthetic surfactants are frequently replaced by bio-sourced surfactants and/or used at lower concentrations in combination with enzymes. In this paper, a LC-MS/MS method was developed for the identification and quantification of enzymes in laundry detergents. Prior to the LC-MS/MS analyses, a specific sample preparation protocol was developed due to matrix complexity (high surfactant percentages). Then for each enzyme family mainly used in detergent formulations (protease, amylase, cellulase, and lipase), specific peptides were identified on a high resolution platform. A LC-MS/MS method was then developed in selected reaction monitoring (SRM) MS mode for the light and corresponding heavy peptides. The method was linear on the peptide concentration ranges 25-1000 ng/mL for protease, lipase, and cellulase; 50-1000 ng/mL for amylase; and 5-1000 ng/mL for cellulase in both water and laundry detergent matrices. The application of the developed analytical strategy to real commercial laundry detergents enabled enzyme identification and absolute quantification. For the first time, identification and absolute quantification of enzymes in laundry detergent was realized by LC-MS/MS in a single run. Graphical Abstract Identification and quantification of enzymes by LC-MS/MS.


Assuntos
Cromatografia Líquida/métodos , Detergentes/química , Enzimas/análise , Lavanderia , Espectrometria de Massas em Tandem/métodos , Sequência de Aminoácidos , Limite de Detecção , Reprodutibilidade dos Testes , Extração em Fase Sólida
19.
Anal Chim Acta ; 915: 36-48, 2016 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-26995638

RESUMO

This paper presents the analysis of surfactants in complex mixtures using Raman spectroscopy combined with signal extraction (SE) methods. Surfactants are the most important component in laundry detergents. Both their identification and quantification are required for quality control and regulation purposes. Several synthetic mixtures of four surfactants contained in an Ecolabel laundry detergent were prepared and analyzed by Raman spectroscopy. SE methods, Independent Component Analysis and Multivariate Curve Resolution, were then applied to spectral data for surfactant identification and quantification. The influence of several pre-processing treatments (normalization, baseline correction, scatter correction and smoothing) on SE performances were evaluated by experimental design. By using optimal pre-processing strategy, SE methods allowed satisfactorily both identifying and quantifying the four surfactants. When applied to the pre-processed Raman spectrum of the Ecolabel laundry detergent sample, SE models remained robust enough to predict the surfactant concentrations with sufficient precision for deformulation purpose. Comparatively, a supervised modeling technique (PLS regression) was very efficient to quantify the four surfactants in synthetic mixtures but appeared less effective than SE methods when applied to the Raman spectrum of the detergent sample. PLS seemed too sensitive to the other components contained in the laundry detergent while SE methods were more robust. The results obtained demonstrated the interest of SE methods in the context of deformulation.

20.
J Agric Food Chem ; 64(8): 1664-75, 2016 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-26853463

RESUMO

A comprehensive analysis of the responses of Nigella sativa L. to elevated zinc concentrations was assessed in pot experiments. Zn excess supply did not affect the germination but drastically reduced radicle elongation. A concentration-dependent reduction in all growth parameters, yield, and yield components was observed. With the increasing Zn concentrations, total lipid contents decreased and changes in fatty composition toward the production of saturated ones were underscored. Despite the reduction in the seeds essential oil yield, a redirection of the terpene metabolism toward the synthesis of oxygenated compounds has been evidenced. A significant increase in the total phenols and flavonoids contents concomitant with improved antioxidant activities has also been found. Collectively, these results highlight the possible use of N. sativa L. in phytoremediation applications, on the one hand, and that Zn excess could represent an excellent alternative to improve the nutritional attributes of this important species, on the other hand.


Assuntos
Antioxidantes/metabolismo , Metabolismo dos Lipídeos , Fenóis/metabolismo , Sementes/crescimento & desenvolvimento , Terpenos/metabolismo , Zinco/metabolismo , Antioxidantes/análise , Germinação , Nigella sativa/química , Nigella sativa/crescimento & desenvolvimento , Nigella sativa/metabolismo , Fenóis/análise , Sementes/química , Sementes/metabolismo , Terpenos/análise , Zinco/análise
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