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1.
Molecules ; 28(13)2023 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-37446900

RESUMO

L-Dopa, a bioactive compound naturally occurring in some Leguminosae plants, is the most effective symptomatic drug treatment for Parkinson's disease. During disease progression, fluctuations in L-DOPA plasma levels occur, causing motor complications. Sensing devices capable of rapidly monitoring drug levels would allow adjusting L-Dopa dosing, improving therapeutic outcomes. A novel amperometric biosensor for L-Dopa detection is described, based on tyrosinase co-crosslinked onto a graphene oxide layer produced through electrodeposition. Careful optimization of the enzyme immobilization procedure permitted to improve the long-term stability while substantially shortening and simplifying the biosensor fabrication. The effectiveness of the immobilization protocol combined with the enhanced performances of electrodeposited graphene oxide allowed to achieve high sensitivity, wide linear range, and a detection limit of 0.84 µM, suitable for L-Dopa detection within its therapeutic window. Interference from endogenous compounds, tested at concentrations levels typically found in drug-treated patients, was not significant. Ascorbic acid exhibited a tyrosinase inhibitory behavior and was therefore rejected from the enzymatic layer by casting an outer Nafion membrane. The proposed device was applied for L-Dopa detection in human plasma, showing good recoveries.


Assuntos
Técnicas Biossensoriais , Grafite , Humanos , Levodopa , Monofenol Mono-Oxigenase , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas
2.
Anal Bioanal Chem ; 414(27): 7805-7812, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36121471

RESUMO

The chemical composition of wine samples comprises numerous bioactive compounds responsible for unique flavor and health-promoting properties. Thus, it's important to have a complete overview of the metabolic profile of new wine products in order to obtain peculiar information in terms of their phytochemical composition, quality, and traceability. To achieve this aim, in this work, a mass spectrometry-based phytochemical screening was performed on seven new wine products from Villa D'Agri in the Basilicata region (Italy), i.e., Aglianico Bianco, Plavina, Guisana, Giosana, Malvasia ad acino piccolo, Colata Murro and Santa Sofia. Ultra-high-resolution mass spectrometry data were processed into absorption mode FT-ICR mass spectra, in order to remove artifacts and achieve a higher resolution and lower levels of noise. Accurate mass-to-charge ratio (m/z) values were converted into putative elemental formulas. Therefore, 2D van Krevelen diagrams were used as a tool to obtain molecular formula maps useful to perform a rapid and more comprehensive analysis of the wine sample metabolome. The presence of important metabolite classes, i.e., fatty acid derivatives, amino acids and peptides, carbohydrates and phenolic derivatives, was assessed. Moreover, the comparison of obtained metabolomic maps revealed some differences among profiles, suggesting their employment as metabolic fingerprints. This study shed some light on the metabolic composition of seven new Italian wine varieties, improving their value in terms of related bioactive compound content. Moreover, different metabolomic fingerprints were obtained for each of them, suggesting the use of molecular maps as innovative tool to ascertain their unique metabolic profile.


Assuntos
Vinho , Aminoácidos/análise , Carboidratos/análise , Ácidos Graxos/análise , Espectrometria de Massas , Metabolômica/métodos , Peptídeos/análise , Vinho/análise
3.
Molecules ; 27(21)2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36364292

RESUMO

L-Dopa (LD), a substance used medically in the treatment of Parkinson's disease, is found in several natural products, such as Vicia faba L., also known as broad beans. Due to its low chemical stability, LD analysis in plant matrices requires an appropriate optimization of the chosen analytical method to obtain reliable results. This work proposes an HPLC-UV method, validated according to EURACHEM guidelines as regards linearity, limits of detection and quantification, precision, accuracy, and matrix effect. The LD extraction was studied by evaluating its aqueous stability over 3 months. The best chromatographic conditions were found by systematically testing several C18 stationary phases and acidic mobile phases. In addition, the assessment of the best storage treatment of Vicia faba L. broad beans able to preserve a high LD content was performed. The best LD determination conditions include sun-drying storage, extraction in HCl 0.1 M, chromatographic separation with a Discovery C18 column, 250 × 4.6 mm, 5 µm particle size, and 99% formic acid 0.2% v/v and 1% methanol as the mobile phase. The optimized method proposed here overcomes the problems linked to LD stability and separation, thus contributing to the improvement of its analytical determination.


Assuntos
Vicia faba , Cromatografia Líquida de Alta Pressão/métodos , Vicia faba/química , Levodopa , Metanol
4.
Molecules ; 26(13)2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34279443

RESUMO

Diterpenoid alkaloids are natural compounds having complex structural features with many stereo-centres originating from the amination of natural tetracyclic diterpenes and produced primarily from plants in the Aconitum, Delphinium, Consolida genera. Corals, Xenia, Okinawan/Clavularia, Alcyonacea (soft corals) and marine sponges are rich sources of diterpenoids, despite the difficulty to access them and the lack of availability. Researchers have long been concerned with the potential beneficial or harmful effects of diterpenoid alkaloids due to their structural complexity, which accounts for their use as pharmaceuticals as well as their lousy reputation as toxic substances. Compounds belonging to this unique and fascinating family of natural products exhibit a broad spectrum of biological activities. Some of these compounds are on the list of clinical drugs, while others act as incredibly potent neurotoxins. Despite numerous attempts to prepare synthetic products, this review only introduces the natural diterpenoid alkaloids, describing 'compounds' structures and classifications and their toxicity and bioactivity. The purpose of the review is to highlight some existing relationships between the presence of substituents in the structure of such molecules and their recognised bioactivity.


Assuntos
Alcaloides/farmacologia , Produtos Biológicos/farmacologia , Diterpenos/farmacologia , Animais , Anti-Infecciosos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Humanos , Testes de Toxicidade
5.
Ecotoxicol Environ Saf ; 162: 454-463, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30015192

RESUMO

Plant-derived substances, because of high biological activity, arouse interest of many scientists. Thus, plant extracts and pure substances are intensively studied on various insects as potential insecticides. In such studies, D. melanogaster is one of the most important model organisms. In our studies, we analysed the contents of two plant extracts and tested the activity of their main components against fruit flies and compared observed effects to effects caused by crude extracts. Then, we assessed the development of the next, unexposed generation. The chemical analysis of extracts revealed the presence of numerous glycoalkaloids and glucosinolates in Solanum nigrum and Armoracia rusticana extracts. These extracts, as well as their main components, revealed lethal and sublethal effects, such as the altered developmental time of various life stages and malformations of imagoes. Interestingly, the results for the extracts and pure main compounds often varied. Some of the results were also observed in the unexposed generation. These results confirm that the tested plants produce a range of substances with potential insecticidal effects. The different effects of extracts and pure main components suggest the presence of minor compounds, which should be tested as insecticides.


Assuntos
Armoracia/química , Drosophila melanogaster/efeitos dos fármacos , Inseticidas/farmacologia , Estágios do Ciclo de Vida/efeitos dos fármacos , Extratos Vegetais/farmacologia , Solanum nigrum/química , Alcaloides/análise , Alcaloides/farmacologia , Animais , Drosophila melanogaster/fisiologia , Glucosinolatos/análise , Glucosinolatos/farmacologia , Insetos/efeitos dos fármacos , Reprodução
6.
Artigo em Inglês | MEDLINE | ID: mdl-26191987

RESUMO

Stability and removal of spironolactone (SP) from wastewater produced at Al-Quds University Campus were investigated. Kinetic studies on both pure water and wastewater coming from secondary treatment (activated sludge) demonstrated that the potassium-sparing diuretic (water pill), spironolactone, underwent degradation to its hydrolytic derivative, canrenone, in both media. The first-order hydrolysis rate of SP in activated sludge at 25°C (3.80 × 10(-5) s(-1)) was about 49-fold larger than in pure water (7.4 × 10(-7) s(-1)). The overall performance of the wastewater treatment plant (WWTP) installed in the University Campus was assessed showing that more than 90% of spiked SP was removed together with its newly identified metabolites. In order to look for a technology to supplement or replace ultra-filtration membranes, the effectiveness of adsorption and filtration by micelle-clay filters for removing SP was tested in comparison with activated charcoal. Batch adsorption in aqueous suspensions was well described by Langmuir isotherms, showing a better removal by the micelle-clay material. Filtration of SP water solutions by columns filled with a mixture of sand and a micelle-clay complex showed complete removal of the drug at concentrations higher than in sand/activated-charcoal filled filters.


Assuntos
Silicatos de Alumínio/química , Carvão Vegetal/química , Esgotos/química , Espironolactona/isolamento & purificação , Águas Residuárias/química , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Argila , Israel , Micelas
7.
Environ Technol ; 35(13-16): 1945-55, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24956788

RESUMO

Stability and removal of dexamethasone sodium phosphate (DSP) from wastewater produced at Al-Quds University Campus were investigated. Kinetic studies in both pure water and wastewater coming from secondary treatment (activated sludge) demonstrated that the anti-inflammatory DSP underwent degradation to its hydrolytic derivative, dexamethasone, in both media. The first-order hydrolysis rate of DSP in activated sludge at 25 degrees C (3.80 x 10(-6) s-1) was about 12-fold larger than in pure water (3.25 x 10(-7) s-1). The overall performance of the wastewater treatment plant (WWTP) installed in the University Campus was also assessed showing that 90% of spiked DSP was removed together with its newly identified metabolites by the ultra-filtration (UF) system, which consists of a UF hollow fibre (HF) with a 100-kDa cutoff membrane as the pre-polishing stage for the UF spiral wound with a 20-kDa cutoffmembrane. In testing other technologies, the effectiveness of adsorption and filtration by micelle-clay (MC) preparation for removing DSP was ascertained in comparison with activated charcoal. Batch adsorption in aqueous suspensions of the MC composite and activated carbon was well described by Langmuir isotherms showing the best results for MC material. Filtration of DSP water solutions demonstrated a significant advantage of columns filled in with a mixture of sand and MC complex in comparison with activated carbon/sand filters.


Assuntos
Silicatos de Alumínio/química , Dexametasona/análogos & derivados , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água , Adsorção , Argila , Dexametasona/isolamento & purificação , Termodinâmica , Águas Residuárias/química
8.
Environ Sci Pollut Res Int ; 31(12): 18887-18899, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38353820

RESUMO

The scarcity of freshwater for agriculture in many regions has led to the application of sewage and saline water for irrigation. Irrigation with non-conventional water sources could become a non-harmful process for plant cultivation, and the effects of their use on crops should be monitored in order to develop optimal management strategies. One possibility to overcome potential barriers is to use biostimulants such as Trichoderma spp. fungi. Tomato is a crop of great economic importance in the world. This study investigated the joint effects of Trichoderma afroharzianum T-22 on tomato plants irrigated with simulated unconventional waters. The experiment consisted of a control and three water treatments. In the control, the plants were watered with distilled water. The three water treatments were obtained by using an irrigation water added with nitrogen, a wastewater effluent, and a mixed groundwater-wastewater effluents. Potted tomato plants (variety Bobcat) were grown in a controlled growth chamber. Antioxidant activity, susceptibility to the aphids Macrosiphum euphorbiae, and tomato plant growth parameters were estimated. Trichoderma afroharzianum T-22 had a positive effect on plant growth and antioxidant defenses when plants were irrigated with distilled water. Instead, no significant morphological effects induced by T. afroharzianum T-22 on plants were observed when unconventional water was used for irrigation. However, inoculation with T. afroharzianum T-22 activated a stress response that made the colonized plants more susceptible to aphid development and increased their fecundity and longevity. Thanks to this study, it may be possible for the first time to open a new discussion on the practical possibility of using reclaimed wastewater for crop irrigation with the addition of a growth-promoting fungal symbiont.


Assuntos
Afídeos , Hypocreales , Solanum lycopersicum , Trichoderma , Animais , Águas Residuárias , Afídeos/fisiologia , Antioxidantes , Trichoderma/fisiologia , Irrigação Agrícola
9.
J Mass Spectrom ; 58(10): e4952, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37401097

RESUMO

An analytical method based on ultrasound assisted extraction (UAE) and liquid chromatography coupled to electrospray tandem mass spectrometry (LC-ESI/MS/MS) was validated and applied for determining L-dopa in four ecotypes of Fagioli di Sarconi beans (Phaseolus vulgaris L.), marked with the European label PGI (Protected Geographical Indication). The selectivity of the proposed method was ensured by the specific fragmentation of the analyte. Simple isocratic chromatographic conditions and mass spectrometric detection in multiple reaction monitoring (MRM) acquisition mode were used for sensitive quantification. The LC-ESI/MS/MS method was validated within a linear range of 0.001-5.000 µg/mL. Values of 0.4 and 1.1 ng/mL were obtained for the limits of detection and quantification, respectively. The repeatability, inter-day precision, and recovery values ranges were 0.6%-4.5%, 5.4%-9.9%, and 83%-93%, respectively. Fresh and dried beans, as well as pods, cultivated exclusively with organic methods avoiding any synthetic fertilizers and pesticides were analyzed showing an L-dopa content ranging from 0.020 ± 0.005 to 2.34 ± 0.05 µg/g dry weight.


Assuntos
Praguicidas , Phaseolus , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Phaseolus/química , Levodopa , Cromatografia Líquida de Alta Pressão
10.
Environ Sci Pollut Res Int ; 29(38): 58201-58211, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35359212

RESUMO

Levofloxacin (LFX) is a widely used antibiotic medication. Persistent traces of LFX in water and wastewater may induce bacterial resistance. Photon-driven advanced oxidation processes (AOPs) can assist in attaining complete abatement of LFX for environmental protection. This work benchmarks different solar AOPs based on hydroxyl radical (OH•) and sulphate radical (SO4•-) chemistry. Other oxidant precursors, as radical sources, were used to selectively control the generation of either hydroxyl radical (i.e., H2O2), sulphate radical (i.e., peroxydisulphate (PDS)), or a controlled mixture ratio of both OH•/SO4•- (i.e., peroxymonosulphate (PMS)). The influence of pH on degradation performance was evaluated using unbuffered and buffered solutions. Simulated irradiation/PMS process exhibited a strong pH-dependence attaining partial degradation of ca. 56% at pH 5 up to complete degradation at pH 7. Despite the similitudes on the abatement of target pollutant LFX in pristine solutions, only simulated irradiation/PDS treatment achieved effective abatement of LFX in wastewater samples given the higher selectivity of SO4•-. Toxicity tests were conducted with Escherichia coli (LMG2092) and Micrococcus flavus (DSM1790), demonstrating successful inhibition of the antibiotic character of polluted waters, which would contribute to preventing the development of resistant bacterial strains. Finally, a degradative pathway was suggested from the by-products and intermediates identified by LC-MS. Results demonstrate that the degradation of specific functional groups (i.e., piperazine ring) is associated with the loss of antibacterial character of the molecule.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Antibacterianos/farmacologia , Escherichia coli , Peróxido de Hidrogênio/química , Radical Hidroxila/química , Cinética , Levofloxacino/farmacologia , Micrococcus , Oxirredução , Luz Solar , Águas Residuárias/química , Poluentes Químicos da Água/análise
11.
J Environ Sci Health B ; 46(6): 449-53, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21726140

RESUMO

Different degradation methods have been applied to assess the suitability of advanced oxidation process (AOPs) to promote mineralization of imazethapyr [(RS)-5-ethyl-2-(4-isopropyl-4-methyl-5-oxo-2-imidazolin-2-yl)nicotinic acid], a widely used imidazolinone class herbicide, the persistence of which has been demonstrated in surface and ground waters destined to human uses. Independent of the oxidation process assessed, the decomposition of imazethapyr always followed a pseudo-first order kinetic. The direct UV-irradiation (UV) of the herbicide as well as its oxidation with ozone (O3), and hydrogen peroxide tied to UV-irradiation (H2O2/UV) were sufficiently slow to permit the identification of intermediate products, the formation pathway of which has been proposed. Ozonation joined to UV-irradiation (O3/UV), ozonation joined to titanium dioxide photo-catalysis (TiO2/UV+O3), sole photo-catalysis (TiO2/UV), and photo-catalysis reinforced with hydrogen peroxide-oxidation (TiO2/UV+H2O2) were characterized by a faster degradation and rapid formation of a lot of small molecules, which were quickly degraded to complete mineralization. The most effective oxidation methods were those using titanium dioxide photo-catalysis enhanced either by ozonation or hydrogen peroxide. Most of all, these last processes were useful to avoid the development of dangerous by-products.


Assuntos
Herbicidas/química , Ácidos Nicotínicos/química , Poluentes Químicos da Água/química , Catálise , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Resíduos Industriais , Oxidantes Fotoquímicos/química , Oxidantes Fotoquímicos/efeitos da radiação , Oxirredução/efeitos dos fármacos , Oxirredução/efeitos da radiação , Ozônio/química , Titânio/química , Raios Ultravioleta
12.
Toxins (Basel) ; 13(9)2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34564621

RESUMO

Glycoalkaloids, secondary metabolites abundant in plants belonging to the Solanaceae family, may affect the physiology of insect pests. This paper presents original results dealing with the influence of a crude extract obtained from Solanum nigrum unripe berries and its main constituent, solasonine, on the physiology of Galleria mellonella (Lepidoptera) that can be used as an alternative bioinsecticide. G. mellonella IV instar larvae were treated with S. nigrum extract and solasonine at different concentrations. The effects of extract and solasonine were evaluated analyzing changes in carbohydrate and amino acid composition in hemolymph by RP-HPLC and in the ultrastructure of the fat body cells by TEM. Both extract and solasonine changed the level of hemolymph metabolites and the ultrastructure of the fat body and the midgut cells. In particular, the extract increased the erythritol level in the hemolymph compared to control, enlarged the intracellular space in fat body cells, and decreased cytoplasm and lipid droplets electron density. The solasonine, tested with three concentrations, caused the decrease of cytoplasm electron density in both fat body and midgut cells. Obtained results highlighted the disturbance of the midgut and the fat body due to glycoalkaloids and the potential role of hemolymph ingredients in its detoxification. These findings suggest a possible application of glycoalkaloids as a natural insecticide in the pest control of G. mellonella larvae.


Assuntos
Corpo Adiposo/efeitos dos fármacos , Hemolinfa/efeitos dos fármacos , Inseticidas , Mariposas , Extratos Vegetais , Alcaloides de Solanáceas , Solanum nigrum/química , Animais , Sistema Digestório/efeitos dos fármacos , Sistema Digestório/ultraestrutura , Corpo Adiposo/ultraestrutura , Hemolinfa/metabolismo , Controle de Insetos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Larva/ultraestrutura , Microscopia Eletrônica de Transmissão , Mariposas/crescimento & desenvolvimento , Mariposas/metabolismo , Mariposas/ultraestrutura
13.
Anal Chem ; 82(13): 5686-96, 2010 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-20521824

RESUMO

An approach is presented that can be of general applicability for structural elucidation of naturally occurring glucosinolates (GLSs) in crude plant extracts based on the fragmentation of isotopic A and A + 2 peaks. The most important fragmentation pathways were studied by tandem mass spectrometry (MS(n), n = 2, 3) using a linear quadrupole ion trap (LTQ) upon GLSs separation by optimized reversed-phase liquid chromatography (RPLC) and electrospray ionization (ESI) in negative ion mode. As the LTQ MS analyzer ensures high sensitivity and linearity, the fragmentation behavior under collision induced dissociation (CID) of the isotopic peaks A and A + 2 as precursor ions was carefully examined. All GLSs (R-C(7)H(11)O(9)NS(2)(-)) share a common structure with at least two sulfur atoms and significant isotopic abundance of (34)S. Thus, dissociation of the +2 Da isotopomeric ions results in several fragment ion doublets containing a combination of (32)S and (34)S. Accordingly, their relative abundances allow one to speed up the structural recognition of GLSs with great confidence, as it produces more structurally informative ions than conventional tandem MS performed on A ions. This approach has been validated on known GLSs bearing two, three, four, and six sulfur atoms by comparing expected and measured isotopic peak abundance ratios (I(A)/I(A)(+2)). Both group- and compound-specific fragments were observed; the predominant pathway of fragmentation of GLSs gives rise to species having the following m/z values, [M - SO(3) - H](-), [M - 196 - H](-), [M - 178 - H](-), and [M - 162 - H](-) after H rearrangement from the R- side chain. The present strategy was successfully applied to extracts of rocket salad leaves (Eruca sativa L.), which was sufficient for the chemical identification of a not already known 6-methylsulfonyl-3-oxohexyl-GLS, a long-chain-length aliphatic glucosinolate, which contains three sulfurs and exhibits a deprotonated molecular ion at m/z 494.1.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Glucosinolatos/química , Íons/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Brassicaceae/química , Folhas de Planta/química , Isótopos de Enxofre/química , Espectrometria de Massas em Tandem
14.
Bull Environ Contam Toxicol ; 84(2): 153-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20024528

RESUMO

The semi-isolated heart bioassay was used to evaluate the effect of glycoalkaloids extracted from potato leaves on the heart contractile activity of three beetle species Zophobas atratus, Tenebrio molitor and Leptinotarsa decemlineata. The dose-response curves indicated species specific action of tested substances. Application of glycoalkaloids on the continuously perfused Z. atratus heart inhibited progressively frequency contractions; higher concentrations exerted short and reversible cardiac arrests. In the rest two beetle species tested glycoalkaloids caused no cardiotropic effect. In vivo bioassay with 1 day old Z. atratus pupae showed that the extract induces a negative inotropic effect on the heart.


Assuntos
Alcaloides/toxicidade , Besouros/fisiologia , Coração/efeitos dos fármacos , Inseticidas/toxicidade , Solanum tuberosum/química , Animais , Relação Dose-Resposta a Droga , Técnicas In Vitro , Contração Miocárdica/efeitos dos fármacos , Extratos Vegetais/farmacologia , Pupa , Tenebrio
15.
J Toxicol Environ Health A ; 72(19): 1132-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20077180

RESUMO

The effects of fenitrothion, carbaryl, and mancozeb, present in polluted water and plant extracted glycoalkaloids, were examined on hatching success of Spodoptera exigua eggs. All chemicals produced a significant decrease in hatching success, which was correlated with chemical concentration. One of the most interesting aspects of this study relates to the biological activity of glycoalkaloids.


Assuntos
Inseticidas/farmacologia , Óvulo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Spodoptera/efeitos dos fármacos , Poluentes Químicos da Água/farmacologia , Alcaloides/química , Alcaloides/farmacologia , Animais , Relação Dose-Resposta a Droga , Extratos Vegetais/química , Folhas de Planta/química , Solanum tuberosum/química
16.
Toxins (Basel) ; 11(4)2019 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-31010145

RESUMO

Eggplant contains glycoalkaloids (GAs), a class of nitrogen-containing secondary metabolites of great structural variety that may have both adverse and beneficial biological effects. In this study, we performed a complete survey of GAs and their malonylated form, in two genotypes of eggplants: A commercial cultivated type, Mirabella (Mir), with purple peel and bitter taste and a local landrace, named Melanzana Bianca di Senise (Sen), characterized by white peel with purple strip and a typical sweet aroma. Besides the analysis of their morphological traits, nineteen glycoalkaloids were tentatively identified in eggplant berry extracts based upon LC-ESI-FTICR-MS analysis using retention times, elution orders, high-resolution mass spectra, as well as high-resolution fragmentation by IRMPD. The relative signal intensities (i.e., ion counts) of the GAs identified in Mir and Sen pulp extracts showed as solamargine, and its isomers are the most abundant. In addition, anticholinesterase and antioxidant activities of the extracts were evaluated. Pulp tissue was found to be more active in inhibiting acetylcholinesterase enzyme than peel showing an inhibitory effect higher than 20% for Mir pulp. The identification of new malonylated GAs in eggplant is proposed.


Assuntos
Alcaloides , Antioxidantes , Inibidores da Colinesterase , Extratos Vegetais , Solanum melongena , Acetilcolinesterase/metabolismo , Alcaloides/análise , Alcaloides/química , Alcaloides/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Compostos de Bifenilo/química , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Cromatografia Líquida/métodos , Frutas/química , Peroxidação de Lipídeos/efeitos dos fármacos , Espectrometria de Massas/métodos , Picratos/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia
17.
Chem Biol Drug Des ; 93(3): 262-271, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30276968

RESUMO

A respected number of drugs suffer from bitter taste which results in patient incompliance. With the aim of solving the bitterness of guaifenesin, dimethyl maleate, maleate, glutarate, succinate, and dimethyl succinate prodrugs were designed and synthesized. Molecular orbital methods were utilized for the design of the ester prodrugs. The density functional theory (DFT) calculations revealed that the hydrolysis efficiency of the synthesized prodrugs is significantly sensitive to the pattern of substitution on C=C bond and distance between the nucleophile and the electrophile. The hydrolysis of the prodrugs was largely affected by the pH of the medium. The experimental t1/2 for the hydrolysis of guaifenesin dimaleate ester prodrugs in 1N HCl was the least and for guaifenesin dimethyl succinate was the highest. Functional heterologous expression of TAS2R14, a broadly tuned bitter taste receptor responding to guaifenesin, and experiments using these prodrugs revealed that, while some of the prodrugs still activated the receptor similarly or even stronger than the parent substance, succinate derivatization resulted in the complete loss of receptor responses. The predicted binding modes of guaifenesin and its prodrugs to the TAS2R14 homology model suggest that the decreased activity of the succinate derivatives may be caused by a clash with Phe247.


Assuntos
Desenho de Fármacos , Guaifenesina/química , Pró-Fármacos/síntese química , Teoria da Densidade Funcional , Guaifenesina/metabolismo , Guaifenesina/farmacologia , Células HEK293 , Meia-Vida , Humanos , Hidrólise , Cinética , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Paladar/efeitos dos fármacos
18.
Toxins (Basel) ; 10(12)2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30513736

RESUMO

BACKGROUND: Solanaceae plants produce glycoalkaloids (GAs) that affect various physiological processes of herbivorous insects and they are being tested as potential alternatives for synthetic pesticides. They cause lethal and sublethal effects. Nevertheless, their mode of action remains unclear. Therefore, we examined the effects of Solanum nigrum fruit extracts and pure glycoalkaloids on a model beetle, Tenebrio molitor. METHODS: Plant extracts or pure alkaloids were added to the food of the larvae for three days. The lipid, glycogen, and protein content in the fat body and the midgut were determined, and the contractility of the heart, hindgut, and oviduct muscles was tested using the video-microscopy technique. Finally, the ultrastructure of the fat body and the midgut was observed using electron microscopy. RESULTS: No lethal effects were noted. Sublethal changes were observed in the content of biomolecules, malformations of organelles, chromatin condensation, and heart and oviduct contractility. The observed effects differed between the tested glycoalkaloids and the extract. CONCLUSIONS: Both the extract and pure GAs have a wide range of effects that may result in impaired development, food intake, and reproduction. Some early effects may be used as bioindicators of stress. The effects of the extract and pure alkaloids suggest that the substances produced by the plant may act additively or synergistically.


Assuntos
Alcaloides/toxicidade , Extratos Vegetais/toxicidade , Solanum nigrum , Tenebrio/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Corpo Adiposo/efeitos dos fármacos , Corpo Adiposo/patologia , Feminino , Frutas , Glicogênio/metabolismo , Coração/efeitos dos fármacos , Coração/fisiologia , Proteínas de Insetos/metabolismo , Intestinos/efeitos dos fármacos , Intestinos/patologia , Intestinos/fisiologia , Larva/efeitos dos fármacos , Larva/fisiologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Oviductos/efeitos dos fármacos , Oviductos/fisiologia , Tenebrio/fisiologia
19.
Microsc Res Tech ; 79(10): 948-958, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27440448

RESUMO

Beet Armyworm, Spodoptera exigua is a herbivorous moth and a serious pest of many economically important plants, which are used as food sources. Because of rigorous standards of food quality, usage of synthetic insecticides in crop protection, against pests, is limited. Solanaceae plant extracts may be a relatively cheap source of efficient natural insecticides that can limit usage of synthetic substances. Their biological activity is not fully known. In particular, ultrastructural studies, using transmission electron microscopy, are not usual. In the present article we describe the effects of sublethal concentrations of tomato and potato leaf extracts against S. exigua. Acute lethal effects were not observed. Both extracts exerted similar effects within midgut and fat body cells. Midgut cells were not significantly altered while fat body cells showed prominent swelling of nuclear envelope and endoplasmic reticulum, vacuolization of mitochondria and fusion of fat droplets. These changes were much more intensive within groups exposed to potato than tomato extracts at highest concentration at least. Light microscopy was used to observe and document developmental alterations of S. exigua exposed to potato and tomato leaf extracts. Potato leaf extracts significantly decreased hatching success and caused morphological malformations of imagoes. Among them, malformations of wings were the most prominent. Interestingly, these effects were not observed within populations exposed to tomato extracts at highest concentration at least.


Assuntos
Inseticidas/farmacologia , Extratos Vegetais/farmacologia , Solanum lycopersicum/química , Solanum tuberosum/química , Spodoptera/efeitos dos fármacos , Spodoptera/ultraestrutura , Animais , Feminino , Larva/efeitos dos fármacos , Masculino , Microscopia Eletrônica de Transmissão
20.
Toxins (Basel) ; 8(3)2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26938561

RESUMO

Only a small percentage of insect species are pests. However, pest species cause significant losses in agricultural and forest crops, and many are vectors of diseases. Currently, many scientists are focused on developing new tools to control insect populations, including secondary plant metabolites, e.g., alkaloids, glycoalkaloids, terpenoids, organic acids and alcohols, which show promise for use in plant protection. These compounds can affect insects at all levels of biological organization, but their action generally disturbs cellular and physiological processes, e.g., by altering redox balance, hormonal regulation, neuronal signalization or reproduction in exposed individuals. Secondary plant metabolites cause toxic effects that can be observed at both lethal and sublethal levels, but the most important effect is repellence. Plants from the Solanaceae family, which contains numerous economically and ecologically important species, produce various substances that affect insects belonging to most orders, particularly herbivorous insects and other pests. Many compounds possess insecticidal properties, but they are also classified as molluscides, acaricides, nematocides, fungicides and bactericides. In this paper, we present data on the sublethal and lethal toxicity caused by pure metabolites and crude extracts obtained from Solanaceae plants. Pure substances as well as water and/or alcohol extracts cause lethal and sublethal effects in insects, which is important from the economical point of view. We discuss the results of our study and their relevance to plant protection and management.


Assuntos
Alcaloides/toxicidade , Agentes de Controle Biológico/toxicidade , Inseticidas/toxicidade , Solanaceae/metabolismo , Alcaloides/metabolismo , Animais , Agentes de Controle Biológico/metabolismo , Humanos , Inseticidas/metabolismo
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