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1.
Anal Methods ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38742423

RESUMO

The non-steroidal anti-inflammatory drug (NSAID) diclofenac (DCF) is an important environmental contaminant occurring in surface waters all over the world, because, after excretion, it is not adequately removed from wastewater in sewage treatment plants. To be able to monitor this pollutant, highly efficient analytical methods are needed, including immunoassays. In a medical research project, monoclonal antibodies against diclofenac and its metabolites had been produced. Based on this monoclonal anti-DCF antibody, a new indirect competitive enzyme-linked immunosorbent assay (ELISA) was developed and applied for environmental samples. The introduction of a spacer between diclofenac and the carrier protein in the coating conjugate led to higher sensitivity. With a test midpoint of 3 µg L-1 and a measurement range of 1-30 µg L-1, the system is not sensitive enough for direct analysis of surface water. However, this assay is quite robust against matrix influences and can be used for wastewater. Without adjustment of the calibration, organic solvents up to 5%, natural organic matter (NOM) up to 10 mg L-1, humic acids up to 2.5 mg L-1, and salt concentrations up to 6 g L-1 NaCl and 75 mg L-1 CaCl2 are tolerated. The antibody is also stable in a pH range from 3 to 12. Cross-reactivity (CR) of 1% or less was determined for the metabolites 4'-hydroxydiclofenac (4'-OH-DCF), 5-hydroxydiclofenac (5-OH-DCF), DCF lactam, and other NSAIDs. Relevant cross-reactivity occurred only with an amide derivative of DCF, 6-aminohexanoic acid (DCF-Ahx), aceclofenac (ACF) and DCF methyl ester (DCF-Me) with 150%, 61% and 44%, respectively. These substances, however, have not been found in samples. Only DCF-acyl glucuronide with a cross-reactivity of 57% is of some relevance. For the first time, photodegradation products were tested for cross-reactivity. With the ELISA based on this antibody, water samples were analysed. In sewage treatment plant effluents, concentrations in the range of 1.9-5.2 µg L-1 were determined directly, with recoveries compared to HPLC-MS/MS averaging 136%. Concentrations in lakes ranged from 3 to 4.4 ng L-1 and were, after pre-concentration, determined with an average recovery of 100%.

2.
Pharmacol Res Perspect ; 11(4): e01109, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37497567

RESUMO

Ethnopharmacology seeks to investigate humankind's use of natural materials, such as plants, fungi, microorganisms, animals, and minerals, for medicinal purposes. In this highly interdisciplinary field, which can be described as a bridge between the natural/medical and socio-cultural sciences, pharmacological, anthropological, and socio-cultural research methods are often applied, along with methods from other branches of science. When entering the field of ethnopharmacology as a newcomer, student, or early career researcher today, the tremendous amount of scientific publications, and even classical books from this field and related scientific disciplines, can be overwhelming. Ethnopharmacology has evolved over the past decades, and new key topics, such as the decolonization of the field, issues on intellectual property and benefit-sharing, species conservation, the preservation of traditional knowledge, the protection of indigenous communities, science outreach, and climate change, have become important and urgent aspects of the field that must not be disregarded by today's ethnopharmacologists. One of the questions of newcomers will be, "Where to begin?" This review article offers a brief (and certainly not comprehensive) introduction to the science of ethnopharmacology, highlighting some of its past most notable achievements and future prospects. In addition, this article provides an example for newcomers to the field of how to address different stages that may be involved in conducting ethnopharmacological field and lab studies, including early-stage drug discovery and community work. The example presented summarizes a series of studies conducted in the remote Greater Mpigi region of Uganda, located in East Africa. Stages of ethnopharmacological research described include ethnobotanical surveying and fieldwork, the pharmacological assessment of activity with diverse targets in the laboratory, and the transfer of results back to indigenous communities, that is, non-financial benefit sharing as a potential best practice example. As a result of this research example, a total of six original research articles have been published on the medicinal application and ethnopharmacology of 16 plant species from the Ugandan study site, offering a large quantity of results. These six publications reflect the multifaceted nature of the interdisciplinary science of ethnopharmacology, which may serve as a reference point and inspiration for newcomers to design and conduct their own independent ethnopharmacological research endeavors at other study sites. Major bottlenecks and solutions are provided, and the current social media channels with educational ethnopharmacological content are briefly introduced.


Assuntos
Plantas Medicinais , Animais , Etnofarmacologia/métodos , Etnobotânica , Inquéritos e Questionários , Projetos de Pesquisa
3.
J Fungi (Basel) ; 9(1)2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36675900

RESUMO

Agents with antifungal activity play a vital role as therapeutics in health care, as do fungicides in agriculture. Effectiveness, toxicological profile, and eco-friendliness are among the properties used to select suitable substances. Furthermore, a steady supply of new agents with different modes of action is required to counter the well-known potential of human and phyto-pathogenic fungi to develop resistance against established antifungals. Here, we use an in vitro growth assay to investigate the activity of the calcineurin inhibitor tacrolimus in combination with the commercial fungicides cyproconazole and hymexazol, as well as with two earlier reported novel {2-(3-R-1H-1,2,4-triazol-5-yl)phenyl}amines, against the fungi Aspergillus niger, Colletotrichum higginsianum, Fusarium oxysporum and the oomycete Phytophthora infestans, which are notoriously harmful in agriculture. When tacrolimus was added in a concentration range from 0.25 to 25 mg/L to the tested antifungals (at a fixed concentration of 25 or 50 mg/L), the inhibitory activities were distinctly enhanced. Molecular docking calculations revealed triazole derivative 5, (2-(3-adamantan-1-yl)-1H-1,2,4-triazol-5-yl)-4-chloroaniline), as a potent inhibitor of chitin deacetylases (CDA) of Aspergillus nidulans and A. niger (AnCDA and AngCDA, respectively), which was stronger than the previously reported polyoxorin D, J075-4187, and chitotriose. The results are discussed in the context of potential synergism and molecular mode of action.

4.
Front Pharmacol ; 12: 678535, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34276369

RESUMO

We investigated the potential antimalarial and toxicological effects of 16 medicinal plants frequently used by traditional healers to treat malaria, fever, and related disorders in the Greater Mpigi region in Uganda. Species studied were Albizia coriaria, Cassine buchananii, Combretum molle, Erythrina abyssinica, Ficus saussureana, Harungana madagascariensis, Leucas calostachys, Microgramma lycopodioides, Morella kandtiana, Plectranthus hadiensis, Securidaca longipedunculata, Sesamum calycinum subsp. angustifolium, Solanum aculeastrum, Toddalia asiatica, Warburgia ugandensis, and Zanthoxylum chalybeum. In addition, the traditional healers indicated that P. hadiensis is used as a ritual plant to boost fertility and prepare young women and teenagers for motherhood in some Ugandan communities where a high incidence of rapidly growing large breast masses in young female patients was observed (not necessarily breast cancer). We present results from various in vitro experiments performed with 56 different plant extracts, namely, 1) an initial assessment of the 16 species regarding their traditional use in the treatment of malaria by identifying promising plant extract candidates using a heme biocrystallization inhibition library screen; 2) follow-up investigations of antiprotozoal effects of the most bioactive crude extracts against chloroquine-resistant P. falciparum K1; 3) a cytotoxicity counterscreen against human MRC-5SV2 lung fibroblasts; 4) a genotoxicity evaluation of the extract library without and with metabolic bioactivation with human S9 liver fraction; and 5) an assessment of the mutagenicity of the ritual plant P. hadiensis. A total of seven extracts from five plant species were selected for antiplasmodial follow-up investigations based on their hemozoin formation inhibition activity in the heme biocrystallization assay. Among other extracts, an ethyl acetate extract of L. calostachys leaves exhibited antiplasmodial activity against P. falciparum K1 (IC50 value: 5.7 µg/ml), which was further characterized with a selectivity index of 2.6 (CC50 value: 14.7 µg/ml). The experiments for assessment of potential procarcinogenic properties of plant extracts via evaluation of in vitro mutagenicity and genotoxicity indicated that few extracts cause mutations. The species T. asiatica showed the most significant genotoxic effects on both bacterial test strains (without metabolic bioactivation at a concentration of 500 µg/plate). However, none of the mutagenic extracts from the experiments without metabolic bioactivation retained their genotoxic activity after metabolic bioactivation of the plant extract library through pre-incubation with human S9 liver fraction. While this study did not show that P. hadiensis has genotoxic properties, it did provide early stage support for the therapeutic use of the medicinal plants from the Greater Mpigi region.

5.
Plants (Basel) ; 10(2)2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33673238

RESUMO

Our study investigates 16 medicinal plants via assessment of inhibition of proinflammatory enzymes such as cyclooxygenases (COX). The plants are used by traditional healers in the Greater Mpigi region in Uganda to treat inflammation and related disorders. We present results of diverse in vitro experiments performed with 76 different plant extracts, namely, (1) selective COX-2 and COX-1 inhibitor screening; (2) 15-LOX inhibition screening; (3) antibacterial resazurin assay against multidrug-resistant Staphylococcus aureus, Listeria innocua, Listeria monocytogenes, and Escherichia coli K12; (4) DPPH assay for antioxidant activity; and (5) determination of the total phenolic content (TPC). Results showed a high correlation between traditional use and pharmacological activity, e.g., extracts of 15 out of the 16 plant species displayed significant selective COX-2 inhibition activity in the PGH2 pathway. The most active COX-2 inhibitors (IC50 < 20 µg/mL) were nine extracts from Leucas calostachys, Solanum aculeastrum, Sesamum calycinum subsp. angustifolium, Plectranthus hadiensis, Morella kandtiana, Zanthoxylum chalybeum, and Warburgia ugandensis. There was no counteractivity between COX-2 and 15-LOX inhibition in these nine extracts. The ethyl acetate extract of Leucas calostachys showed the lowest IC50 value with 0.66 µg/mL (COX-2), as well as the most promising selectivity ratio with 0.1 (COX-2/COX-1). The TPCs and the EC50 values for DPPH radical scavenging activity showed no correlation with COX-2 inhibitory activity. This led to the assumption that the mechanisms of action are most likely not based on scavenging of reactive oxygen species and antioxidant activities. The diethyl ether extract of Harungana madagascariensis stem bark displayed the highest growth inhibition activity against S. aureus (MIC value: 13 µg/mL), L. innocua (MIC value: 40 µg/mL), and L. monocytogenes (MIC value: 150 µg/mL). This study provides further evidence for the therapeutic use of the previously identified plants used medicinally in the Greater Mpigi region.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33510807

RESUMO

In ethnopharmacological research, many field assessment tools exist. Yet, these miss that critical point of how to really determine which species merit the costly lab studies, e.g., evaluation of traditional use via pharmacological assays and isolation of bioactive secondary metabolites. This gap can be filled with the introduction of a new tool for literature assessment: the Degrees of Publication (DoPs). In this study, its application is illustrated through an extensive bibliographic assessment of 16 medicinal plant species that were recently identified in the Greater Mpigi region of Uganda as being frequently used by local traditional healers in the treatment of medical disorders (namely, Albizia coriaria, Cassine buchananii, Combretum molle, Erythrina abyssinica, Ficus saussureana, Harungana madagascariensis, Leucas calostachys, Microgramma lycopodioides, Morella kandtiana, Plectranthus hadiensis, Securidaca longipedunculata, Sesamum calycinum subsp. angustifolium, Solanum aculeastrum, Toddalia asiatica, Warburgia ugandensis, and Zanthoxylum chalybeum). These species are suspected to be understudied, and a thorough bibliographic assessment has not been previously performed. Thus, the objectives of our study were to undertake a comparative assessment of the degree to which each of these plant species has been studied in the past, including evaluation of the quality of the journals where results were published in. The determination of the DoPs enabled successful assessment of the degrees to which each individual plant species has been studied so far, while also taking into account the methodological "research chain of ethnopharmacology" from ethnobotanical studies ("traditional use") to pharmacological assays ("bioactivity") and finally to pharmacognostic research ("structure elucidation"). The significance of a research paper was assessed by determining whether its journal and publishing house were members of the Committee on Publication Ethics (COPE). In total, 634 peer-reviewed publications were reviewed covering the period of 1960-2019, 53.3% of which were published in journals and by publishing houses affiliated with COPE (338 publications). The literature assessment resulted in the identification of understudied plants among the selected species. The majority of plants reviewed have not been sufficiently studied; six species were classified as being highly understudied and three more as being understudied: C. buchananii, F. saussureana, L. calostachys, M. lycopodioides, M. kandtiana, and S. calycinum subsp. angustifolium and A. coriaria, P. hadiensis, and S. aculeastrum, respectively. The newly introduced DoPs are a useful tool for the selection of traditionally used species for future laboratory studies, especially for pharmacological bioassays, isolation procedures, and drug discovery strategies.

7.
Sci Rep ; 10(1): 11935, 2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32686689

RESUMO

Antibiotic resistance poses one of the greatest threats to global health today; conventional drug therapies are becoming increasingly inefficacious and limited. We identified 16 medicinal plant species used by traditional healers for the treatment of infectious and inflammatory diseases in the Greater Mpigi region of Uganda. Extracts were evaluated for their ability to inhibit growth of clinical isolates of multidrug-resistant ESKAPE pathogens. Extracts were also screened for quorum quenching activity against S. aureus, including direct protein output assessment (δ-toxin), and cytotoxicity against human keratinocytes (HaCaT). Putative matches of compounds were elucidated via LC-FTMS for the best-performing extracts. These were extracts of Zanthoxylum chalybeum (Staphylococcus aureus: MIC: 16 µg/mL; Enterococcus faecium: MIC: 32 µg/mL) and Harungana madagascariensis (S. aureus: MIC: 32 µg/mL; E. faecium: MIC: 32 µg/mL) stem bark. Extracts of Solanum aculeastrum root bark and Sesamum calycinum subsp. angustifolium leaves exhibited strong quorum sensing inhibition activity against all S. aureus accessory gene regulator (agr) alleles in absence of growth inhibition (IC50 values: 1-64 µg/mL). The study provided scientific evidence for the potential therapeutic efficacy of these medicinal plants in the Greater Mpigi region used for infections and wounds, with 13 out of 16 species tested being validated with in vitro studies.


Assuntos
Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Anti-Infecciosos/química , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/microbiologia , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida , Relação Dose-Resposta a Droga , Humanos , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Espectrometria de Massas , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Percepção de Quorum/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Uganda
8.
J Ethnopharmacol ; 256: 112742, 2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32224196

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: This study provides the first report on selected traditional medicinal plant use, including parts used and methods of preparation, in the Greater Mpigi region of Uganda. This data supports the conservation of local traditional ecological knowledge and will facilitate future drug discovery research. AIM OF THE STUDY: Our study aimed to conserve culturally and scientifically-valuable medical knowledge of 16 plant species traditionally used in the Greater Mpigi region in Uganda, namely Albizia coriaria, Cassine buchananii, Combretum molle, Erythrina abyssinica, Ficus saussureana, Harungana madagascariensis, Leucas calostachys, Microgramma lycopodioides, Morella kandtiana, Plectranthus hadiensis, Securidaca longipedunculata, Sesamum calycinum subsp. angustifolium, Solanum aculeastrum, Toddalia asiatica, Warburgia ugandensis and Zanthoxylum chalybeum. An additional objective of the study was an ethnological investigation of the socio-cultural background and medical understanding of diseases treated by traditional healers in the study area. MATERIALS AND METHODS: A pilot survey in the study area revealed that 16 plant species were frequently used in treatment of a variety of medical disorders. In order to obtain more complete information, we conducted a broader ethnobotanical survey using structured interviews with 39 traditional healers from 29 villages, specifically asking about the traditional uses of these 16 medicinal species. RESULTS: Results of the survey confirmed a high level of traditional use of these species in the Greater Mpigi region. In addition, various other traditional uses and methods of preparation were recorded, most of them for the first time. In total, 75 different medical disorders treated with the plants were documented. CONCLUSIONS: Conservation of traditional knowledge for future generations is vital, as loss has already been recorded due to multiple causes. The need for novel and more effective drugs derived from natural products is more important than ever, making future studies on herbal remedies both justified and urgently required. The traditional healers surveyed in this project also have expectations of the research - they would like to be updated about any resulting studies into the pharmacological efficacy of medicinal plants so that the research findings can inform their confidence in each herbal remedy.


Assuntos
Preparações de Plantas/uso terapêutico , Plantas Medicinais/química , Adulto , Idoso , Etnobotânica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fitoterapia/métodos , População Rural , Inquéritos e Questionários , Uganda , Adulto Jovem
9.
Arch Pharm (Weinheim) ; 352(10): e1900092, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31463959

RESUMO

Due to their high specificity and efficacy, triazoles have become versatile antifungals to treat fungal infections in human healthcare and to control phytopathogenic fungi in agriculture. However, azole resistance is an emerging problem affecting human health as well as food security. Here we describe the synthesis of 10 novel {2-(3-R-1H-1,2,4-triazol-5-yl)phenyl}amines. Their structure was ascertained by liquid chromatography-mass spectrometry, 1 H and 13 C NMR, and elemental analysis data. Applying an in vitro growth assay, these triazoles show moderate to significant antifungal activity against the opportunistic pathogen Aspergillus niger, 12 fungi (Fusarium oxysporum, Fusarium fujikuroi, Colletotrichum higginsianum, Gaeumannomyces graminis, Colletotrichum coccodes, Claviceps purpurea, Alternaria alternata, Mucor indicus, Fusarium graminearum, Verticillium lecanii, Botrytis cinerea, Penicillium digitatum) and three oomycetes (Phytophtora infestans GL-1, P. infestans 4/91; R+ and 4/91; R-) in the concentration range from 1 to 50 µg/ml (0.003-2.1 µM). Frontier molecular orbital energies were determined to predict their genotoxic potential. Molecular docking calculations taking into account six common fungal enzymes point to 14α-demethylase (CYP51) and N-myristoyltransferase as the most probable fungal targets. With respect to effectiveness, structure-activity calculations revealed the strong enhancing impact of adamantyl residues. The shown nonmutagenicity in the Salmonella reverse-mutagenicity assay and no violations of drug-likeness parameters suggest the good bioavailability and attractive ecotoxicological profile of the studied triazoles.


Assuntos
Antifúngicos/síntese química , Desenho de Fármacos , Fungos Mitospóricos/efeitos dos fármacos , Triazóis/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Testes de Sensibilidade Microbiana , Fungos Mitospóricos/crescimento & desenvolvimento , Simulação de Acoplamento Molecular , Estrutura Molecular , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/genética , Relação Estrutura-Atividade , Triazóis/química , Triazóis/farmacologia , Triazóis/toxicidade
10.
Arch Pharm (Weinheim) ; 352(2): e1800275, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30589110

RESUMO

Nine novel acyl thioureas were synthesized. Their identities and purities were confirmed by LC-MS spectra; each structure was elucidated by elemental analysis, IR, 1 Н and 13 C NMR spectra. Applying an in vitro screening of their antifungal potential, three substances (3, 5, and 6) could be selected as showing high activity against 11 fungi and 3 Phytophthora strains of phytopathogenic significance. Analysis of gene toxicity with the Salmonella reverse mutagenicity test, as an assessment of drug likeness, lipophilicity, and calculations of frontier molecular orbitals assign a low toxicity profile to these compounds. Molecular docking studies point to 14α-demethylase (CYP51) and N-myristoyltransferase (NMT) as possible fungal targets for growth inhibition. The findings are discussed with respect to structure-activity relationship (SAR).


Assuntos
Antifúngicos/farmacologia , Simulação de Acoplamento Molecular , Tioureia/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Cromatografia Líquida/métodos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas/métodos , Testes de Mutagenicidade , Salmonella/efeitos dos fármacos , Salmonella/genética , Relação Estrutura-Atividade , Tioureia/análogos & derivados , Tioureia/síntese química
11.
Acta Chim Slov ; 66(4): 784-791, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34057481

RESUMO

Tacrolimus (FK506) is an immunosuppressant drug widely used to avoid organ rejection in transplant patients. It has a profound influence on the cellular stress response by interfering with the calmodulin-calcineurin signaling pathway. In this context FK506 also became a valuable antifungal drug in medical care. Here it is shown in vitro that tacrolimus has a potent growth inhibition activity against 11 fungi and 3 oomycetes of agricultural importance. The significance of this finding is discussed with respect to crop protection. The in silico molecular docking to 6 major antifungal enzymes determined UDP-N-acetylmuramoyl-L-alanine: D-glutamate ligase (MurD) as the main target by the best affinity score.

12.
J Chromatogr A ; 1538: 112-116, 2018 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-29397981

RESUMO

A frequently studied environmental contaminant is the active substance diclofenac, which is removed insufficiently in sewage treatment plants. Since its inclusion in the watch list of the EU Water Framework Directive, the concentrations in surface waters will be determined throughout Europe. For this, still, more precise analytical methods are needed. As a reference, HPLC-MS is frequently employed. One of the major metabolites is 4'-hydroxydiclofenac (4'-OH-DCF). Also, diclofenac lactam is important for assessing degradation and transformation. Aceclofenac (ACF), the glycolic acid ester of diclofenac is used as a drug, too, and could potentially be cleaved to yield diclofenac again. In various sewage treatment plant influent samples, diclofenac, 4'-OH-DCF, DCF lactam and ACF could be determined with detection limits of 3 µg/L, 0.2 µg/L, 0.17 µg/L and 10 ng/L, respectively.


Assuntos
Cromatografia Líquida , Diclofenaco/análise , Monitoramento Ambiental/métodos , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise , Água/química , Diclofenaco/análogos & derivados , Europa (Continente) , Limite de Detecção , Esgotos/química
13.
Acta Chim Slov ; 65(4): 836-841, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33562930

RESUMO

Antifungal activity of suberic acid monomethyl ester (monomethyl suberate) was investigated in a growth inhibition assay comprising of 11 different fungi and 3 Phytophthora oomycetes strains relevant in agriculture. In comparison to standard antifungal hymexazol, monomethyl suberate showed moderate antifungal effects at a concentration range of 100-300 µg/mL. Alternaria alternata, Fusarium equiseti, Fusarium fujikuroi and Phytophtora infestans GL-1 were the most sensitive fungi showing inhibition rates up to 100 %. Physico-chemical descriptors of monomethyl suberate revealed its low toxicity profile. Molecular docking analysis comprising several known antifungal targets points to the N-myristoyltransferase as the most probable site of interaction.

14.
Anal Biochem ; 543: 90-96, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29233681

RESUMO

Diisononylcyclohexane-1,2-dicarboxylate (DINCH) and di-2-ethylhexyl terephthalate (DEHT), two of the most important substitutes for phthalate plasticizers, are used for a wide range of applications. Consequently, an increasing occurrence in urine and environmental samples is reported. Reliable and fast analytical methods for the quantification of these plasticizers are needed. So far, mainly GC-MS or LC-MS methods are used. We aimed to develop the first antibodies and immunoassays allowing for high-throughput analysis of samples. We designed two DINCH hapten structures and one DEHT hapten structure and employed hapten-protein conjugates for the immunization of rabbits. Sensitive competitive enzyme-linked immunosorbent assays (ELISAs) against each hapten using the produced polyclonal antibodies were established. Yet, binding of DINCH to the respective antibodies was not observed in neither direct nor indirect assay formats, even when using protein conjugates with the heterologous haptens and different carrier proteins in the indirect format. The use of surfactants and solvents in the sample buffer did not result in recognition of the plasticizers. Also, no binding of DEHT in ELISA employing the respective antibodies was detected. We speculate that the production of antibodies against these highly hydrophobic molecules is not possible via our route, however a different hapten design could overcome this obstacle.


Assuntos
Anticorpos/química , Ácidos Cicloexanocarboxílicos/química , Ácidos Dicarboxílicos/química , Ácidos Ftálicos/química , Plastificantes/química , Animais , Anticorpos/imunologia , Ácidos Cicloexanocarboxílicos/imunologia , Ácidos Dicarboxílicos/imunologia , Ensaio de Imunoadsorção Enzimática , Ensaios de Triagem em Larga Escala , Interações Hidrofóbicas e Hidrofílicas , Ácidos Ftálicos/imunologia , Coelhos
15.
J Environ Manage ; 193: 92-97, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28192740

RESUMO

Carbamazepine is an antiepileptic drug that can be used as a marker for the cleaning efficiency of wastewater treatment plants. Here, we present the optimization of a fast and easy on-site measurement system based on fluorescence polarization immunoassay and the successful application to wastewater. A new monoclonal highly specific anti-carbamazepine antibody was applied. The automated assay procedure takes 16 min and does not require sample preparation besides filtration. The recovery rates for carbamazepine in wastewater samples were between 60.8 and 104% with good intra- and inter-assay coefficients of variations (less than 15 and 10%, respectively). This automated assay enables for the on-site measurement of carbamazepine in wastewater treatment plants.


Assuntos
Carbamazepina , Imunoensaio de Fluorescência por Polarização , Anticonvulsivantes , Bioensaio , Águas Residuárias
16.
J Environ Manage ; 182: 612-619, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27544648

RESUMO

Bile acids are promising chemical markers to assess the pollution of water samples with fecal material. This study describes the optimization and validation of a direct competitive enzyme-linked immunosorbent assay for the bile acid isolithocholic acid (ILA). The quantification range of the optimized assay was between 0.09 and 15 µg/L. The assay was applied to environmental water samples. Most studies until now were focused on bile acid fractions in the particulate phase of water samples. In order to avoid tedious sample preparation, we undertook to evaluate the dynamics and significance of ILA levels in the aqueous phase. Very low concentrations in tap and surface water samples made a pre-concentration step necessary for this matrix as well as for wastewater treatment plant (WWTP) effluent. Mean recoveries for spiked water samples were between 97% and 109% for tap water and WWTP influent samples and between 102% and 136% for WWTP effluent samples. 90th percentiles of intra-plate and inter-plate coefficients of variation were below 10% for influents and below 20% for effluents and surface water. ILA concentrations were quantified in the range of 33-72 µg/L in influent, 21-49 ng/L in effluent and 18-48 ng/L in surface water samples. During wastewater treatment the ILA levels were reduced by more than 99%. ILA concentrations of influents determined by ELISA and LC-MS/MS were in good agreement. However, findings in LC-ELISA experiments suggest that the true ILA levels in concentrated samples are lower due to interfering effects of matrix compounds and/or cross-reactants. Yet, the ELISA will be a valuable tool for the performance check and comparison of WWTPs and the localization of fecal matter input into surface waters.


Assuntos
Monitoramento Ambiental/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Ácido Litocólico/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Ácidos e Sais Biliares/química , Calibragem , Cromatografia Líquida , Fezes , Espectrometria de Massas em Tandem , Eliminação de Resíduos Líquidos
17.
Chirality ; 28(9): 623-7, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27496202

RESUMO

In the current study, we present a green toolbox to produce ecological compounds like lactone moiety. Rhodococcus erythropolis DSM 44534 cells have been used to oxidize both decane-1,4-diol () and decane-1,5-diol () into the corresponding γ- () and δ-decalactones () with yield of 80% and enantiomeric excess (ee) = 75% and ee = 90%, respectively. Among oxidation of meso diols, (-)-(1S,5R)-cis-3-oxabicyclo[4.3.0]non-7-en-2-one (5a) with 56% yield and ee = 76% as well as (-)-(2R,3S)-cis-endo-3-oxabicyclo[2.2.1]dec-7-en-2-one (6a) with 100% yield and ee = 90% were formed. It is worth mentioning that R. erythropolis DSM 44534 grew in a mineral medium containing ethanol as the sole source of energy and carbon Chirality 28:623-627, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Química Verde/métodos , Lactonas/química , Rhodococcus/química , Biotransformação , Catálise , Rhodococcus/metabolismo , Estereoisomerismo
18.
J Agric Food Chem ; 64(13): 2737-45, 2016 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-26996287

RESUMO

Absorption of hop volatiles by crown cork liner polymers and can coatings was investigated in beer during storage. All hop volatiles measured were prone to migrate into the closures, and the absorption kinetics was demonstrated to fit Fick's second law of diffusion well for a plane sheet. The extent and rate of diffusion were significantly dissimilar and were greatly dependent upon the nature of the volatile. Diffusion coefficients ranged from 1.32 × 10(-5) cm(2)/day (limonene) to 0.26 × 10(-5) cm(2)/day (α-humulene). The maximum amounts absorbed into the material at equilibrium were in the following order: limonene > α-humulene > trans-caryophyllene > myrcene ≫ linalool > α-terpineol > geraniol. With the application of low-density polyethylene (LDPE) liners with oxygen-scavenging functionality, oxygen-barrier liners made up from high-density polyethylene (HDPE) or liner polymers from a different manufacturer had no significant effect on the composition of hop volatiles in beers after prolonged storage of 55 days; however, significantly higher amounts of myrcene and limonene were found in the oxygen-barrier-type crown cork, while all other closures behaved similarly. Can coatings were demonstrated to absorb hop volatiles in a similar pattern as crown corks but to a lesser extent. Consequently, significantly higher percentages of myrcene were found in the beers.


Assuntos
Humulus/química , Polímeros/química , Terpenos/análise , Monoterpenos Acíclicos , Alcenos , Cerveja/análise , Monoterpenos Cicloexânicos , Cicloexenos , Cromatografia Gasosa-Espectrometria de Massas , Limoneno , Sesquiterpenos Monocíclicos , Monoterpenos , Sesquiterpenos Policíclicos , Polietileno , Sesquiterpenos
19.
Int Orthop ; 40(5): 1039-47, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26907873

RESUMO

PURPOSE: Surgical procedures to prevent osteomyelitis after trauma can be supported by local application of antibiotics. This in-vitro study investigated the release and impact of antibiotics from implant coatings against bacteria associated with combat-related osteomyelitis. METHODS: K-wires were coated with poly(D,L-lactide) and ciprofloxacin, gentamicin, colistin, daptomycin or cefoxitin in different concentrations. The release was quantified and antimicrobial activity tested for different gram-positive or gram-negative bacteria, alone and in combination. To exclude toxic effects, primary osteoblast-like cells were exposed to antibiotic coating concentrations. RESULTS: All antibiotics alone and in combination showed an initial burst release with dose dependent antimicrobial activity and no negative effects on osteoblast-like cells, except for cefoxitin. CONCLUSIONS: Implant coatings can be customized with single or double antibiotic coatings to effectively fight different bacteria and also mixed infections in the treatment of a combat-acquired osteomyelitis. However, optimal drug load and degradation behaviour of individual antibiotics have to be considered.


Assuntos
Antibacterianos/administração & dosagem , Fios Ortopédicos , Osteomielite/tratamento farmacológico , Próteses e Implantes , Lesões Relacionadas à Guerra/tratamento farmacológico , Bactérias , Técnicas de Cultura de Células , Humanos , Técnicas In Vitro , Lesões Relacionadas à Guerra/microbiologia
20.
Toxicon ; 105: 10-2, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26335359

RESUMO

Zearalenone and its cis-isomer, cis-zearalenone, are nonsteroidal mycotoxins that elicit an estrogenic response upon binding to the estrogen receptor. This study compares the estrogenicity of eleven congeners including novel metabolites as 15-OH-zearalenone, zearalenone-14-sulfate, α-cis-zearalenol and ß-cis-zearalenol using the E-Screen assay. Overall, a change in the configuration from trans to cis retains significant estrogenic activity. In contrast, alterations of the aromatic moiety including hydroxylation and sulfation showed a markedly decreased estrogenicity when compared to zearalenone.


Assuntos
Estrogênios/metabolismo , Zearalenona/metabolismo , Linhagem Celular Tumoral , Humanos
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