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1.
Environ Microbiol ; 24(11): 5105-5122, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35799498

RESUMO

Thiabendazole (TBZ), is a persistent fungicide/anthelminthic and a serious environmental threat. We previously enriched a TBZ-degrading bacterial consortium and provided first evidence for a Sphingomonas involvement in TBZ transformation. Here, using a multi-omic approach combined with DNA-stable isotope probing (SIP) we verified the key degrading role of Sphingomonas and identify potential microbial interactions governing consortium functioning. SIP and amplicon sequencing analysis of the heavy and light DNA fraction of cultures grown on 13 C-labelled versus 12 C-TBZ showed that 66% of the 13 C-labelled TBZ was assimilated by Sphingomonas. Metagenomic analysis retrieved 18 metagenome-assembled genomes with the dominant belonging to Sphingomonas, Sinobacteriaceae, Bradyrhizobium, Filimonas and Hydrogenophaga. Meta-transcriptomics/-proteomics and non-target mass spectrometry suggested TBZ transformation by Sphingomonas via initial cleavage by a carbazole dioxygenase (car) to thiazole-4-carboxamidine (terminal compound) and catechol or a cleaved benzyl ring derivative, further transformed through an ortho-cleavage (cat) pathway. Microbial co-occurrence and gene expression networks suggested strong interactions between Sphingomonas and a Hydrogenophaga. The latter activated its cobalamin biosynthetic pathway and Sphingomonas its cobalamin salvage pathway to satisfy its B12 auxotrophy. Our findings indicate microbial interactions aligning with the 'black queen hypothesis' where Sphingomonas (detoxifier, B12 recipient) and Hydrogenophaga (B12 producer, enjoying detoxification) act as both helpers and beneficiaries.


Assuntos
Dioxigenases , Fungicidas Industriais , Sphingomonas , Sphingomonas/genética , Sphingomonas/metabolismo , Tiabendazol/metabolismo , Fungicidas Industriais/metabolismo , Dioxigenases/metabolismo , Biodegradação Ambiental , Bactérias/genética , Bactérias/metabolismo , Carbazóis/metabolismo , Vitamina B 12/metabolismo
2.
J Cross Cult Gerontol ; 31(2): 129-41, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26883764

RESUMO

To find associations of age, sex, and education with neuropsychological test performance in cognitively normal Spanish-speaking Costa Rican nonagenarians with little education; to provide norms; and to compare their performance with similar Puerto Ricans. For 95 Costa Ricans (90-102 years old, 0-6 years of education), multiple regression assessed associations with demographics of performance on six neuropsychological tests. Analyses of covariance compared them with 23 Puerto Ricans (90-99 years old). Younger age and being female-but not education-were associated with better performance on some neuropsychological tests, in particular episodic memory. The Puerto Ricans performed better on learning and memory tasks. In cognitively intact Spanish-speaking nonagenarians with little or no education, education did not affect test performance. Additional studies of the effect of education on cognitive performance are warranted in other samples with extremely low education or old age. National differences in performance highlight the importance of group-specific norms.


Assuntos
Envelhecimento/psicologia , Cognição/fisiologia , Comparação Transcultural , Escolaridade , Hispânico ou Latino/psicologia , Hispânico ou Latino/estatística & dados numéricos , Testes Neuropsicológicos/estatística & dados numéricos , Fatores Etários , Idoso de 80 Anos ou mais , Costa Rica , Educação , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Porto Rico , Fatores Sexuais
3.
J Sep Sci ; 37(6): 665-74, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24532456

RESUMO

A method based on QuEChERS (quick, easy, cheap, effective, rugged, and safe) has been developed and validated for the determination and quantification of more than 140 pesticides in nutraceutical products obtained from green tea (Camellia sinensis). Extraction was performed with acidified acetonitrile (acetic acid 1%, v/v) and a clean-up step using primary secondary amine (50 mg), graphitized black carbon (100 mg) and magnesium sulfate (200 mg) was needed. Pesticide determination was achieved utilizing GC coupled to triple quadrupole MS/MS using the selective-reaction monitoring mode. The total run time was 23 min. Pesticides were quantified using matrix-matched calibration. Recoveries ranged from 70 to 120% and relative SD was lower than 25% at 10, 50, and 100 µg/kg. LOQs were lower than 10 µg/kg. 148 pesticides were validated. The validated method was applied to commercial nutraceutical products, detecting 4,4-dichlorobenzophenone (28 µg/kg), o,p'-dicofol (38 µg/kg) and p,p-dicofol (44 µg/kg) in a few samples.


Assuntos
Camellia sinensis/química , Suplementos Nutricionais/análise , Contaminação de Alimentos/análise , Praguicidas/análise , Cromatografia Gasosa-Espectrometria de Massas
4.
J Sep Sci ; 37(1-2): 69-76, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24302622

RESUMO

The analysis of brominated flame retardants, such as polybrominated diphenyl ethers (PBDEs), has received increased interest because of their toxicity and ubiquity. According to European Union Directive 2008/105/EC, the development of highly sensitive and selective methods capable of determining PBDEs at low concentration levels (<0.5 ng/L) is necessary. In this work, an SPE method was developed for the analysis of the six PBDEs (BDE-28, BDE-47, BDE-99, BDE-100, BDE-153, BDE-154) specified by the aforementioned directive in surface waters. The analyses were performed by GC coupled to magnetic sector high-resolution MS. The conditions were also optimized to detect the target compounds in water samples at concentrations below the environmental quality standards established by European legislation. The validated method provided adequate linearity (determination coefficient, R(2) ≥ 0.9960), recovery (101-120%, except for BDE-47 at 5 ng/L, 127%), and precision values (RSD < 20%) at two fortification levels (0.2 and 5 ng/L). The method showed LODs and LOQs ranging from 0.02 to 0.05 and from 0.05 to 0.1 ng/L, respectively. The method was applied in surface water samples, allowing the determination of these compounds at the limits established by current legislation.


Assuntos
Monitoramento Ambiental/métodos , Retardadores de Chama/análise , Água Doce/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Éteres Difenil Halogenados/análise , Poluentes Químicos da Água/análise , Poluição Química da Água/legislação & jurisprudência , Monitoramento Ambiental/legislação & jurisprudência , União Europeia , Sensibilidade e Especificidade , Poluição Química da Água/análise
5.
J AOAC Int ; 97(4): 1027-33, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25145133

RESUMO

A method for the determination of 14 biopesticides and piperonyl butoxide (PBO), often applied in organic farming, in vegetables and fruits has been developed. Extraction was performed using the Quick, Easy, Cheap, Effective, Rugged, and Safe method, and the determination was carried out by ultra-performance LC/MS/MS in 9 min. Several different food commodities were evaluated as representative matrixes, namely, cucumber, tomato, pepper (high water content), and strawberry and orange (high acid and water content). Biopesticides were quantified using matrix-matched calibration, and the optimized method was validated at three concentration levels, i.e., 10, 50, and 100 microg/kg, for all the compounds, yielding recoveries in the range 70-112%, 71-112%, and 70-109%, respectively, with RSDs <28%. LOQs were <3 microg/kg for all biopesticides. The validated procedure was applied to the analysis of vegetables and fruits, including products from organic farming; PBO was detected in one sample at 8 microg/kg.


Assuntos
Frutas/química , Praguicidas/análise , Extração em Fase Sólida , Verduras/química , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas em Tandem
6.
Int J Food Sci Nutr ; 65(7): 791-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24828257

RESUMO

Phytochemicals content, including several families such as phenolic acids, isoflavones, flavones, flavonols, isothiocyanates, and glucosinolates, was determined in pre-cooked convenience vegetables by ultra high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS). It was observed that there is not a common behavior of the individual concentration of phytochemicals during the lifetime and cooking of the matrix, and compounds change their concentration without a specific trend. It was observed that neither lifetime nor cooking process have significant effects on the total content of phytochemicals except in broccoli, although some changes in the individual content of the target compounds were observed, suggesting that interconversion processes could be performed during the lifetime and/or cooking process of the product.


Assuntos
Culinária , Análise de Alimentos/métodos , Compostos Fitoquímicos , Verduras/química , Armazenamento de Alimentos , Fatores de Tempo
7.
Anal Bioanal Chem ; 405(20): 6543-53, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23712649

RESUMO

A fast and generic method has been developed for the simultaneous monitoring of >250 pesticides and veterinary drugs (VDs) in animal feed. A 'dilute-and-shoot' extraction with water and acetonitrile (1% formic acid) followed by a clean-up step with Florisil cartridges was applied. The extracts were analysed by ultra-high performance liquid chromatography coupled to hybrid analyser quadrupole-time-of-flight mass spectrometry using both positive and negative electrospray ionisation. The detection of the residues was accomplished by retention time and accurate mass using an in-house database. The identification of the detected compounds was carried out by searching of fragment ions for each compound and isotopic pattern. The optimised method was validated and recoveries ranged from 60% to 120% at three concentrations (10, 50 and 100 µg kg(-1)) for 30%, 68% and 80% of compounds, respectively, included in the database (364) in chicken feed. Document SANCO 12495/2011 and Directive 2002/657/CE were used as guidelines for method validation. Intra-day and inter-day precisions, expressed as relative standard deviations, were lower than 20% for more than 90% of compounds. The limits of quantification ranged from 4 to 200 µg kg(-1) for most analytes, which are sufficient to verify compliance of products with legal tolerances. The applicability of the procedure was further tested on different types of feed (chicken, hen, rabbit and horse feed), evaluating recoveries and repeatability. Finally, the method was applied to the analysis of 18 feed samples, detecting some VDs (sulfadiazine, trimethoprim, robenidin and monensin Na) and only one pesticide (chlorpyrifos).


Assuntos
Ração Animal/análise , Cromatografia Líquida/métodos , Resíduos de Drogas/química , Resíduos de Praguicidas/química , Praguicidas/química , Drogas Veterinárias/química , Espectrometria de Massas/métodos , Reprodutibilidade dos Testes
8.
Crit Rev Oncol Hematol ; 181: 103890, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36462594

RESUMO

The Breast Cancer Revealed initiative was designed and conducted to know the status of breast cancer at each point of breast cancer care, through i) prevention, ii) detection, iii) diagnosis, iv) treatment, and iv) the capacity of our health systems. The expert panel from 11 Latin American countries identified several strategies and proposed high impact priorities, including implementation of prevention policies, improve primary healthcare capacity for breast cancer screening, have adequate infrastructure to make effective and timely diagnoses, have a multidisciplinary team in the treatment process, access to a variety of treatments for all types of patients, have a coordinated and articulated system from primary care to specialized hospital. In a region with limited resources, prioritization in high-impact strategies for breast cancer control could lead to improved clinical outcomes and quality of life for our patients.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/terapia , América Latina/epidemiologia , Qualidade de Vida , Atenção à Saúde , Detecção Precoce de Câncer
9.
Rapid Commun Mass Spectrom ; 26(9): 1091-9, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22467459

RESUMO

RATIONALE: A study of pesticide transformation products (TPs) was carried out in soils of agricultural areas working under integrated pest management programs (IPMs). Bupirimate and cyromazine were the pesticides detected in soils after an initial pre-screening. The aim of this work was the identification of relevant TPs of these two pesticides. METHODS: Soil samples were extracted by pressurized liquid extraction (PLE), using a mixture of ethyl acetate/methanol (3:1, v/v), and analyzed by ultra-high-pressure liquid chromatography coupled to hybrid quadrupole-time-of-flight mass spectrometry (UHPLC-QTOF-MS). For confirmation purposes, tandem mass spectrometry (MS(2) ) experiments were carried out using QTOF-MS, obtaining specific fragment structures of the pesticides and their degradates. RESULTS: Retention times and exact masses of the protonated molecules were used for the identification of the pesticides bupirimate (m/z 317.1642) and cyromazine (m/z 167.1040) and their respective TPs, namely ethirimol (m/z 210.1601) and melamine (m/z 127.0727). A novel strategy using pseudo-MS(3) experiments was developed to confirm the structure of bupirimate TP (ethirimol). This strategy consists of generating the particular TP in the ion source, via collision-induced fragmentation, and then performing MS/MS to the fragment ion formed in-source. CONCLUSIONS: Ethirimol and melamine were identified as degradation products of bupirimate and cyromazine, respectively. The study was applied to the analysis of 15 agricultural soil samples finding bupirimate and ethirimol in seven samples, cyromazine in one sample and melamine in four samples.

10.
J Environ Monit ; 14(4): 1182-9, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22370656

RESUMO

A comprehensive survey of the occurrence and fate of pesticides and organic contaminants in soils from an intensive agricultural area devoted to horticultural production in plastic-based greenhouses has been performed to determine if the operation under integrated pest management practices has contributed to reduce the levels of these compounds. Almería province (south-eastern Spain) was selected for the case study. 38 agricultural soil samples (each sample corresponds to an independent private greenhouse) of areas working under integrated pest management (IPM) programs have been analyzed in order to evaluate their contamination fate. Sampling was designed to cover an area of about 400 km(2). Pesticides, polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), phenolic compounds and di-(2-ethylhexyl)phthalate (DEHP) were monitored. The obtained results were compared to other studies reported in Spain and Europe. Among relevant persistent pesticides, DDTs and endosulfans were mainly found and the results indicated historical application, although recent application of endosulfan was rarely detected. PAHs were also found but to a lesser extent and derived from pyrogenic sources. DEHP levels were considerably higher in comparison to the other monitored analytes. The evaluation revealed that despite the use of IPM programs, pesticide and organic contaminants are still being detected in this type of agricultural soil, although at relatively low concentration levels. In general, the contamination rate was similar or lower in comparison to other agricultural areas from nearby regions or countries. However, further monitoring studies should be carried out to establish the possible reduction in contamination by the selected compounds.


Assuntos
Agricultura/estatística & dados numéricos , Praguicidas/análise , Poluentes do Solo/análise , DDT/análise , Dietilexilftalato/análise , Endossulfano/análise , Monitoramento Ambiental , Compostos Orgânicos/análise , Fenóis/análise , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Solo/química , Espanha
11.
Sci Total Environ ; 819: 153063, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35031361

RESUMO

The knowledge about the interaction of nanoplastics with other aquatic pollutants and their combined effects on biota is very scarce. In this work, we studied the interaction between polystyrene nanoplastics (PS NPs) (30 nm) and the micropollutants in a biologically treated wastewater effluent (WW). The capacity of PS NPs to sorb micropollutants was studied as well as their single and combined toxicity towards three freshwater organisms: the recombinant bioluminescent cyanobacterium, Anabaena sp. PCC 7120 CPB4337; the duckweed, Spirodela polyrhiza and the cladoceran, Daphnia magna. The endpoints were the inhibition of bioluminescence, the growth inhibition of the aquatic plant and the immobilization of D. magna after 24, 72 and 48 h of exposure, respectively. Combination Index (CI)-isobologram method was used to quantify mixture toxicity and the nature of interactions. PS NPs sorbed a variety of chemicals present in WW as micropollutants in a range of tens of ng/L to µg/L. It was found that those pollutants with positive charge were the main ones retained onto PS NPs, which was attributed to the electrostatic interaction with the negatively charged PS NPs. Regarding the toxicological effects, single exposure to PS NPs affected the three tested organisms. However, single exposure to WW only had a negative impact on the cyanobacterium and S. polyrhiza with no observed toxicity to D. magna. Regarding PS NPs-WW combined exposure, a reduction of toxicity in comparison with single exposure was observed probably due to the sorption of micropollutants onto PS NPs, which resulted in lower bioavailability of the micropollutants. In addition, the formation of PS NPs-WW heteroaggregates was observed which could result in lower bioavailability of PS NPs and sorbed micropollutants, thus lowering toxicity. This study represents a near-realistic scenario approach to the potential sorption of wastewater pollutants onto nanoplastics that could alter the toxicological effect on the biota.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Microplásticos , Nanopartículas/toxicidade , Poliestirenos/química , Poliestirenos/toxicidade , Águas Residuárias , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade
12.
Anal Bioanal Chem ; 400(10): 3537-46, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21537915

RESUMO

A rapid and simple methodology based on purge and trap with gas-chromatography coupled to triple quadrupole mass spectrometry has been developed for the analysis of 19 volatile organic compounds (VOCs) in wastewater (WW) effluents from four different treatments. The determination was carried out in the raw WW effluents, which were not submitted to any pre-treatment (e.g., filtration). A matrix effect study was also performed, concluding that solvent calibration was adequate to quantify VOCs in WW effluent samples containing a variety of suspended particulate matter. Adequate validation parameters were obtained with recovery values in the range 73-124% and precision values lower than 24%. Limits of quantification were established at 0.1 µg L(-1) for all VOCs. The proposed method was applied to the analysis of WW samples, detecting chloroform and toluene at concentrations ranging from 0.1 to 4.80 µg L(-1).


Assuntos
Compostos Orgânicos Voláteis/análise , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise , Calibragem , Cromatografia Gasosa-Espectrometria de Massas/métodos , Limite de Detecção , Métodos , Solventes/análise
13.
Sci Total Environ ; 755(Pt 2): 142624, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33045600

RESUMO

This work proposes the evaluation of an aluminized surface on the bottom of open reactors to perform a photo-Fenton process, at circumneutral pH (using Fe III-Ethylenediamine-N,N'-disuccinic acid complex), for elimination of micropollutants (MPs) in real effluents from municipal wastewater treatment plants (EMWWTP). Firstly, the strategy was to initially investigate the real EMWWTP spiked with several MPs (acetaminophen, diclofenac, carbamazepine, caffeine, trimethoprim and sulfamethoxazole) with 20 and 100 µg L-1 in a laboratory scale (evaluated by HPLC-UV) using a solar simulator. Finally, the removal of all MCs present in the real EMWWTP was monitored (evaluated by HPLC-MS) in a pilot-scale (90 L) in a raceway pond reactor (RPR). The treatment time required for degradation above 80% for the investigated MPs was over 30 min, and the predominant effect could be mainly associated with organics present in the real EMWWTP due to the light attenuation and scavenging of radical species. Moreover, the results confirmed that chloride and sulfate would most likely equally not affect the process. The use of an aluminized surface on the bottom of RPRs has been confirmed as a suitable option to improve the photo-Fenton reaction, enabling the use of lower doses of iron. Up to 60 different MPs found in EMWWTP have been successfully degraded using 0.1 mM of Fe at circumneutral pH with a consumption of 30 mg L-1 H2O2 with less than 45 min.

14.
Water Res ; 203: 117532, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34419922

RESUMO

In this study, a full cycle of agricultural reuse of agro-food wastewater (synthetic fresh-cut wastewater, SFCWW) at pilot plant scale has been investigated. Treated SFCWW by ozonation and two solar processes (H2O2/solar, Fe3+-EDDHA/H2O2/solar) was used to irrigate two raw-eaten crops (lettuce and radish) grown in peat. Two foodborne pathogens (E. coli O157:H7 and Salmonella enteritidis) and five organic microcontaminants (OMCs: atrazine, azoxystrobin, buprofezin, procymidone and terbutryn) were monitored along the whole process. The three studied processes showed a high treatment capability (reaching microbial loads < 7 CFU/100 mL and 21-90 % of OMC reduction), robustness (based on 7 or 10 analysed batches for each treatment process) and high suitability for subsequent treated SFCWW safe reuse: non-phytotoxic towards Lactuca sativa and no bacterial regrowth during its storage for a week. The analysis of the harvested crop samples irrigated with treated SFCWW in all the studied processes showed an absence of microbial contamination (< limit of detection, LOD; i.e., < 1 CFU/99 g of lettuce and < 1 CFU/8 g of radish), a significant reduction of OMC uptake (in the range 40-60 % and > 90 % for solar treated and ozonated SFCWW, respectively) and bioaccumulation in both crops in comparison with the results obtained with untreated SFCWW. Moreover, the chlorophyll content in the harvested lettuces irrigated with SFCWW treated by Fe3+-EDDHA/H2O2/solar was twice than that irrigated with SFCWW treated by H2O2/solar and ozone, indicating the additional advantage of using Fe3+-EDDHA as an iron source to reduce the risk of iron chlorosis in crops. Finally, the chemical (dietary risk assessment for the combined exposure of the 5 OMCs) and quantitative microbiological risk assessment (QMRA) of the harvested crops showed the capability of the studied processes to reduce the risk associated with untreated SFCWW reuse by more than 50 % and more than 4 orders of magnitude, respectively.


Assuntos
Anemia Hipocrômica , Escherichia coli O157 , Ozônio , Irrigação Agrícola , Peróxido de Hidrogênio , Lactuca , Águas Residuárias
15.
J AOAC Int ; 93(6): 1715-31, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21313798

RESUMO

Due to the wide range of pesticides that can be used in agriculture, the development of fast multiresidue methods that simultaneously determine polar and non-polar pesticides is greatly demanded. This study shows the development and validation of a multiresidue method for the analysis of 98 non-polar pesticides and 28 polar pesticides in soil. A simultaneous extraction step by pressurized liquid extraction was utilized. The optimum results were obtained using ethyl acetate-methanol (3:1, v/v) with 2 min of preheat time and 85 degrees C as the extraction temperature. The final determination of non-polar pesticides was performed by GC, whereas polar pesticides were determined by ultra-performance liquid chromatography (UPLC). Both GC and UPLC were coupled to triple-quadrupole analyzers operating in tandem MS. The optimized extraction procedure was validated. The average extraction recoveries were in the range 72-108% (10 microg/kg) and 71-106% (50 microg/kg), with RSD values < or = 26%. The matrix effect was also evaluated, and matrix-matched standard calibration was finally applied for quantification. The suitability of the method was also checked by the analysis of a certified reference material. Furthermore, 26 real soil samples were analyzed by the proposed methods in order to assess their applicability. Several pesticides (e.g., bifenthrin, triadimefon, or endosulfan) were found in the samples.


Assuntos
Resíduos de Praguicidas/análise , Praguicidas/análise , Poluentes do Solo/análise , Solo/análise , Cromatografia Gasosa , Cromatografia Líquida de Alta Pressão , Cromatografia com Fluido Supercrítico , Indicadores e Reagentes , Espectrometria de Massas , Padrões de Referência , Reprodutibilidade dos Testes , Manejo de Espécimes , Espectrometria de Massas em Tandem
16.
Phytochemistry ; 176: 112398, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32450381

RESUMO

This work presents the study of the roots of the Macaronesian paleoendemism Persea indica (L.) Spreng. The root biomass of this protected tree species has been produced by soil-less aeroponic culture under controlled environment. This system has important advantages over traditional plant production techniques because it provides opportunities to optimize the yield of metabolite production under well-controlled conditions, thereby facilitating commercial-scale production of bioactive compounds. Thus, for the first time a study of this type has permitted the isolation from the roots of seven undescribed dextrorotatory lactones: the alkane-γ-lactones (+)-majoranolide and (+)-dihydromajorenolide, the alkene-γ-lactones (+)-majorenolide and (+)-majorenolide acetate, and the alkyne-γ-lactones, (+)-majorynolide, (+)-majorynolide acetate and (+)-isomajorynolide. In addition, thirteen known compounds were also isolated including two possible avocadofurane precursors, avocadynone acetate and avocadenone acetate, the monoterpene esters cis- and trans-p-coumarate of (-)-borneol, and the ryanoid diterpenes cinnzeylanone, anhidrocinnzeylanine, cinnzeylanine, cinnzeylanol, epiryanodol, perseanol, cinncassiol E, perseaindicol and secoperseanol. The configuration at C-14 de two ryanodane diterpenes has also been revised in this work. Furthermore, (-)-borneol cis-p-coumarate has showed to be insecticidal to S. littoralis and cytotoxic to insect (Sf9) cells, (+)-majorenolide antifeedant to aphids and cytotoxic to Sf9, cinnceylanol antifeedant and insecticidal to S. littoralis, and (+)-majorynolide (2), insecticidal against S. littoralis, cytotoxic to Sf9 and nematicidal, suggesting a defensive role for these compounds.


Assuntos
Diterpenos , Persea , Alcanos , Alcenos , Alcinos , Animais , Lactonas , Raízes de Plantas
17.
Water Res ; 169: 115220, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31677437

RESUMO

The effect of the UV-C/free chlorine (FC) process on the removal of contaminants of emerging concern (CECs) from real urban wastewater as well as the effect of UV-C radiation on the formation of trihalomethanes (THMs) compared to FC process alone was investigated. Unlike of FC process, UV-C/FC was really effective in the degradation of the target CECs (carbamazepine (CBZ), diclofenac, sulfamethoxazole and imidacloprid) in real wastewater (87% degradation of total CECs within 60 min, QUVC = 1.33 kJ L-1), being CBZ the most refractory one (49.5%, after 60 min). The UV-C radiation significantly affected the formation of THMs. THMs concentration (mainly chloroform) was lower in UV-C/FC process after 30 min treatment (<1 µgL-1 = limit of quantification (LOQ)) than in FC process in dark (2.3 µgL-1). Noteworthy, while in FC treated wastewater chloroform concentration increased after treatment, UV-C/FC process resulted in a significant decrease (residual concentrations below the LOQ), even after 24 h and 48 h post-treatment incubation. The formation of radicals due to UV-C/FC process can reduce THMs compared to chlorination process, because part of FC reacts with UV-C radiation to form radicals and it is no longer available to form THMs. These results are encouraging in terms of possible use of UV-C/FC process as advanced treatment of urban wastewater even for possible effluent reuse.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Purificação da Água , Cloro , Desinfecção , Halogenação , Trialometanos , Raios Ultravioleta , Águas Residuárias
18.
J Agric Food Chem ; 67(25): 6930-6939, 2019 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-31150236

RESUMO

In many regions, reuse of reclaimed water (RW) is a necessity for irrigation. The presence of organic microcontaminants (OMCs) in RW and their translocation to plants may represent a risk of human exposure. Nevertheless, information available about real field crops is scarce and focused on a limited number of compounds. The novelty of this work relies on the application of a wider-scope analytical approach based on a multianalyte target analysis (60 compounds) and a suspect screening (>1300 compounds). This methodology was applied to real field-grown tomato crops irrigated with RW. The study revealed the presence of 17 OMCs in leaves (0.04-32 ng g-1) and 8 in fruits (0.01-1.1 ng g-1), 5 of them not reported before in real field samples. A health-risk assessment, based on the toxicological threshold concern (TTC) concept, showed that RW irrigation applied under the conditions given does not pose any threat to humans.


Assuntos
Frutas/química , Solanum lycopersicum/metabolismo , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Irrigação Agrícola , Transporte Biológico , Frutas/metabolismo , Humanos , Solanum lycopersicum/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Medição de Risco , Água/química , Poluentes Químicos da Água/metabolismo
19.
Chemosphere ; 232: 152-163, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31154175

RESUMO

Agriculture is considered as the main source of water contamination by pesticides. However, food packaging or processing industries are also recognised as relevant point sources of contamination by these compounds, not yet investigated in depth. The objective of this work has been to improve current knowledge about the presence and concentration of pesticides in the effluent of a food processing industry, as well as to investigate their main transformation products (TPs). An analytical strategy combining target and suspect analysis has been applied to provide an evaluation of the effluents. The methodology involves solid-phase extraction (SPE) of wastewater samples followed by (i) liquid chromatography quadrupole-linear ion trap tandem mass spectrometry (LC-QqLIT-MS/MS) for quantitative target analysis and (ii) liquid chromatography coupled to quadrupole-time-of-flight high resolution mass spectrometry (LC-QTOF-HRMS) to identify non-target pesticides and possible TPs. The results revealed the presence of 17 of the target pesticides analysed and 3 additional ones as a result of the suspect screening performed by HRMS. The TPs were investigated for the pesticides found at the highest concentrations: imazalil (7038-19802 ng/L), pyrimethanil (744-9591 ng/L) and thiabendazole (341-926 ng/L). Up to 14 TPs could be tentatively identified, demonstrating the relevance of this type of studies. These data provide a better understanding of the occurrence of pesticides and their TPs in agro-food industrial effluents.


Assuntos
Praguicidas/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Agricultura , Cromatografia Líquida/métodos , Monitoramento Ambiental , Indústria Alimentícia , Indústria de Processamento de Alimentos , Extração em Fase Sólida , Espectrometria de Massas em Tandem/métodos , Tiabendazol/análise , Águas Residuárias/análise , Poluição Química da Água/estatística & dados numéricos
20.
Anal Chem ; 80(24): 9450-9, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-19072261

RESUMO

A fast and straightforward generic procedure for the simultaneous extraction of various classes of pesticides, mycotoxins, plant toxins, and veterinary drugs in various matrixes has been developed, for subsequent analysis by liquid chromatography with mass spectrometric detection. As a first step, four existing multianalyte procedures and three newly proposed methods were compared for a test set of 172 pesticides, mycotoxins, and plant toxins spiked to a feed matrix. The new procedures, which basically involved extraction/dilution of the sample with water and an acidified organic solvent (methanol, acetonitrile, or acetone), were most promising. The three new generic extraction methods were further tested for applicability to other matrixes (maize, honey, milk, egg, meat). Overall, the best recoveries were obtained for acetone, followed by acetonitrile. With respect to matrix effects, acetonitrile was the most favorable solvent and methanol was the worst. The occurrence of matrix effects decreased for the matrixes in the order of feed > maize > meat > milk > egg > honey. The extraction method selected as the default procedure (water/acetonitrile/1% formic acid) was also evaluated for applicability to multiple classes of veterinary drugs in all six matrixes, with satisfactory results. Finally, the generic extraction procedure was validated for 136 pesticides, 36 natural toxins, and 86 veterinary drugs in compound feed and honey at three levels (0.01, 0.02, and 0.05 mg/kg) using ultraperformance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) for analysis of the extracts. For over 80% of the analytes, recoveries were between 70 and 120% and precision (expressed as relative standard deviation) was mostly in the range of 5-10% (except for feed at 0.01 mg/kg; adequate recoveries for 62% of the analytes). The limits of detection were from <0.01 to 0.05 mg/kg for most analytes, which is usually sufficient to verify compliance of products with legal tolerances. The results clearly demonstrate the feasibility of the generic approach proposed. Application of the method in routine monitoring programs would imply a drastic reduction of both effort and time.


Assuntos
Ração Animal/análise , Análise de Alimentos , Micotoxinas/análise , Praguicidas/análise , Toxinas Biológicas/análise , Drogas Veterinárias/análise , Acetona/química , Acetonitrilas/química , Animais , Cromatografia Líquida , Humanos , Espectrometria de Massas em Tandem
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