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1.
Microbiol Res ; 275: 127469, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37543005

RESUMO

The genus Trichoderma comprises more than 500 valid species and is commonly used in agriculture for the control of plant diseases. In the present study, a Trichoderma species isolated from Scleronema micranthum (Malvaceae) has been extensively characterized and the morphological and phylogenetic data support the proposition of a new fungal species herein named Trichoderma agriamazonicum. This species inhibited the mycelial growth of all the nine phytopathogens tested both by mycoparasitism and by the production of VOCs, with a highlight for the inhibition of Corynespora cassiicola and Colletotrichum spp. The VOCs produced by T. agriamazonicum were able to control Capsicum chinense fruit rot caused by Colletotrichum scovillei and no symptoms were observed after seven days of phytopathogen inoculation. GC-MS revealed the production of mainly 6-amyl-α-pyrone, 1-octen-3-ol and 3-octanone during interaction with C. scovillei in C. chinense fruit. The HLPC-MS/MS analysis allowed us to annotate trikoningin KBII, hypocrenone C, 5-hydroxy-de-O-methyllasiodiplodin and unprecedented 7-mer peptaibols and lipopeptaibols. Comparative genomic analysis of five related Trichoderma species reveals a high number of proteins shared only with T. koningiopsis, mainly the enzymes related to oxidative stress. Regarding the CAZyme composition, T. agriamazonicum is most closely related to T. atroviride. A high protein copy number related to lignin and chitin degradation is observed for all Trichoderma spp. analyzed, while the presence of licheninase GH12 was observed only in T. agriamazonicum. Genome mining analysis identified 33 biosynthetic gene clusters (BGCs) of which 27 are new or uncharacterized, and the main BGCs are related to the production of polyketides. These results demonstrate the potential of this newly described species for agriculture and biotechnology.


Assuntos
Hypocreales , Trichoderma , Trichoderma/metabolismo , Filogenia , Espectrometria de Massas em Tandem , Hypocreales/genética
2.
Chemosphere ; 326: 138365, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36906004

RESUMO

The evaluation of contamination by domestic sewage is relevant in the Amazon region; however, it has neither been well-developed nor accompanied by research or monitoring programs. In this study, caffeine and coprostanol as indicators of sewage were investigated in water samples from Amazonian water bodies that crisscross the city of Manaus (Amazonas state, Brazil) and cover regions with distinct main land uses such as high-density residential, low-density residential, commercial, industrial, and environmental protection areas. Thirty-one water samples were studied based on their dissolved and particulate organic matter (DOM and POM) fractions. Quantitative determination of both caffeine and coprostanol was carried out using LC-MS/MS with APCI in the positive ionization mode. The streams of the urban area of Manaus had the highest concentrations of caffeine (1.47-69.65 µg L-1) and coprostanol (2.88-46.92 µg L-1). Samples from the peri-urban Tarumã-Açu stream and from the streams in the Adolpho Ducke Forest Reserve showed much lower concentrations of caffeine (20.20-165.78 ng L-1) and coprostanol (31.49-120.44 ng L-1). Samples from the Negro River showed a wider range of concentrations of caffeine (20.59-873.59 ng L-1) and coprostanol (31.72-706.46 ng L-1), with the highest values found in the outfalls of the urban streams. Levels of caffeine and coprostanol were significantly positively correlated in the different organic matter fractions. The coprostanol/(coprostanol + cholestanol) ratio proved to be a more suitable parameter than the coprostanol/cholesterol one in low-density residential areas. Proximity to densely populated areas and the flow of water bodies appear to influence the caffeine and coprostanol concentrations, which was observed in their clustering in the multivariate analysis. The results indicate that caffeine and coprostanol can be detected even in water bodies that receive very low domestic sewage input. Therefore, this study revealed that both caffeine in DOM and coprostanol in POM represent viable alternatives for use in studies and monitoring programs even in remote areas of the Amazon, where microbiological analyses are often unfeasible.


Assuntos
Colestanol , Poluentes Químicos da Água , Colestanol/análise , Esgotos/análise , Cafeína/análise , Cromatografia Líquida , Monitoramento Ambiental/métodos , Espectrometria de Massas em Tandem , Água/análise , Poluentes Químicos da Água/análise
3.
Aquat Toxicol ; 241: 105997, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34688140

RESUMO

The main toxicity mechanism of organophosphate insecticides such as malathion is the acetylcholinesterase enzyme inhibition. However, fish responses to organophosphates may vary depending on the activation of different defense mechanisms as well as the length of exposure. As such, the evaluation of acetylcholinesterase activity, in combination with the evaluation of biotransformation and antioxidants enzymes levels, is useful for indicating damage in fish exposed to this insecticide. Moreover, evaluating mitochondrial activity might evidence how the hierarchic responses occur in relation to the length of time that the fish is exposed. Therefore, the aim of our study is to evaluate whether the length of exposure to malathion differentially affects the biochemical responses of tambaqui. Our hypothesis is that the physiological alterations due to exposure are time dependent. Fish were exposed to sublethal concentrations of the insecticide during 6, 12, 24, 36, and 48 h. Contrary to expectations, there was no acetylcholinesterase activity inhibition during the experiment, which indicates an absence of neurotoxicity. Phase II biotransformation mechanism was activated early, especially in the liver. Oxidative damage was evident in the first hours of exposure and was concurrent with the activation of antioxidant enzymes. Mitochondrial bioenergetics were differentially affected by the length of exposure. The data suggest that the tambaqui regulates mitochondrial respiration differently over time, seeking to maintain homeostasis and ATP demand, and ensures the activation of response mechanisms, thus minimizing oxidative damage and avoiding the neurotoxicity of malathion.


Assuntos
Caraciformes , Inseticidas , Poluentes Químicos da Água , Acetilcolinesterase , Animais , Inseticidas/toxicidade , Malation/toxicidade , Poluentes Químicos da Água/toxicidade
4.
Environ Pollut ; 244: 818-826, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30390455

RESUMO

Sewage pollution is a principal factor of decreasing water quality, although it has not been considered a real impact in Amazonia that is still considered a pristine environment around the world. Thus, this study aimed to assess the levels of sewage contamination in sediments from three streams crossing Manaus - a Brazilian city of 2,403,796 inhabitants in the heart of the Amazon rain forest. Cholesterol, cholestanol, brassicasterol, ergosterol, stigmasterol, ß-sitosterol, campesterol, stigmastanol, coprostanol, and epicoprostanol levels were determined by liquid chromatography tandem mass spectrometry (LC-MS/MS). The fecal indicator, coprostanol, was found in high concentrations (509-12 830 ng g-1) and high relative proportions (21-54%) in all samples collected in the Mindu stream that crosses many heavily populated districts of the city, and in the Quarenta stream that crosses the Industrial District of Manaus. The sediments of the Tarumã-Açu stream also presented coprostanol; however, concentrations (

Assuntos
Monitoramento Ambiental/métodos , Rios/química , Esteróis/análise , Poluentes da Água/análise , Poluição da Água/análise , Qualidade da Água , Biomarcadores/análise , Brasil , Colestadienóis/análise , Colestanol/análise , Colestanóis/análise , Colesterol/análogos & derivados , Colesterol/análise , Cromatografia Líquida , Contaminação de Medicamentos , Fezes , Sedimentos Geológicos/química , Fitosteróis/análise , Esgotos/análise , Sitosteroides/análise , Espectrometria de Massas em Tandem
5.
Int J Anal Chem ; 2018: 2560498, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30627163

RESUMO

The performance of gas chromatography coupled to high-resolution time-of-flight mass spectrometry (GC-HRTofMS) for characterizing geochemical biomarkers from sediment samples was evaluated. Two approaches to obtain the geochemical biomarkers were tested: (1) extraction with organic solvent and subsequent derivatization and (2) in-situ derivatization thermal desorption. Results demonstrated that both approaches can be conveniently applied for simultaneous characterization of many geochemical biomarkers (alkanes, alkanols, sterols, and fatty acids), avoiding conventional time-consuming purification procedures. GC-HRTofMS reduces both sample preparation time and the number of chromatographic runs compared to traditional methodologies used in organic geochemistry. Particularly, the approach based on in-situ derivatization thermal desorption represents a very simple method that can be performed in-line employing few milligrams of sediment, eliminating the need for any sample preparation and solvent use. The high resolving power (m/Δm 50% 25,000) and high mass accuracy (error ≤ 1 ppm) offered by the "zig-zag" time-of-flight analyzer were indispensable to resolve the complexity of the total ion chromatograms, representing a high-throughput tool. Extracted ion chromatograms using exact m/z were useful to eliminate many isobaric interferences and to increase significantly the signal to noise ratio. Characteristic fragment ions allowed the identification of homologous series, such as alkanes, alkanols, fatty acids, and sterols. Polycyclic aromatic hydrocarbons were also identified in the samples by their molecular ions. The characterization of geochemical biomarkers along a sedimentary core collected in the area of Valo Grande Channel (Cananéia-Iguape Estuarine-Lagunar System (São Paulo, Brazil)) provided evidences of environmental changes. Sediments deposited before opening of channel showed dominance of biomarkers from mangrove vegetation, whereas sediments of the pos-opening period showed an increase of biomarkers from aquatic macrophyte (an invasive vegetation).

6.
J Food Sci ; 81(9): C2206-17, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27490163

RESUMO

This study was aimed to assess the effect of time and temperature on the extraction of antioxidant compounds from jabuticaba seeds (Myrciaria cauliflora cv. Sabará), to optimize the solvent proportion (water, ethyl alcohol, and propanone), and to characterize the extract according to the chemical composition, antioxidant, and antimicrobial properties. Proximal composition, total phenolic content (TPC), antioxidant, and antimicrobial activities were analyzed. The optimized solvent ratio of 60% water and 40% propanone provided a mean TPC of 8.65 g GAE/100 g seeds and the antioxidant activity toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) was 82.79% ± 0.50%. Time and temperature parameters did not influence the yield of TPC. The gross seed extract was partially purified and both exhibited a high antioxidant activity and antimicrobial potential toward Gram-positive and Gram-negative bacteria. The purified jabuticaba seed lyophilized extract contained a higher (P < 0.05) TPC, o-diphenols, flavonols, and antioxidant activity measured by the DPPH assay and total reducing capacity as compared to the gross lyophilized extract. Electrospray ionization coupled with tandem mass spectrometry (ESI-MS/MS) data showed the presence of ellagitannins and ellagic acid in the extracts, which are probably the responsible for the antimicrobial and antioxidant activities.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Myrtaceae/química , Extratos Vegetais/química , Sementes/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Ácido Elágico/análise , Ácido Elágico/farmacologia , Flavonóis/química , Flavonóis/farmacologia , Frutas/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Taninos Hidrolisáveis/análise , Taninos Hidrolisáveis/farmacologia , Fenóis/química , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem
7.
Nat Prod Bioprospect ; 6(4): 195-204, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27169570

RESUMO

The increasing demand for safe food without preservatives or pesticides residues has encouraged several studies on natural products with antifungal activity and low toxicity. In this study, ethanolic extracts from leaves and fruit residues (peel and seeds) of three Brazilian savanna species (Acrocomia aculeata, Campomanesia adamantium and Caryocar brasiliense) were evaluated against phytopathogenic fungi. Additionally, the most active extract was chemically characterized by ESI-MS and its oral acute toxicity was evaluated. Extracts from C. brasiliense (pequi) peel and leaves were active against Alternaria alternata, Alternaria solani and Venturia pirina with minimal inhibitory concentrations between 350 and 1000 µg/mL. When incorporated in solid media, these extracts extended the lag phase of A. alternata and A. solani and reduced the growth rate of A. solani. Pequi peel extract showed better antifungal activity and their ESI-MS analysis revealed the presence of substances widely reported as antifungal such as gallic acid, quinic acid, ellagic acid, glucogalin and corilagin. The oral acute toxicity was relatively low, being considered safe for use as a potential natural fungicide.

8.
Int J Anal Chem ; 2016: 8361375, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27087811

RESUMO

Sterols and triterpenols present in sedimentary cores from 12 stations along the Cananéia-Iguape estuarine-lagoonal system were investigated by ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Ten sterols and three triterpenols were identified and quantified, indicating both natural and anthropogenic sources. The relative distributions of sterol and triterpenol showed that the study area is submitted to organic matter (OM) from the Ribeira de Iguape River, seawater, surrounding vegetation, and plankton production. The contribution of these sources depends on the region of the estuarine-lagoonal system and the depth of sediment. Regarding anthropogenic sources, only the samples submitted to freshwater flow from the Ribeira de Iguape River presented concentration of coprostanol higher than the threshold value and diagnostic ratios, coprostanol/(coprostanol + cholestanol) and coprostanol/cholesterol, that indicate moderate contamination by domestic sewage in that area of the estuarine-lagoonal system. Therefore, the approach used herein identified the OM sources and its transport along the Cananéia-Iguape estuarine-lagoonal system (Brazil), which is a complex of lagoonal channels located in a United Nations Educational, Scientific and Cultural Organization (UNESCO) Biosphere Reserve.

9.
J Trace Elem Med Biol ; 33: 37-47, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26653742

RESUMO

The aim of this study was to investigate if purple carrot extract is able to protect against the noxious activities induced by cadmium exposure in multiple organs of rats. For this purpose, histopathological analysis, genotoxicity and oxidative status were investigated in this setting. A total of twenty Wistar rats weighing 250g on the average, and 8 weeks age were distributed into four groups (n=5), as follows: Control group (non-treated group, CTRL); Cadmium group (Cd) and Purple carrot extract groups at 400mg/L or 800mg/L. Histopathological analysis revealed that liver from animals treated with purple carrot extract improved tissue degeneration induced by cadmium intoxication. Genetic damage was reduced in blood and hepatocytes as depicted by comet and micronucleus assays in animals treated with purple carrot extract. SOD-CuZn and cytocrome C gene expression increased in groups treated with purple carrot extract. Purple carrot extract also reduced the 8OHdG levels in liver cells when compared to cadmium group. Taken together, our results demonstrate that purple carrot extract is able to protect against cadmium intoxication by means of reducing tissue regeneration, genotoxicity and oxidative stress in multiple organs of Wistar rats.


Assuntos
Intoxicação por Cádmio/tratamento farmacológico , Daucus carota/química , Mutagênicos/toxicidade , Especificidade de Órgãos , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , 8-Hidroxi-2'-Desoxiguanosina , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Intoxicação por Cádmio/metabolismo , Ensaio Cometa , Citocromos c/metabolismo , Dano ao DNA , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Fígado/efeitos dos fármacos , Fígado/patologia , Testes para Micronúcleos , Extratos Vegetais/farmacologia , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Espectrometria de Massas por Ionização por Electrospray , Aumento de Peso/efeitos dos fármacos
10.
Anal Chem ; 87(15): 7771-8, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26132310

RESUMO

A fast, sensitive, and selective ultrahigh-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method that is able to quantify geochemical biomarkers in sediment is described. A pool of 10 sterols, which can be used as biomarkers of autochthonous (cholesterol, cholestanol, brassicasterol, ergosterol), allochthonous (stigmasterol, ß-sitosterol, campesterol, and stigmastanol) and anthropogenic (coprostanol and epicoprostanol) organic matter (OM), and three triterpenols (lupeol, α-amyrin, and ß-amyrin) were chosen as the analytes. The method showed excellent analytical parameters, and, compared with the traditional GC-MS methods that are commonly applied for the analysis of sterols, this method requires no sample cleanup or derivatization and presents improved values for the LOD and LOQ. UHPLC can separate the diastereoisomers (epicoprostanol, coprostanol, and cholestanol) and the isomers (lupeol, α-amyrin, and ß-amyrin). The method was successfully applied for the quantification of the biomarkers, and thus, it was applied to assess the OM sources and the impacts of anthropogenic activities in sediments from different environments, such as Antarctica and other Brazilian systems (Continental Shelf, São Sebastião Channel, and Santos Estuary). Unique profiles of the biomarkers were observed for the contrasting environments, and ß-amyrin and cholesterol were more predominant in the Santos Estuary and Antarctica samples, respectively. The sterol ratios indicated a higher level of sewage contamination in the Santos Estuary.


Assuntos
Cromatografia Líquida , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Esteróis/análise , Espectrometria de Massas em Tandem , Triterpenos/análise , Limite de Detecção , Fatores de Tempo
11.
Anal Bioanal Chem ; 407(23): 7221-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26168971

RESUMO

A simple extraction protocol and an ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) method for the determination of the syringyl/guaiacyl (S/G) ratio in lignin is reported herein. The method was entirely developed using stems of three Eucalyptus species, which were hydrolyzed with NaOH and partitioned with ethyl ether; vanillin (from the G monomer) and syringaldehyde (from S monomer) were quantified. The S/G ratios obtained were comparable to those usually reported for eucalyptus. The data for one of the eucalyptus species were compared with those obtained with a widely accepted method using thioacidolysis and gas chromatography-mass spectrometry (GC-MS). The method was also applied to sugarcane and showed to be reliable. The yield of the NaOH hydrolysis of the monolignols ranged from 89.94 to 95.69%, with more than 77.12% of recuperation in the liquid-liquid extraction. The whole analytical procedure was validated, achieving results with less than 4.38% of variation. The lowest LOD and LOQ were 0.01 and 0.05 µg/mL, respectively. In addition, the method combines reliability and a fast and direct quantification.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Eucalyptus/química , Lignina/análise , Lignina/química , Espectrometria de Massas/métodos , Saccharum/química , Algoritmos , Eucalyptus/classificação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Especificidade da Espécie
12.
Int J Food Sci Nutr ; 66(4): 439-44, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25835042

RESUMO

The aim of this study was to investigate the phenolic composition of a natural food colourant (G8000™) as well as its effects on plasma markers after 28-day consumption by healthy individuals at a dietary dose (70 g). Parameters of total cholesterol and its fractions, triglycerides and plasma enzymes biomarkers of muscle injury were measured. Major compounds identified in G8000™ by ESI-MS showed the presence of anthocyanins, organic acids, phenolic acids as well as monosaccharides. HDL levels significantly increased from 43 ± 10.2 mg/dL to 95 ± 16.9 mg/dL. LDL levels significantly decreased from 110 ± 40.9 mg/dL to 69 ± 39 mg/dL (p < 0.001). No significant statistical differences (p > 0.05) were observed for total cholesterol, triglycerides and VLDL. After the intake, plasma enzyme CK-MB decreased from 20 ± 12.1 U/L to 10 ± 1.9 U/L while LDH levels increased from 275 ± 124.4 U/L to 317 ± 114.7 U/L (p < 0.005). No significant differences were observed for CK levels. Taken together, dietary intake of natural colourant G8000™ was able to exert beneficial effects on atherosclerosis biomarkers.


Assuntos
HDL-Colesterol/sangue , LDL-Colesterol/sangue , Corantes de Alimentos/farmacologia , Extratos Vegetais/sangue , Extratos Vegetais/farmacologia , Vitis , Adulto , Biomarcadores/sangue , Feminino , Corantes de Alimentos/metabolismo , Humanos , Masculino , Fenóis/sangue , Fenóis/farmacologia , Triglicerídeos/sangue , Adulto Jovem
13.
Molecules ; 19(11): 17604-18, 2014 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-25361424

RESUMO

New N-p-chloro-, N-p-bromo-, and N-p-nitrophenylazobenzylchitosan derivatives, as well as the corresponding azophenyl and azophenyl-p-sulfonic acids, were synthesized by coupling N-benzylvchitosan with aryl diazonium salts. The synthesized molecules were analyzed by UV-Vis, FT-IR, 1H-NMR and 15N-NMR spectroscopy. The capacity of copper chelation by these materials was studied by AAS. Chitosan and the derivatives were subjected to hydrolysis and the products were analyzed by ESI(+)-MS and GC-MS, confirming the formation of N-benzyl chitosan. Furthermore, the MS results indicate that a nucleophilic aromatic substitution (SnAr) reaction occurs under hydrolysis conditions, yielding chloroaniline from N-p-bromo-, and N-p-nitrophenylazo-benzylchitosan as well as bromoaniline from N-p-chloro-, and N-p-nitrophenylazobenzyl-chitosan.


Assuntos
Quitosana/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Hidrólise , Espectroscopia de Ressonância Magnética/métodos , Estrutura Molecular , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
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