The taxonomic classification of the genus Vernonia Schreb is complex and, as yet, unclear. We here report the use of untargeted metabolomics approaches, followed by multivariate analyses methods and ...a phytochemical characterization of ten Vernonia species. Metabolic fingerprints were obtained by accurate mass measurements and used to determine the phytochemical similarities and differences between species through multivariate analyses approaches. Principal component analysis based on the relative levels of 528 metabolites, indicated that the ten species could be clustered into four groups. Thereby, V. polyanthes was the only species with presence of flavones chrysoeriol-7-O-glycuronyl, acacetin-7-O-glycuronyl and sesquiterpenes lactones piptocarphin A and piptocarphin B, while glaucolide A was detected in both V. brasiliana and V. polyanthes, separating these species from the two other species of the Vernonanthura group. Species from the Lessingianthus group were unique in showing a positive response in the foam test, suggesting the presence of saponins, which could be confirmed by metabolite annotation. V. rufogrisea showed a great variety of sesquiterpene lactones, placing this species into a separate group. Species within the Chrysolaena group were unique in accumulating clovamide. Our results of LC-MS-based profiling combined with multivariate analyses suggest that metabolomics approaches, such as untargeted LC-MS, may be potentially used as a large-scale chemotaxonomical tool, in addition to classical morphological and cytotaxonomical approaches, in order to facilitate taxonomical classifications.
Members of the subtribe Lychnophorinae occur mostly within the Cerrado domain of the Brazilian Central Plateau. The relationships between its 11 genera, as well as between Lychnophorinae and other ...subtribes belonging to the tribe Vernonieae, have recently been investigated upon a phylogeny based on molecular and morphological data. We report the use of a comprehensive untargeted metabolomics approach, combining HPLC-MS and GC-MS data, followed by multivariate analyses aiming to assess the congruence between metabolomics data and the phylogenetic hypothesis, as well as its potential as a chemotaxonomic tool. We analyzed 78 species by UHPLC-MS and GC-MS in both positive and negative ionization modes. The metabolic profiles obtained for these species were treated in MetAlign and in MSClust and the matrices generated were used in SIMCA for hierarchical cluster analyses, principal component analyses and orthogonal partial least square discriminant analysis. The results showed that metabolomic analyses are mostly congruent with the phylogenetic hypothesis especially at lower taxonomic levels (Lychnophora or Eremanthus). Our results confirm that data generated using metabolomics provide evidence for chemotaxonomical studies, especially for phylogenetic inference of the Lychnophorinae subtribe and insight into the evolution of the secondary metabolites of this group.
Carbendazim, a common pesticide, has shown signs of causing cancer, infertility and toxicity to organisms. Due to its intense use, this fungicide has become a persistent compound in the environment, ...raising the importance of better understanding its behaviour, metabolic pathways and effects on organisms. Zebrafish is considered an excellent animal model, being able to rapidly absorb compounds in water, mimicking what occurs in the aquatic environment. Therefore, the aim of this work was to evaluate carbendazim metabolites in zebrafish water tank using liquid chromatography coupled to a high-resolution mass spectrometer (LC-HRMS) to highlight analytical targets in order to monitor carbendazim exposure in aquatic environments. For this purpose, treatment, negative and stability groups were defined. In addition, water samples were collected from the tanks and analyses were carried out by LC-HRMS. The results allowed the putative annotation of 7 target metabolites. This study applied the analysis of zebrafish water tank for evaluation of target metabolites of carbendazim as a promising approach, since it is a much cleaner matrix than the usual biological matrices. These metabolites can ensure detectability and further strengthen confidence in monitoring carbendazim exposure in aquatic environments. To the best of our knowledge, there is no one study that has evaluated carbendazim metabolites produced by zebrafish, neither in the animal's body nor in the water tank. This is the first report on the generation of carbendazim metabolites by zebrafish.
Abstract
In the present investigation, we studied the floral bouquet and its associate osmophores in three legume trees using a combination of chemical and ultrastructural analyses, a poorly ...investigated approach to plant glands. The purpose was to understand the secretory process of osmophores and to identify which of the substances produced are responsible for the attraction of pollinators. Petals from buds and flowers of Bauhinia rufa, Caesalpinia pulcherrima and Hymenaea courbaril were fixed and processed for analysis by transmission electron microscopy. Fresh petals of H. courbaril and C. pulcherrima were also collected, submitted to a headspace solid-phase micro-extraction method and analysed using GC-MS. Typical subcellular features of terpene-secreting osmophores were detected: abundance of mitochondria with conspicuous cristae, plastids with plastoglobuli, rough endoplasmic reticulum and the presence of vesicles and oil droplets in the cytoplasm. Novel subcellular characters of osmophores were detected, such as cellular vacuolation in stages far preceding anthesis and a wealth of dictyosomes. The ultrastructure confirmed that the osmophores produce terpenes and phenolic compounds as previously reported. However, the GC-MS analyses showed that only the terpenes are released and could act on pollinator attraction. The phenolics accumulated are mobilized from these structures and metabolized/reabsorbed by the other plant tissues.
Purpose
This study aims to investigate a zebrafish (
Danio Rerio)
water tank (ZWT) as an alternative model for the study of the metabolism of xylazine.
Methods
The ZWT approach for the study of ...metabolism consisted of two aquariums, where 18 fish and xylazine were added into the first tank. The second one, with 18 fish without drug, served as a negative control. The samples were submitted to a comprehensive analytical method developed for doping control purposes by liquid chromatography (LC) coupled with high-resolution mass spectrometry (HRMS) operating in five different acquisition modes. Glycoconjugate metabolites were evaluated indirectly by extracting the samples with and without the enzymatic hydrolysis step using β-glucuronidase.
Results
In total, 11 phase I and II metabolites were detected and characterized, of which four were previously described for humans and two for horses, and five metabolites were described for the first time. The main metabolites were 4-hydroxylated (M2) and oxygenated (M1) derivatives. Both metabolites were suggested as analytical targets for xylazine misuse. Around 79% of para- and meta-hydroxylated derivatives were in glycoconjugate form, whereas for oxo-hydroxylated and sulfone-hydroxylated derivatives of xylazine, around 83% and 70% were metabolized to the glycoconjugate form, respectively.
Conclusions
Xylazine was the subject of extensive metabolism in zebrafish. 4-Hydroxylated (M2) and oxygenated (M1) derivatives were the most abundant phase I metabolites as the main targets for doping control.
One of the commonest pesticides used in agriculture is the fungicide carbendazim, which can cause deleterious effects on the physiology and behaviour of acutely and chronically exposed animals. ...However, few studies have evaluated the effects of carbendazim on fish behaviour and our main objective was to evaluate behavioural changes on adult zebrafish (
Danio rerio
) exposed to this fungicide. We studied 177 fishes, divided into control groups (not exposed) and treatment groups, exposed to a concentration of 120 µg/L for 7, 14, 21 and 28. Behavioural data were collected using the scan sampling, with instantaneous recording every 30 s. We evaluated and compared fish behaviours and aquarium occupancy between treatments and controls using Generalized Linear Mixed Models. The results indicate that carbendazim initially elicited slow swimming and later fast swimming, decreased aggressiveness, and caused behavioural changes indicative of distress, like abnormal swimming and the gulping of air in water surface. In the wild, this behavioural change can result in an increased predation risk and consequent decrease or extinction of populations, revealing important ecological issues for animal communities living in polluted water bodies.
•We performed a phytochemical study using leaves of Vernonia polyanthes Less (Asteraceae).•The compounds were isolated by prep. HPLC and prep. TLC and analyzed by spectroscopic methods (MS, 1H and ...13C NMR).•We isolated 12 compounds (sesquiterpene lactones, flavonoids and chlorogenic acids), none previously identified in this plant.•The compounds identified are in agreement with the chemical profile of the subtribe Vernoniinae.•Phytochemical studies may be useful as a tool for helping the understanding of taxonomic classification of the genus Vernonia.
Pesticides has transformed the agricultural industry, primarily by enhancing productivity. However, the indiscriminate use of such compounds can adversely affect human health and disrupt ecosystem ...balance. Limited knowledge exists regarding the removal of these compounds from water, particularly for organophosphate pesticides when employing conventional treatment technologies. Therefore, this study aimed to assess the removal of acephate (ACE) and methamidophos (MET) - considered priority pesticides in Brazil - from waters with high and low turbidity during the clarification process carried out with aluminum sulfate (AS) and ferric chloride (FC), either alone or combined with powdered activated carbon (PAC) adsorption. All water samples were submitted to solid phase extraction (SPE C18 cartridges) prior to acephate and methamidophos analysis by HPLC MS/MS. The clarification process with either AS or FC coagulant did not efficiently remove acephate or methamidophos and maximum average removal (27 %) was observed with waters of high turbidity when using ferric chloride as coagulant. Addition of mineral PAC was also ineffective for removing both pesticides. However, the use of vegetable PAC (10 mg/L) resulted in better removal percentages, up to 80%, but only for methamidophos. The limited removal rates were attributed to the high hydrophilicity of acephate and methamidophos, along with their neutral charge at coagulation pH. These factors hinder the interaction of such organophosphorus pesticides with the flocs formed during coagulation as well as with PAC surface.
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•Coagulation minimally removed acephate (ACE) and methamidophos (MET) from water.•Powered activated carbon (PAC) from mineral coal did not remove either pesticide effectively.•PAC (10 mg/L) from pine wood was a best adsorbent for methamidophos removal.•ACE and MET hydrophilic nature likely contributed to limited removal from water.
Tebuconazole is a triazole fungicide widely used in agricultural crops for control of multiple fungal, mainly foliar and soil-borne diseases. Due to its intense use, this pesticide has been detected ...on aquatic matrices in different countries, which makes it necessary to identify metabolites capable to be used in its exposure monitoring. The aim of this work was to evaluate tebuconazole metabolites in zebrafish water tanks using liquid chromatography coupled to a high-resolution mass spectrometer (LCHRMS) to highlight analytical targets to monitor tebuconazole exposure in aquatic environments. Two Phase I metabolites, TEB-OH and TEB-COOH, and one Phase II metabolite, TEB-S, were identified. Target metabolomics pointed TEB-S as the most important metabolite for discrimination between treatment and negative control group and potential surrogate for detection and monitoring of tebuconazole exposure in aquatic environments. To the best of our knowledge, this is the first study to suggest the sulphation of tebuconazole (TEB-S) by zebrafish metabolism. Moreover, the use of water samples proved to be a promising approach when compared to the usual biological matrices (e.g. plasma) for evaluating the exposure of aquatic animals to tebuconazole because it is a clean and easy to obtain matrix. Water samples presented a higher concentration of metabolites when compared to plasma samples. The results suggest the applicability of this assay model for the identification of potential biomarkers for monitoring the presence of xenobiotics in water.
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