Products derived from the latex of were obtained through hydrolysis and column chromatography, resulting in products rich in triterpenes, ingenol 3-esters (I3E), and other derivatives from hydrolysed latex. These products underwent evaluation for their cytotoxic activity against gastric adenocarcinoma cells (AGS). Triterpene derivatives were synthesised, and the selectivity of each product was assessed.
View Article and Find Full Text PDFleaves are a rich source of phenolic compounds with biological activities, including myricitrin. In this study, the chemical profile of nine extracts prepared with leaves collected in three regions (mountain, beach, and mangrove) and at three different times of the day (8 am, 1 pm, and 6 pm) was evaluated from spectra originating from ultra-high resolution mass spectrometry (Fourier transform ion cyclotron resonance, FT-ICR) coupled to electrospray ionisation (ESI). The best time of the day and location for collecting the leaves of used as raw materials for producing extracts and the best ethanol concentration for obtaining an extract more abundant in compounds of interest were verified.
View Article and Find Full Text PDFFTIR spectroscopy and multivariate analysis were used in the chemical study of the terroirs of Coffea canephora. Conilon coffees from Espírito Santo and Amazon robusta from Matas of Rondônia, were separated by PCA, with lipids and caffeine being the markers responsible for the separation. Coffees from Bahia, Minas Gerais, and São Paulo did not exhibit separation, indicating that the botanical variety had a greater effect on the terroir than geographic origin.
View Article and Find Full Text PDFConsidering the great economic significance of (arabica) associated with the lower production cost of (conilon), blends of these coffees are commercially available to reduce costs and combine sensory attributes. Thus, analytical tools are required to ensure consistency between real and labeled compositions. In this sense, chromatographic methods based on volatile analysis using static headspace-gas chromatography-mass spectrometry (SHS-GC-MS) and Fourier transform infrared (FTIR) spectroscopy associated with chemometric tools were proposed for the identification and quantification of arabica and conilon blends.
View Article and Find Full Text PDFEthanol extract from the aerial parts of L. as well as the latex of the plant suspended in water are used by the Brazilian population for the treatment of various diseases, including cancer. The purposes of this study were to determine if the ethanol extract is effective as cytotoxic agent against gastric adenocarcinoma cells (AGS) and its chemical composition by GC-MS, ESI-(-)-FT-ICR MS and (-)-ESI-LTQ-MS/MS.
View Article and Find Full Text PDFThe use of drugs of abuse has grown significantly in recent decades. In forensic chemistry, methods of identifying and characterizing illicit drugs contribute to the interests of researchers, experts, and public security authorities. Among existing methods, portable Raman spectroscopy is notable for performing rapid, non-destructive, and highly selective analysis in the laboratory or on-site.
View Article and Find Full Text PDFSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the worst global health crisis in living memory. The reverse transcription polymerase chain reaction (RT-qPCR) is considered the gold standard diagnostic method, but it exhibits limitations in the face of enormous demands. We evaluated a mid-infrared (MIR) data set of 237 saliva samples obtained from symptomatic patients (138 COVID-19 infections diagnosed via RT-qPCR).
View Article and Find Full Text PDFThe chemical complexity of coffee influences the sensory evaluation of the beverage, the main method used to define the quality of the coffee. In view of the subjectivity that method offers, we propose the association of an instrumental method with multivariate calibration (PLS and GA-SVR) to predict the quality of arabica coffee as support for sensory analysis. Arabica coffee samples were submitted to sensory evaluation using the Specialty Coffee Association (SCA) protocol and HS-SPME-GC/MS analysis.
View Article and Find Full Text PDFMilk is a homogeneous mixture of substances such as lactose, proteins, and glycerides. Among carbohydrates, lactose is a disaccharide composed of glucose and galactose, and it is present in bovine milk at a level of 4.6%.
View Article and Find Full Text PDFJ Mass Spectrom
October 2020
The consumption of design drugs, frequently known as new psychoactive substances (NPS), has increased considerably worldwide, becoming a severe issue for the responsible governmental agencies. These illicit substances can be defined as synthetic compounds produced in clandestine laboratories in order to act as analogs of schedule drugs mimetizing its chemical structure and improving its pharmacological effects while hampering the control and making regulation more complicated. In this way, the development of new methodologies for chemical analysis of NPS drugs is indispensable to determine a novel class of drugs arising from the underground market.
View Article and Find Full Text PDFRationale: Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) is an important analytical technique used for the elucidation of crude oil polar compounds at the molecular level, providing thousands of heteroatom compounds in a single analysis. Due to the high resolution, the complexity of data produced, and steps involved in spectra acquisition and processing, it is necessary to estimate its intermediate precision.
Methods: Intermediate precision was estimated for positive- and negative-ion ionization modes (ESI(±)) using Composer® software for two Brazilian crude oil samples.
We have built an online tool with a user-friendly and browser-based interface to facilitate the processing of high resolution and precision oil mass spectrometry data. DropMS does not require software installations. Mass spectra are sent and processed by the server using various algorithms reported in the literature, such as S/N ratio filters, recalibrations, chemical formula assimilations, and data visualization using graphs and diagrams popularly known in mass spectrometry as Van Krevelen and Kendrick diagrams and DBE vs C#.
View Article and Find Full Text PDFThe study of Brazilian Conilon coffee genotypes with unknown chemical composition and sensory quality is extremely important since these data may contribute to the launching of new coffee cultivars in the international market with high cup quality. The present study aimed to investigate the metabolic profile of 3 genotypes of Conilon and compared them to Robusta Tropical and Arabica coffees, all collected at 3 different levels of ripeness. The extracts were analysed by ESI-LTQ-ORBITRAP, and 11 attributes were evaluated by sensory analysis.
View Article and Find Full Text PDFEthnopharmacological Relevance: Euphorbia tirucalli L. is widely used by Brazilian folk medicine, mainly for its anticancer activity. However, its commercialization was banned by The Brazilian National Sanitary Surveillance Agency (ANVISA) due to the presence of some compounds considered toxic, such as the diterpene esters.
View Article and Find Full Text PDFGuar gum is used in low concentrations as a drag reducing agent in turbulent flows to significantly accelerate flow in oil pipelines, oil well operations and aqueous systems. Drag reduction also promotes a decrease in energy demand in pumping systems. However, the polymers undergo mechanical degradation and lose the ability to promote drag reduction over time.
View Article and Find Full Text PDFMarijuana, a drug derived from the Cannabis sativa L. plant, is the world's most consumed illicit drug. In this paper, a total of 156 marijuana samples seized in the state of Espírito Santo (ES), Brazil were studied and analysed by proton nuclear magnetic resonance (H NMR) spectroscopy to identify the major cannabinoids present.
View Article and Find Full Text PDFThe use of portable micro-spectrometers such as a micro near infrared region (microNIR) spectrometer is a promising technique for solving analytical problems in several areas of science. This work evaluated the potential of microNIR in quality control of Arabica coffee. Arabica coffee has a high commercial value product, motivating the development of analytical methods with high sensitivity and accuracy for detection of its adulteration.
View Article and Find Full Text PDFFuel quality control has gained interest in many countries owing to the potential damage of low-quality fuel to engines, the environment, and economy. Thus, the application of analytical techniques to verify quality control of fuels has become crucial. The portable micro-spectrometer in the near infrared region (microNIR) has gained credibility as a successful analytical technique in several quality control sectors.
View Article and Find Full Text PDFCocaine is a stimulant drug of the central nervous system (CNS) extracted from the leaves of Erytroxylum coca. It is defined as a tropane alkaloid containing 1R-(exo,exo)-3-(benzoyloxy)-8-methyl-8-azabicyclo[3.2.
View Article and Find Full Text PDFThin layer chromatography (TLC) is a simple and inexpensive type of chromatography that is extensively used in forensic laboratories for drugs of abuse analysis. In this work, TLC is optimized to analyze cocaine and its adulterants (caffeine, benzocaine, lidocaine and phenacetin) in which the sensitivity (visual determination of LOD from 0.5 to 14mgmL(-1)) and the selectivity (from the study of three different eluents: CHCl3:CH3OH:HCOOHglacial (75:20:5v%), (C2H5)2O:CHCl3 (50:50v%) and CH3OH:NH4OH (100:1.
View Article and Find Full Text PDF