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The Cannabis sativa L. plant is a species rich in a variety of cannabinoid compounds and Δ9-tetrahydrocannabinol (Δ9-THC) has been reported as a main psychotropic substance.

Petroleum molecules with interfacial activity play a fundamental role in stabilizing water-in-oil (W/O) emulsions and thus have been the focus of many studies. Using the wet silica method, crude oil samples from Brazilian fields (designated P5 and P6) were fractionated into two fractionsone with the interfacially active molecules (IA) and another containing the non-interfacially active molecules (NIA). This fractionation was performed using a mixture of cyclohexane/toluene (1:1 v/v) (CH/TOL) for oils P5 and P6 and n-octane/toluene (1:1 v/v) (OC/TOL) only for oil P6 to evaluate the influence of the solvent system on the profile of the fractions obtained. The fractions obtained and the parent oils were characterized chemically by Fourier-transform infrared spectroscopy (FTIR), 1H-nuclear magnetic resonance (1H-NMR), and electrospray ionization Fourier-transform ion cyclotron resonance mass spectrometry (ESI (±) FT-ICR MS) and analyzed for interfacial activity using systems composed of brine (aqueous phase) and n-heptane/toluene mixture (organic phase). The results from FTIR and 1H-NMR evidenced the polar and aromatic character of the IA fractions, while the predominantly hydrocarbon composition was observed in the NIA fractions as well as their respective parent oils. The characterization by FT-ICR MS showed the influence of the solvent system on the basic species of the IA fractions, by ESI (+), and a difference in the acid compounds of the fractions isolated from the two parent oils, by ESI (−): the IA fraction isolated from P5 presented the compound classes O4[H] and O2[H] as major components, while the major compounds in the IA fractions isolated from P6 with CH/TOL or OC/TOL were O­[H], O2[H], and N­[H]. Decrease in the interfacial tension values on the order of 30% was observed when comparing each interfacially active fraction with their parent oil.

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Fresh and aged coconut water (CW) samples were introduced directly into the electrospray ionisation (ESI) source, and were combined with the Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) technique to characterise in situ chemical compounds produced during natural ageing (from 0 to 15 days) at room temperature (23 °C). The ESI-FT-ICR MS readings were acquired and the data were correlated to conventional methodologies: pH, total titratable acidity (TA), total soluble solids, microbial analyses, and ultraviolet visibility (UV-vis) spectroscopy analysis. In general, the pH and TA values changed after 3 days of storage making the CW unsuitable for consumption. The ESI(-)-FT-ICR data also showed a clear and evident change in the chemical profile of CW after 3 days of ageing in the m/z 150-250 and 350-450 regions. Initially, the relative intensity of the natural markers (the m/z 215 and 377 ions-sugar molecules) decreases as a function of ageing time, with the last marker disappearing after 3 days of ageing. New chemical species were then identified such as: citric (m/z 191), galacturonic (m/z 193), gluconic (m/z 195), and saccharic (m/z 209) acids. ESI(-)-FT-ICR MS is a powerful tool to predict the physicochemical properties of CW, such as the pH and TA, where species such as fructose, glucose, sucrose, and gluconic acid can be used as natural markers to monitor the quality of the fruits.

Rationale 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. The analytical parameters evaluated were the class distribution histogram, the double bond equivalent (DBE) distribution, and the DBE versus carbon number. The statistical parameters used to study the intermediate precision were calculated from the average, standard deviation, confidence interval (significance level at 5%), coefficient of variation (CV), intermediate precision limit (ISO 5725), and principal component analysis (PCA). Results Two crude oil samples (A and B) were analyzed, in triplicate, for seven consecutive days by ESI(±) FT‐ICR MS. The assigned class limit by ESI(+) for crude oil A was 0.42% (O2S[H] class) and for crude oil B was 0.04% (N2O2S[H] class). The assigned DBE intensity limits for the two crude oils were 0.04% for ESI(+) and 0.013% for ESI(−). The PCA for ESI(−) and ESI(+) modes presented better precision for crude oils B and A, respectively. Conclusions The most abundant classes and DBE of the majority class (i.e., with the highest intensity) are the parameters produced from the Composer® software that had the highest precision and can be used to estimate crude oil properties. The DBE values presented lower intermediate precision limit values (0.04%) than the assigned class values (0.4%). According to CV and PCA, ESI(+) was more precise for crude oil A (83% precision) and ESI(−) for crude oil B (84% precision).