The present article revisits the recent articles where capillary electromigration techniques have been applied to study numerous phytochemicals between the years 2018 and 2021. The manuscript has ...been divided according to the different separation methods used, and the main aspects of each application have been briefly discussed, including sample preparation, advantages and disadvantages of the developed methods, problems encountered during the process and ways to solve them.
•Methods in accordance with green chemistry.•Ionic liquids and nanoparticles used in capillary electrophoresis.•Association of capillary electrophoresis with chemometric modeling techniques.
Ruminant milk is the lead source of conjugated linoleic acid (CLA) in the human diet, with cis-9, trans-11 CLA being the major among all. Small amounts of trans-10, cis-12 CLA are also found in ...synthetic supplements. Since both isomers are biologically active with potential health benefits, there is great interest in quantifying them for quality control routines. An alternative method for the analysis of the aforementioned CLAs by fast gas chromatography (GC) is discussed in the present study. The fatty acid methyl ester mixture obtained by alkaline catalysis was injected into a GC equipped with a flame ionization detector (FID) and fitted with an ionic liquid SLB-IL111 chromatographic column (15 m × 0.10 mm × 0.08 µm). Separation was achieved in less than 5 min using a 168 °C isotherm run. Both CLA isomers were quantified by using of single point standard addition statistical approach. Results were contested to those obtained using the recommended 100 m long CP-Sil88 capillary column and none evidence of significant differences was found within 95% confidence interval. Therefore, the proposed method could be valuable to focused regulatory routines of large numbers of samples with greater analytical frequency.
In this work, blends of olive and soybean oils were analyzed by near-infrared spectroscopy (NIR), mid-infrared (MIR), and Raman techniques to evaluate adulterations in olive oils. A representative ...group of different commercial brands of soybean oil and extra-virgin olive oil were analyzed by gas chromatography with flame ionization detector in order to explore the chemical similarity and composition of the fatty acid (FA) profile. Two stock solutions were prepared, one produced from a mixture of soybean oils and the other from the mixture of olive oils. From these stock solutions, 60 samples were prepared, simulating adulteration levels of extra-virgin olive oil with soybean oil between 0 and 100 %. It was possible to fit a model able to predict fraud within the interval investigated by partial least squares regression approach, with precision and accuracy values for root mean squared error of prediction of 1.76 (NIR), 4.89 (MIR), and 1.57 (Raman) and coefficient of determination R ² greater than 0.98 for the three techniques. The methodologies demonstrated to be very useful for the quantification of extra-virgin olive oil adulteration with soybean oil, presenting short analysis time, low cost, and absence of sample preparation procedures as main advantages.
Raffinose family oligosaccharides (RFOs) are implicated in plant regulatory mechanisms of abiotic stresses tolerance and, despite their antinutritional proprieties in grain legumes, little ...information is available about the enzymes involved in RFO metabolism in Fabaceae species. In the present study, the systematic survey of legume proteins belonging to five key enzymes involved in the metabolism of RFOs (galactinol synthase, raffinose synthase, stachyose synthase, alpha-galactosidase, and beta-fructofuranosidase) identified 28 coding-genes in Arachis duranensis and 31 in A. ipaënsis. Their phylogenetic relationships, gene structures, protein domains, and chromosome distribution patterns were also determined. Based on the expression profiling of these genes under water deficit treatments, a galactinol synthase candidate gene (AdGolS3) was identified in A. duranensis. Transgenic Arabidopsis plants overexpressing AdGolS3 exhibited increased levels of raffinose and reduced stress symptoms under drought, osmotic, and salt stresses. Metabolite and expression profiling suggested that AdGolS3 overexpression was associated with fewer metabolic perturbations under drought stress, together with better protection against oxidative damage. Overall, this study enabled the identification of a promising GolS candidate gene for metabolic engineering of sugars to improve abiotic stress tolerance in crops, whilst also contributing to the understanding of RFO metabolism in legume species.
A review taking into account the literature reports covering 20 years of fatty acid analysis by capillary electrophoresis is presented. This paper describes the evolution of fatty acid analysis using ...different CE modes such as capillary zone electrophoresis, non-aqueous capillary electrophoresis, micellar electrokinetic capillary chromatography and microemulsion electrokinetic chromatography employing different detection systems, such as ultraviolet-visible, capacitively coupled contactless conductivity, laser-induced fluorescence and mass spectrometry. In summary, the present review signals that CE seems to be an interesting analytical separation technique that is very useful for screening analysis or quantification of the usual fatty acids present in different matrices, offering short analysis times and a simple sample preparation step as inherent advantages in comparison with the classical methodology, making it a separation technique that is very attractive for quality control in industry and government agencies.
•Differentiation of conventional and ω3 enriched eggs by Raman spectra and PLS-DA.•Fatty acids profiles were analyzed by gas chromatography.•PLS-DA model discriminated among samples with almost 100% ...of success rate.•Raman modes that most contributed to the discrimination were identified.•Uncertainty estimation of the predicted values by bootstrap resampling.
This work developed an analytical method to differentiate conventional and omega-3 fat acids enriched eggs by Raman spectroscopy and multivariate supervised classification with Partial Least Squares Discriminant Analysis (PLS-DA). Forty samples of enriched eggs and forty samples of different types of common eggs from different batches were used to build the model. Firstly, gas chromatography was employed to analyze fatty acid profiles in egg samples. Raman spectra of the yolk extracts were recorded in the range from 3100 to 990 cm−1. PLS-DA model was able to correctly classify samples with nearly 100% success rate. This model was validated estimating appropriate figures of merit. Predictions uncertainties were also estimated by bootstrap resampling. The most discriminant Raman modes were identified based on VIP (variables importance in projection) scores. This method has potential to assist food industries and regulatory agencies for food quality control, allowing detecting frauds and enabling faster and reliable analyzes.
The characterization of the lipid profiles of oils extracted from the kernel of seeds and nuts of peanut (Arachis hypogaea), babassu (Attalea speciosa), coconut (Cocos nucifera), castor (Ricinus ...communis) and grape (Vitis vinifera) was performed by using Raman spectroscopy and gas chromatography with flame ionization detector (GC-FID). Chromatographic analyses showed that coconut and babassu oils are composed essentially by saturated fatty acids (SFA), whereas the others are composed mainly by unsaturated fatty acids (UFA). The comparison of commercial and homemade castor oils showed the former have a lower level of ricinoleic acid at ca. 58%. Spectroscopic analyses of three distinct castor oils showed their profiles could be differentiated by marker features ascribed to carbonyl modes which were correlated with storage time. The comparison between the Raman spectra of standard samples of fatty acids with the samples of oils allowed the assignment of the spectroscopic features and the characterization of marker bands for the degree of unsaturation.
Bottled butter is a handmade product typical of Brazil with similar features to the Indian ghee and the butter oil. The ingredient presents in its chemical composition mostly even and uneven ...unbranched carbonic chain fatty acids (FAs). The importance of lipids on human nutrition and quality control of fat-containing foods is well-established, therefore, we present an alternative method for the analysis of FAs by capillary zone electrophoresis with indirect UV detection (CZE-UV) using a simple saponification procedure as sample preparation. Exploratory results obtained by CZE-UV were primarily compared to gas chromatography coupled with a flame-ionization detector (GC-FID), and no significant difference within a 95% confidence interval was found. Overall, by the amount of linoleic acid and
trans-
FAs found in bottled butter samples by the validated CZE-UV protocol, we have evidence of tampering in some of the analyzed products, possibly by the addition of vegetable oils previously used in the frying process.
Graphical abstract
•Raman method to quantify tuberculostatic drugs in fixed dose combination tablets.•The four drugs quantification is allowed, in an adequate run time.•No statistical difference between the Raman ...spectroscopy and the HPLC-DAD results.•The method can be employed for manufacture control of pharmaceutical formulations.
Tuberculosis is mainly treated by fixed dose combination therapy containing mainly rifampicin, isoniazid, pyrazinamide and ethambutol. The quality control of these drugs in these formulations is very important because of high incidence of resistance to these drugs. Most of the analytical methods developed for the quantification analyze these drugs individually and they are laborious, costly, and time consuming. The present work aims at developing an alternative analytical method addressing these limitations of the traditional methods A Raman spectroscopic method was developed to simultaneously estimate all these four first line antituberculosis drugs. This method has addressed all these limitations of traditional methods as it was very simple, rapid and cost effective. Calibration and validation samples of these drugs were prepared with a wider range and analyzed by both Raman and HPLC. Various figures of merit were determined for the developed method to evaluate the efficacy and quality of the method. Partial Least Squares regression (PLS) approach was used in Raman spectroscopic method to quantify the drugs. Correlation graphs and paired t test were used to compare these two analytical. Based on the results obtained, Raman spectroscopic method was found to be an efficient alternative for the simultaneous estimation of rifampicin, isoniazid, pyrazinamide and ethambutol. These results also indicate that the developed Raman method can be used as a screening technique in the quality control of fixed dose combination products for the therapy of tuberculosis.
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