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.
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.
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
•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.
Qualitative differentiation between natural and enriched chicken eggs through omega (ω) 3 fatty acid profiles by capillary zone electrophoresis (CZE) under direct UV detection at 200 nm is proposed. ...The electrolyte background consisted of 12.0 mmol L−1 tetraborate buffer (pH 9.2) mixed with 12.0 mmol L−1 Brij 35, 17% acetonitrile (ACN) and 33% methanol (MeOH). Omega 3 fatty acid profile in chicken egg samples were analyzed by CZE system and confirmed by single-quadrupole mass spectrometry with an electrospray ionization probe set to negative ionization mode after sample preparation by the Folch method. The results showed that ω fatty acid profiles analyzed by the CZE approach can be used to chemical markers to monitor fraud, presenting simplicity, short analysis time (10 min) and low cost as advantages.
Conjugated linoleic acid (CLA) has been the subject of numerous studies in recent decades because of its associated health benefits. CLA is an intermediate product of the biohydrogenation pathway of ...linoleic acid (LA) in bacteria. Several bacterial species capable of efficiently converting LA into CLA have been widely reported in the literature, among them Lactobacillus delbrueckii subsp.
LBP UFSC 2230. Over the last few years, a multicomponent enzymatic system consisting of three enzymes involved in the biohydrogenation process of LA has been proposed. Sequencing the genome of L. delbrueckii subsp.
LBP UFSC 2230 revealed only one gene capable of encoding an oleate hydratase (OleH), unlike the presence of multiple genes typically found in similar strains. This study investigated the biological effect of the OleH enzyme of L. delbrueckii subsp.
LBP UFSC 2230 on the hydration of LA and dehydration of ricinoleic acid (RA) and its possible role in the production of CLA. The OleH was cloned, expressed, purified, and characterized. Fatty acid measurements were made by an internal standard method using a gas chromatography-coupled flame ionization detector (GC-FID) system. It was found that the enzyme is a hydratase/dehydratase, leading to a reversible transformation between LA and RA. In addition, the results showed that L. delbrueckii subsp.
LBP UFSC 2230 OleH protein plays a role in stress tolerance in Escherichia coli. In conclusion, the OleH of L. delbrueckii subsp.
LBP UFSC 2230 catalyzes the initial stage of saturation metabolism of LA, although it has not converted the substrates directly into CLA.
This study provides insight into the enzymatic mechanism of CLA synthesis in L. delbrueckii subsp.
and broadens our understanding of the bioconversion of LA and RA by OleH. The impact of OleH on the production of the
9,
11 CLA isomer and stress tolerance by E. coli has been assisted. The results provide an understanding of the factors which influence OleH activity. L. delbrueckii subsp.
LBP UFSC 2230 OleH presented two putative fatty acid-binding sites. Recombinant OleH catalyzed both LA hydration and RA dehydration. OleH was shown to play a role in bacterial growth performance in the presence of LA.
•Alternative method for determination of milk adulteration by whey.•Quality control tests in the field of dairy industry.•Fast, simple and ecofriendly separation method.
Adulteration of milk with ...whey is difficult to detect because these two have similar physical and chemical characteristics. The traditional methodologies to monitor this fraud are based on the analysis of caseinomacropeptide. The present study proposes a new approach to detect and quantify this fraud using the fatty acid profiles of milk and whey. Fatty acids C14:0, C16:0, C18:0, C18:1, C18:2 and C18:3 were selected by gas chromatography associated with discriminant analysis to differentiate milk and whey, as they are present in quite different amounts. These six fatty acids were quantified within a short time by capillary zone electrophoresis in a set of adulterated milk samples. The correlation coefficient between the true values of whey addition and the experimental values obtained by this technique was 0.973. The technique is thus useful for the evaluation of milk adulteration with whey, contributing to the quality control of milk in the dairy industry.
•bvFTD group presented an impairment of amino acid metabolism compared to controls.•bvFTD patients showed changes in translation process compared to controls.•bvFTD group did not present different ...metabolites compared to AD group.
Frontotemporal dementia (FTD) is a neurodegenerative disorder characterized by progressive impairment in behavior, executive function, and language. The behavioral variant (bvFTD) is the most clinical common form and requires differential diagnosis with atypical Alzheimer’s disease (AD) cases. This study aimed to investigate the plasma metabolite profile of patients with bvFTD compared to AD patients and cognitively healthy individuals using gas chromatography coupled to mass spectrometry (GCMS). This study included nine patients with bvFTD, 17 with AD and 15 cognitively healthy controls (training set), whose data were validated on a testing set (eight bvFTD, 14 AD and ten controls). The metabolites were detected by GCMS. A tendency towards a reduction in the levels of palmitoleic, oleic and lauric acids was found in the bvFTD group compared to the AD group; however, no significance after multiple comparison correction was observed. However, bvFTD group showed reduced levels of creatinine, glycine, tryptophan, uric acid, hypoxanthine, serine, valine, threonine, isoleucine, homoserine, methionine, glutamic acid, capric acid, tartronic acid, fumaric acid, and myo-inositol, metabolites related to glycine/serine/threonine, alanine/aspartate/glutamate pathways and aminoacyl-tRNA biosynthesis, when compared to controls. The data suggest that bvFTD patients may present an impairment of amino acid metabolism and the translation process. This pioneering study on bvFTD and its plasma metabolomic signature can be useful to provide new ideas about pathophysiological mechanisms, as well as guide more robust studies in search of possible biomarkers for the diagnosis of this important dementia.
In the present work, an alternative method for trans fatty acids (TFA) analysis with direct UV detection using capillary zone electrophoresis (CZE-UV) is proposed. The background electrolyte used ...consisted of 12.0 mmol L−1 of tetraborate buffer, 12.0 mmol L−1 of Brij 35, 33% methanol and 17% acetonitrile. Trans fatty acids in different samples such as butter toffee, cake mix, stuffed wafers, chocolate and a mix for Brazilian cheese bread were successfully quantified within an analysis time of 13 min, taking into account the statistical approach based on response factor calculation using C19:1 (nonadecaenoic acid) as internal standard. The statistical comparison between CZE-UV and the classical GC method for the analyzed samples did not present significant differences within the 95% confidence interval.
•Rapid method for trans fatty acids analysis by CZE-UV.•Alternative methodology with improvement in throughput analysis.•Low cost by analysis and absence of specific separation column.•Very useful method for screening analysis in complex samples.
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