The total phenolic content (TPC) and antioxidant capacity have been considered as important quality parameters for plant extracts. In this study, bearberry leaves were regarded as studied subject and ...a reliable method was established to predict the TPC and antioxidant capacity of bearberry leaves. Ultraviolet–visible spectrometry (UV–Vis) and ultra high pressure liquid chromatography coupled to time-of-flight mass spectrometry (UHPLC/Q-TOF-MS) were used to provide spectral fingerprinting and metabolomic profiling. The data obtained (separately and merged) were used to build partial least squares (PLS) regression model. The PLS model built by using ultraviolet–visible spectra provided a satisfactory prediction result. Mid-level data fusion using the scores significantly improved the performance of PLS regression model, the residual predictive deviations (RPDs) for TPC and α, α-diphenyl-β-picrylhydrazyl (DPPH) were 6.258 and 6.699, respectively, showing an excellent predictive ability. This study proved the potential of combination of UV–Vis spectrometry and UHPLC/Q-TOF-MS in the prediction of TPC and antioxidant capacity of plant extracts.
Model built from mid-level data fusion. Display omitted
•UV–Vis can provide good predictions for TPC and antioxidant capacity of bearberry.•The combination of UV–Vis and UPLC-Q/TOF-MS was used for the prediction of TPC and antioxidant capacity of bearberry.•Mid-level data fusion demonstrated to be more efficient on the prediction of the antioxidant capacity than a single technique.
The techniques LC-UV-BPSU and LC-UV-SPE/NMR were applied for the first time in the analysis of açai berry (
Mart.) pulp extracts. Those techniques allowed the identification of twenty-three ...metabolites: Valine (1), citric acid (2), tachioside (3), isotachioside (4),
-guaiacylglycerol (5), syringylglycerol (6), uridine (7), adenosine (8), dimethoxy-1,4-benzoquinone (9), koaburaside (10), protocatechuic acid (11), eurycorymboside B (12), 7',8'-dihydroxy-dihydrodehydroconiferyl alcohol-9-
-
-glucopyranoside (13), orientin (14), homoorientin (15), dihydrokaempferol-3-glucoside (16), isolariciresinol-9'-
-glucopyranoside (17), 5'-methoxyisolariciresinol-9'-
-glucopyranoside (18), cyanidin-3-
-glucoside (19), cyandin-3-
-rutenoside (20), 9,12-octadecadienoic acid (Z,Z)-2-hydroxy-1-(hydroxymethyl) ethyl ester (21), linolenic acid (22), and 1,2-di-
-
-linolenoyl-3-
-galactopyranosyl-sn-glycerol (23). In this plant, compounds 3, 4, 5, 6, 8, 10, 12, 17, 18, 21, and 23 are reported for the first time. All the structures were determined through extensive analyses of 1D and 2D NMR data, mass spectrometry, and comparison with published data. This methodology has proven to be an efficient alternative to the analysis of complex extracts containing a large variety of compounds.
•Cannabidivarin (CBDV) and cannabidibutol (CBDB) are the two major impurities in cannabidiol (CBD) extracted from hemp.•CBDB was isolated and fully characterized for the first time.•A stereoselective ...synthesis was carried out and absolute configuration assigned to natural CBD.•A perfect match of all properties of isolated CBDB and synthesized CBDB was obtained.•A simple and selective HPLC-UV method was developed, validated and applied to ten batches of commercial CBD.
Cannabidiol (CBD), one of the two major active principles present in Cannabis sativa, is gaining great interest among the scientific community for its pharmaceutical, nutraceutical and cosmetic applications. CBD can be prepared either by chemical synthesis or extraction from Cannabis sativa (hemp). The latter is more convenient from several points of view, including environmental and economic, but mainly for the absence of harmful organic solvents generally employed in the chemical synthesis. Although CBD produced by hemp extraction is the most widely employed, it carries two major impurities. The first one is the already known cannabidivarin (CBDV), whereas the second one is supposed to be the butyl analog of CBD with a four-term alkyl side chain. In this work, we report the isolation by semi-preparative liquid chromatography and the unambiguous identification of this second impurity. A comprehensive spectroscopic characterization, including NMR, UV, IR, circular dichroism and high-resolution mass spectrometry (HRMS), was carried out on this natural cannabinoid. In order to confirm its absolute configuration and chemical structure, the stereoisomer (1R,6R) of the supposed cannabinoid was synthesized and the physicochemical and spectroscopic properties, along with the stereochemistry, matched those of the natural isolated molecule. According to the International Nonproprietary Name, we suggested the name of cannabidibutol (CBDB) for this cannabinoid. Lastly, an HPLC-UV method was developed and validated for the qualitative and quantitative determination of CBDV and CBDB in samples of CBD extracted from hemp and produced according to Good Manufacturing Practices regulations for pharmaceutical and cosmetic use.
•Review outlines methodologies used for the determination of vitamin D in milk.•Vitamin D analysis methods in human and bovine milk were included.•Various schemes of sample preparation, ...derivatisation and detection were reviewed.•Summary of all LC methods which has not been written till now is presented
Vitamin D plays an important role in calcium metabolism and affects other metabolic pathways. Despite the intense interest in vitamin D, no comprehensive overview addressing the analysis of vitamin D in milk has been published.
Historically, immunoassay techniques have been mainly used for the routine quantification of vitamin D and its metabolites. However, the greater accuracy and precision of chromatography makes it one of the most important methods in the analysis of vitamin D. The determination of vitamin D and its metabolites by LC–MS is the gold standard for its assessment. LC–MS has unique advantages for vitamin D determination and quantification due to its high sensitivity and specificity.
In this review, the current status of vitamin D and its metabolites analysis in milk, human and bovine, including sample pre-treatment and chromatography analysis, are critically discussed and summarised.
•α-Lactalbumin glycation order: glucose > galacturonic acid > maltotriose.•Absolute quantification of glycation sites was performed by LC-UV-MS.•Lysines K5 and K112 were always the most glycated ...sites.•For all conditions, the protein N-terminal, K58, K62 and K114 were never glycated.
The differences in maximum Maillard glycation extent of proteins incubated with saccharides of different size/charge might be explained by differences in saccharide reactivity towards each protein modification site. Mixtures of α-lactalbumin-glucose (AG), α-lactalbumin-maltotriose (AMTT) or α-lactalbumin-galacturonic acid (AGalA) were incubated for 10 h, reaching a glycation extent of 42, 19 and 30 %, respectively. Glycated protein samples were enzymatically hydrolyzed followed by UPLC-UV-MS determination and quantification of glycation in individual modification sites. On average, around 80 % of protein glycation was recovered as glycated peptides. For all protein-saccharide mixtures, the N-terminal amino group, K58, K62 and K114 were never glycated, whilst K5 and K122 were always the most glycated sites. The glycated sites R10, K79, K93, K94 and K108 found in AGalA, were absent from AG and AMtt. Differences in glycated/non-glycated sites could not explain the differences in total protein glycation between the various samples.
•Fast carbohydrate analysis and micro hydrolysis both processible in 96-well format.•Qualification and quantification of various carbohydrates via UV and MS-detection.•Simplified sample preparation ...and derivatization without extraction and drying.
A fast carbohydrate screening platform processible in 96-well format is described. The method is suitable for the determination of various carbohydrates out of complex mixtures as obtained by acidic hydrolysis of carbohydrates polymers. The chromatographic conditions for an efficient separation (12min) and the derivatization process with 1-phenyl-3-methyl-5-pyrazolone (PMP) were optimized for high resolution separation and simultaneous determination of deoxy-, amino-, anhydro-sugars as well as hexoses, pentoses, dimers, uronic acids and degradation products like furfural and hydroxymethylfurfural (HMF). The potential to quantify with UV- and MS-detector in the same range has been demonstrated for 20 different compounds. Finally, the matrix effects of the hydrolysis were positively evaluated. The micro scale hydrolysis and PMP-derivatization without any extraction or drying steps, both in 96-well format, result in a fast and intuitive sample preparation. In combination with a fast liquid chromatography coupled to UV and electrospray ionization ion trap detection (LC–UV-ESI-MS/MS) for the qualification and quantification of various sugars, dimers and degradation products, this method shows great performance in carbohydrate analysis.
During forced degradation, the intrinsic stability of active pharmaceutical ingredients (APIs) could be determined and possible impurities that would occur during the shelf life of the drug substance ...or the drug product could be estimated. Vildagliptin belongs to relatively new oral antidiabetic drugs named gliptins, inhibiting dipeptidyl peptidase 4 (DPP-4) and prolonging the activities of the endogenous incretin hormones. At the same time, some gliptins were shown as prone to degradation under specific pH and temperature conditions, as well as in the presence of some reactive excipients. Thus, forced degradation of vildagliptin was performed at high temperature in extreme pH and oxidative conditions. Then, selective LC-UV was used for quantitative determination of non-degraded vildagliptin in the presence of its degradation products and for degradation kinetics. Finally, identification of degradation products of vildagliptin was performed using an UHPLC-DAD-MS with positive ESI. Stability of vildagliptin was also examined in the presence of pharmaceutical excipients, using mid-IR and NIR with principal component analysis (PCA). At 70 °C almost complete disintegration of vildagliptin occurred in acidic, basic, and oxidative media. What is more, high degradation of vildagliptin following the pseudo first-order kinetics was observed at room temperature with calculated k values 4.76 × 10−4 s−1, 3.11 × 10−4 s−1, and 1.73 × 10−4 s−1 for oxidative, basic and acidic conditions, respectively. Next, new degradation products of vildagliptin were detected using UHPLC-DAD-MS and their molecular structures were proposed. Three degradants were formed under basic and acidic conditions, and were identified as (3-hydroxytricyclo- 3.3.1.13,7decan-1-yl)aminoacetic acid, 1-{(3-hydroxytricyclo3.3.1.13,7decan-1-yl)aminoacetyl}-pyrrolidine-2-carboxylic acid and its O-methyl ester. The fourth degradant was formed in basic, acidic, and oxidative conditions, and was identified as 1-{(3-hydroxytricyclo3.3.1.13,7-decan-1-yl)aminoacetyl}pyrrolidine-2-carboxamide. When stability of vildagliptin was examined in the presence of four excipients under high temperature and humidity, a visible impact of lactose, mannitol, magnesium stearate, and polyvinylpirrolidone was observed, affecting-NH- and CO groups of the drug. The obtained results (kinetic parameters, interactions with excipients) may serve pharmaceutical industry to prevent chemical changes in final pharmaceutical products containing vildagliptin. Other results (e.g., identification of new degradation products) may serve as a starting point for qualifying new degradants of vildagliptin as it is related to substances in pharmacopoeias.
•The structural impact on anthocyanins’ UV–Vis molar absorptivity was studied;•A quantitative strategy based on the molar relative response factors was proposed;•An online database for 617 ...anthocyanins was developed to support the approach;•Our strategy provided improved quantitative results for anthocyanins in food.
The effects of anthocyanin’s substitution groups on the UV–Vis molar absorptivity were examined by analyzing a group of 31 anthocyanidin/anthocyanin reference standards with ultra-high performance liquid chromatography-diode array detector (UHPLC-DAD). The substitution groups on aglycones were found to associate with molar absorptivity variations, often neglected in anthocyanin quantitation, resulting in significant analytical errors. A simple yet comprehensive strategy based on the molar relative response factors (MRRFs) and a single master reference calibration (i.e., cyanidin-3-glucoside) was proposed to quantify anthocyanins in red cabbage, blueberry, and strawberry samples with improved analytical accuracy. The results indicate this approach provides an effective, inexpensive, and accurate analytical method for anthocyanins in food materials without using individual reference standards. MRRFs of 617 anthocyanins/anthocyanidins were calculated, and the information is freely available at https://BotanicalDC.online/anthocyanin/. This study could be critical to developing new reference methods for anthocyanin analysis and harmonizing results and data from various sources.
Quinoa (Chenopodium quinoa Willd.) grain is gaining great popularity worldwide because it is a rich source of nutrients, bioactive compounds, complete essential amino acids, and high-quality ...proteins. The demand for quinoa-based products is on the rise, which makes them prone to adulteration with less expensive cereals. In this study, we described a rapid and simple procedure for fingerprinting of quinoa grain protein extracts based on the combination of liquid chromatography with ultraviolet absorption diode array detection (LC-UV-DAD) and chemometrics. First, we developed a novel LC-UV-DAD method to obtain distinctive multiwavelength chromatographic profiles of protein extracts from various commercial quinoa grains, which encompass different quinoa varieties sold as black, red, white (from Peru), and royal (white from Bolivia). Then, the components of the LC-UV-DAD fingerprints were deconvoluted by multivariate curve resolution alternating least squares (MCR-ALS), and principal component analysis (PCA) followed by partial least squares discriminant analysis (PLS-DA) were applied to efficiently discriminate the commercial quinoa grains according to their differential composition. The chemometrics-assisted LC-UV-DAD fingerprinting methodology demonstrated its potential to rapidly and reliably discriminate quinoa grains according to the differential composition of their protein extracts and it may be applied in food quality and food fraud control.
•Chemometrics-assisted LC-UV-DAD is proposed for classification of quinoa grains.•Protein extracts of 4 commercial quinoa grains are fingerprinted by LC-UV-DAD.•Fingerprints are deconvoluted by MCR-ALS to obtain representative components.•The differential protein extract composition allows classification by PLS-DA.
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