A rapid method for simultaneous quantification of 13 sugars and sugar alcohols in food products by UPLC-ELSD

Implementation of gas chromatography tandem mass spectrometry for the analysis of six high boiling point polyhydric alcohols in cosmetics and toothpaste based on precolumn derivatization

Based on precolumn derivatization, an analytical method has been developed for the determination of six high boiling point polyhydric alcohols (HBPAs, b.p. > 300 ℃) in cosmetics and toothpaste, including erythritol, xylitol, Pro-Xylane-S, inositol, mannitol, and sorbitol. The water dispersion and oil in water samples were extracted by distilled water. The water in oil sample was firstly pre-dispersed with acetone, and then extracted by distilled water. The extract was concentrated to dry under nitrogen, and derivatized with acetic anhydride under the dispersion and catalysis of anhydrous pyridine. The derivatives were detected by gas chromatography-tandem mass spectrometry in the selected reaction monitoring mode, and quantified using arabinitol as internal standard. The experimental conditions such as the selection of columns, extraction procedures, and derivative conditions were optimized. This method was properly validated under the optimized conditions, and obtained excellent analytical features. Specifically, the correlation coefficients in the range of 0.02 ∼ 0.5 mg/L all exceed 0.992. The method limits of detection and quantification were 0.25 and 0.8 mg/kg, respectively. The average recoveries in toothpaste, cosmetics with oil in water and water in oil were 81.8 ∼ 107.1 %, with the relative standard deviation were 3.1 ∼ 7.2 %. The established method was successfully applied to commercial samples of different matrices, showing the advantages of simplicity, sensitivity, and good reproducibility, and can be used for the determination of HBPAs in cosmetics and toothpaste. The proposed methodology solves the problem that there is no detection method for HBPAs in cosmetics.

Comprehensive quality assessment of 296 sweetpotato core germplasm in China: A quantitative and qualitative analysis

The potential for improving sweetpotato quality remains underutilized due to a lack of comprehensive quality data on germplasm resources. This study evaluated 296 core germplasms, revealing significant phenotypic diversity across 24 quality traits in both stem tips and roots. Landraces had higher sugar content in roots, while wild relatives showed increased total flavonoid and phenol contents. Accessions with red-orange flesh were rich in sugars and carotenoids, whereas those with purple flesh had higher dry matter, flavonoids, and phenols. The accessions were classified into three clusters: high sugars and carotenoids, high phenolic compounds, and high starch. A comprehensive quality scoring model identified SP286 and SP192 as superior for stem tips and roots, respectively. Near-infrared spectroscopy, combined with a random forest algorithm, enabled rapid screening of superior germplasm, achieving prediction accuracies of 97 % for stem tips and 98 % for roots. These findings offer valuable resources and high-throughput models for enhancing sweetpotato quality.

Comparison of three HPLC analytical methods: ELSD, RID, and UVD for the analysis of xylitol in foods

In this study, xylitol, a common sweetener and sucrose substitute in low-calorie foods, was quantified by high-performance liquid chromatography (HPLC). During the establishment of the analytical method, three representative detection approaches, ultraviolet detector (UVD), evaporative light scattering detector, and refractive index detector, were compared and applied to determine the xylitol content in various foods distributed in Korea. The results were compared for method validation, measurement uncertainty, and applicability. As a result, HPLC-UVD showed the lowest limit of detection (0.01 mg/L) and limit of quantification (0.04 mg/L) among the three methods. It showed a low range of relative expanded uncertainty (1.12-3.98%) and could quantify xylitol in the wide range of the samples, even trace amounts of xylitol. Therefore, a total of 160 food items, including chewing gum, candy, beverage, tea, other processed products, and beverage base, were applied with three replicates by the proposed HPLC-UVD method.

A novel and sensitive method for simultaneous determination of 6 low-calorie bulk sweeteners by HPLC-ELSD

A novel and sensitive method for the simultaneous analysis of six low-calorie bulk sweeteners (D-allulose, D-tagatose, D-mannitol, mycose, palatinose, and erythritol) without derivatisation was developed using high-performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD). Chromatographic separations were carried out on a Zorbax Original NH2 (5 μm particle size, 250 mm×4.60 mm id, 70 Å) column with flow rate gradient elution with acetonitrile: water (80:20, v/v). Drift tube temperature was set at 50 ℃, the nebuliser carrier gas flow rate was 1.0 mL·min-1, and nitrogen pressure was regulated to 276 kPa with gain:3. The regression equation showed good linearity (R2 = 0.9985-0.9998) for all six low-calorie bulk sweeteners in the tested range (0.060-0.60 mg·mL-1). The limits of detection (LOD) for the six low-calorie bulk sweeteners ranged from 0.02 to 0.06 mg·mL-1. The proposed HPLC-ELSD method was validated for the quantification of the low-calorie bulk sweeteners in 14 types of foods, and the results were satisfactory. In addition, the results showed that the number of sweeteners in each food product varied. The presence of multiple low-calorie bulk sweeteners in certain foods is interesting. This method is successful in monitoring low-calorie bulk sweeteners in food.

Re-evaluation of erythritol (E 968) as a food additive

This opinion addresses the re-evaluation of erythritol (E 968) as food additive and an application for its exemption from the laxative warning label requirement as established under Regulation (EU) No 1169/2011. Erythritol is a polyol obtained by fermentation with Moniliella pollinis BC or Moniliella megachiliensis KW3-6, followed by purifications and drying. Erythritol is readily and dose-dependently absorbed in humans and can be metabolised to erythronate to a small extent. Erythritol is then excreted unchanged in the urine. It does not raise concerns regarding genotoxicity. The dataset evaluated consisted of human interventional studies. The Panel considered that erythritol has the potential to cause diarrhoea in humans, which was considered adverse because its potential association with electrolyte and water imbalance. The lower bound of the range of no observed adverse effect levels (NOAELs) for diarrhoea of 0.5 g/kg body weight (bw) was identified as reference point. The Panel considered appropriate to set a numerical acceptable daily intake (ADI) at the level of the reference point. An ADI of 0.5 g/kg bw per day was considered by the Panel to be protective for the immediate laxative effect as well as potential chronic effects, secondary to diarrhoea. The highest mean and 95th percentile chronic exposure was in children (742 mg/kg bw per day) and adolescents (1532 mg/kg bw per day). Acute exposure was maximally 3531 mg/kg bw per meal for children at the 99th percentile. Overall, the Panel considered both dietary exposure assessments an overestimation. The Panel concluded that the exposure estimates for both acute and chronic dietary exposure to erythritol (E 968) were above the ADI, indicating that individuals with high intake may be at risk of experiencing adverse effects after single and repeated exposure. Concerning the new application, the Panel concluded that the available data do not support the proposal for exemption.

A novel approach for lactose determination in cow's milk exploiting smartphone-based digital-image photometry

Lactose, the main carbohydrate in cow's milk, may cause health problems for consumers with intolerance. Lactose determination in milk is hindered by the matrix complexity and lack of chromophore groups. Chromatography, volumetric, and spectrophotometric approaches involving chemical derivatization are time-consuming and require laborious sample preparation, which is incompatible with the high analytical demand. In this context, a novel approach is presented for lactose determination in milk exploiting smartphone-based digital-image photometry. It was based on a modification of the Benedict's method, involving formation of the violet Cu(I)/2,2'-biquinoline-4,4'-dicarboxylate (BCA) complex instead of the copper(I) oxide precipitate, aiming at improvement of sensitivity and precision. Sample pretreatment and analyte derivatization were performed in Eppendorf tubes with minimal reagent amounts and a smartphone camera was used for image acquisition under controlled conditions. Measurements were based on the RGB color system, taking channel G as the analytical response because of the complementarity with the color of the complex. Under the optimized conditions, the proposed procedure yielded a linear response up to 20 mg L-1 (r = 0.999), with a limit of detection of 1.5 mg L-1, which is compatible with determination of lactose in milk and dairy products categorized with low content of the sugar. The procedure takes less than 10 min, with a coefficient of variation of 3.0% (n = 12) and consumes as low as 160 μg Cu and 430 μg BCA per determination, thus being a more practical, fast, cost-effective, and environmental friendly analytical method.

Determination of sugars and sugar alcohols in infant formula by high performance liquid chromatography with evaporative light-scattering detector

A method was established for the simultaneous determination of five sugars (fructose, glucose, sucrose, lactose, maltose) and five sugar alcohols (erythritol, xylitol, sorbitol, mannitol, maltitol) in infant formula by high performance liquid chromatography-evaporative light scattering detector. After the samples were extracted with acetonitrile-water solution, precipitated by acetic acid, and purified with solid phase extraction cartridge, ALLChrom Rocksil Carbohydrate ES column was adopted for separation, and isocratic elution was conducted at the flow rate of 1.0 mL/min with acetonitrile-0.04 % ammonia solution as the mobile phase. The analytes were detected by an evaporative light-scattering detector, and quantified by external standard method. The linear ranges of the 10 components were 0.04-4.0 g/L with the correlation coefficients greater than 0.999, and the limits of quantification (S/N = 10) of the method were 0.08-0.4 g/100 g. The relative standard deviation of the lactose parallel samples reached 1.29 %, and the recoveries of the other 9 components ranged from 80.4 % to 99.4 % with the relative standard deviation of 2.8 %-7.1 %. The method performs well in sensitivity and separation, which is suitable for the simultaneous quantitative determination of sugars and sugar alcohols in infant formula.

Development of Green UV-Vis Method for Direct Determination of Total Sugars in the Aqueous Extract of Teff (Eragrostis tef (Zuccagni) Trotter) Grains and Other Cereals

There is no ultraviolet visible (UV-Vis) spectrophotometric method for the direct determination of total sugars in the aqueous extract of teff grain samples. Therefore, the objective of this study was to develop a green UV-Vis spectrophotometric method to determine total sugars in the aqueous extract of white teff, brown teff, white rice, and red wheat grain samples. The calibration curve was established in the range of 20.11-7,907 mg/L using sucrose as a standard with R ² = 0.9996. The limit of detection and limit of quantification were 4.4 and 14.6 mg/L, respectively. The relative standard deviation (6.9%) of the method for the sucrose standard was within the acceptable range indicating that the method is precise. The amount of total sugars determined in the white teff (5.48-9.44% (w/w), brown teff (6.17-10.32% (w/w)), white rice (3.19% (w/w)), and red wheat (9.22% (w/w)) grain samples was comparable with other reported cereal grains. Furthermore, the accuracy of the developed analytical method was also evaluated by spiking the known amount of the sucrose standard solution to the white teff, brown teff, white rice, and red wheat sample extracts, and percentage recoveries found were in the acceptable range (85 ± 2 - 105 ± 4%) with an average recovery of 93%, confirming that the new green method is quantitatively reproducible. Hence, a fast, simple, inexpensive, widely used, selective, sensitive, precise, and accurate green UV-Vis method was developed and validated for the direct determination of total sugars in the aqueous extract of teff, white rice, and red wheat grain samples.

Nutritional Comparison of Sacha Inchi (Plukenetia volubilis) Residue with Edible Seeds and Nuts in Taiwan: A Chromatographic and Spectroscopic Study

Sacha inchi is a source of quality commercial oil in Taiwan. Oil extraction results in sacha inchi residue have not been utilized and not much investigated. Different edible seeds and nuts have different levels of nutrients. This study aims (a) to determine the oil, moisture, ash, protein, carbohydrate, type of fatty acid, resveratrol, and type of sugar in edible seeds and nuts, including sacha inchi residue, and (b) to determine the model to predict the five macronutrients using NIR spectroscopy. The samples used were candlenut, peanut, sesame, sunflower, sacha inchi residue, and black bean. Determination was conducted using NIR spectroscopy, NMR spectroscopy, LC-MS/MS, and HPLC-ELSD. NIR spectroscopy prediction results show that candlenut is rich in oil, and sacha inchi residue is rich in minerals, protein, and moisture. The correct prediction model for oil and moisture is principal component regression, while partial least squares are for ash, protein, and carbohydrates. NMR spectroscopy results showed that all samples were rich in polyunsaturated fatty acids. Sacha inchi residue is rich in omega 3. LC-MS/MS results showed that all samples contained resveratrol, and its highest level was found in sesame. HPLC-ELSD results showed eight types of sugars in the samples. High sucrose was found in sacha inchi residue, sunflower, sesame, and candlenut. The results are expected to provide information on nutrient levels in seeds and nuts to consumers and people who deal with nutrition. Also, results are expected to increase the economic value of sacha inchi residue as a source of diversification of food products in Taiwan.

Comparative study for analysis of carbohydrates in biological samples

This work presents a comparative study for the analysis of carbohydrates for four common chromatographic methods, each coupled to mass spectrometry. Supercritical fluid chromatography (SFC), hydrophilic interaction liquid chromatography (HILIC), reversed-phase liquid chromatography (RP-LC) and gas chromatography (GC) with detection by triple quadrupole mass spectrometer (QqQ-MS) are compared. It is shown that gas chromatography and reversed-phase liquid chromatography, each after derivatisation, are superior to the other two methods in terms of separation performance. Furthermore, comparing the different working modes of the mass spectrometer, it can be determined that a targeted analysis, i.e. moving from full scan to single ion monitoring (SIM) and multiple reaction monitoring (MRM), results in an improvement in the sensitivity as well as the repeatability of the method, which has deficiencies especially in the analysis using HILIC. Overall, RP-LC-MS in MRM after derivatisation with 1-phenyl-3-methyl-5-pyrazolone (PMP) proved to be the most suitable method in terms of separation performance, sensitivity and repeatability for the analysis of monosaccharides. Detection limits in the nanomolar range were achieved, which corresponds to a mass concentration in the low µg/L range. The applicability of this method to different biological samples was investigated with various herbal liquors, pectins and a human glycoprotein.

Analysis of Free Sugars, Organic Acids, and Fatty Acids of Wood Apple (Limonia acidissima L.) Fruit Pulp

Wood apple (Limonia acidissima L.) is an underutilized, fruit-yielding tree that is native to India and Sri Lanka. Wood apple trees are also cultivated in India, Sri Lanka, Bangladesh, Myanmar, Thailand, Malaysia, Vietnam, Kampuchea, Laos, and Indonesia for delicious fruits and medicinal purposes. The major objective of the present work was the analysis of the nutritional status of wood apple fruit pulp.The fruits are rich in total carbohydrates (24.74 ± 0.19%), total proteins (9.30 ± 0.16%), oil (0.99 ± 0.01%), fiber (3.32 ± 0.02%), and ash (2.73 ± 0.12%). Further analysis and quantification of free sugars, organic acids, and fatty acid methyl esters were carried out by using high-performance liquid chromatography (HPLC) and gas chromatographic (GC) methods. In total, five sugars and nine organic acids were detected and quantified. The predominant sugars were fructose (16.40 ± 0.23%) and glucose (14.23 ± 0.10%), whereas the predominant organic acids were D-tartaric (4.01 ± 0.03%), ascorbic (4.51 ± 0.05%), and citric acid (4.27 ± 0.04%). The oil content of fruit pulp was 0.99 ± 0.01% and GC-MS analysis revealed that, it comprise of 16 fatty acid methyl esters. The percentage of saturated fatty acids were 32.17 ± 0.35%, that includes palmitic (18.52 ± 0.12%) and stearic acids (9.02 ± 0.08%), whereas, the unsaturated fatty acids were 51.98 ± 0.94%, including oleic acid (23.89 ± 0.06%), α-linolenic acid (16.55 ± 0.26%), linoleic acid (10.02 ± 0.43%), and vaccenic acid (1.78 ± 0.23%).

Enhanced separation and analysis of low abundant soy proteins by dual washing extraction process

Soybean seeds provide a rich source of proteins, fats, carbohydrates, and micronutrients. Extraction and analysis of low abundant soybean seed proteins are challenging because of its complex seed composition. For characterizing various proteins, it is paramount to remove the other interfering components, primarily oils, and carbohydrates. In the present study, we used a sequential dual washing process initially with hexane to remove oil and non-polar interferences, followed by 80% ethanol washing to remove about 60% of the total soluble sugars. The extracted soluble sugars were quantified using a newly developed and validated high-performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD). This newly developed combined washings process significantly enhanced the separation of both low molecular weight and low abundant proteins using 1D (one dimensional)- and 2D (two dimensional) gel electrophoresis. The separated proteins were trypsinized and analyzed by using Bruker amazon speed ion trap mass spectrometer equipped with an ESI source. This combined washing process allowed the identification of 18 additional low abundant soy proteins as compared to the simple hexane washed samples. This purification process will allow researchers to identify and investigate the role of low molecular weight and low abundant proteins as it relates to plant functions, nutrition, and health.

Maltitol: Analytical Determination Methods, Applications in the Food Industry, Metabolism and Health Impacts

Bulk sweetener maltitol belongs to the polyols family and there have been several dietary applications in the past few years, during which the food industry has used it in many food products: bakery and dairy products, chocolate, sweets. This review paper addresses and discusses in detail the most relevant aspects concerning the analytical methods employed to determine maltitol's food safety and industry applications, its metabolism and its impacts on human health. According to our main research outcome, we can assume that maltitol at lower doses poses little risk to humans and is a good alternative to using sucrose. However, it causes diarrhoea and foetus complications at high doses. Regarding its determination, high-performance liquid chromatography proved the primary method in various food matrices. The future role of maltitol in the food industry is likely to become more relevant as processors seek alternative sweeteners in product formulation without compromising health.

Validation of a sensitive high performance liquid chromatography tandem mass spectrometric method for measuring carbohydrates in aerosol samples

Carbohydrates (such as levoglucosan) are a class of important water-soluble organic compounds in atmosphere. In this study, a high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) was applied to characterize carbohydrates in aerosol particles. Since carbohydrate was a kind of compound with low response in mass spectrometry, the conventional HPLC-MS/MS method was not sensitive enough to determine it. When acetate acid was added into mobile phase as buffer, the transition of [M+CH₃COO]^-→[M-H]^- could be selected as the quantification ions. In the range from 1.0 μg L^-1 to 20 μg mL^-1, the coefficients of regression (r²) were more than 0.990, and relative standard deviations (RSD) for replicated injections were lower than 2%. The limit of detection (LOD) and quantification (LOQ) were lower than 2.5 ng L^-1 and 10 ng L^-1, respectively. The precision and accuracy were examined by spiked samples at three different concentration levels (10 μg L^-1, 100 μg L^-1, and 500 μg L^-1) in five replicates. Recovery ratios ranged from 85% to 115% with RSD lower than 16%. Matrix effects of different carbohydrates ranged from 62% to 120%. The most sensitive HPLC-MS/MS method was developed and validated to analyze 40 aerosol samples successfully. The carbohydrates including three sugar alcohols (threitol, arabitol and sorbitol), one monosaccharide sugar (inositol), two disaccharides (sucrose, trehalose), one anhydrosugar (levoglucosan) and one 2-methyltetrols (2-Methylbutane-1,2,3,4-tretraol) were successfully quantified.

Determination of bisphenol analogues in food-contact plastics using diode array detector, charged aerosol detector and evaporative light-scattering detector

Freshness protection packages and preservative films are widely used food-contact plastic made of polyethylene. Diode array detector (DAD), charged aerosol detector (CAD) and evaporative light-scattering detector (ELSD) were evaluated for determination of 6 bisphenols (bisphenol A, bisphenol S, bisphenol F, bisphenol B, bisphenol AF and tetrabromobisphenol A.) in polyethylene. DAD presented better parameters including limit of quantification (LOQs) ranging from 0.05 to 0.5 μg/g with relative standard deviations (RSDs, n = 5) lower than 1% at two concentration levels. CAD and ELSD are universal detectors with relative consistent response parameters for different analogues which have potential application by using single calibrant for quantification of multiple analytes. Matrix effects were barely observed on three detectors. Samples of freshness protection packages and preservative films were further analyzed and preliminary profiles of bisphenols in products from Beijing market was obtained. Bisphenol S have become most abundant analogue instead of bisphenol A in investigated products.

Compositional Analysis of Non-Polar and Polar Metabolites in 14 Soybeans Using Spectroscopy and Chromatography Tools

There has been significant interest in soybean oil, fatty acid, and sugar composition to develop new value-added soybean products. Thus, compositional analysis is critical for developing value-added soybeans. In the present study, we showed simple screening tools (near infrared spectroscopy (NIR) and high-performance thin layer chromatography (HPTLC)) coupled with multivariate analysis for the sample classification of 14 soybeans as a proof-of-concept. We further determined major non-polar and polar metabolites responsible for differences between different soybeans using gas and ion chromatography. These differences in soybean profiles were attributed to lower levels of total oil content in wild soybeans (~9%) versus cultivated soybeans (16%–22%). In addition, higher levels of linolenic acid (~17%) and stachyose (~53%) were determined in wild type, whereas higher levels of oleic acid (~19%) and sucrose (~59%) were detected in cultivated soybeans. Interestingly, one cultivated soybean had a desirable sugar profile with a high amount of sucrose (86%) and a low abundance of stachyose (9%). The correlation studies showed a positive correlation between oil and soluble sugars (R² = 0.80) and negative correlations between methyl linolenate and soluble sugars (R² = −0.79), oil (R² = −0.94), and methyl oleate (R² = −0.94) content. Both polar and non-polar metabolites showed significant differences in wild and cultivated soybeans.

Atomistic mechanisms underlying the activation of the G protein-coupled sweet receptor heterodimer by sugar alcohol recognition

The human T1R2-T1R3 sweet taste receptor (STR) plays an important role in recognizing various low-molecular-weight sweet-tasting sugars and proteins, resulting in the release of intracellular heterotrimeric G protein that in turn leads to the sweet taste perception. Xylitol and sorbitol, which are naturally occurring sugar alcohols (polyols) found in many fruits and vegetables, exhibit the potential caries-reducing effect and are widely used for diabetic patients as low-calorie sweeteners. In the present study, computational tools were applied to investigate the structural details of binary complexes formed between these two polyols and the T1R2-T1R3 heterodimeric STR. Principal component analysis revealed that the Venus flytrap domain (VFD) of T1R2 monomer was adapted by the induced-fit mechanism to accommodate the focused polyols, in which α-helical residues 233-268 moved significantly closer to stabilize ligands. This finding likely suggested that these structural transformations might be the important mechanisms underlying polyols-STR recognitions. The calculated free energies also supported the VFD of T1R2 monomer as the preferential binding site for such polyols, rather than T1R3 region, in accord with the lower number of accessible water molecules in the T1R2 pocket. The E302 amino acid residue in T1R2 was found to be the important recognition residue for polyols binding through a strongly formed hydrogen bond. Additionally, the binding affinity of xylitol toward the T1R2 monomer was significantly higher than that of sorbitol, making it a sweeter tasting molecule.

A Simple Analysis Method for 4-Deoxy-l-erythro-5-hexoseulose Uronic Acid by HPLC-ELSD with Column for Anion Analysis

4-Deoxy-l- erythro-5-hexoseulose uronic acid (DEH) is a rare deoxy sugar produced from alginate by the action of an exotype alginate lyase. A simple and rapid method for analyzing DEH using high-performance liquid chromatography with evaporative light scattering detection (HPLC-ELSD) was developed in this study. For chromatography, an isocratic elution of ammonium formate buffer including formic acid and a column for anion chromatography were used. In the developed method, DEH was detected at a retention time of 3.038 minutes and limits of detection (signal-noise ratio = 3) and quantification (signal-noise ratio = 10) were 37.5 and 124.9 µg/mL as a sodium DEH, respectively. In addition, separation and detection of alginate unsaturated oligosaccharides were also tested using the method. Within an analysis time of 10 minutes, it was possible to separate and detect unsaturated disaccharide, unsaturated trisaccharide, and unsaturated tetrasaccharide prepared using poly(β-d-mannuronate) lyase and sodium alginate of high mannuronate type. The HPLC-ELSD method established in this study will be applicable for quantitative analysis of DEH and measurement of exotype alginate lyase activity.

Development and validation of HILIC-UHPLC-ELSD methods for determination of sugar alcohols stereoisomers and its application for bioconversion processes of crude glycerin

The recent increase in the production of crude glycerin through the manufacture of biodiesel has imputed a commercial issue, the excess of this raw material in the market and its constant devaluation, which resulted in the need for new technologies for its use. Crude glycerin can be used in biotechnological processes for the production of high value-added compounds. This study presents novel, simple and fast methods based on ultra-high performance liquid chromatography (UHPLC) using evaporative light scattering detection (ELSD) for simultaneous analysis of ten sugar alcohols with a hydrophilic interaction chromatography (HILIC) column. The selected compounds and their possible stereoisomers have major commercial importance and they can be obtained by biotechnological routes. Under optimized conditions, threitol, erythritol, adonitol, xylitol, arabitol, iditol, sorbitol, mannitol, dulcitol and volemitol can be analyzed simultaneously within 15.0 min. The use of different column temperatures was a key parameter to reach the selectivity during the separation of some stereoisomers. Regression equations revealed a good linear relationship (R > 0.995) over the range from 50.0 to 800.0 ng. Limits of detection (LOD) and quantification (LOQ) ranged from 30.0 to 45.0 ng and 50.0-75.0 ng, respectively. The HILIC-UHPLC-ELSD methods showed good precision with low coefficient of variation (CV%) for the intra- and inter-assays experiments (≤ 5.1%) and high repeatability in terms of retention times for each analyte (≤ 0.5%). The accuracy was confirmed with an average recovery ranging from 92.3 to 107.3%. The developed methods employ an analytical technique more accessible and suitable for routine analyzes and have shown to be suitable for simultaneous analysis of sugar alcohols present in crude bioconverted glycerin samples using different classes of microorganisms.

Liquid Chromatography Analysis of Common Nutritional Components, in Feed and Food

Food and feed laboratories share several similarities when facing the implementation of liquid-chromatographic analysis. Using the experience acquired over the years, through application chemistry in food and feed research, selected analytes of relevance for both areas were discussed. This review focused on the common obstacles and peculiarities that each analyte offers (during the sample treatment or the chromatographic separation) throughout the implementation of said methods. A brief description of the techniques which we considered to be more pertinent, commonly used to assay such analytes is provided, including approaches using commonly available detectors (especially in starter labs) as well as mass detection. This manuscript consists of three sections: feed analysis (as the start of the food chain); food destined for human consumption determinations (the end of the food chain); and finally, assays shared by either matrices or laboratories. Analytes discussed consist of both those considered undesirable substances, contaminants, additives, and those related to nutritional quality. Our review is comprised of the examination of polyphenols, capsaicinoids, theobromine and caffeine, cholesterol, mycotoxins, antibiotics, amino acids, triphenylmethane dyes, nitrates/nitrites, ethanol soluble carbohydrates/sugars, organic acids, carotenoids, hydro and liposoluble vitamins. All analytes are currently assayed in our laboratories.

High-throughput simultaneous quantitation of multi-analytes in tobacco by flow injection coupled to high-resolution mass spectrometry

The high-throughput screening by flow injection coupled to high-resolution mass spectrometry (HTS-FIA-HRMS) is a powerful technique that enables the identification of several types of samples in a short period of time, either with qualitative or quantitative purposes. Sensory attributes of tobacco are affected by its chemical composition, and it is very important to quantify multi-analytes in a high-throughput methodology. HTS-FIA-HRMS coupled to multivariate analysis was used to create calibration models for 27 analytes, or group of compounds, of tobacco sensory interest. The models were validated by different approaches, including permutation test to avoid overfitting, evaluation of the equipment repeatability by control samples, reproducibility comparison of results from two different equipment and analysts, and with a blind test analysis. All tests demonstrated a good response to the proposed method. No statistical difference between the errors of both equipment was observed, with less than 7% error from the control samples, and a blind test error between 5.96% and 20.10%. The partial least squares (O-PLS) regression models were applied to 815 samples, and a principal component analysis (PCA) was performed from the predicted concentration values, aiming at the non-supervised classification based on tobacco type. We expect that this proposed methodology shows not only the applicability in tobacco samples, but also demonstrates a guideline to an efficient performance of multi-analytes target analysis using the flow injection mass spectrometry with reliable and robust validation steps.

Liquid Chromatography-Tandem Mass Spectrometry Approach for Determining Glycosidic Linkages

The structural analysis of carbohydrates remains challenging mainly due to the lack of rapid analytical methods able to determine and quantitate glycosidic linkages between the diverse monosaccharides found in natural oligosaccharides and polysaccharides. In this research, we present the first liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based method for the rapid and simultaneous relative quantitation of glycosidic linkages for oligosaccharide and polysaccharide characterization. The method developed employs ultrahigh-performance liquid chromatography coupled with triple quadrupole mass spectrometry (UHPLC/QqQ-MS) analysis performed in multiple reaction monitoring (MRM) mode. A library of 22 glycosidic linkages was built using commercial oligosaccharide standards. Permethylation and hydrolysis conditions along with LC-MS/MS parameters were optimized resulting in a workflow requiring only 50 μg of substrate for the analysis. Samples were homogenized, permethylated, hydrolyzed, and then derivatized with 1-phenyl-3-methyl-5-pyrazolone (PMP) prior to analysis by UHPLC/MRM-MS. Separation by C18 reversed-phase UHPLC along with the simultaneous monitoring of derivatized terminal, linear, bisecting, and trisecting monosaccharide linkages by mass spectrometry is achieved within a 15 min run time. Reproducibility, efficacy, and robustness of the method was demonstrated with galactan ( Lupin) and polysaccharides within food such as whole carrots. The speed and specificity of the method enables its application toward the rapid glycosidic linkage analysis of oligosaccharides and polysaccharides.

Reversed phase ion-pair chromatographic separation of sugar alcohols by complexation with molybdate ion

In this study, we developed a simple and sensitive reversed phase ion-pair chromatographic method for the analysis of C4-C6 sugar alcohols. The method is based on the on-line complexation of sugar alcohols with molybdate ion. The resulting dinuclear anionic complexes can be separated on a reversed-phase C18 column using tetrabutylammonium chloride as an ion-pairing reagent. The mobile phase (pH 3.1) consisted of 0.1 mM disodium molybdate, 1 mM hydrochloric acid and 0.4 mM tetrabutylammonium chloride - 10% v/v methanol. By complexing with molybdate ion, sugar alcohols can be detected by their UV absorption at 247 nm with high resolution and sensitivity. The quantification limits of the examined sugar alcohols calculated at S/N = 10 were 0.1 mM for erythritol and xylitol and 0.01 mM for arabitol, sorbitol, mannitol and dulcitol. The detector response was linear over three orders of magnitude of sugar alcohol concentration. The proposed method was successfully applied to measure sugar alcohols in health drinks, eyedrops and mouthwashes.