High-performance Liquid Chromatography-evaporative Light Scattering Detector Research Articles

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.

Carbohydrate-based quality consistency evaluation of Saposhnikoviae Radix

This study aims to evaluate the quality consistency of Saposhnikoviae Radix based on carbohydrates, and explore the potential of carbohydrates as the internal quality control indicators of Saposhnikoviae Radix. The total polysaccharides were quantified by UV-Vis spectrophotometry and the molecular weight range of the polysaccharides was determined by high performance gel-permeation chromatography-evaporative light scattering detection(HPGPC-ELSD). The monosaccharides in polysaccharides and the free monosaccharides were quantified by high performance liquid chromatography-UV detection(HPLC-UV), and the oligosaccharides and fructose were quantified by high performance liquid chromatography-evaporative light scattering detection(HPLC-ELSD). The carbohydrate-based quality of Saposhnikoviae Radix was compared among 45 batches of commercial samples and 13 batches of self-collected samples. The results showed that the molecular weight distribution, monosaccharide composition, oligosaccharide, and free monosaccharide composition were similar in the 58 batches of samples. The average content of total polysaccharides, oligosaccharides, and total free monosaccharides in commercial samples were 39.66, 148.79, and 68.62 mg·g~(-1), respectively. The content showed significant differences among batches, with the highest differences of 3.51, 1.75, and 2.58 times, respectively. The RSD of the relative ratios of monosaccharides in the polysaccharides in commercial samples reached 28%-45%. The average content of total polysaccharides, oligosaccharides, and total free monosaccharides in self-collected samples were 68.07, 145.76, and 42.04 mg·g~(-1), respectively, with the inter-region differences of 2.88, 1.88, and 1.07 times, respectively. The RSD of the relative ratios of monosaccharides in polysaccharides in self-collected samples ranged from 8.2% to 59%. The total polysaccharides and total free monosaccharides in self-collected samples were 1.72 times higher and 1.63 times lower, respectively, than those in commercial samples. The content of oligosaccharides was similar between self-collected samples and commercial samples. To sum up, carbohydrates are one of the material bases for the internal quality consistency of Saposhnikoviae Radix. The qualitative characteristics of polysaccharides and the quantitative characteristics of polysaccharides and oligosaccharides are related to the origin of medicinal materials. Moreover, the quantitative characteristics of polysaccharides and free monosaccharides may be related to the storage conditions. Carbohydrates are potential indicators for the quality control of Saposhnikoviae Radix and deserve attention.

Developing advanced models of biological membranes with hydrogenous and deuterated natural glycerophospholipid mixtures

Cellular membranes are complex systems that consist of hundreds of different lipid species. Their investigation often relies on simple bilayer models including few synthetic lipid species. Glycerophospholipids (GPLs) extracted from cells are a valuable resource to produce advanced models of biological membranes. Here, we present the optimisation of a method previously reported by our team for the extraction and purification of various GPL mixtures from Pichia pastoris. The implementation of an additional purification step by High Performance Liquid Chromatography-Evaporative Light Scattering Detector (HPLC-ELSD) enabled for a better separation of the GPL mixtures from the neutral lipid fraction that includes sterols, and also allowed for the GPLs to be purified according to their different polar headgroups. Pure GPL mixtures at significantly high yields were produced through this approach. For this study, we utilised phoshatidylcholine (PC), phosphatidylserine (PS) and phosphatidylglycerol (PG) mixtures. These exhibit a single composition of the polar head, i.e., PC, PS or PG, but contain several molecular species consisting of acyl chains of varying length and unsaturation, which were determined by Gas Chromatography (GC). The lipid mixtures were produced both in their hydrogenous (H) and deuterated (D) versions and were used to form lipid bilayers both on solid substrates and as vesicles in solution. The supported lipid bilayers were characterised by quartz crystal microbalance with dissipation monitoring (QCM-D) and neutron reflectometry (NR), whereas the vesicles by small angle X-ray (SAXS) and neutron scattering (SANS). Our results show that despite differences in the acyl chain composition, the hydrogenous and deuterated extracts produced bilayers with very comparable structures, which makes them valuable to design experiments involving selective deuteration with techniques such as NMR, neutron scattering or infrared spectroscopy.

Green, Rapid, Robust Determination of Aspartame in Beverages by High-Performance Liquid Chromatography-Evaporative Light Scattering Detection (HPLC-ELSD): Method Development and Validation

In recent years, eco-friendly approaches and reduction in the use of hazardous solvents have become important in applications of routine high-performance liquid chromatography (HPLC). Despite its various health side effects, aspartame (ASP) is a widely used artificial sweetener due to its high sweetness and low cost. In this study, a green, eco-friendly, cost effective, rapid, robust, and simple high-performance liquid chromatography-evaporative light scattering detection (HPLC-ELSD) method has been developed and validated for the determination of ASP in beverages. Separation was conducted isocratically on a C18 (4.6 × 150 mm, 3.5 µm) column; the mobile phase consisted of 80:20 water:ethanol at a flow rate of 1 mL min−1. The drift tube of evaporative light scattering detection (ELSD) temperature was adjusted to 50 °C and the nitrogen pressure was adjusted to 350 kPa. The HPLC-ELSD method provided a limit of detection and a limit of quantification of 0.33–0.99 µg mL−1, with recoveries of 99.4 ± 0.68% and 102.8 ± 0.17%, respectively. The precision of the method as the relative standard deviation was less than 1%. The method permitted the determination of ASP within 8 min using only 6.4 mL water and 1.6 mL ethanol. This study shows that the developed HPLC-ELSD method is suitable for determination of ASP in the food industry.

Antineoplastic and Antitrypanosomal Properties of Propolis from Tetragonula biroi Friese.

Propolis, popularly known as bee glue, is a resinous, sticky substance produced by different bee species across the globe. Studies on the biological properties of propolis from the Philippines are rare. Hence, the current study aims at the chemical characterization of propolis produced by the stingless bees Tetragonula biroi Friese from the Philippines and to investigate its antitrypanosomal and anticancer properties. The determination of the chemical composition and characterization of propolis samples was achieved using liquid chromatography-mass spectrometry (LC-MS), -high-performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD), and nuclear magnetic resonance (NMR) spectroscopy. Three major triterpenes were isolated and identified using HRESI-MS and 1H/13C NMR techniques. The spectral studies confirmed the presence of compounds such as isomangiferolic acid, 27-hydoxymangiferonic acid, and 27-hydroxyisomangiferolic acid. All crude propolis samples, isolated fractions, and pure compounds demonstrated moderate antitrypanosomal and anticancer properties compared to control drugs. Amongst the tested compounds, 27-hydoxymangiferonic acid exhibited the highest antitrypanosomal activity at a concentration of 11.6 µg/mL. The highest anticancer effect was demonstrated by the Ph-2 fraction, followed by 27-hydroxyisomangiferolic acid, with IC50 values of 129.6 and 153.3 µg/mL. Thus, it can be concluded that the observed biological activity of Philippine propolis is due to the combinatorial effect or synergistic action of the active compounds 27-hydoxymangiferonic acid and 27-hydroxyisomangiferolic acid.

Fabrication, characterization, and purification of nutraceutical diacylglycerol components from Camellia oil.

Converting triacylgycerols (TAGs) from edible oils and fats into structured diacylglycerols (DAGs) is meaningful for reducing obesity. Camellia oil, rich in linoleic acid, has the potential to form structured linoleic acid-1,3-diacylglycerol (LA-1,3-DAG) nutrients in the industry. In this research, the physicochemical properties of modified Camellia oil (MCO) by enzymatic esterification were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS), Differential Scanning Calorimetry (DSC), High Performance Liquid Chromatography-Evaporative Light Scattering Detection (HPLC-ELSD), and Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS). The relationship between reaction conditions and the DAG compositions is disclosed using multiple factors. It is found that high constituents of DAG increase the melting and crystallization temperature of MCO, lipase Novozym 435 gives the best yield of targeted nutrients (DAG, 1,3-DAG, LA-DAG), and the mixture of lipases, Lipozyme TL IM and Lipozyme RM IM, shows a synergistic effect in the synthetic process of DAG. Subsequently, MCO containing 65.4% DAG, 54.7% LA-DAG, and 47.6% 1,3-DAG content at optimal conditions (2% enzyme dosage, 4 h reaction time, 2.4:1 substrate molar ratio, 25.8% t-butanol as solvent, 60°C temperature) has been obtained and purified using silica column to obtain the final DAG oil containing 96.1% DAG, 64.7% 1,3-DAG, and 78.4% LA-DAG. High constituents of structured DAG oil rich in LA-1,3-DAG can be obtained by enzymatic esterification for industrial production.

Effects of different processing methods on the content of astragaloside in danggui buxue decoction detection by high performance liquid chromatography-evaporative light scattering detection

Danggui Buxue decoction were prepared by different processing methods of angelica sinensis and astragalus membranaceus in wine and in oil respectively. High performance liquid chromatography-evaporative light scattering detection (HPLC-ELSD) method was established for the determination of astragaloside in Danggui Buxue decoction prepared by two processing methods, and the method was verified. The regression equations of astragaloside prepared by wine was y = 1412179x − 165809, R2 = 0.99827, in the range of 0.216~0.864 mg/mL; while in oil the regression equations was y = 1283633x − 141049, R2 = 0.9947, in the range of 0.162~0.648 mg/mL. It indicated that the peak area and concentration of astragaloside showed a good linear relationship, which met the requirements of detection. The average recovery of astragaloside prepared by wine was 94.5% and RSD was 0.763%, while they were 93.6% and 2.57% astragaloside prepared by oil. It shows that the accuracy of the method is good. RSD of 12 samples from the two individuals ranged from 1.67% to 1.38% in astragaloside prepared by wine, while it ranged from 3.34% to 3.33% in astragaloside prepared by oil, which proved good intermediate precision using HPLC-ELSD method. The RSD of peak area of astragaloside of the two products were all <2% within 12 h, indicating that the two samples were stable within 12 h. The content of astragaloside prepared by wine was 0.02514±0.00026 mg/mL. The content of astragaloside prepared by oil was 0.01949±0.00023 mg/mL. The results show that the sensitivity, precision and stability of this method are good, which are accurate and accord with the methodological verification. In addition, the processing methods of angelica sinensis and astragalus membranaceus in wine are more suitable for preparing Danggui Buxue decoction.

Qili Qiangxin, a compound herbal medicine formula, alleviates hypoxia-reoxygenation-induced apoptotic and autophagic cell death via suppression of ROS/AMPK/mTOR pathway in vitro

ObjectiveQili Qiangxin (QLQX), a compound herbal medicine formula, is used effectively to treat congestive heart failure in China. However, the molecular mechanisms of the cardioprotective effect are still unclear. This study explores the cardioprotective effect and mechanism of QLQX using the hypoxia-reoxygenation (H/R)-induced myocardial injury model. MethodsThe main chemical constituents of QLQX were analyzed using high-performance liquid chromatography-evaporative light-scattering detection. The model of H/R-induced myocardial injury in H9c2 cells was developed to simulate myocardial ischemia–reperfusion injury. Apoptosis, autophagy, and generation of reactive oxygen species (ROS) were measured to assess the protective effect of QLQX. Proteins related to autophagy, apoptosis and signalling pathways were detected using Western blotting. ResultsApoptosis, autophagy and the excessive production of ROS induced by H/R were significantly reduced after treating the H9c2 cells with QLQX. QLQX treatment at concentrations of 50 and 250 μg/mL caused significant reduction in the levels of LC3II and p62 degradation (P < 0.05), and also suppressed the AMPK/mTOR signalling pathway. Furthermore, the AMPK inhibitor Compound C (at 0.5 μmol/L), and QLQX (250 μg/mL) significantly inhibited H/R-induced autophagy and apoptosis (P < 0.01), while AICAR (an AMPK activator, at 0.5 mmol/L) increased cardiomyocyte apoptosis and autophagy and abolished the anti-apoptotic effect of QLQX. Similar phenomena were also observed on the expressions of apoptotic and autophagic proteins, demonstrating that QLQX reduced the apoptosis and autophagy in the H/R-induced injury model via inhibiting the AMPK/mTOR pathway. Moreover, ROS scavenger, N-Acetyl-L-cysteine (NAC, at 2.5 mmol/L), significantly reduced H/R-triggered cell apoptosis and autophagy (P < 0.01). Meanwhile, NAC treatment down-regulated the ratio of phosphorylation of AMPK/AMPK (P < 0.01), which showed a similar effect to QLQX. ConclusionQLQX plays a cardioprotective role by alleviating apoptotic and autophagic cell death through inhibition of the ROS/AMPK/mTOR signalling pathway.

Construction of a high affinity aptamer and an aptasensor with chitosan oligosaccharide-AuNPs@Fe2+ nanozyme for highly sensitive detection of phosphatidylserine

In this study, a post-selection strategy based on increasing key bases was proposed to improve aptamers’ binding affinity. Phosphatidylserine (PS) was targeted as a model. Key bases of the original anti-PS aptamer were identified based on the molecular docking study, taken as repeating motif, and grafted onto the aptamer, with expectation to enhance the binding ability of the aptamer. An aptamer named PS-Apt-RKB2 was generated with significantly enhanced affinity. Biolayer interferometry assay results showed that the PS-Apt-RKB2 (Kd= 220.6 nM) exhibited a 29.59 times higher affinity over the original anti-PS aptamer (Kd= 6528 nM). Then, the PS-Apt-RKB2 was combined with chitosan oligosaccharide (COS) and AuNPs@Fe2+ to construct a label-free and COS-AuNPs@Fe2+ nanozyme-based colorimetric aptasensor. Under optimum conditions, the established aptasensor showed high sensitivity and demonstrated great application potentials in practice, with a limit of detection as low as 44.46 pM, and comparison rates of 91.21–105.4% when analyzing PS in real-world bioconversion samples with concentrations verified by high-performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD). This study can be further referred for developing well-performed aptamers and aptasensors for other targets.

Isolation, characterization, and antioxidant activity of neutral carbohydrates from Astragalus arbusculinus gum

“Anzaroot” is an exudate gum obtained from Astragalus species in Iran. Plant gum exudates contain hydrophilic biopolymers, and carbohydrates are the most important ingredients in the gums. Carbohydrates possess different biological properties like enhancement of immunity and antioxidant effect. This study aimed to isolate the novel carbohydrates from Astragalus arbusculinus Bornm. & Gauba gum and investigate their monosaccharides composition and antioxidant activity. For this purpose, the crude water-soluble A. arbusculinus extract was fractionated by DEAE-52 column chromatography. The A. arbusculinus carbohydrate (AAC) fraction was analyzed by high-performance liquid chromatography- evaporative light scattering detector (HPLC-ELSD), and eight compounds, including two major, were detected in its chromatogram. Subsequently, preparative-thin layer chromatography (prep-TLC) was used to isolate and purify the two major compounds, named AAC1 and AAC2. The structural features of AAC1 and AAC2 were investigated by a combination of monosaccharide component analysis using fourier-transform infrared spectroscopy (FT-IR), gas chromatography–mass spectrometry (GC–MS), gas chromatography with a flame ionization detector (GC-FID), and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS). The results indicated that AAC1 was composed of six monosaccharide components, including glucose, rhamnose, and arabinose, with a relative molar ratio of 4:1:1 and molecular weight 971.4531 Da approved by GC–MS and MALDI-TOF analyses, respectively. Also, AAC2 was composed of six monosaccharide units, including glucose, pinitol, and arabinose, with a relative molar ratio of 4:1:1 and molecular weight of 987.4084 Da. Radical scavenging activity of the two compounds was also evaluated against DPPH.

Development of methods for determining free fatty acid contents in red colored oils.

The online version contains supplementary material available at 10.1007/s10068-021-00964-2.

Seed oil of Brucea javanica induces apoptosis through the PI3K/Akt signaling pathway in acute lymphocytic leukemia Jurkat cells.

Brucea javanica oil emulsion (BJOE) has been used to treat tumor in China for more than 40 years. However, its components and effectiveness in the treatment of acute lymphocytic leukemia (ALL) and its mechanism of anti-cancer activity remain unknown. In the current study, high-performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD) was used to analyze the components of BJOE. Then, the anti-leukemia effects of BJOE were examined both in vitro and in vivo using ALL Jurkat cells and the p388 mouse leukemia transplant model, respectively. The primary ALL leukemia cells were also used to confirm the anti-leukemia effects of BJOE. The apoptotic-related results indicated that BJOE induced apoptosis in Jurkat cells and were suggestive of intrinsic apoptotic induction. Moreover, BJOE inhibited Akt (protein kinase B) activation and upregulated its downstream targets p53 and FoxO1 (forkhead box gene, group O-1) to initiate apoptosis. The activation of GSK3β was also involved. Our findings demonstrate that BJOE has anti-leukemia effects on ALL cells and can induce apoptosis in Jurkat cells through the phosphoinositide3-kinase (PI3K) /Akt signaling pathway.

Lipase-Catalyzed Production of Sorbitol Laurate in a "2-in-1" Deep Eutectic System: Factors Affecting the Synthesis and Scalability.

Surfactants, such as glycolipids, are specialty compounds that can be encountered daily in cleaning agents, pharmaceuticals or even in food. Due to their wide range of applications and, more notably, their presence in hygiene products, the demand is continuously increasing worldwide. The established chemical synthesis of glycolipids presents several disadvantages, such as lack of specificity and selectivity. Moreover, the solubility of polyols, such as sugars or sugar alcohols, in organic solvents is rather low. The enzymatic synthesis of these compounds is, however, possible in nearly water-free media using inexpensive and renewable building blocks. Using lipases, ester formation can be achieved under mild conditions. We propose, herein, a “2-in-1” system that overcomes solubility problems, as a Deep Eutectic System (DES) made of sorbitol and choline chloride replaces either a purely organic or aqueous medium. For the first time, 16 commercially available lipase formulations were compared, and the factors affecting the conversion were investigated to optimize this process, owing to a newly developed High-Performance Liquid Chromatography-Evaporative Light Scattering Detector (HPLC-ELSD) method for quantification. Thus, using 50 g/L of lipase formulation Novozym 435® at 50 °C, the optimized synthesis of sorbitol laurate (SL) allowed to achieve 28% molar conversion of 0.5 M of vinyl laurate to its sugar alcohol monoester when the DES contained 5 wt.% water. After 48h, the de novo synthesized glycolipid was separated from the media by liquid–liquid extraction, purified by flash-chromatography and characterized thoroughly by one- and two-dimensional Nuclear Magnetic Resonance (NMR) experiments combined to Mass Spectrometry (MS). In completion, we provide initial proof of scalability for this process. Using a 2.5 L stirred tank reactor (STR) allowed a batch production reaching 25 g/L in a highly viscous two-phase system.

Phospholipid analysis in whey protein products using hydrophilic interaction high-performance liquid chromatography-evaporative light-scattering detection in an industry setting

The main objective of this work was to develop an analytical method that can be used in a dairy manufacturing facility for the quantitation of phospholipids in dairy products. Total lipids from a dairy matrix were obtained first by Folch extraction. The total lipid extract was then applied to a silica gel-based solid-phase extraction column, and triglycerides and other nonpolar lipids were separated from the phospholipids and sphingolipids. Quantitation was performed by hydrophilic interaction HPLC coupled to evaporative light-scattering detection using a quaternary separation method. The method was validated using a commercial whey protein phospholipid concentrate and was used to analyze phospholipid and sphingolipid composition in buttermilk, whey protein concentrate, whey protein phospholipid concentrate, and several other dairy ingredients. This method was sensitive and reproducible and can be used in the dairy industry as a research tool to develop new value-added dairy phospholipid products, then later as a standard protocol for quality assurance analysis of current and future products.

Evaluation of a Nonionic Surfactant Foam for CO2 Mobility Control in a Heterogeneous Carbonate Reservoir

Summary In this paper, we describe a laboratory investigation of a nonionic surfactant for carbon dioxide-(CO2-) foam mobility control in the East Seminole field, a heterogeneous carbonate reservoir in the Permian Basin of west Texas. A method of high-performance liquid chromatography-evaporativelight-scattering detector (HPLC-ELSD) was followed for characterizing the surfactant stability. The foam transport process was studied in the absence and the presence of East Seminole crude oil, with test results showing that strong CO2-foam forms in either a bulk-foam test or foam-flow test. An oxygen scavenger, carbohydrazide, was found effective for controlling the stability of the surfactant up to 80°C and total dissolved solid of ∼34,000 ppm. Moreover, a phosphonate scale inhibitor was investigated and found to be compatible with the oxygen scavenger to accommodate a surfactant solution in a gypsum-oversaturated reservoir brine. During the oil-fractional flow test, an emulsion appears to form, causing a noticeable pressure increase; however, emulsion generation failed to cause a significant phase plugging in the test. Also, a STARS™ (Computer Modelling Group Ltd., Calgary, Alberta, Canada) foam model was applied to obtain the foam parameters from the foam-flow experiments at steady-state conditions. The insights from laboratory experiments better enable translation of the foam technology to the field.

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.

Detecting kinsenoside from Anoectochilus roxburghii by HPLC-ELSD with dual columns of NH2 and AQ-C18.

Kinsenoside is a characteristic component of Anoectochilus roxburghii and accounts for this herb's medicinal and edible values. No international certified standard method is available for kinsenoside analysis as well as extraction and preservation. To develop a more accurate analytical method of kinsenoside. The effects of extraction and drying methods of A. roxburghii on kinsenoside efficiency were investigated for the first time, as well as to examine the kinsenoside stability. The amino (NH2 ) and AQ-C18 columns for detecting kinsenoside extract was systematically compared by high-performance liquid chromatography evaporative light-scattering detector (HPLC-ELSD) and HPLC-diode-array detector (DAD), respectively. Kinsenoside, its epimer goodyeroside A and the degradation product during preservation were identified through HPLC-electrospray ionization mass spectrometry (ESI-MS). An accurate method of kinsenoside detection by HPLC-ELSD with dual columns of NH2 and AQ-C18 was established. The ratio of Cgoodyeroside A to Ckinsenoside (Y) was determined using the AQ-C18 column method. The concentration detected by the NH2 column was multiplied by 1/(1 + Y) as the corrected result. Using this novel method, the average deviations were reduced by 7.64%. Moreover, the efficiency of kinsenoside extraction with water was almost twice that of extraction with ethanol. Freeze drying also led to a higher extraction efficiency (38.47% increase) than hot-air drying did. Furthermore, the degradation of kinsenoside extract exceeded 70% when stored at 37 °C for 3 months. This study provides a reliable experimental method and theoretical basis for the quality control of kinsenoside from A. roxburghii, as well as other glycosides.

Determination of the marker compound, chikusetsusaponin IVa in Dolichos lablab L. using HPLC–PDA and HPLC–ELSD

Dolichos lablab L. (Leguminosae) has been used as food or health supplementary food for a long time. The aim of this study is to establish the method of quantitative analysis of chikusetsusaponin IVa for quality assessment of D. lablab using high-performance liquid chromatography (HPLC) with photodiode array (PDA) detector and evaporative light scattering detector (ELSD). Chikusetsusaponin IVa was isolated from water soluble fraction of D. lablab extract. The column for quantitative determination of chikusetsusaponin IVa was SunFire™ C18 column (4.6 × 250 mm, 5 μm) with maintained at 40 °C. Mobile phase was composed 0.1% (v/v) trifluoroacetic acid in water and acetonitrile. The drift tube temperature and nitrogen pressure in ELSD were 60 °C and 360 KPa. The injection volume and flow-rate were 10.0 μL and 1.0 mL/min. The coefficient of determination of calibration curve were 0.9997 (PDA) and 0.9995 (ELSD) and showed good linearity. The recovery of chikusetsusaponin IVa was 100.02–102.02% with relative standard deviation (RSD) value <2.00%. The RSD values of intraday and interday precisions were ≤2.79%. The content of the chikusetsusaponin IVa was detected 0.216 ± 0.004 mg/freeze-dried extract g (PDA) and 0.203 ± 0.004 mg/ freeze-dried extract g (ELSD). The established HPLC assay could be used as a basis for quality assessment of products containing D. lablab and/or D. lablab.

Analysis of astragalosides I, II and IV in some Egyptian Astragalus species and Astragalus dietary supplements using high-performance liquid chromatography/evaporative light scattering detector and non-parametric regression.

GenuTs Astragalus L. is characterised by the presence of cycloartane saponins which have wide biological activities such as antioxidant, immunomodulating' hepatoprotective and anti-inflammatory activities. From these cycloartane saponins are astragalosides I, II and IV which have been regarded as the most important active constituents in Astragalus species. This work describes the quantitative analysis of astragalosides I, II and IV in some Egyptian Astragalus species and Astragalus dietary supplements in a single run by high-performance liquid chromatography/evaporative light scattering detector (HPLC/ELSD) using gradient elution. The method of quantitation adopted in this study is the standard addition method. First and second derivative treatment of the data was performed, and the study presents comparison between two statistical regression methods for handling data; parametric and non-parametric regression methods. Derivative treatment of the chromatographic response data gives improved quantitation of the chromatographic signals. Non-parametric regression of the data using Theil's method is advantageous over the usual least squares method as it assumes that errors could occur in both x- and y-directions and they might not be normally distributed. In addition, it could effectively circumvent any outlier data points. Due to the simplicity and the good accuracy and reproducibility of the suggested methods, they could be used for analysis and quality control of Astragalus species and Astragalus dietary supplements.

Analysis of Free Oligosaccharides (fOS) from Wild-Type Saccharomyces cerevisiae (Baker's Yeast) using Two Different Extraction Methods

The glycomic profiles of free oligosaccharides (fOS) derived from misfolded N- and O-linked glycoproteins and lipid-linked oligosaccharides are important molecular signatures in various biological processes and serve as a readout of functional properties such as glycosidase inhibition. Several glycan extraction methods are available based on different sorbent chemistries that may influence the analytical profiles obtained. However, there is limited availability of studies comparing the effects of sorbent chemistries on glycan profiles. Therefore, in our study, the fOS profiles from wild-type Saccharomyces cerevisiae (Baker’s yeast) extracted using two common methods namely mixed-bed ion-exchange (MBIE) [AG50W-X12 (H+) and AG2-X8 (Cl-)] and reversed-phase (C18) sorbents were compared using total carbohydrate (phenol sulfuric acid) and total protein (bicinchoninic acid, BCA) assays, thin-layer chromatography (TLC) and high-performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD) analyses. MBIE extraction contained higher oligosaccharide and protein (0.26 mg/mL and 1.8 mg/mL) content than C18 extraction (0.11 mg/mL and 0.2 mg/mL). TLC analysis (butanol: ethanol: water = 6:3:1 and 5:4:1) showed the presence of fOS in both the MBIE and C18 extracts based on the detection of orcinol active (UV-inactive) spots. Similar peaks were present in the HPLC-ELSD chromatograms for both extractions methods with MBIE showing higher abundance. Glycan unit (GU) analysis of the dextran standard using HPLC-ELSD showed that the largest possible oligosaccharide structures detected were only di/trisaccharides. Based on all these results, MBIE extraction is a more suitable carbohydrate extraction technique compared to C18 extraction for subsequent profiling and functional studies of fOS.