Quantitative estimation of enzymatic released specific oligosaccharides from Hericium erinaceus polysaccharides using CE-LIF

Polysaccharides exhibit multiple pharmacological activities which are closely related to their structural features.Therefore,quantitatively quality control of polysaccharides based on their chemical charac-teristics is important for their application in biomedical and functional food sciences.However,poly-saccharides are mixed macromolecular compounds that are difficult to isolate and lack standards,making them challenging to quantify directly.In this study,we proposed an improved saccharide mapping method based on the release of specific oligosaccharides for the assessment of Hericium eri-naceus polysaccharides from laboratory cultured and different regions of China.Briefly,a polysaccharide from H.erinaceus was digested by b-(1-3)-glucanase,and the released specific oligosaccharides were labeled with 8-aminopyrene-1,3,6-trisulfonic-acid(APTS)and separated by using micellar electrokinetic chromatography(MEKC)coupled with laser induced fluorescence(LIF),and quantitatively estimated.MEKC presented higher resolution compared to polysaccharide analysis using carbohydrate gel elec-trophoresis(PACE),and provided great peak capacity between oligosaccharides with polymerization degree of 2(DP2)and polymerization degree of 6(DP6)in a dextran ladder separation.The results of high performance size exclusion chromatography coupled with multi-angle laser light scattering and refractive index detector(HPSEC-MALLS-RI)showed that 12 h was sufficient for complete digestion of polysaccharides from H.erinaceus.Laminaritriose(DP3)was used as an internal standard for quantifi-cation of all the oligosaccharides.The calibration curve for DP3 showed a good linear regression(R2>0.9988).The limit of detection(LOD)and limit of quantification(LOQ)values were 0.05 mg/mL and 0.2 mg/mL,respectively.The recovery for DP3 was 87.32(±0.03)%in the three independent injections.To sum up,this proposed method is helpful for improving the quality control of polysaccharides from H.erinaceus as well as other materials.

Fast saccharide mapping method for quality consistency evaluation of commercial xylooligosaccharides collected in China

Due to the extensive use of xylooligosaccharides(XOS)as functional food ingredients,many inferior goods and even adulterants are generally found in the market,which may pose a health hazard to certain populations.Chromatography method such as high-performance liquid chromatography(HPLC)and high-performance thin-layer chromatography(HPTLC)is traditionally applied for the quality analysis of XOS.However,it is time consuming due to the prolonged separation and pre-or post-derivatization procedure.In this study,a fast saccharide mapping method based on matrix-assisted laser desorption/time-of-flight mass spectrometry(MALDI-TOF-MS)was developed for the quality consistency analysis of 22 batches of XOS collected from different manufacturers in China.The time needed for saccharides analysis using MALDI-MS was less than 30 min for one plate,at least 6 times faster than that by the traditional HPTLC chromatography method.In addition,MALDI-MS possessed higher resolution for XOS with DP4-DP7 based on the difference of m/z,which is hardly separated using HPTLC.The results showed that XOS were present only in samples XY01-XY11,samples XY12-XY14 only consisted of hex oligosaccharides,and samples XY15-XY22 were free of oligosaccharides.These indicate that the quality consistency of XOS products in the China market was poor,which should be carefully investigated.

In-situ monitoring of saccharides removal of alcohol precipitation using near-infrared spectroscopy

As unsafe components in herbal medicine(HM),saccharides can affect not only the drug appearance and stabilization,but also the drug efficacy and safety.The present study focuses on the in-line monitoring of batch alcohol precipitation processes for saccharide removal using nearinfrared(NIR)spectroscopy.NIR spectra in the 4000–10,000-cm^(-1)wavelength range are acquired in situ using a transflectance probe.These directly acquired spectra allow characterization of the dynamic variation tendency of saccharides during alcohol precipitation.Calibration models based on partial least squares(PLS)regression have been developed for the three saccharide impurities,namely glucose,fructose,and sucrose.Model errors are estimated as the root-meansquare errors of cross-validation(RMSECVs)of internal validation and root-mean-square errors of prediction(RMSEPs)of external validation.The RMSECV values of glucose,fructose,and sucrose were 1.150,1.535,and 3.067 mg·mL^(-1),and the RMSEP values were 0.711,1.547,and 3.740 mg·mL^(-1),respectively.The correlation coeffcients(r)between the NIR predictive and the reference measurement values were all above 0.94.Furthermore,NIR predictions based on the constructed models improved our understanding of sugar removal and helped develop a control strategy for alcohol precipitation.The results demonstrate that,as an alternative process analytical technology(PAT)tool for monitoring batch alcohol precipitation processes,NIR spectroscopy is advantageous for both efficient determination of quality characteristics(fast,in situ,and requiring no toxic reagents)and process stability,and evaluating the repeatability.

A saccharides sensor developed by symmetrical optical waveguide-based surface plasmon resonance

We proposed a new saccharides sensor developed by symmetrical optical waveguide(SOW)-based surface plasmon resonance(SPR).This unique MgF_(2)/Au/MgF_(2)/Analyte film structure results in longer suface plasmon wave(SPW)propagation lengths and depths,leading to an increment of resolution.In this paper,we managed to decorate the dielectric interface(MgF_(2) layer)by depositing a thin polydopamine film as surface adherent that provides a platform for secondary reactions with the probe molecule.3-Aminophenylboronic acid(3-PBA)is chosen to be the saccharides sense probe molecule in the present work.The aqueous huumnor of Diabetes and Cataract patient whose blood glucose level is normal are analyzed and the results dermonstrated that this sensor shows great potential in monitoring the blood siugar and can be adapted in the field of biological monitoring in the future.

Stereochemical Effects in Mass Spectrometry ( Ⅶ )——Negative Ion Fast Atom Bombardment Mass Spectro-metry of Saccharides with Areneboronic Acids as Reagents

1-Naphthylboronic acid and 2, 4-dimethylphenylboronic acid can react stereospecif-ically with hydroxy groups of saccharides on the probe tip of a fast atom bombardment mass spectrometer to form characteristic negatively-charged boronate ions. On the basis of the relative abundances of these characteristic ions, the epimers of mono- and di-saccharides may be distinguished. This approach was proved to be a simple and effective means for identifying sugars. The collisional activation moss spectra of these characteristic ions are also discussed.

A Comparison of Microwave-Assisted Heating with Conventional Heating of Sweet Potato <i>(Ipomoea batatas)</i>: Analysis of Monosaccharides and Disaccharides

Microwave-assisted heating has been recently used for extracting nutrient components from food materials. The technique sometimes invokes reactions from nutrient compounds during microwave-irradiation because it activates water molecules to reach a high temperature. The microwave-irradiation produced 5.3 g maltose per 100 g sweat potatoes in 30 s, which was faster than conventional heating (3.9 g maltose per 100 g in 300 s). Fructose level increased with the longer reaction time under microwave-irradiation (from 1.33 g to 1.65 g in 120s), but decreased with a longer reaction time under conventional heating (from 0.99 g to 0.83 g in 1200 s). This study demonstrates the differences in the reactions and products between microwave-irradiation and conventional heating.

Utilization of hydralazine as a reactive matrix for enhanced detection and on-MALDI-target derivatization of saccharides

Saccharides are a sort of ubiquitous and vital molecules within the whole life.However,the application of saccharides analysis with matrix-assisted laser desorption/ionization mass spectrometry(MALDI-MS)is restricted by their low ionization efficiency and the instability of the sialic acid fraction.Derivatization strategy based on nonreductive amination provides a good solution,however,this is often time consuming and may result in sample loss due to removal of excessive derivatization reagents.Herein,hydralazine(HZN)was utilized as a reactive matrix for labeling reducing saccharides directly on MALDI target which eliminated tedious sample preparation and avoided sample loss.After optimization,effective and reproducible on-MALDI-target derivatization of neutral and acidic saccharides was achieved in both positive and negative modes.Compared with 2,5-dihydroxybenzoic acid(DHB)and 9-aminoacridine(9-AA),HZN improved the detection sensitivity of reducing saccharides and provided more abundant fragment ions in MS/MS analysis.Moreover,26 kinds of neutral glycans and 5 kinds of sialic glycans were identified from ovalbumin(OVA)and bovine fetuin,respectively.Combined with the statistical models,this strategy could be used to distinguish and predict samples of 6 brands of beer,and discriminate 2 kinds of beer fermentation modes.In addition,HZN was applied for quantitative analysis of glucose in urine samples,and the obtained urine glucose concentrations of diabetic patients were consistent with the clinical test results,showing the potential of qualitative and quantitative analysis of reducing saccharides in complex samples.

Nenofiltration for separation and purification of saccharides from biomass

Saccharide production is critical to the development of biotechnology in the field of food and biofuel.The extraction of saccharide from biomass-based hydrolysate mixtures has become a trend due to low cost and abundant biomass reserves.Compared to conventional methods of fractionation and recovery of saccharides,nanofiltration(NF)has received considerable attention in recent decades because of its high selectivity and low energy consumption and environmental impact.In this review the advantages and challenges of NF based technology in the separation of saccharides are critically evaluated.Hybrid membrane processes,i.e.,combining NF with ultrafiltration,can complement each other to provide an efficient approach for removal of unwanted solutes to obtain higher purity saccharides.However,use of NF membrane separation technology is limited due to irreversible membrane fouling that results in high capital and operating costs.Future development of NF membrane technology should therefore focus on improving material stability,antifouling ability and saccharide targeting selectivity,as well as on engineering aspects such as process optimisation and membrane module design.

A Long-Wavelength Fluorescent Probe for Saccharides Based on Boronic-Acid Receptor

A single boronic acid-based fluorescent probe （compound CSP） for saccharides was designed and synthesized. The probe, with an a,fl-unsaturated ketone conjugated into the coumarin fluorophore, was synthesized by 4 steps from the commercial material 4-diethylamino salicylaldehyde. The electron push-pull effect is enhanced with the N,N-diethyl amino as the electron donor and the carbonyl as the electron acceptor. Both the absorption （463 nm） and emission （616 nm） maxima of CSP are in the visible wavelength region with a Stokes shift of about 150 nm, which ensures CSP a potential probe for biological application. Under near physiological conditions, significant fluores- cence enhancement of CSP was observed upon the addition of some saccharides, namely, D-sorbitol, D-fructose, D-glucose, D-mannose and D-galactose. The probe showed relatively high sensitivity towards D-fructose and D-sorbitol, and their detection limits were 0.05 mmol/L and 0.1 mmol/L, respectively.

Selective separation of protein and saccharides by ionic liquids aqueous two-phase systems

In the present work,it was found that aqueous solution of a hydrophilic ionic liquid (IL),1-butyl-3-methylimidazolium dicyanamide ([C4mim][N(CN)2]),could be separated into an aqueous two-phase system (ATPS) by inorganic salts such as K2HPO4 and K3PO4.The top phase is IL-rich,while the bottom phase is phosphate-rich.It was shown that 82.7%-100% bovine serum albumin (BSA) could be enriched into the top phase and almost quantitative saccharides (arabinose,glucose,sucrose,raffinose or dextran) were preferentially extracted into the bottom phase in a single-step extraction by [C4mim][N(CN)2] + K2HPO4 ATPS.The extraction efficiency of BSA from the aqueous saccharide solutions was influenced by the molecular structure of saccharides.The conductivity,dynamic light scattering (DLS) and transmission electron microscopy (TEM) were combined to investigate the microstructure of the IL-rich top phase and the possible mechanism for the selective separation.It is suggested that the formation of the IL aggregate and the IL aggregate-BSA complex plays a significant role in the separation of BSA from aqueous saccharide solutions.This is the first example for the selective separation by ILs-based ATPSs.It is expected that these findings would have potential applications in bio-analysis,separation,and IL recycle.

Chemical Fingerprint for Identification and Quality Control of Saccharides in Danhong Injection Based on HPLC-ELSD with Chemometrics

Chemical fingerprinting has been widely used for the quality control of complex natural products including traditional Chinese medicines and botanical drugs. However, there is still lack of appropriate method to monitor the batch-to-batch consistency of hydrophilic constituents, such as saccharides and oligosaccharides. In the present study, we developed a novel approach based on high performance liquid chromatography with evaporative light scattering detector(HPLC-ELSD) for establishing saccharide fingerprinting of Danhong Injection(DHI), which is a widely used botanical drug for treating cardiovascular diseases. Major saccharides in DHI were isolated and four compounds including fructose, glucose and two oligosaccharides were identified. The structures of two novel saccharides named glycerol-1-O-galactfpyranosyl-(1→4)-O-arabmofuranoside, and glycerol-1-O-galactpyranosyl-(1→4)[O-arabmfuranosyl-(1→3)]-O-arabinofuranoside were confirmed by NMR, HR-ESI-MS and GC-MS for the first time. The establishment approach was successfully applied to distinguishing 12 batches of DHI from other botanical drugs with the aid of principle component analysis as well as to evaluating batch-to-batch consistency with the help of calculating similarity of tmgerprints. Our findings indicate that the chemical fingerprint of saccharides can be a useful tool for the quality control of complex natural products.

Stereochemical effects in mass spectrometry——Ⅺ.Negative ion fast atom bombardment mass spectrometry of saccharides and glycosides using phenylboronic acid as reagent

The negative ion fast atom bombardment (NIFAB) mass spectra of mono-,di-saccharides and glycosides using phenylboronic acid (PBA) as reagent have been studied.In the ion source,PBA reacts stereospecifically with the molecules containing cis-vicinal glycols to form characteristic ions, from which the stereo-isomers of saccharides can be definitely distinguished.Disaccharides and glyco- sides with β-glycosidic linkage seem to be unfavorabale to react with PBA,therefore,by comparison of the abundances of the characteristic ions,the configuration of the glycosidic linkage in these compounds may be inferred.

Rapid differentiation of simple saccharides based on cluster ions by paper spray tandem mass spectrometry

Simple saccharides have a variety of biological functions,but their structural diversity and inherent structural features pose a major challenge for rapid analysis.In this work,we developed a derivative-free and ion mobility-free method for the rapid analysis of monosaccharides and disaccharides using paper spray tandem mass spectrometry.Trimeric cluster ions consisting of saccharide analytes,ligands and transition metal ions are used as precursor ions.We defined the R-value as the ratio of the intensity of the product ion that loses one molecule of ligand over the intensity of the product ion that loses one molecule of saccharide via collision induced dissociation(CID).The species and conformation of simple saccharides can be easily differentiated by calculating this R-value.With the capability of directly analyzing clinical samples using paper spray ionization,our method can be used to rapidly quantify the molar ratio of galactose to glucose in dried plasma samples to aid in the diagnosis of galactosemia.The analytical strategy provided herein has good potential to be applied to a wide range of saccharide analysis applications in the future.

The effects of maltodextrin/starch in soy protein isolate–wheat gluten on the thermal stability of high-moisture extrudates

This study aimed to investigate the interaction between maltodextrin/starch of different molecular weight distributions and soy protein isolate (SPI)–wheat gluten (WG) matrix during high-moisture extrusion.Two maltodextrins (dextrose equivalent (DE):10 and 20) and wheat starch were extruded with SPI–WG blend in a system of 65,70,and 75%moisture to investigate their effects on texture and thermal stability.Incorporating 5%maltodextrin (DE10) in the SPI–WG matrix improved the fiber structure and thermal stability.When wheat starch was thoroughly gelatinized during subsequent sterilization,the fiber structure and thermal stability were also improved.It was found that the plasticization caused by small-molecular weight saccharides and enhanced phase separation caused by large-molecular weight saccharides changed the melting temperature of blends and significantly improved the texture and thermal stability of extrudates.

Impact of hydrothermal process on the nutrient ingredients of restaurant garbage

In order to recover the nutrient resource from restaurant garbage, a complete trial with 2 factors on 5 levels of experiments was carried out. The temperature and heating time are the main factors influencing on hydrothermal process （HP） by which improves the degradability and digestibility of the restaurant garbage favorably to make animal feeds or fertilizer. The results showed the variation of protein, saccharide, and oil in the garbage. It showed that protein dissolved and liquefied during hydrothermal process, which made organic nitrogen in solid phase transfer to liquid phase. After heating at 180℃ for 60min, organic nitrogen in liquid phase began to transform into ammonia. It also showed that hydrothermal process could promote the dextrinization, dissolution of the starch and its hydrolysis to reducing sugar, due to that starch in the restaurant garbage decreases and reducing sugar increases. When the temperature reached 140℃, the reducing sugar started to decrease due to chemical reactions. The cellulose was stable at 100-180℃. The floatable oil increased markedly in the hydrothermal process. The suitable condition for de-oil was observed at 160℃ heating for 80 min. Furthermore, the extraction of grease from the solid phase accords with first-order reaction dynamic model.

Detection of Lectins by Saccharide-gold Nanoparticle Conjugates

A general functionalization strategy was reported,which enables one to conjugate saccharide（SA） on gold nanoparticle（GNP） surface without affecting SA properties.First,disulfide phenylboronic acid（Bor） functionalized GNPs（Bor@GNPs） were synthesized by the reaction of citrate stabilized GNPs of 13 nm in diameter with the mixture of Bor and pentapeptide（Cys-Ala-Leu-Asn-Asn,CALNN）.Subsequently,the SA-GNP conjugates（SA@GNPs） were prepared by coupling SA to the GNP surface via the reaction of phenylboronic acid（PBA） with the cis-diol configuration in SA.The interactions of three SA@GNPs with three lectins have been analyzed by UV-visible spectroscopic and transmission electronic microscopic（TEM） techniques,respectively.The experimental results demonstrate that SA@GNPs can efficiently bind to lectins and show a great promise as optical probes for monitoring specific affinities of lectins for SA,and detecting lectins with high sensitivity.

A Novel Method for the Synthesis of Bioactive Benzimidazolyl-Phenoxyacetic Acid O-Acetylglucosyl Saccharide Esters

A novel method of synthesis of nitro or trifluoromethyl substituted benzimidazolyl phenoxyacetic acid O-acetylglucosyl saccharide esters by the reaction of O-acetylglucosyl bromide with substituted benzimidazolyl phenoxyacetic acid at room temperature was developed. 4 dimethylaminopyridine （DMAP） was used as catalyst, triethylamine （Et3N） was used as deacid reagent, three saccharide esters were synthesized in the system of DMAP/ Et3 N. The catalytic mechanism of DMAP/Et3N was discussed. The results show that DMAP is an effective catalyst, the yields can reach 50%. The test indicates that the title compounds show better antiplantviral activity.

Fuel Gas Production from Biomass Sources by Radio Frequency In-Liquid Plasma Method

Cellulose is a kind of saccharide that is the main component in cell walls of plants and therefore is the organic compound that exists in the largest amount in nature. The purpose of this experiment is to convert cellulose to a fuel. Radio frequency (RF) in-liquid plasma is generated in a cellulose distributed solution and a glucose solution, and the generation gas rate is measured. While hydrogen is the main gas generated by the plasma breakdown, carbon monoxide, carbon dioxide, and low-grade flammable gases are also produced. In the glucose water solution or the glucose distributed solution, the solution itself evaporates and decomposes inside the plasma but since the saccharides are non-volatile, they cannot penetrate into the plasma and are not decomposition. However, when the cellulose is at concentrations of 30 wt% or more, it becomes granular and can directly enter the plasma as a solid, where the plasma decomposes the cellulose itself, significantly increasing the amount of gas generated. In addition, the spectrometry of the plasma emission shows the solution after the creation of plasma has the ability to absorb ultraviolet light.

Development of porphyrin-based fluorescent sensors and sensor arrays for saccharide recognition

Saccharide sensing is a very meaningful research topic as saccharides are involved in many biological activities.However,it is challenging to design molecular sensors for saccharides because this family of compounds is hydromimetic in aqueous solutions and shares a similar chemical structure.In this review,research progress in the development of porphyrin-based saccharide sensors is described with representative examples.We focus on using porphyrin as the signal reporter because porphyrins exhibit unique advantages in high chemical stability,long emission wavelength,and multiple structural modification strategies.Reported literature results have been classified into mainly two sections according to the general working principles of the porphyrin sensor molecules.In the first section,recognition unit,design strategy and sensing performance of traditional porphyrin-based selective saccharide sensors are discussed.While in the second section,development of porphyrin-based sensor arrays for pattern recognition of saccharides has been summarized.Looking through the design strategy and sensing performance of reported achievements,it is reasonable to anticipate a bright future for designing practical porphyrin-based saccharide sensors.