Most bacterial cell surface glycans are structurally unique, and have been considered as ideal target molecules for the developments of detection and diagnosis techniques, as well as vaccines. Chemical synthesis has been a promising approach to prepare well-defined oligosaccharides, facilitating the structure-activity relationship exploration and biomedical applications of bacterial glycans. L-Galactosaminuronic acid is a rare sugar that has been only found in cell surface glycans of gram-negative bacteria. Here, an orthogonally protected L-galactosaminuronic acid building block was designed and chemically synthesized. A synthetic strategy based on glycal addition and TEMPO/BAIB-mediated C6 oxidation served well for the transformation of commercial L-galactose to the corresponding L-galactosaminuronic acid. Notably, the C6 oxidation of the allyl glycoside was more efficient than that of the selenoglycoside. In addition, a balance between the formation of allyl glycoside and the recovery of selenoglycoside was essential to improve efficiency of the NIS/TfOH-catalyzed allylation. This synthetically useful L-galactosaminuronic acid building block will provide a basis for the syntheses of complex bacterial glycans.
Carbohydrates ; Glycosides ; Oligosaccharides ; Oxidation-Reduction ; Polysaccharides/chemistry*

OBJECTIVETo study the effect of seedling quality on growth, yield and quality of Rehmannia glutinosa at harvest and build a basis for its GAP.

METHODThe seedling quality of R. glutinosa in main producing regions was surveyed to understand the current status of seedling quality. Field experiments with different varieties and seedling quality were conducted to measure dry matter accumulation with different growth of R. glutinosa and oligosaccharide content, and economic yield at harvest.

RESULTThe seedling was randomly selected by farmers in R. glutinosa producing regions. Seedling quality could significantly improve on seedling emergence rate, and promote seedling growth, especially with early stage R. glutinosa, finally increase yield at harvest. At harvest, 63% and 50% of yield with A and B seedling could be improved for variety of 85-5, and 50% and 47% of yield could be increased for variety of Beijing No. 1, compared to the C seeding.

CONCLUSIONIn cultivation, the seedlings with the diameter > 1.5 cm should be transplanted firstly.

Oligosaccharides ; analysis ; Rehmannia ; chemistry ; growth & development ; Seedlings ; chemistry ; physiology

α-amylase is an endonucleoside hydrolase that hydrolyzes the α-1, 4-glycosidic bonds inside polysaccharides, such as starch, to generate oligosaccharides, dextrins, maltotriose, maltose and a small amount of glucose. Due to the importance of α-amylase in food industry, human health monitoring and pharmaceuticals, detection of its activity is widely required in the breeding of α-amylase producing strains, in vitro diagnosis, development of diabetes drugs, and the control of food quality. In recent years, many new α-amylase detection methods have been developed with improved speed and sensitivity. This review summarized recent processes in the development and applications of new α-amylase detection methods. The major principle of these detection methods were introduced, and their advantages and disadvantages were compared to facilitate future development and applications of α-amylase detection methods.
Humans ; alpha-Amylases/chemistry* ; Polysaccharides ; Oligosaccharides ; Starch ; Maltose

Comparing to Chitosan, Chitosan-oligosaccharides have several special functions, such as water-soluble, antitumor activity, immunostimulating effects, and antimicrobial activity. The chitosan-oligosaccharide, the molecular weight of which was about 5000, was used as research model. According to the agarose gel electrophoresis and UV spectrophotometer it was proved that electrostatic interaction was playing a very important role in the formation process of chitosan-oligosaccharide/DNA complex. The potential of adsorbing DNA on chitosan-oligosaccharide was analyzed by gel electrophoresis and UV spectrophotometer, and it was indicated that chitosan-oligosaccharide can improve the storage and structure stability of DNA. To check its protection ability to DNA by DNase I digestive experiment, the result showed that chitosan-oligosaccharide could load with plasmid effectively and protect DNA from being digested by DNase I. It was proved that chitosan-oligosacchide was safe and effective for gene delivery and will have a very good future in the field of gene therapy.
Chitosan ; chemistry ; DNA ; chemistry ; Gene Transfer Techniques ; Genetic Vectors ; Nanoparticles ; chemistry ; Oligosaccharides ; chemistry

To apply chitooligosaccharide in the preparation of baicalin compound, in order to increase the drug dissolution in vitro, and investigate the basic property of the compound. Baicalin-chitooligosaccharide compound was prepared by using the solvent method. The structure and physicochemical properties of compound were analyzed by using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and infrared vibrational spectrum (IR), and its dissolution behavior was also investigated. The results showed that the compound prepared at baicalin-chitooligosaccharide molar ratio of 1 : 1 could significantly improve the dissolution of baicalin. The results of DSC and XRD analysis suggested that baicalin may exist in an amorphous state. IR results indicated the interaction between baicalin and chitooligosaccharide. The baicalin-chitooligosaccharide compound could significantly improve dissolution in vitro of drug.
Calorimetry, Differential Scanning ; Chemistry, Pharmaceutical ; Drug Carriers ; chemistry ; Drugs, Chinese Herbal ; chemistry ; Flavonoids ; chemistry ; Oligosaccharides ; chemistry ; Spectroscopy, Fourier Transform Infrared

Heparin is a very important anticoagulant drug. Currently, heparin is mainly extracted from porcine mucosa. However, animal-derived heparin shows low anticoagulant activity due to the low proportion of the anticoagulant active unit, the GlcNS6S-GlcA-GlcNS6S3S-Ido2S-GlcNS6S pentasaccharide. In this study we proposed an enzymatic strategy to sulfate the animal-sourced heparin to increase the proportion of anticoagulant pentasaccharide and the anticoagulant activity. First, three sulfotransferases HS2ST, HS6ST, and HS3ST were expressed tentatively in Escherichia coli and Pichia pastoris. After measuring the sulfotransferase activity, we confirmed P. pastoris GS115 is the better host for sulfotransferases production. Then, the maltose binding protein (MBP) and thioredoxin (TrxA) were fused separately to the N-terminal of sulfotransferases to increase enzyme solubility. As a result, the yields of HS2ST and HS6ST were increased to (839±14) U/L and (792±23) U/L, respectively. Subsequent sulfation of the animal-sourced heparin with the recombinant HS2ST, HS6ST and HS3ST increased the anticoagulant activity from (76±2) IU/mg to (189±17) IU/mg.
Animals ; Escherichia coli ; Heparin ; chemistry ; Oligosaccharides ; chemistry ; Pichia ; Sulfotransferases ; biosynthesis ; Swine

Chitosanases represent a class of glycoside hydrolases with high catalytic activity on chitosan but nearly no activity on chitin. Chitosanases can convert high molecular weight chitosan into functional chitooligosaccharides with low molecular weight. In recent years, remarkable progress has been made in the research on chitosanases. This review summarizes and discusses its biochemical properties, crystal structures, catalytic mechanisms, and protein engineering, highlighting the preparation of pure chitooligosaccharides by enzymatic hydrolysis. This review may advance the understandings on the mechanism of chitosanases and promote its industrial applications.
Chitosan/chemistry* ; Chitin ; Glycoside Hydrolases/genetics* ; Protein Engineering ; Oligosaccharides/chemistry* ; Hydrolysis

In this study, we found that when Pseudomonas mendocina NK-01 accumulated intracellular carbon reserve, medium chain length poly (3-hydroxyalkanoates), it also synthesized extracellular saccharides, alginate oligosaccharides. The high carbon nitrogen ratio of culture medium facilitated alginate oligosaccharides production. We analyzed the structure of alginate oligosaccharide by Ultraviolet-Visible Spectrophotometry, Fourier Transform Infrared Spectroscopy, 1H and 13C of Nuclear Magnetic Resonance, and found that it was compounded in line from beta-D-mannuronic acids and alpha-L-gluronic acids via beta-(1-->4)/ alpha-(1-->4) bonds, which acetylated partly on the 2- and/or 3-hydroxy. In addition, we determined the weight-average molecular weight of alginate oligosaccharides by gel permeation chromatography to be 2054.
Alginates ; chemistry ; Glucuronic Acid ; biosynthesis ; chemistry ; genetics ; Hexuronic Acids ; chemistry ; Molecular Weight ; Oligosaccharides ; biosynthesis ; chemistry ; genetics ; Pseudomonas mendocina ; metabolism

OBJECTIVETo determine determinate five oligosaccharides, namely sucrose, 1-kestose, nystose, 1F-fructofurano-syinystose, bajijiasu contained in Morinda officinalis with an HILIC-ELSDI) method.

METHODWaters XBridge Amide (4.6 mm x 150 mm, 3.5 microm) hilic column was adopted for gradient elution, with acetonitrile (A) and 0.2% triethylamine (B) as the mobile phase. The column temperature was set at 40 degrees C, with the flow rate of 0.8 mL x min. Waters 2424 evaporative light scattering detector (ESLD) was used as detector, with the gas flow of 275.79 kPa and drift tube temperature of 90 degrees C.

RESULTThe detection range for the five oligosaccharides were 2.128-21.28 microg for sucrose (r = 0.999 3), 1.864-18.64 microg for 1-kestose (r = 0.999 6), 1.92-19.2 microg for nystose (r = 0.999 8), 1.912-19. 12 microg for 1F-fructofuranosyinystose (r = 0.999 5), 2.368-23.68 microg for bajijiasu (r = 0.999 4), respectively. The recovery of the five oligosaccharides ranged between 92.81%-102.8% (n = 6).

CONCLUSIONThe method is so simple, accurate and highly reproducible that it can be used as an analytical method for effective evaluation of the quality of M. officinalis herbs.

Chromatography, Liquid ; instrumentation ; methods ; Drugs, Chinese Herbal ; analysis ; Morinda ; chemistry ; Oligosaccharides ; analysis ; Scattering, Radiation

We purified a novel mannose binding lectin form Musca domestica pupae by affinity chromatography on Con A-Sepharose 4B and DEAE weak anion-exchange chromatography. By SDS-PAGE, MBL-1 yielded a single band with the molecular weight of 24 kDa. It was a glycoprotein detected by periodic acid-schiffs staining reaction, with 97.36% protein and 2.1% oligosaccharide. Meanwhile, the results of beta-elimination reaction, infrared spectroscopy, atomic force microscopy and protein sequencing instrument show that MBL-1 was an ellipsoidal-shaped monomer with 60-100 nm in diameter. N-glycoside bond linked oligosaccharide chain and the N-terminal blocked peptide chain. Further study suggested that MBL-1 promote the proliferation of macrophage in a concentration-dependent manner. The scanning electron microscope analysis shows that MBL-1 promoted the activation of macrophages. These results show that MBL-1 purified from Musca domestica pupae possesses immune regulation effect, serving a reference basis to develop natural immune-modulator.
Animals ; Glycoproteins ; analysis ; Houseflies ; chemistry ; Immunomodulation ; immunology ; physiology ; Macrophages ; immunology ; Mannose-Binding Lectin ; chemistry ; physiology ; Oligosaccharides ; analysis ; Pupa ; chemistry