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The fruit softening seriously affected the quality of Annona squamosa, and the edible coating combined with exogenous calcium had a positive effect on inhibiting the softening of A. squamosa. In this paper, the rheological properties of C-AeP-P solution and the effect of Ca2+ on the rheological properties of the solution were studied. Based on this, the indicators of fruit hardness, freshness and plumpness were used to monitor the softening effect of A. squamosa. The results show that: C-AeP-P solution showed non-Newtonian shear-thinning behavior over the range of 0.2-1.0%. With the increase of C-AeP-P concentration, the apparent viscosity and solids like properties increased. After the addition of Ca2+, C-AeP-P had apparent differences on apparent viscosity. The G′ and G″ of C-AeP-P were increased with increasing oscillation frequency. C-AeP-P and C-AeP-P+Ca2+ treatment can slow down rapidly decline of fruit hardness, increase of soluble solid content, loss of water, change peel color and regulate the expression of key enzyme genes AI and Ni. It was concluded that the coating treatment of C-AeP-P alleviates the adverse effects of quality changes during storage, so as to improve the quality and prolong the shelf life of A. squamosa.

Pleurotus ostreatus is one of the most common edible and medicinal fungi in life, and its polysaccharide has been a hot research topic in recent years. In this paper, a new intracellular polysaccharide component named P. ostreatus polysaccharide (POP-W) was obtained from the mycelium of P. ostreatus, and its structure was analyzed. The results showed that its molecular weight was Mw = 3.034 × 10

A new neutral polysaccharide, named AGP, was extracted from glycyrrhiza residue by 5% NaOH alkaline solution and purified by DEAE-cellulose and Sephadex G-150. A single and symmetrical peak was shown by HPLC, indicating that AGP is a homogeneous polysaccharide with a molecular weight of 2.89 × 103 KDa. The specific rotation of AGP was detected by a polarimeter and it was +45°. Monosaccharide composition analysis indicated that AGP was consisted of l -rhamnose: l -arabinose: d -xylose: d -mannose: d -glucose and d -galactose with a molar ratio of 1:2.33:2.85:0.69:3.05:1.54. The structure of AGP was analyzed by GC–MS, periodate oxidation, Smith degradation, FT-IR, methylation and NMR, which indicated that the AGP was composed of → 6)-β- d -Glcp-( → backbone and the →4)-α- d -Xylp-(1→, →5)-α- l -Araf-(1→, →3)-α- l -Rhap-(1→, →6)-α- d -Galp-(1→, →3,6)-α-Manp-(1→ and →1)-β- d -Glcp as branches. The results of Congo red experiment and circular dichroism (CD) showed that there was triple helix conformation in AGP. The micro-structure of AGP were detected by scanning electron microscopy (SEM), which concluded that the shape of AGP was a “thin slice” and its structure is not regular. The crystal configuration was identified by X-ray diffraction (XRD), showing that there is no crystal structure. Furthermore, the AGP exhibited certain inhibition activity on α-glucosidase.

As the main component of truffles, polysaccharides have a variety of biological activities such as anti-oxidation, anti-tumor, and hypoglycemic activity, and these activities are closely related to its structure. In this study, Tuber Aestivum crude polysaccharide (TACP) and Tuber Melanosporum crude polysaccharide (TMCP) were obtained from Tuber Aestivum and Tuber Melanosporum by using microwave-assisted hot water, and then the Sephadex G-200 column was utilized to further separate and purify Tuber Aestivum polysaccharide (TAP) and Tuber Melanosporum polysaccharide (TMP) from TACP and TMCP. The structural characterization results showed that the molecular weight of TAP was 2.18 × 10

Chitosan oligosaccharides (COS), as an important biological functional component, are mainly produced from marine resources, while their source face great challenges, such as seasonal variation, discontinuity and demineralization. In this study, the chitosan was extracted by alkaline method from Trichoderma asperellum, and then it was degraded with enzymatic hydrolysis to obtain the COS. The physicochemical characterization of chitosan from Trichoderma asperellum was compared with commercial chitosan, including chitosan content, deacetylation degree, chemical group, and molecular weight. Then, the enzymatic hydrolysis rates of Trichoderma asperellum chitosan and commercial chitosan were similar, 89.37 and 91.56%, respectively. Moreover, the composition of COS was tested by TLC, HPLC and MALDI-TOF, which results shown that Trichoderma asperellum COS was composed of chitotriose, chitopentaose and chitohexaose, and commercial COS was composed of chitotriose, chitotetraose, chitopentaose, chitohexaose and four acetylated chitohexaose. The antibacterial activity for Trichoderma asperellum COS was greatly stronger commercial COS. In conclusion, Trichoderma asperellum proved to be a novel potential source for COS production.

The crude polysaccharide LDP was extracted from mycelia of Lactarius deliciosus Gray and then purified by DEAE-52 cellulose and Sephadex G-200 to obtain a novel polysaccharide named LDP-CP. LDP-CP was mainly composed of mannose, glucose and galactose with an average molecular weight of 2.33 × 10

In this study, we investigated the protective efficacy of extracellular polysaccharide from Cordyceps militaris (CEP-I) in liver and kidney and their regulating effect on gut microbiota against Pb-induced toxicity in vivo. The results indicated that CEP-I could reduce the Pb2+ content and organ index of liver and kidney in mice. Besides, biochemical analysis showed that CEP-I could improve the activity of glutathione peroxidase (GSH-Px), malondialdehyde (MDA) and superoxide dismutase (SOD) in serum and organs, restore the physiological indexes of total protein (TP), albumin (ALB), blood urea nitrogen (BUN) and creatinine (CRE) in serum and decrease the enzyme activity of lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) in the liver and kidney of mice poisoned by Pb2+. This indicated that CEP-I has a protective effect on organs against damage in mice. In addition, CEP-I could regulate the expression of key proteins in the Nrf2 signaling pathway, including NF-E2-related factor 2 (Nrf2), Kelch-like ECH-associated protein-1 (Keap1), Heme oxygenase (HO-1) and NAD(P)H: quinone oxidoreductase 1 (NQO1). Furthermore, the intestinal flora analysis results indicated that CEP-I also has the capacity to regulate the intestinal flora imbalance caused by Pb2+ in poisoned mice. In conclusion, we hope that this study can provide theoretical basis for the treatment of tissue damage induced by Pb2+.

In this study, the purified polysaccharide (DCP-I) was extracted from Cordyceps militaris domesticated with Pb

Trichoderma asperellum ZZY had good tolerance to Pb

β-Lg is a major whey protein in cow's milk. This study was aimed to find a new kind of organic selenium compound synthesized with β-Lg and selenium dioxide as raw materials under the conditions of vacuum and low temperature. Fourier transformed infrared spectroscopy revealed that seleno-β-lactoglobulin (Se-β-Lg) displayed a strong band at 878cm(-1), belonging to SeO. Circular dichroism spectra results indicated that the conformation of Se-β-Lg was transformed and α-helical, and unordered structures were increased by 9% and 11.2%, respectively, while β-sheet and β-turn were reduced by 14.2% and 6%, respectively. Electrophoresis and matrix-assisted laser desorption/ionization time of flight mass spectrometry results showed that there were two protein bands (1-Seβ-Lg and 2-Seβ-Lg) in Se-β-Lg, only one β-Lg connected with selenate in 1-Seβ-Lg, but two β-Lgs, connected to each other, and with selenate, in 2-Seβ-Lg. Morphological observation and hematoxylin and eosin staining indicated that Se-β-lg could induce K562 cell apoptosis. These results indicated that Se-β-Lg could be synthesized by selenium conjugating β-Lg and it had antitumor activity.

The mechanisms of Pd(TFA)2-catalyzed cascade reactions of dienallenes and alkyne have been investigated by density functional theory (DFT) calculations. The computational results indicate that spiro[4.4]nonene rather than spiro[3.4]octene is the product in DCE solvent, due to the lower free-energy barrier for CO insertion from vinylpalladium intermediate than the competing olefin insertion, which is consistent with the experimental fact. The origin of regioselectivity in this reaction could be attributed to the electronic effect through performing the NPA charge calculation. In contrast, the participant solvent coordination could decrease the olefin insertion transition state effectively, and lead to the formation of product spiro[3.4]octene in CH3CN solvent.

The total synthesis of 3′-deoxy Lewis x pentasaccharide is reported. 4- O -Acetyl-2,6-di- O -benzoyl-3-deoxy-β- d -xylo-hexopyranosyl trichloroacetimidate was condensed with a diol of glucosamine to give a disaccharide, which was further fucosylated to a Lewis x trisaccharide analogue. Glycosylation of a lactoside diol with this trisaccharide provided a pentasaccharide, which after deprotection, afforded the target pentasaccharide.

SQL injection attack is one of the most serious security vulnerabilities in Web application system, most of these vulnerabilities are caused by lack of input validation and SQL parameters use. Typical SQL injection attack and prevention technologies are introduced in the paper. The detecting methods not only validate user input, but also use type-safe SQL parameters. SQL injection defense model is established according to the detection processes, which is effective against SQL injection vulnerabilities.

Glycosphingolipids are components of essentially all mammalian cell membranes and are involved in a variety of significant cellular functions, including proliferation, adhesion, motility and differentiation. Sialosyllactosylceramide (GM3) is known to inhibit the activation of epidermal growth factor receptor (EGFR). In the present study, an efficient method for the total chemical synthesis of monochloro- and dichloro-derivatives of the sialosyl residue of GM3 was developed. The structures of the synthesized compounds were fully characterized by high-resolution mass spectrometry and nuclear magnetic resonance. In analyses of EGFR autophosphorylation and cell proliferation ([3H]-thymidine incorporation) in human epidermoid carcinoma A431 cells, two chloro-derivatives exhibited stronger inhibitory effects than GM3 on EGFR activity. Monochloro-GM3, but not GM3 or dichloro-GM3, showed a significant inhibitory effect on ΔEGFR, a splicing variant of EGFR that lacks exons 2–7 and is often found in human glioblastomas. The chemical synthesis of other GM3 derivatives using approaches similar to those described in the present study, has the potential to create more potent EGFR inhibitors to block cell growth or motility of a variety of types of cancer that express either wild-type EGFR or ΔEGFR.

The regio- and stereoselective synthesis of peracetylated carbohydrate esters of stearic acid of type (VI)/(VII) or (IX)/(X) using p-toluenesulfonic acid as catalyst is described.

Mimicking Nature by using synthetic molecules that resemble natural products may open avenues to key knowledge that is difficult to access by using substances from natural sources. In this context, a novel N-acetylchitooligosaccharide analogue, beta-1,3-N-acetamido-gluco-pentasaccharide, has been designed and synthesized by using aminoglucose as the starting material. A phthalic group has been employed as the protecting group of the amine moiety, whereas a thioalkyl was used as the leaving group on the reducing end. The conformational properties of this new molecule have been explored and compared to those of the its chito analogue, with the beta-1,3 linkages, by a combined NMR spectroscopic/molecular modeling approach. Furthermore, the study of its molecular recognition properties towards two proteins, a lectin (wheat germ agglutinin) and one enzyme (a chitinase) have also been performed by using NMR spectroscopy and docking protocols. There are subtle differences in the conformational behavior of the mimetic versus the natural chitooligosaccharide, whereas this mimetic is still recognized by these two proteins and can act as a moderate inhibitor of chitin hydrolysis.

The protective effect of selenoarginine against oxidation resistance was investigated in D-galactose (D-gal)-induced aging mice. The mice were divided into four groups (n=15): a normal group, a model group, a lowdose selenoarginine group (8.35 microg of Se/kg b.w./d), and a high dose selenoarginine group (16.78 microg of Se/kg b.w./d). The aging model was induced by s.c. injection D-galactose dissolved in 0.9% normal saline of a dose of 150 mg/kg/d for 6 weeks. The mice in the normal group received s.c. injection of sterile normal saline at the same dose and frequency. The results showed that oxidative stress in the liver, kidney, and brain tissues and the serum of the mice was induced by D-galactose, but selenoarginine had an obviously protective effect against D-galactose-induced aging mice. Lowdose selenoarginine performed better than high dose selenoarginine. The protective effect of selenoarginine on D-galactose-induced aging mice can be attributed to elevation of the activity of antioxidase and enhanced antioxidant defenses.

Dendritic cell-specific intercellular-adhesion-molecule-grabbing non-integrin (DC-SIGN) is a potential target receptor for vaccination purposes. In the present study, we employed Lewis X (Le(x)) oligosaccharides, which mimic natural ligands, to target ovalbumin (OVA) to human dendritic cells (DCs) via DC-SIGN, to investigate the effect of this DC-SIGN-targeting strategy on the OVA-specific immune response. We demonstrated that Le(x) oligosaccharides could enhance the OVA-specific immune response as determined by enzyme-linked immunospot assay (ELISPOT), intracellular interferon-gamma staining and (51)Cr-release assay. An almost 300-fold lower dose of Le(x)-OVA induced balanced interferon-gamma-secreting cells compared to OVA alone. Furthermore, secretion of interleukin-10, a reported mediator of immune suppression related to DC-SIGN, was not increased by Le(x)-OVA, either alone or together with sCD40L-stimulated groups. A blocking antibody against DC-SIGN (12507) reduced the numbers of interferon-gamma-secreting cells during Le(x)-OVA stimulation, yet it did not prevent Le(x) oligosaccharides from promoting the secretion of interleukin-10 that was induced by ultra-pure lipopolysaccharide. These results suggested that the strategy of DC-SIGN targeting mediated by Le(x) oligosaccharides could promote a T-cell response. This DC-targeting may imply a novel vaccination strategy.

Carbohydate–carbohydrate recognition has recently emerged as a potentially important interaction in cell adhesion processes. One carbohydrate, the Lewis determinant (Le), is involved in murine embryogenesis, although the precise mechanism underlying this role is as yet unclear. Camediated homotypic interaction between two Le determinants has been proposed to initiate cell adhesion during the compaction stage of the embryo. Several recent studies support the existence of such calcium-mediated homotypic recognition and have also provided a body of information on the geometry, structural requirements, and energetics of a Le–Le interaction. However, in these studies the local environment of the Le was always very different from that existing at a typical cell surface. In cells, the Lebearing molecules are usually composed of a ceramide connected to the Le trisaccharide through a lactose group. This geometry considerably restricts the possible orientations of the Le [13] compared to those of soluble forms, 8] or to the large freedom in orientation provided by long flexible spacers. The ceramide in the natural Le-bearing molecules may therefore have a very strong influence on the recognition of Le borne by opposite cells, by inhibiting or enhancing the recognition. To test more directly the hypothesis that Le could serve as a promoter for cell adhesion, the challenge is to determine if the natural Le-bearing molecules allow the Le–Le recognition between two membranes. Two natural glycosphingolipids have been synthesized for this purpose. The first one, called CerLLe, is composed of a Le trisaccharide (Galb1!4[Fuca1!3]GlcNAc) attached to a ceramide (Cer) unit (two hydrophobic tails: one sphingosine and one stearic acid) through a lactose (L) group (Figure 1a). The second one, CerLLe, is used as a control and is composed of the same ceramide and lactose moieties, but has a Lewis a (Le) trisaccharide as headgroup instead of a Le determinant. Le is an isomer of Le, and the only difference between the two determinants is the position of the