Initial host-pathogen interactions explained by the Organism Prearranged Recognition Theory: fundamental role of saccharides

Herein based on literature available a hypothesis is provided about molecular basis for initial events in establishment interactions.This hypothesis asserts that:"recognition and interaction that occur between organisms is prearranged.There are membrane receptors with or without soluble components derived from the respective organisms that bridge specific interactions".Organisms'prearranged recognition theory(OPRT)can be specifically applied to host-microbe interactions where most microbes are coated(opsonised)by soluble components(opsonins)from the host,but there are also some microbes that can bypass host opsonization expressing receptors for the host cells or secreting host’s opsonin-like molecules.The receptors involved in organism's interactions,their specificity and repertoire depend on saccharides from glycoproteins,glycolipids,and polysaccharides(glycans)which are abundant extracellular components.Based in OPRT is possible to explain species-specific interactions and several other phenomena,such as hyper-infectivity,tissue tropism,differential sensitivity to disease depending on type O-blood,and tumoral cell promiscuity.The lipid raft domain in cellular membrane is proposed as the main location where interactions will trigger cellular responses.Possible scientific and biotechnology applications and alternative routes to modify organism's interactions and consequences are discussed.It is a novel hypothesis regarding the degree to which an organism's interactions are prearranged and the role of saccharides epitopes.

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.

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.

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 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.

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.

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.

广西不同油茶物种花蕊花蜜糖含量分析

油茶(Camellia)为异花虫媒授粉树种,自花授粉基本不育,结果依赖传粉者。为探讨油茶花蕊花蜜中的糖含量与蜜蜂访花的关系,以陆川油茶(C.vietnamensis)、广宁红花油茶(C.semiserrata)、普通油茶(C.oleifera)和香花油茶(C.osmantha)盛开期的花朵为研究对象,采用离子色谱法分析不同油茶物种花蕊花蜜中的糖类(半乳糖、葡萄糖、蔗糖、麦芽糖、果糖和阿拉伯糖)含量。结果表明,离子色谱法可有效、准确地对油茶花蕊花蜜中的糖含量进行分析;不同油茶物种花蕊花蜜中的糖含量存在明显差异,但均以果糖、蔗糖、葡萄糖、半乳糖和麦芽糖为主,均未检出阿拉伯糖;果糖在各油茶物种花蕊花蜜中的含量均最高。香花油茶花蕊花蜜中的果糖、蔗糖、葡萄糖、半乳糖和麦芽糖含量均明显高于其他3个油茶物种,分别为19.62、8.39、14.79、0.25和0.18 mg/g。香花油茶花蕊花蜜中的果糖、蔗糖和葡萄糖含量高是其吸引中华蜜蜂(Apis cerana)访花的因素之一。

不同采后处理对恭城月柿褐变、活性氧代谢及糖类的影响

本文分析了有氧、真空和真空+1-MCP三种采后处理方式对脱涩后柿子贮藏过程中果实褐变、活性氧代谢和糖类的影响,并对褐变与各指标的相关性进行分析。真空和真空+1-MCP组柿子贮藏过程中的褐变指数BI低于有氧组,其中真空+1-MCP组褐变程度最低;三种采后处理柿子贮藏过程中SOD、APX活性分别呈下降和上升的趋势,真空组柿子SOD活性最低,真空和真空+1-MCP条件下柿子APX活性高于有氧组;真空和真空+1-MCP抑制柿子CAT活性的增加,减少H2O2积累,同时抑制羟自由基的能力和抗坏血酸含量较低。真空和真空+1-MCP组柿子还原糖含量低于有氧组,其中真空+1-MCP组增加最慢,从贮藏开始时的14.10%增加至12 d时的14.87%;真空+1-MCP组柿子果胶含量下降缓慢。相关性分析可知,不同采后处理柿子贮藏过程中柿子褐变与各指标的相关性并不相同,但柿子褐变指数BI均与果胶呈负相关,与还原糖呈正相关。综合可知真空和真空+1-MCP条件更有利于抑制脱涩后月柿的褐变。

裂解性多糖单加氧酶驱动不同结构甲壳素降解的研究

为实现裂解性多糖单加氧酶(Lyticpolysaccharidemonooxygenase,LPMO)高效驱动甲壳素的降解,本文分析了来源于Oceanobacillussp.J11TS1的LPMO(OsLPMO10A)与甲壳素酶协同作用于不同晶型和不同致密性甲壳素的活性差异。研究表明,OsLPMO10A对β-甲壳素的结合活性和裂解作用比对α-甲壳素更强。采用一锅法反应,OsLPMO10A与甲壳素酶协同作用于β-甲壳素的协同度(2.41)和甲壳二糖产量((2.46±0.17)mg/mL)均高于协同作用于α-甲壳素的协同度(1.94)和甲壳二糖产量((0.68±0.04)mg/mL)。此外,虽然OsLPMO10A对致密性降低的α-甲壳素仍具有结合和氧化活性,但OsLPMO10A与甲壳素酶的协同度随着α-甲壳素致密性的降低而趋向于1。上述结果表明,甲壳素结构对LPMO驱动的甲壳素生物转化有重要影响。

野菊花水提物对RAW264.7炎症细胞模型的抗炎作用及其机制

目的建立以脂多糖(LPS)诱导的RAW 264.7巨噬细胞为模型,探讨野菊花提取液(CID)通过核转录因子(NF-κB)信号通路发挥抗炎活性的作用及其分子机制。方法以噻唑蓝(MTT)法检测不同浓度CID对RAW 264.7巨噬细胞活性的影响以筛选适宜的实验浓度;分别采用Griess法和酶联免疫吸附试验(ELISA)测定50、100、200μg·mL^(-1) CID干预后各组细胞中一氧化氮(NO)和肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)的释放量;实时荧光定量聚合酶链式反应(RT-PCR)分析各组中环氧合酶-2(COX-2)和诱导型一氧化氮合酶(iNOS)mRNA的相对表达水平;免疫印迹实验(WB)观察各组中nuclear factor-kappa B p65(NF-κB p65)、inhibitor kappa B(IκB-α)和磷酸化IκB-α(p-IκB-α)的蛋白表达。结果50~200μg·mL^(-1)的CID可显著降低LPS诱导RAW264.7巨噬细胞中NO、TNF-α和IL-6的生成量(P<0.01),并能下调COX-2和iNOX mRNA的相对表达(P<0.01)、下调p-IκB-α、总的NF-κB p65、细胞核NF-κB p65的蛋白相对含量(P<0.01),并上调IκB-α、细胞质NF-κB p65的相对含量(P<0.01)。结论CID可有效降低LPS诱导RAW 264.7巨噬细胞的炎症因子释放,其机制可能与通过减少TNF-α等关键蛋白表达以及通过抑制NF-κB等炎症信号通路激活来抑制炎症发生有关。

多羟基糖类结合剂对Al_(2)O_(3)-SiC-C质无水炮泥性能的影响

为减少炮泥的污染,开发环境友好型炮泥,采用棕刚玉、SiC、焦炭、绢云母、蓝晶石、黏土、Si_(3)N_(4)-Fe粉等为主要原料,NS-FH为复合烧结助剂,分别以环保无污染的多羟基糖类葡萄糖和蔗糖为结合剂,制备Al_(2)O_(3)-SiC-C质无水炮泥。研究了葡萄糖或蔗糖溶液的外加量(加入质量分数分别为0、8%、9%、10%、11%、12%、13%)对该炮泥性能的影响。结果表明:以多羟基糖类葡萄糖或蔗糖为结合剂,可制得综合性能较好的Al_(2)O_(3)-SiC-C质无水炮泥;外加12%(w)的蔗糖溶液时,无水炮泥的性能最佳,其马夏值为1.14 MPa,1350℃埋石墨烧后的线收缩率、体积密度和显气孔率分别为0.72%、2.41 g·cm^(-3)和24.4%,常温耐压强度和高温抗折强度(1400℃埋碳并保温30 min)分别为40.1和12.1 MPa。

三种薯蓣属顶生翅组植物地下块茎糖含量研究

研究粘山药、毡毛薯蓣、光亮薯蓣地下部分糖类的含量,为深入研究和开发奠定基础。参照GB5009.7—2016(第一法)、GB5009.9—2016(第一法)、SN/T 4260—2015标准,适当修改制样方法,进行还原糖、淀粉、粗多糖含量的检测。粗多糖还原能力用还原碱性酒石酸铜相当葡萄糖含量进行检测和表达。实验结果表明:粘山药、毡毛薯蓣、光亮薯蓣,可溶于80%vol浓度乙醇的总还原糖含量分别为2.28%、6.31%、5.16%,淀粉含量分别为11.61%、12.55%、1.43%,粗多糖含量分别为20.38%、54.62%、39.27%。粘山药、毡毛薯蓣、光亮薯蓣中100 g粗多糖的还原能力相当于葡萄糖的质量分别为13.12、2.12、8.36 g。毡毛薯蓣地下块茎还原糖、淀粉、粗多糖含量非常显著地高于粘山药、光亮薯蓣;粘山药粗多糖的还原能力非常显著地大于毡毛薯蓣、光亮薯蓣;毡毛薯蓣、粘山药有潜在的开发应用前景。

酱油酿造中糖类的研究进展

传统酿造酱油是亚洲菜系中用来提高鲜味的调味品。以大豆、麸皮等含淀粉的原料经微生物发酵制得的酱油中含有氨基酸、糖类、有机酸等多种成分,其中以葡萄糖为主的许多单糖、寡糖、多糖等对酿造酱油的风味和品质起到重要作用。文章从酱油酿造中糖类的种类与含量、形成机制、影响因素、功能作用等方面进行了综述。

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.

基于PMP柱前衍生HPLC法测定汽爆加工对蕨菜糖类成分影响研究

多糖占蕨菜干重的8%左右,是其主要活性成分之一,为探究汽爆加工对蕨菜糖类成分的影响,本研究以4个产地蕨菜干制样品为原料,经相同汽爆工艺处理,测定总多糖得率,采用1-苯基-3-甲基-5-吡唑啉酮(PMP)柱前衍生高效液相色谱(HPLC)法,建立指纹图谱,结合对照品确证共有峰,并对游离单糖含量及多糖的单糖组成进行检测,同时借助化学计量学方法分析样品间的差异性和相似性。结果表明,与干制样品相比,汽爆样品总多糖得率为(12.02±1.89)%,增加了55%(P<0.01)。8批蕨菜指纹图谱共标识12个共有峰,通过对照品确证其中5个共有峰,分别为鼠李糖、甘露糖、葡萄糖、半乳糖和阿拉伯糖,系统聚类分析(HCA)和主成分分析(PCA)结果可将8批样品归为2类。游离单糖含量和多糖单糖组成测定结果显示,相比于干制样品,汽爆样品中游离半乳糖、甘露糖、鼠李糖含量分别减少6.02、0.42、0.34 mg/g,葡萄糖和阿拉伯糖的含量分别增加0.14、0.09 mg/g;多糖单糖组成中葡萄糖、鼠李糖的比例显著(P<0.01)增加,平均增加量为1.64%和0.94%。本研究发现汽爆工艺处理显著增加了蕨菜样品中糖类成分的提取得率,并影响其含量及结构,这为后续的活性研究提供依据,为蕨菜汽爆加工的质量控制提供参考。

硅烷衍生化GC-MS检测香精中糖类物质成分

建立了基于硅烷衍生化气相色谱-质谱联用法快速检测香精中17种糖类物质的方法。结果表明:衍生化的最佳条件为以BSTFA为衍生化试剂、衍生化温度40℃、衍生化时间40 min,在此条件下共鉴定出17种糖类物质。17种糖类物质在一定质量浓度内具有良好的线性关系(R^(2)>0.99)。方法的检出限为0.027~0.077μg/mL,加标回收率为94.80%~110.03%,相对标准偏差为3.03%~8.06%。实际样品测定结果表明,建立的方法能够快速准确地检测香精中17种糖类物质成分,满足对香精中糖类物质的同时检测。