N-丙酰-唾液酸衍生物的化学酶法合成及在测定禽蛋中唾液酸含量的应用

为实现禽类蛋黄和蛋清中N-乙酰神经氨酸(N-acetylneuraminic acid,Neu5Ac)的准确定量,消除禽蛋样品中分析物以外的物质产生的基质效应对分析结果造成的影响,本研究以甘露糖胺为底物采用化学酶法合成了非天然唾液酸衍生物5-溴-4-氯-3-吲哚-β-D-半乳糖苷-N-丙酰-唾液酸(5-Bromo-4-...     

多年生藤本豆多糖对小鼠免疫功能的影响

目的:研究多年生藤本豆多糖对小鼠免疫功能的影响。方法:测定多年生藤本豆多糖对小鼠淋巴细胞增殖、巨噬细胞吞噬活力及溶血素生成的影响。结果:多年生藤本豆多糖明显增强B淋巴细胞和T淋巴细胞的增殖,促进小鼠巨噬细胞的吞噬活力和溶血素抗体生成。结论:多年生藤本豆多糖明显增强小鼠的细胞免疫和体液免疫功能。     

蚕蛹蛋白对小鼠免疫作用的研究

目的:研究蚕蛹蛋白对小鼠免疫功能的影响。方法:测定蚕蛹蛋白对小鼠淋巴细胞增殖、巨噬细胞吞噬活力及溶血素生成的影响。结果:蚕蛹蛋白明显增强B淋巴细胞和T淋巴细胞的增殖,促进小鼠巨噬细胞的吞噬活力和溶血素抗体生成。结论:蚕蛹蛋白明显增强小鼠的细胞免疫和体液免疫功能。     

多年生藤本豆蛋白对小鼠免疫功能的影响

目的:研究多年生藤本豆蛋白对小鼠免疫功能的影响。方法测定多年生藤本豆蛋白对小鼠淋巴细胞增殖、巨噬细胞吞噬活力及溶血素生成的影响。结果:多年生藤本豆蛋白明显增强B淋巴细胞和T淋巴细胞的增殖,促进小鼠巨噬细胞的吞噬活力和溶血素抗体生成。结论:多年生藤本豆蛋白明显增强小鼠的细胞免疫和体液免疫功能。     

Comparison of spectrophotometric and HPLC methods for determining sialic acid in infant formulas

Two methods for determining sialic acid in infant formulas – spectrophotometry and HPLC with fluorescence detection – have been optimised and validated, the first one allows to determine total sialic acid while the second allows to differentiate the two main forms of sialic acid (N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc)). A common sample preparation procedure (hydrolysis and purification) for both methods has been proposed. The linearity (from 6 to 150 μg of total sialic acid in the assay for spectrophotometry, and from 12.5 to 250 ng and 1 to 5 ng of Neu5Ac and Neu5Gc, respectively, for HPLC) is adequate. The detection and quantification limits (0.29 and 0.97 mg of total sialic acid/L of reconstituted sample, respectively, for spectrophotometry, and 0.03 and 0.08 mg Neu5Ac/L; 0.003 and 0.009 mg Neu5Gc/L of reconstituted sample, respectively, for HPLC) are low enough for the determination of sialic acid in infant formulas. The precision of both methods, expressed as relative standard deviation, is less than 6%, and the accuracy evaluated by recovery assays show 104% recovery for spectrophotometry; 95% for Neu5Ac and 109% for Neu5Gc for HPLC. Samples analysed show no significant differences (α < 0.05) attributable to the method used; consequently, both of them could be applied after common sample preparation, the choice of technique depending on the facilities available in the laboratory.     

红毛藻多糖对环磷酰胺诱导的免疫抑制小鼠的免疫调节机理

本研究以环磷酰胺（cyclophosphamide,CTX）诱导的免疫力低下小鼠为模型,探究红毛藻多糖（Bangia fusco-purpurea polysaccharides,BFP）对免疫抑制小鼠免疫力的影响。结果表明,BFP干预能够显著提高免疫抑制小鼠自然杀伤细胞活性、巨噬细胞吞噬能力和清除碳颗粒能力;增强T淋巴细胞增殖作用,上调CD4＋ T细胞比例,降低CD8＋ T细胞比例并增加CD4＋/CD8＋,降低辅助性T细胞17和CD3－CD19＋ B细胞的比例;提高血清溶血素、免疫球蛋白（immunoglobulin,Ig）A和IgG、免疫相关细胞因子白细胞介素（interleukin,IL）-2、IL-6、肿瘤坏死因子-α（tumor necrosis factor-α,TNF-α）、干扰素-γ（interferon-γ,INF-γ）的质量浓度,对免疫抑制小鼠的非特异性免疫、细胞免疫及体液免疫均具有良好的调节作用。在明确BFP对免疫抑制小鼠免疫功能具有保护作用的基础上,分析其对免疫抑制小鼠肠道相关免疫细胞表面受体的影响,发现BFP能够显著或极显著下调Toll样受体（Toll-like receptor,TLR）2、TLR4、IL-6和TNF-α基因（P＜0.05）和蛋白（P＜0.01）的表达,推测BFP通过TLR2/TLR4下游相关信号通路调节轴发挥增强免疫力的功能。本研究可为深入认识海洋食品的营养价值,推进海洋食品在居民膳食中的应用提供科学依据。     

Chemical characterisation of oligosaccharides in commercially pasteurised dromedary camel (Camelus dromedarius) milk

It has been suggested that bactrian camel milk and colostrum may be a good source of biologically significant oligosaccharides but, although the oligosaccharides found in bactrian camel milk and colostrum have been characterised, those in dromedary camel milk have not. In this study, seven oligosaccharides from commercially available pasteurised dromedary camel milk were characterised using ¹H nuclear magnetic resonance spectroscopy. The following oligosaccharides were detected: Gal(β1-3)Gal(β1-4)Glc (3′-galactosyllactose), Gal(β1-4)GlcNAc(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (lacto-N-neohexaose), Neu5Ac(α2-3)Gal(β1-4)Glc (3′-sialyllactose), Neu5Ac(α2-6)Gal(β1-4)Glc (6′-sialyllactose), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-4)Glc (sialyl-3′-galactosyllactose), Neu5Ac(α2-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyllacto-N-novopentaose a) and Neu5Ac(α2-6)Gal(β1-4)GlcNAc(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (monosialyllacto-N-neohexaose).     

诺丽酒增强免疫功能的实验研究

通过脾淋巴细胞转化实验、二硝基氟苯诱导的迟发性变态反应、抗体生成细胞检测、血清溶血素测定、碳廓清实验、腹腔巨噬细胞吞噬荧光微球实验、NK细胞活性以及IL-1、IL-6、IL-10、TNF-α测定,分别观察诺丽酒对小鼠细胞免疫功能、体液免疫功能和单核- 巨噬细胞功能的影响。结果表明,20 mL/kg·BW剂量诺丽酒能即可显著提高小鼠脾淋巴细胞转化、巨噬细胞廓清与吞噬活性及NK细胞活性,与酒基对照组相比,分别提高了42.14%、16.79%、66.23%、24.78%,并促进细胞因子IL-6、IL-10与TNF-α释放,表明诺丽酒具有增强机体免疫力的功效。     

鲍内脏多糖体内抗氧化及增强小鼠免疫活性

为研究鲍内脏多糖（abalone visceral polysaccharides,AVP）体内抗氧化及增强小鼠免疫活性作用,采用 乙醇氧化损伤模型动物实验设计和正常小鼠增强小鼠免疫力实验设计,通过测定实验小鼠肝脏超氧化物歧化酶 （superoxide dismutase,SOD）活力,谷胱甘肽（glutathione,GSH）、丙二醛（malondialdehyde,MDA）和蛋白 质羰基含量综合评价AVP的体内抗氧化能力;通过测定正常实验小鼠免疫器官指数、足跖增厚、溶血素抗体水平、 吞噬指数α,从免疫器官指数、细胞免疫、体液免疫以及非特异性免疫方面综合评价AVP增强小鼠免疫活性能力。 结果表明：AVP显著提高氧化损伤模型小鼠肝脏SOD活力和GSH含量（P＜0.05）,显著降低小鼠肝脏MDA含量和 蛋白质羰基含量（P＜0.05）,表现出良好的体内抗氧化能力;AVP能极显著提高正常小鼠脾脏指数和胸腺指数、 足跖增厚和血清溶血素水平（P＜0.01）,显著提升小鼠吞噬指数（P＜0.05）,在免疫器官指数、细胞免疫、体液 免疫以及非特异性免疫4 个方面均表现出较好的增强小鼠免疫活性效果;另外,数据表明AVP体内抗氧化及增强小 鼠免疫活性作用与其剂量呈正相关性。鲍内脏多糖是一种具有良好的抗氧化和增强免疫活性的物质,为鲍内脏的精 深加工与产业化开发提供了理论依据。     

Chemical characterisation of saccharides in the milk of a reindeer (Rangifer tarandus tarandus)

Although reindeer milk is utilised as a food in some areas in the world, including Mongolia, the saccharides in this milk have thus far not been explored. In this study, the structures of the separated saccharides were characterised by ¹H-nuclear magnetic resonance spectroscopy to be as follows: Gal(β1-3)Gal(β1-4)Glc (3′-galactosyllactose, 3′-GL), Gal(β1-6)Gal(β1-4)Glc (6′-galactosyllactose, 6′-GL), Gal(β1-4)Glc (lactose), Neu5Ac(α2-6)Gal(β1-4)Glc (6′-N-acetylneuraminyllactose, 6′-SL), Neu5Ac(α2-6)Gal(β1-4)GlcNAc(β1-3)Gal(β1-4)Glc (sialyllacto-N-tetraose c, LST c) and uridine 5′-diphospho-α-N-acetyl-D-glucosamine (UDP-GlcNAc). In addition, monosaccharide-α-1-phosphate and some other UDP-mono or oligosaccharides were found, but Neu5Ac(α2-3)Gal(β1-4)Glc (3′-N-acetylneuraminyllactose, 3′-SL) was not detected. Lactose was the predominant saccharide. It may be concluded that, in this milk, the concentration of phosphorylated or UDP-saccharides was higher than that of Neu5Ac containing oligosaccharides; this should be a significant feature of this species milk.     

Chemical characterization of the oligosaccharides in Bactrian camel (Camelus bactrianus) milk and colostrum

Bactrian camel milk and colostrum are commonly used as foods in Mongolia, whose people believe that these products promote human health. It has been hypothesized that milk oligosaccharides are biologically significant components of human milk, acting as receptor analogs that inhibit the attachment of pathogenic microorganisms to the colonic mucosa, and as prebiotics, which stimulate the growth of bifidobacteria within the infant colon. To evaluate their biological significance, we studied the oligosaccharides present in samples of Bactrian camel milk and colostrum. Using ¹H-nuclear magnetic resonance spectroscopy, we identified and characterized the following oligosaccharides of camel colostrum: Gal(β1–4)[Fuc(α1–3)]Glc (3-fucosyllactose), Gal(β1–3)Gal(β1–4)Glc (3′-galactosyllactose), Gal(β1–6)Gal(β1–4)Glc (6′-galactosyllactose), Neu5Ac(α2–3)Gal(β1–4)Glc (3′-sialyllactose), Neu5Ac(α2–6)Gal(β1–4)Glc (6′-sialyllactose), Neu5Ac(α2–3)Gal(β1–3)Gal(β1–4)Glc (sialyl-3′-galactosyllactose), Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)Gal(β1–4)Glc (sialyllacto-N-tetraose c), Neu5Ac(α2–3)Gal(β1–3)[Gal(β1–4)GlcNAc(β1–6)]Gal(β1–4)Glc (sialyllacto-N-novopentaose a), Gal(β1–3)[Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–6)]Gal(β1–4)Glc (sialyllacto-N-novopentaose b); and Neu5Ac(α2–6)Gal(β1–4)GlcNAc(β1–3)[Gal(β1–4)GlcNAc(β1–6)]Gal(β1–4)Glc (monosialyllacto-N-neohexaose). The oligosaccharides in the mature camel milk were characterized as 3′-galactosyllactose, Gal(β1–3)[Gal(β1–4)GlcNAc(β1–6)]Gal(β1–4)Glc (lacto-N-novopentaose I), and 3′-sialyllactose.     

甘薯叶柄藤多糖的免疫调节作用研究

研究薯蔓多糖(PSPV)对动物的非特异性免疫和特异性体液免疫调节作用。采用碳粒廓清实验研究PSPV对正常和免疫低下小鼠的非特异性免疫功能;血清溶血素测定法研究PSPV的特异性体液免疫功能。结果表明:PSPV可提高正常和免疫低下小鼠的廓清指数K和呑噬指数α,800mg／kg剂量的PSPV可显著提高小鼠血清的血清溶血素HC50。结论:PSPV具有促进单核巨噬细胞系统吞噬功能的作用,可增强小鼠的非特异性免疫功能,同时也可极显著地增强小鼠的特异性体液免疫功能。     

鲜马奶对小鼠免疫功能的影响

研究了鲜马奶对小鼠免疫功能的影响.测定了小鼠胸腺指数、脾脏指数、腹腔巨噬细胞吞噬功能、血清溶血素含量及T淋巴细胞转化率：结果表明，鲜马奶能增加胸腺指数及脾脏指数，增强巨噬细胞吞噬功能，使血清溶血素含量及T淋巴细胞转化率增高。结论：鲜马奶能使小鼠免疫器官重量增加．并能增强小鼠非特异性免疫功能、特异性体液免疫功能及特异性细胞免疫功能。     

蜂王幼虫对小鼠免疫功能的影响及机理探讨

采用耳肿胀法,半为溶血值法及小鼠腹腔巨噬细胞蚕噬鸡血红细胞试验评价蜂王幼虫对细胞免疫,体液免疫及非特异性免疫的影响。结果;ＤＴＨ显示蜂王幼虫１０ｇ／ｋｇ剂量组耳肿胀度显著高于对照组;蜂王幼虫５ｇ／ｋｇ,１０ｇ／ｋｇ剂量组的半数溶血值水平与对照组相比差异均有显著性;小鼠腹腔巨细胞蚕鸡血红细胞试验显示,蜂王幼虫各个剂量组与对照组比较差异均有显著性。     

白酒对小鼠机体免疫功能的调节作用

通过计算脾指数与胸腺指数、腹腔巨噬细胞吞噬鸡红细胞实验,三硝基氯苯（PC）诱导迟发性变态反应试验和血清溶血素测定,分别观察迎玺牌＂硬是好＂酒对小鼠免疫器官重量、腹腔巨噬细胞功能、细胞免疫功能和体液免疫功能的影响。结果表明,酒样20 mL（成品）/kg和40 mL（成品）/kg能显著升高脾指数与胸腺指数,提高巨噬细胞吞噬功能,降低小鼠耳廓肿胀度（P〈0.05）,升高血清溶血素含量（P〈0.01）。     

鼠李糖乳杆菌R9639对小鼠免疫功能的影响及机制研究

目的 研究鼠李糖乳杆菌(Lactobacillus rhamnosus)R9639对小鼠免疫功能的调控作用。方法 分别灌胃给予小鼠2.5、5.0、15.0 mg/kg的鼠李糖乳杆菌R9639 30 d后,测定小鼠脏器/体重比;抗体生成细胞实验、血清溶血素测定实验评价其对小鼠体液免疫功能的影响;脾淋巴细胞转化实验、迟发型变态反应实验评价其对小鼠细胞免疫功能的影响;小鼠碳廓清实验、小鼠腹腔巨噬细胞吞噬鸡红细胞实验评价其对小鼠单核-巨噬细胞功能的影响;NK细胞活性测定实验评价其对小鼠NK细胞活性的影响。结果 鼠李糖乳杆菌R9639对小鼠胸腺/体重比值、脾脏/体重比值均无显著影响;与对照组相比,5.0、15.0 mg/kg的鼠李糖乳杆菌R9639组HC₅₀明显升高(P<0.05)、迟发型变态反应显著增强(P<0.05)、小鼠的碳廓清能力显著提高(P<0.05);15.0 mg/kg的鼠李糖乳杆菌R9639组小鼠NK细胞活性显著增强(P<0.05)。结论 鼠李糖乳杆菌R9639可通过增强体液免疫、细胞免疫、单核-巨噬细胞功能及NK细胞活性来增强小鼠的免疫功能。     

Determining Neu5Ac in infant formula with ultra‐performance liquid chromatography–tandem mass spectrometry

The aim of this work was to measure N‐acetylneuraminic acid (Neu5Ac) in milk‐based infant formulas. The analysis was performed by ultra‐performance liquid chromatography–tandem mass spectrometry (UPLC‐MS/MS). The total Neu5Ac were released using trichloroacetic acid and hydrochloric acid and purified using a HLB column. The linearity from 0.05 to 5.0 μg/mg Neu5Ac was adequate. Sialic acid recoveries ranged from 91.8% to 112.4%. The detection and quantification limits (limit of detection, 0.01 μg Neu5Ac/mg; limit of quantitation, 1.08 μg Neu5Ac/mg) were low enough to determine the sialic acid in infant formulas. The validated method is highly reproducible and sensitive, and it is easy to perform.     

小分子阿胶肽的免疫调节作用

目的:研究小分子阿胶肽(LMWPC)对小鼠免疫功能的调节作用。方法:采用凯氏定氮及高效凝胶色谱法分析LMWPC的蛋白质含量及分子量分布情况,利用小鼠血清溶血素滴度测定和小鼠脾细胞抗体生成实验,观察0.18、0.35和1.05 g/kg·bw剂量的LMWPC对小鼠体液免疫的影响,采用小鼠迟发型变态反应实验和ConA诱导小鼠脾淋巴细胞转化实验,考察LMWPC对小鼠细胞免疫的影响。结果:LMWPC的分子量主要集中在1000 Da以下,蛋白质含量丰富,高达(88.84±1.77) g/100 g。与对照组相比,高剂量组小鼠的半数溶血值(HC₅₀)为(76.8±4.2)(P<0.05),足趾肿胀为(0.35±0.03) mm (P<0.05),小鼠脾淋巴细胞转化实验OD值为(0.344±0.052)(P<0.05)。与低、中剂量相比,高剂量组具有最佳的增加小鼠血清溶血素水平、增强小鼠迟发型变态反应和促进小鼠脾淋巴细胞转化增殖的能力;而中剂量组LMWPC能明显增加小鼠脾细胞抗体生成的效果。结论:本研究条件下,LMWPC能够提高小鼠的体液免疫及细胞免疫功能,对小鼠的免疫功能有正向调节作用。     

亚麻籽油对小鼠免疫功能的影响

分别以0.15、0.05、0.025 g/mL的亚麻籽油作为高、中、低剂量组,按10 mL/（kg·d）给予小鼠30 d灌胃试验,分析测定小鼠体重、脏体比（胸腺指数、脾指数）、细胞免疫功能（小鼠淋巴细胞转化试验,迟发型变态反应试验）、体液免疫功能（抗体生成细胞试验,血清溶血素测定试验）、单核-巨噬细胞功能（碳廓清试验,腹腔巨噬细胞吞噬鸡红细胞试验）和NK细胞活性,以考察亚麻籽油对小鼠免疫功能的影响。结果表明：亚麻籽油对小鼠的体重、脏体比、血清溶血素以及单核-巨噬细胞功能无显著影响（P＞0.05）;与对照组比较,中剂量组和高剂量组能够显著提高小鼠的细胞免疫功能（淋巴细胞转化,迟发型变态反应）和NK细胞活性（P＜0.05）。研究结果说明亚麻籽油对小鼠具有增强免疫力的功能。     

Large-scale preparation and glycan characterization of sialylglycopeptide from bovine milk glycomacropeptide and its bifidogenic properties

Bovine glycomacropeptide (GMP) is a 7,000-Da glycopolypeptide released from κ-casein during cheese making. The O-glycan chains linked to GMP have many biological activities, but their utilization for nutraceutical products is limited due to their low content. To concentrate the functional glycan chains of GMP, we prepared sialylglycopeptide concentrate (SGC) from GMP-containing whey protein concentrate via proteolytic digestion of peptide chains and concentration of sialylglycopeptide by ultrafiltration using membranes with a molecular weight cut-off of 1,000 Da. The abundant saccharides detected in the prepared SGC were N-acetylneuraminic acid (Neu5Ac: 32.3% wt/wt), N-acetylgalactosamine (11.3%), and galactose (10.2%), which constitute O-glycans attached to GMP. The Neu5Ac content in SGC was found concentrated at approximately 4.8-fold of its content in GMP-containing whey protein concentrate (6.8%). Structural analysis of O-glycopeptides by liquid chromatography tandem mass spectrometry identified 88 O-glycopeptides. Moreover, O-acetylated or O-diacetylated Neu5Ac was detected in addition to the previously characterized O-glycans of GMP. Quantitative analysis of O-glycan in SGC by fluorescence labeling of chemically released O-glycan revealed that a disialylated tetrasaccharide was the most abundant glycan (76.6% of the total O-glycan). We further examined bifidogenic properties of SGC in vitro, which revealed that SGC served as a more potent carbon source than GMP and contributes to the growth-promoting effects on certain species of bifidobacteria. Overall, our study findings indicate that SGC contains abundant O-glycans and has a bifidogenic activity. Moreover, the protocol for the preparation of SGC described herein is relatively simple, providing a high yield of glycan, and can be used for large-scale preparation.