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1.
酵母细胞壁多糖的主要活性成分是β-葡聚糖和甘露聚糖,在动物机体内与肠道受体竞争吸附病原菌以及在肠道降解提供能量,改善动物肠道环境;也会利用其结构与Fe2+离子螯合抑制羟自由基的产生以及防止脂质过氧化连锁反应等,提高抗氧化能力;其特有的化学位点会通过多种分子间作用力吸附霉菌毒素;β-葡聚糖和甘露聚糖通过作用于巨噬细胞调节多种细胞因子,通过多个途径增强机体的特异性和非特异性免疫力。目前在养殖业中酵母细胞壁多糖可用于替代金霉素、硫酸黏杆菌素等抗生素控制鸡的坏死性肠炎、减少水产动物细菌感染、降低猪、牛等幼畜腹泻率、预防各种老化性疾病以及促进动物生长发育。对酵母细胞壁多糖现有的提取方法进行比较,提取酵母细胞壁β-葡聚糖,选用超声辅助酶解产率最高、效果最好;用低浓度的氢氧化钠（NaOH）溶液提取甘露聚糖以及酶碱法提取酵母细胞壁多糖效果最好。分离纯化技术包括有脱蛋白、脱色、单一多糖的分离,将其分离纯化效果分别比较,除去酵母细胞壁多糖中蛋白质的最佳方法是Sevage法;脱除色素的最佳方法是颗粒活性炭吸附法;单一多糖分离纯化采用DEAE-纤维素A52阴离子交换柱和Sephadex G-100柱联用的方法最佳。酵母细胞壁多糖结构鉴定一般采用高效液相色谱法（HPLC）测定多糖的单糖组成,高效凝胶渗透色谱测定多糖的均匀性和分子质量,傅立叶变换红外光谱（FT-IR）、气相色谱-质谱（GC-MS）和核磁共振（NMR）测定多糖的精细结构。文章通过对酵母细胞壁多糖的作用及应用、提取、分离纯化和鉴定技术进行阐述,为酵母细胞壁多糖作为抗生素替代品在畜牧业生产中的推广应用提供理论依据,为抗生素替代品的研发提供新的思路。 相似文献
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为探讨黄芪多糖、酵母胞壁多糖和虫草菌丝体多糖对动物免疫功能的影响,本试验分为对照组和黄芪多糖、酵母胞壁多糖、虫草菌丝体多糖,3种多糖等量复配4个试验组。每组选用昆明种小鼠40只,对照组小鼠每只灌胃1mL生理盐水,黄芪多糖、酵母胞壁多糖、虫草菌丝体多糖和3种多糖等量复配组小鼠每只灌胃量为140mg多糖/kg体重,每隔10d取样1次,分别检测增重率、免疫器官指数、血细胞数和外周血IgG含量。结果表明,黄芪多糖组、酵母胞壁多糖组和虫草菌丝体多糖组均可显著提高小鼠增重率、免疫器官指数、血细胞数目及外周血IgG含量(P<0.05),复合多糖组则与单多糖组相比差异显著(P<0.05)。说明3种多糖组及其混合多糖组均能提高小鼠免疫力,且最好的为混合多糖组。 相似文献
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Swamy HV Smith TK MacDonald EJ Boermans HJ Squires EJ 《Journal of animal science》2002,80(12):3257-3267
The co-occurrence of Fusarium mycotoxins in contaminated swine diets has been shown to result in synergistic toxicity beyond that observed for individual toxins. An experiment was conducted, therefore, to investigate the effects of feeding a blend of grains naturally contaminated with Fusarium mycotoxins on growth, brain regional neurochemistry, serum immunoglobulin (Ig) concentrations, serum chemistry, hematology, and organ weights of starter pigs. Three levels of glucomannan polymer (GM polymer, extract of yeast cell wall, Alltech Inc.) were also tested for its efficacy to overcome Fusarium mycotoxicoses. A total of 175 starter pigs (initial weight of 10 +/- 1.1 kg) were fed five diets (seven pens of five pigs per diet) for 21 d. Diets included (1) control, (2) blend of contaminated grains, (3) contaminated grains + 0.05% GM polymer (4) contaminated grains + 0.10% GM polymer and (5) contaminated grains + 0.20% GM polymer. Diets containing contaminated grains averaged 5.5 ppm deoxynivalenol, 0.5 ppm 15-acetyldeoxynivalenol, 26.8 ppm fuuric acid, and 0.4 ppm zearalenone. Feed intake and weight gain of all pigs fed contaminated grains was significantly reduced compared to controls throughout the experiment. The weights of liver and kidney, expressed as a percentage of body weight, were lower in pigs fed the contaminated diet than in those fed the control diet. The feeding of contaminated grains significantly reduced concentrations of dopamine in the hypothalamus and pons and concentrations of dihydroxyphenylacetic acid and norepinephrine in the pons. The ratios of 5-hydroxyindoleacetic acid to serotonin, however, were elevated in the hypothalamus and pons. The feeding of contaminated grains increased serum IgM and IgA concentrations, while serum IgG concentrations were not altered. The supplementation of GM polymer prevented some of the mycotoxin-induced alterations in brain neurotransmitter and serum Ig concentrations. In summary, the feeding of grains naturally contaminated with Fusarium mycotoxins reduced growth, altered brain neurochemistry, increased serum Ig concentrations, and decreased organ weights in starter pigs. Some of the Fusarium mycotoxin-induced changes in neurochemistry and serum Ig concentrations can be prevented by the feeding of yeast cell wall polymer at appropriate concentrations, although this was not reflected in increased growth rate under these experimental conditions. 相似文献
4.
本研究旨在探讨饲粮中添加酵母壁多糖对断奶仔猪肠道挥发性脂肪酸和微生物菌群的影响。试验采用单因素试验设计方法,选取180头遗传背景一致、健康状况良好、胎次和体重接近的21日龄断奶仔猪,随机分为4个组,每组5个重复,每个重复9头猪。4个组试验猪分别饲喂对照饲粮(未添加酵母壁多糖)、0.15%酵母壁多糖饲粮、0.30%酵母壁多糖饲粮和0.45%酵母壁多糖饲粮。试验期21 d。结果表明:1)与对照组相比,饲粮中添加0.15%、0.30%和0.45%酵母壁多糖显著提高了仔猪结肠乙酸的含量(P0.05);其中,0.30%和0.45%酵母壁多糖还显著提高了结肠丙酸、丁酸以及总挥发性脂肪酸的含量(P0.05),且二者之间差异不显著(P0.05)。2)与对照组相比,饲粮中添加0.15%、0.30%和0.45%酵母壁多糖显著降低了盲肠沙门氏菌和大肠杆菌数量(P0.05),且0.30%和0.45%酵母壁多糖组之间差异不显著(P0.05)。由此可知,酵母壁多糖可提高仔猪肠道挥发性脂肪酸含量,并改善肠道微生物菌群结构,根据回归方程预测,酵母壁多糖在仔猪饲粮中的适宜添加水平为0.31%~0.40%。 相似文献
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《动物营养（英文）》2015,(4)
Fungal biochemical pathways can yield various compounds that are not considered to be necessary for their growth and are thus referred to as secondary metabolites. These compounds have been found to have wide ranging biological effects and include potent poisons(mycotoxins). Mycotoxins invariably contaminate crops and(thus) animal feeds. The intestine is the key link between ingested mycotoxins and their detrimental effects on the animal. Effects on the intestine, or intestinal environment, and immune system have been reported with various mycotoxins. These effects are almost certainly occurring across species. Most, if not all, of the reported effects of mycotoxins are negative in terms of intestinal health, for example, decreased intestinal cell viability, reductions in short chain fatty acid(SCFA)concentrations and elimination of beneficial bacteria, increased expression of genes involved in promoting inflammation and counteracting oxidative stress. This challenge to intestinal health will predispose the animal to intestinal(and systemic) infections and impair efficient digestion and absorption of nutrients, with the associated effect on animal productivity. 相似文献
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Oral administration of yeast, Saccharomyces cerevisiae, enhances the cellular innate immune response of gilthead seabream (Sparus aurata L.) 总被引：3，自引：0，他引：3
Ortuño J Cuesta A Rodríguez A Esteban MA Meseguer J 《Veterinary immunology and immunopathology》2002,85(1-2):41-50
The effects of including lyophilised whole yeast, Saccharomyces cerevisiae, in the diet on the seabream innate immune response were investigated. Gilthead seabream (Sparus aurata L.) specimens were fed four different diets for 4 weeks: a commercial diet as control and the same diet supplemented with 1, 5 or 10 g/kg yeast. After 1, 2 and 4 weeks, serum complement titres, as a humoral parameter, and phagocytic, respiratory burst, myeloperoxidase and natural cytotoxic activities of head-kidney leucocytes, as cellular parameters, were evaluated. The results showed that yeast supplements enhanced all the latter responses, but not the humoral response. This enhancement was dose-dependent except for the cytotoxic activity that was only stimulated by the lower dose of yeast assayed. As yeast cell walls are able to enhance the seabream cellular innate immune response, these results support the possible use of whole yeast as natural inmunostimulants in common fish diets. 相似文献
9.
The aim of this study was to determine the optimal method of the yeast cell wall breaking which could obtain the maximum extraction rate of yeast polysaccharide. The extraction rate of yeast polysaccharide and the cell wall broken rate were used as the evaluating indexes. The conditions of ultrasonic disruption, repeated freezing and thawing, ultrasonic cleaning and protease treatment were optimized to select the appropriate parameters in cell wall breaking. The effects of these 4 methods and the synergistic action of ultrasonic disruption and protease treatment were compared. The results showed that when the ultrasonic cleaning time was 40 min and ultrasonic disruption time was 50 min, the water content of slurry was 15% and the times of freezing and thawing was 3, and the protease treatment was carried out at 40℃ for 15 h with enzyme concentration 300 IU/g and pH 5.0, respectively, the extraction rates of yeast polysaccharides were the highest. The effect of protease treatment was the best among these 4 cell wall breaking methods, its extraction rate of polysaccharide was 149.81 mg/g and the cell wall broken rate was 53.49%. The effect of combined way was better than that of single treatment, but the synergistic action would destroy the integrity of polysaccharide's structure. So the protease treatment was thought an ideal cell wall breaking method of yeast. 相似文献
10.
试验旨在选择获得最大酵母多糖提取率的酵母菌破壁方法。以酵母多糖提取率与细胞破壁率为综合评定指标,首先对超声波破碎、超声波清洗、反复冻融、蛋白酶处理4种方法进行条件优化,选择最适破壁条件;然后将此4种单一的破壁方法与超声波破碎和蛋白酶处理协同方法相比较,确定获得最大多糖提取率的破壁方法。结果表明,当超声波清洗时间达到40 min、超声波破碎时间达到50 min时,酵母多糖提取率达到最大值;当菌泥加水量和冻融次数分别为15%与3次时,多糖提取率最大;当蛋白酶用量300 IU/g、酶解时间15 h、pH 5.0、处理温度40℃时,蛋白酶处理的多糖提取率最高。4种破壁方法中蛋白酶处理的效果最佳,对应的多糖提取率为149.81 mg/g,破壁率为53.49%。协同破壁处理的提取效果要优于单一的破壁方法,但考虑到协同作用对多糖结构的完整性构成威胁,将蛋白酶处理确定为最佳的酵母菌破壁方法。 相似文献
11.
多糖和寡糖的体外发酵特性及其对鸡盲肠微生物菌群的影响 总被引：1，自引：0，他引：1
本研究采用体外累积发酵产气法和16SrDNA指纹图谱鉴定技术研究了来自香菇、银耳和黄芪的天然免疫活性多糖(LenE,TreE和AstE)及酵母胞壁甘露寡糖(MOS)对鸡肠道微生物菌群及其发酵特性的影响。结果表明,三种多糖提取物的总糖含量均占干物质的60%以上,而MOS总糖含量在90%以上。多糖和寡糖具有不同的发酵模式;MOS、AstE和LenE三种糖的发酵模式相似,呈一阶段发酵模式;TreE呈两阶段的发酵模式。三种糖中,MOS和AstE发酵速度较TreE快。MOS和AstE在发酵后总VFA产量最高,pH最低;黄芪多糖发酵后产生较多的直链脂肪酸和较低的氨。这些多糖和寡糖提取物影响肠道微生物的活性和组成成分,体现在发酵模式和发酵终产物的显著改变上。以上研究结果表明,来自香菇、银耳和黄芪的天然免疫活性多糖(LenE,TreE和AstE)及酵母胞壁甘露寡糖(MOS)在体外发酵后,均具有显著改变鸡盲肠微生物发酵终产物的含量和盲肠微生物活性的作用。 相似文献
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本研究旨在探讨饲粮中添加酵母壁多糖对断奶仔猪生长性能和小肠黏膜形态结构的影响。试验采用单因素试验设计方法,选取180头遗传背景一致、健康状况良好、胎次和体重接近的21日龄断奶仔猪,随机分为4个组,每组5个重复,每个重复9头猪。4个组分别饲喂对照饲粮、0.15%酵母壁多糖饲粮、0.30%酵母壁多糖饲粮和0.45%酵母壁多糖饲粮。试验期21 d。结果表明:1)与对照组相比,饲粮中添加酵母壁多糖能够显著提高断奶仔猪平均日增重和平均日采食量(P0.05);酵母壁多糖有降低断奶仔猪腹泻率和料重比的趋势,但差异不显著(P0.05)。2)与对照组相比,饲粮中添加酵母壁多糖能够显著提高断奶仔猪空肠绒毛高度/隐窝深度值(P0.05),添加0.45%酵母壁多糖能够显著提高断奶仔猪空肠绒毛高度和十二指肠绒毛高度/隐窝深度值(P0.05)。由此可知,酵母壁多糖可提高断奶仔猪的生长性能,并改善小肠黏膜形态结构;综合生长性能、小肠黏膜形态及经济成本等指标,其在仔猪饲粮中的适宜添加量为0.30%。 相似文献
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Mycotoxins are structurally diverse fungal metabolites that can contaminate a variety of dietary components consumed by animals and humans. It is considered that 25% of the world crop production is contaminated by mycotoxins. The clinical toxicological syndromes caused by ingestion of moderate to high amounts of mycotoxins and their effect on the immune system have been well characterized. However, no particular attention has been focused on the effects of mycotoxins on the local intestinal immune response. Because of their location, intestinal epithelial cells (IECs) could be exposed to high doses of mycotoxins. As a component of the innate local immune response, intestinal epithelial cells have developed a variety of mechanisms which act to reduce the risk of infection by microorganisms or intoxication by toxic compounds. This review summarises the innate immune response developed by intestinal epithelial cells and reports the literature concerning the effects of mycotoxins on them. Particularly, the effects of mycotoxins on the maintenance of a physical barrier by epithelial cells will be discussed together with their effect on extrinsic protective components of the innate intestinal immunity: mucus secretion, antimicrobial peptide generation, IgA and pro-inflammatory cytokine release. 相似文献
15.
Polysaccharide is the major component of bacterial cell that plays a significant role in the interaction between bacteria and their hosts. It aids the identification of bacteria, imparting virulence to the bacteria and adjusting host's immune response as well. Advance genomics research has deciphered several different bacterial polysaccharides sharing a common biosynthesis mechanism. The study of polysaccharides is mainly based on sequence analysis and prediction of genome in combination with metabolite analyses that still requires a detailed study. Researchers are now further focusing on their biosynthetic pathways to unveil the mechanisms underlying the diversity of these bacterial polysaccharides along with the host-pathogen interaction. It will open new doors for vaccine development and other therapeutic methods against pathogenic bacteria, and also provide technical support to control disease and cure at molecular level. This review states the mechanisms and relevant problems of biosynthesis and in vitro biosynthesis of peptidoglycan,O-antigen and capsular polysaccharides,and summarizes the application of bacteria polysaccharides in the aspects of searching for candidate antigens and controlling the targets of pathogenic bacteria and exploring genetic evolution of bacteria and biological synthesis. 相似文献
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多糖是细菌细胞的主要组成部分,在细菌与宿主的相互作用中起到重要作用,在参与细菌与宿主的识别,帮助细菌产生毒力,调节宿主免疫反应等生物过程中扮演着重要的角色。随着基因组学的发展,人们发现尽管细菌多糖的种类很多,但它们的合成机制具有相似性。多糖生物合成的研究主要基于基因组的序列分析预测,结合代谢产物研究的基因分析,不够详尽。随着研究的深入,人们越来越关注细菌多糖的合成机制,这种机制的研究将为进一步阐明细菌多糖多样性的形成机制及与宿主间的相互作用机制奠定基础,为开发针对相应病原菌的新型疫苗和治疗方法,及进一步实现分子水平的相关疾病防控和资源开发提供技术支持。作者以肽聚糖、O-抗原和夹膜多糖为代表,阐述了其生物合成及体外生物合成机制的研究进展和相关问题,并总结了细菌多糖合成途径的研究在寻找候选抗原和控制病原细菌靶位以及研究细菌遗传进化和生物合成方面的作用。 相似文献
17.
L. Kissell S. Davidson B. A. Hopkins G. W. Smith L. W. Whitlow 《Journal of animal physiology and animal nutrition》2013,97(4):694-700
Three studies were conducted to determine the potential of experimental feed additives (EFAs), clays or non‐digestible yeast oligosaccharides, to reduce milk aflatoxin (AFM1) concentrations in lactating Holstein cows consuming aflatoxin‐contaminated diets. All studies included a pre‐treatment period and a 2‐week experimental period in a randomized block design. During the pre‐treatment period, cows received a total mixed ration (TMR) with no aflatoxin contamination. During both experimental weeks, all cows were fed a TMR containing aflatoxin‐contaminated corn. During experimental week 1, cows received no EFA’s in the TMR, but EFA’s were included in the TMR for the second experimental week. In studies 1 and 2, the experimental period consisted of 2 weeks each lasting 7 days with 12 cows per treatment. Aflatoxin M1 concentrations were analysed by HPLC for milk samples collected on days 5–7 and days 11–14. In various experiments, treatments included control (no EFA), 100 g/cow daily of experimental Lallemand® product, 10 g/cow daily of MTB‐100®‐2004, (Alltech, Inc.), 10 g/cow daily of MTB‐100®‐2006, (Alltech, Inc.), 10 g/cow daily of experimental Alltech® product (Alltech, Inc.) and 227 g/cow daily of Astra‐Ben 20® (AB‐20®; Prince Agri Products, Inc.). In study 3, the experimental period of 2 weeks each lasting 8 days and milk samples were collected from day 4 to 8 and day 11 to 16. Milk samples from study 3 were analysed for AFM1 concentrations by ELISA. For all experiments, changes in AFM1 concentrations because of the addition of EFA’s were calculated. Four of the five EFAs tested in this study had no significant effect on AFM1 concentrations. However, the addition of AB‐20® resulted in a significant decrease in AFM1 concentrations (60.4%). In summary, the addition of AB‐20® to the diet of cattle appears to be effective for significantly reducing AFM1 concentrations in the milk of cows fed an aflatoxin‐contaminated diet. 相似文献
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Ghosh TK Haldar S Bedford MR Muthusami N Samanta I 《Journal of animal physiology and animal nutrition》2012,96(2):275-284
The study compared the effects of an antibiotic growth promoter (AGP), yeast (Saccharomyces cerevisiae) and yeast cell wall (YCW) on performance, microbiology and histo-morphology of the small intestine and humoral immune responses in Ross 308 broilers. The treatments (eight replicates/treatment, n = 12/replicate) were negative control (NC, without AGP), positive control (PC, supplemented with bacitracin methylene disalicylate, 400 mg/kg), Y and YCW (supplemented with yeast and YCW, respectively, 1000 mg/kg). Live weight at 42 days improved (p = 0.086) in the PC, Y and YCW groups. Feed conversion ratio was better (p = 0.039) in the YCW group compared with the other groups. Antibiotic growth promoter in the PC group shortened the villi in duodenum (p = 0.044). Mucosal Escherichia coli number was higher in the PC group (p < 0.001), whereas in the digesta E. coli number was lower (p = 0.001) in the PC, Y and YCW groups in relation to the NC. Mucosal Salmonella populations increased (p = 0.0001) in the PC group, whereas in the digesta, all treatments reduced the Salmonella (p = 0.0001). Following oral challenge with Salmonella pullorum, YCW increased E. coli numbers on the mucosa (p < 0.001) whereas in the digesta the Y group had lower (p < 0.0001) number of E. coli. In the digesta, Salmonella count was lower in the YCW group compared with the other treatments (p < 0.01). Yeast cell wall -treated birds exhibited better (p < 0.05) humoral immune response against Newcastle disease which was far more persistent over time than in any other treatments. It was concluded that the yeast and the yeast cell wall may have effects identical to BMD on performance of broilers and thus may constitute an effective replacement strategy in the dietary regimens for broiler chickens. 相似文献
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水溶性酵母葡聚糖的制备及应用研究进展 总被引：2，自引：0，他引：2
啤酒酵母葡聚糖是一类免疫多糖,参与生物细胞的多种生命调节,可激活免疫细胞,调节机体免疫力,具抗菌消炎、抗病毒、抗肿瘤等功能,且毒副作用低,被称为生物效应应答剂。近年来,越来越多的学者开始研究和开发酵母葡聚糖。论文对酵母葡聚糖的结构、提取方法、结构修饰和应用进行了简述,对提取方法和结构修饰中的各种方法进行了综合比较和分析;并重点介绍了提高酵母葡聚糖的水溶性的方法及相对应的鉴定方法,这将为酵母葡聚糖的开发利用奠定一定的理论基础。除此之外,论文还对酵母葡聚糖的进一步开发利用进行了展望。 相似文献
20.
《The Journal of Applied Poultry Research》2008,17(4):471-475
A 42-d broiler pen trial was conducted to evaluate the effects of dietary mannan oligosaccharide (MOS) from either of 2 commercial products, Bio-Mos (Alltech Inc., Nicholasville, KY) or SAF-Mannan (S. I. LeSaffre, Cedex, France) each at 2 levels of inclusion on live performance. The MOS, derived from the outer portion of yeast cell walls, is reported to have several beneficial modes of action including 1) pathogen adsorption (agglutination); 2) improved intestinal integrity (e.g., villi height); and 3) immune modulation. Diets were fed in 3 phases, and treatments included a control, 2 Bio-Mos treatments (1.0 kg/ton in starter and 0 or 0.5 kg/ton in grower and finisher feeds), and 2 SAF-Mannan treatments (0.5 kg/ton in starter and 0 or 0.5 kg/ton in grower and finisher feeds), according to the manufacturers’ recommendations. Birds fed Bio-Mos at 1.0/0.5/0.5 (starter/grower/finisher) kg/ton diets had significantly greater BW at 42 d than birds fed control or SAF-Mannan-supplemented diets, whereas results for the Bio-Mos 1.0/0/0 kg/ton diets were intermediate. Supplementation of diets with Bio-Mos at 1.0/0.5/0.5 kg/ton may improve broiler BW at market ages compared with the unsupplemented diets. Feed consumption was lower from 0 to 21 d in the SAF-Mannan treatments compared with other treatments. No significant differences were found for feed conversion or mortality for any of the treatments. Overall, Bio-Mos had a greater effect on bird BW compared with the other variables measured. 相似文献