益生菌体外增殖因子的初步研究

目的研究单糖、pH、温度及时间对青春双歧杆菌、长双歧杆菌和类干酪乳杆菌体外增殖的影响。方法用甘露糖、半乳糖、山梨醇及果糖代替MRS中的葡萄糖,筛选出每种细菌的最适碳源。以此为基础,选择其最佳初始pH、培养温度、碳源添加量及培养时间。结果青春双歧杆菌、长双歧杆菌和类干酪乳杆菌的最适碳源分别为葡萄糖、甘露糖和半乳糖;最佳初始pH为6.0、7.0和6.0;培养温度为42、30和30℃;碳源添加量为20、15和25 g/L;培养时间都为28-48 h。结论益生菌具有不同的最适增殖条件,本文研究结果为优化益生菌的生长条件提供了基础数据。     

双歧杆菌对失血后肠源性感染的预防作用

本文观察双歧杆菌对失血后肠源性感染的预防作用,将大鼠分为假处理、失血、双歧杆菌＋失血,新霉素＋失血４组。后两组实验前分别灌注双歧杆菌或新霉素,假处理动物麻醉插管不放血,后３组动物放血２ｏ％,６ｈ后每组１０只动物活杀取样。发现：失血组大鼠１０ｈ存活率降低,血浆ＥＴ、ＩＬ—１升高,细菌培养阳性标本增多,小肠杆／球菌比值增大,与假处理组相比差异显著。双歧杆菌治疗组大鼠时间存活率增加,血浆ＥＴ、ＩＬ—１无明显升高,细菌培养阳性标本减少,杆／球菌比例正常,与失血组相比差异显著。新霉素治疗组上述各项指标与失血组相比无显著改善。提示双歧杆菌能有效地预防失血后肠源性感染。     

Comparison of carbohydrate substrate preferences in eight species of bifidobacteria

Eight species of bifidobacteria were tested for their abilities to grow on a range of monosaccharides (glucose, arabinose, xylose, galactose and mannose). In contrast to the other sugars, glucose and galactose were utilized by all species and, in general, specific growth rates were highest on these sugars. Different substrate preferences were observed between species when the bacteria were grown in the presence of all five monosaccharides. For example, glucose and xylose were coutilized by Bifidobacterium longum, whereas glucose repressed uptake of all other sugars in B. bifidum and B. catenulatum. Galactose was the preferred substrate with B. pseudolongum. In B. angulatum, glucose and galactose were utilized simultaneously. B. breve did not grow on arabinose when this sugar provided the sole source of energy. However, glucose and arabinose were preferentially taken up during growth on sugar mixtures.     

大豆低聚糖对肠道双歧杆菌和肠杆菌的促生长作用

目的:观察大豆低聚糖和所含糖对肠道菌群中双歧杆菌、肠杆菌体外促生长作用。方法:按1％大豆低聚糖、0．36％水苏糖、0．52％蔗糖、0．11％棉子糖含量配制培养液,分别接种各试验菌株,在0、12、24小时测定各培养液吸光度A值(分光光度计．550nm)和pH值。结果:经24小时培养,加大豆低聚糖的双歧杆菌标准株和临床分离株培养液A值分别为>1．5和1．307,大于肠杆菌标准株和临床分离株的1．1和1．173,而其pH值小于肠杆菌;加水苏糖的双歧杆菌培养液A值为1．47,大于蔗糖的1．4和棉子糖的0．53。结论:大豆低聚糖促双歧杆菌生长作用大于促肠杆菌生长,水苏糖是促双歧杆菌增殖生长的主要成分。     

Bifidobacterium reuteri sp. nov., Bifidobacterium callitrichos sp. nov., Bifidobacterium saguini sp. nov., Bifidobacterium stellenboschense sp. nov. and Bifidobacterium biavatii sp. nov. isolated from faeces of common marmoset (Callithrix jacchus) and red-handed tamarin (Saguinus midas)

Five strains of bifidobacteria were isolated from faeces of a common marmoset (Callithrix jacchus) and a red-handed tamarin (Saguinus midas). The five isolates clustered inside the phylogenetic group of the genus Bifidobacterium but did not show high sequence similarities between the isolates and to known species in the genus by phylogenetic analysis based on 16S rRNA gene sequences. Sequence analyses of dnaJ1 and hsp60 also indicated their independent phylogenetic positions to each other in the Bifidobacterium cluster. DNA G+C contents of the species ranged from 57.3 to 66.3 mol%, which is within the values recorded for Bifidobacterium species. All isolates showed fructose-6-phosphate phosphoketolase activity. Based on the data provided, the five isolates represent five novel species, for which the names Bifidobacterium reuteri sp. nov. (type strain: AFB22-1(T) = JCM 17295(T) = DSM 23975(T)), Bifidobacterium callitrichos sp. nov. (type strain: AFB22-5(T) = JCM 17296(T) = DSM 23973(T)), Bifidobacterium saguini sp. nov. (type strain: AFB23-1(T) = JCM 17297(T) = DSM 23967(T)), Bifidobacterium stellenboschense sp. nov. (type strain: AFB23-3(T) = JCM 17298(T) = DSM 23968(T)) and Bifidobacterium biavatii sp. nov. (type strain: AFB23-4(T) = JCM 17299(T) = DSM 23969(T)) are proposed.     

分子信标-实时 PCR法快速检测双歧杆菌的研究

为建立双歧制品中双歧杆菌快速、敏感、特异的检测方法,根据双歧杆菌16SrRNA/16SrDNA基因设计合成了双歧杆菌属特异性引物和分子信标探针,建立了快速检测双歧杆菌的分子信标-实时PCR检测方法,并对反应条件进行优化。检测方法重复性好,批内和批间变异系数均小于5%;特异性强,扩增曲线呈现明显的S型,无非特异性扩增;灵敏度高,是普通PCR的100倍,对纯双歧杆菌DNA的检出限为5.7fg/PCR反应体系,纯双歧杆菌菌液的检出限为2×103CFU/mL;线形范围宽,起始模板数在2×108CFU/mL～2×104CFU/mL之间具有良好的线性关系,相关系数大于97%。该方法具有灵敏、特异、简便和快速的特点,可用于对双歧杆菌原位菌数的定量检测。     

双歧杆菌活菌制剂治疗烧伤腹泻的临床观察与分析

本研究采用双歧杆菌活菌制剂治疗烧伤后腹泻病人２６例,发现腹泻时患者肠道菌群发生明显变化：总菌量下降,厌氧菌中的双歧杆菌、类杆菌的数量明显减少,念珠菌的数量明显升高,厌氧菌与需氧菌比例下降,发生菌群失调。喂服双歧杆菌活菌制剂后,双歧杆菌数量增加,需氧、厌氧菌比例下降,患者失调的肠道菌群趋向正常,腹泻停止。双歧杆菌的服用重建了肠道菌群微生态平衡,达到治疗腹泻的目的     

健康人肠道双歧杆菌和大肠杆菌数量在不同季节的动态观察

本文研究了季节因素对肠道重要菌群双歧杆菌和大肠杆菌的影响。在春、夏、秋、冬四季分别定量检测Ｔ２０名健康青年粪便中的上述两种菌,结果表明：两种细菌数值均有明显的季节变动规律,双歧杆菌秋季显著高于春、夏冬三季;大肠杆菌夏季显著高于冬、春季,而与秋季的差异无显著意义。ｚＬ歧杆菌与大肠杆菌在一年四季中的比值也有明显的季节特征,即秋季明显高于其它三季。     

丽珠肠乐（回春生）对肝硬化的疗效观察

丽珠肠乐（回春生）为双歧杆菌活菌制剂,给７３例肝硬化失代期病人口服２２～６７天。治疗前后分别检测血内毒素含量及肝功能,观察其疗效。结果表明本制剂对肝硬化的疗效明显,总有效率为７９．４５％,其中内毒素水平治疗后明显下降,与治疗前比较,Ｐ＜０．０１,有效率为８７．６７％。肝功能各指标有不同程度的改善,有效率７８．０８％。说明回春生是当代最新的微生态调节剂。     

Modulation of a specific humoral immune response and changes in intestinal flora mediated through fermented milk intake

Abstract This study was undertaken to elucidate whether eating a fermented milk containing Lactobacillus acidophilus La1 and bifidobacteria could induce changes in intestinal flora and modulate the immune response in man. Volunteers consumed a fermented milk containing L. acidophilus La1 and bifidobacteria over a period of three weeks during which an attenuated Salmonella typhi Ty21a was administered to mimic an enteropathogenic infection. A control group ate no fermented foods but received the S. typhi Ty21a. Faecal flora analyses showed an increase in L. acidophilus and bifidobacterial counts during fermented milk intake. The specific serum IgA titre rise to S. typhi Ty21a in the test group was > 4-fold and significantly higher ( P = 0.04) than in the control group. An increase in total serum IgA was also observed. These results indicate that lactic acid bacteria which can persist in the gastrointestinal tract can act as adjuvants to the humoral immune response.