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1.
6株芽孢杆菌的生物学特性比较研究 总被引：4，自引：2，他引：2
以实验室分离保存的6株芽孢杆菌为材料,对其主要生物学特性进行了研究,包括产酶活力,对NaCl、牛胆盐、人工胃液和人工肠液的耐受性及对抗生素的敏感性。结果显示,枯草芽孢杆菌1、凝结芽孢杆菌和蜡样芽孢杆菌均能产生较高活性的中性蛋白酶和淀粉酶;2株枯草芽孢杆菌和凝结芽孢杆菌能耐较高浓度的NaCl;枯草芽孢杆菌2、凝结、纳豆和蜡样芽孢杆菌对牛胆盐的耐受性较强;除地衣芽孢杆菌外,其他5株芽孢杆菌对胃液和肠液的耐受性较好;6株芽孢杆菌均对常用饲用抗生素敏感。结果表明,枯草1、凝结、蜡样芽孢杆菌是优良的候选益生菌菌株。 相似文献
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本文通过平皿分离培养及生理生化反应，对桑园土壤中的芽孢杆菌分布及种类进行了分析，结果表明，在上层土和下层土中的芽孢杆菌分布及种类存在较大的差异，在１～５ｃｍ、５～１０ｃｍ土层中，芽孢杆菌占细菌总数的百分比分别为１３．３７％和２．３２％。共检出芽孢杆菌１５种，并将其中１１种确定到种，在土壤分布中占优势的种为枯草芽孢杆菌、巨大芽孢杆菌、地衣芽孢杆菌、蜡样芽孢杆菌、蕈状芽孢杆菌和苏云金芽孢杆菌。 相似文献
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研究耐药菌株和敏感菌株的竞争关系,为寻找降低耐药细菌危害的方法提供理论依据。应用改良影印培养法,考察耐氨苄西林大肠杆菌菌株(G414)起始比例、益生菌种类和营养水平对人造微生物群落中G414菌落比例变化的影响。结果表明:人造群落中耐药菌株生存竞争能力大于敏感菌株(ATCC 25922),其比例在1~7 d均逐渐上升;高初始比例组的耐药菌株比例从33%上升至64%,绝对值增加31%,超过敏感菌株成为群落中的优势菌,低初始比例组从10%上升至43%;枯草芽孢杆菌和地衣芽孢杆菌在1~7 d能够显著放缓耐药株在群落中比例的升高趋势(P0.05),蜡样芽孢杆菌除开始两天外,可极显著地降低耐药菌株的比例(P0.01);在高(100%)、中(10%)、低(1%)营养条件下,耐药菌株比例均逐步升高,中营养水平组的比例上升最快。耐氨苄西林大肠杆菌菌株并没有因携带耐药基因而升高其在无药环境中的竞争适应度代价,反而获得了在正常营养和低营养以及多物种竞争条件下的某种竞争优势,逐步成为人造群落中的优势菌群,传播出去,可能对公共卫生安全造成较大威胁;枯草芽孢杆菌和地衣芽孢杆菌只能降低耐药菌株比例上升的趋势,而蜡样芽孢杆菌可极显著地抑制耐药菌株的生长,促使其消亡,加以开发利用,或许能降低养殖环境中某些耐药菌的数量。 相似文献
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现有的饲料添加剂目录中,枯草芽孢杆菌和地衣芽孢杆菌均被允许用于养殖动物。因此,本研究选择实验室收藏的枯草芽孢杆菌和地衣芽孢杆菌按不同比例制成复合菌液协同发酵桑叶饲料,并检测发酵第7天、第28天和56天的桑叶品质。桑叶青贮发酵后,发现枯草芽孢杆菌/地衣芽孢杆菌都具有降解纤维、分解脂肪,提高粗蛋白含量的能力,其中,H2组的粗纤维含量在发酵第56天较对照组下降了12.69%,只占(12.217±0.039)%,说明地衣芽孢杆菌分解纤维的能力可能相对较强,H3组的粗脂肪含量在发酵第56天较对照组下降了20.99%,只占(5.884±0.003)%,说明枯草芽孢杆菌分解脂肪的能力可能相对较强,不同比例的复合芽孢杆菌H1、H2和H3组的粗蛋白含量在发酵第56天分别增加8.96%、7.24%和3.72%,说明两种芽孢杆菌均具有提高青贮桑叶蛋白质含量的能力,能够提高饲料营养品质的效果。 相似文献
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研究旨在比较4种不同来源木聚糖酶基因在大肠杆菌E.coli BL21中表达后的酶活等性质,为生产中筛选高表达量及耐极性木聚糖酶基因提供依据。根据已发表的木聚糖酶基因序列设计引物,分别扩增出浸麻芽孢杆菌(B.macerans)B3、地衣芽孢杆菌(B.licheniformis)B6、蜡样芽孢杆菌(B.cereus)B10和枯草芽孢杆菌(B.subtilis)B12的木聚糖酶基因片段,经克隆表达后获得4种工程菌。经培养和IPTG诱导后进行SDS-PAGE电泳检测及酶特性分析。测序结果表明,4个基因的开放阅读框均为642 bp。其中前3种木聚糖酶基因均为首次报道。4种重组木聚糖酶在55℃下的酶活分别为:36.16、3.85、7.22、98.98 U/ml。4种重组木聚糖酶的最适反应温度均在50~60℃,且枯草芽孢杆菌木聚糖酶最为耐热。结果提示,枯草芽孢杆菌来源的木聚糖酶具有较高的酶活和较好的耐热性。 相似文献
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生牛乳杀菌后残留少数芽孢具有极强耐受性,在一定条件下芽孢大量繁殖,使牛乳发生变质,严重影响产品品质和消费者健康。采集并选择含有芽孢杆菌的生牛乳样品,进行需氧芽孢杆菌和嗜热需氧芽孢杆菌的分离,通过形态学、生理生化和分子生物学方法对分离菌株进行鉴定,同时对分离到的嗜热需氧芽孢杆菌进行耐热性研究。结果表明：共分离出10?株芽孢杆菌,其中3?株为嗜热需氧芽孢杆菌,7?株为需氧芽孢杆菌,其中能耐受115?℃/15?min热处理的有凝结芽孢杆菌和克劳氏芽孢杆菌,121?℃/20?min热处理可以将生牛乳中芽孢杆菌全部杀灭,致死率达100%,芽孢数下降4?个数量级;生牛乳中芽孢杆菌的优势菌有枯草芽孢杆菌、蜡样芽孢杆菌、短小芽孢杆菌、地衣芽孢杆菌、环状芽孢杆菌、明胶芽孢杆菌、解淀粉芽孢杆菌、凝结芽孢杆菌和克劳氏芽孢杆菌;耐热性较强的有凝结芽孢杆菌和克劳氏芽孢杆菌,最高能耐受115?℃/15?min热处理。 相似文献
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[Objective] The paper was to isolate and identify probiotics in the intestine of laying hens. [Method] The intestinal probiotics in laying hens at peak period were isolated using conventional separation methods; the physical and chemical properties of target strains and in vitro antibacterial effects were measured. Moreover, the safety test of chicks was conducted. [Result] Four strains of lactobacillus were isolated from the jejunum of laying hens, including Lactobacillus plantarum, Bacillus acidophilus, L. delbrueckii subsp. Delbrueckii and L. delbrueckii subsp. Lactis, and their inhibition zone diameters were 18.30, 16.07, 11.45, 17.26 mm, respectively. One strain of Lactobacillus, L. brevis, was isolated from the cecum, with the inhibition zone diameter of 10.26 mm. Three strains of bacillus were isolated from the cecum, including Bacillus subtilis, B. cereus and B. licheniformis, and their inhibition zone diameters were 9.25, 8.46 and 8.37 mm, respectively. Daily drinking 2 billion units of viable bacteria was the safe dosage for chicks. [Conclusion] Eight strains of probiotics had certain inhibitory effect on Escherichia coli O_2, and had no toxic side effects to chicks. Lactobacillus had strong antibacterial effect on E. coli O_2, while the antibacterial effect of bacillus was relatively weak. 相似文献
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LIU Xiu-xia XU Hai-yan XIN Guo-qin LI Jin-min ZHAO Ying SUN Xue-sen GU Wei 《中国畜牧兽医》2017,44(8):2333-2341
The purpose of this study was to investigate the property of antibacterial, production of enzymes, tolerance and in vitro digestibility of 11 Bacillus subtilis strains.9 Bacillus subtilis strains were screened out according to antibacterial property and production of enzymes. After tests of heat, pH tolerance, artificial gastrointestinal fluid and pig bile salt,6 Bacillus subtilis strains had good performance in simulation of animal digestive tract and strong heat tolerance in the process of production. Meanwhile, 5 strains BLCC1-1, BLCC1-2, BLCC1-3,BLCC1-4 and BLCC1-6 had good digestion effects on different combinations of feeds. Based on the above results,it suggested that BLCC1-1, BLCC1-2, BLCC1-4 and BLCC1-6 had excellent production of enzymes, tolerance and in vitro digestibility, which might be suitable for using as feed additives and further research. 相似文献
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Certain properties of 22 Bacillus cereus strains isolated from different foods and food poisoning episodes were investigated in order to evaluate possible différences between strains isolated from diarrhoeal and vomiting type food poisoning outbreaks.None of the strains isolated from vomiting type episodes produced acid from salicin and mannose, whereas 80 and 40 % of the strains from diarrhoeal type outbreaks were positive, respectively. No association between the antibiotic sensitivity pattern or the fatty acid composition and the source of a strain could be found, although some strains differed from the general pattern of B. cereus in some instances. No significant differences in the production of the skin factor between strains isolated from the two types of outbreaks were found either. The findings of this study support the observation that the food environment itself essentially affects the enterotoxin formation of B. cereus. 相似文献
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试验旨在研究11株枯草芽孢杆菌的抑菌、产酶、耐受性和体外消化率等益生特性。从11株枯草芽孢杆菌中初筛得到9株体外抑菌特性和产酶特性均较好的芽孢杆菌;经过热、人工胃肠液、胆盐等耐受性复筛,结果表明9株芽孢杆菌中有6株对胆盐、胃酸、肠液等人工模拟的消化道内环境和生产过程中的热耐受性较强;经模拟动物体消化道的试验结果表明,9株芽孢杆菌中有5株（BLCC1-1、BLCC1-2、BLCC1-3、BLCC1-4、BLCC1-6）对不同组合饲料的消化效果较好。综合以上试验结果,既表现出较好的产酶、抑菌和耐受性,又对组合饲料有良好的消化效果的枯草芽孢杆菌有BLCC1-1、BLCC1-2、BLCC1-4和BLCC1-6,这4株枯草芽孢杆菌具有作为饲料添加剂应用于畜禽饲料中的潜力,可进一步开展研究。 相似文献
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K Shinagawa S Otake N Matsusaka S Sugii 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(3):443-446
Vacuole response in HEp-2 cells was induced with culture supernatants of Bacillus cereus strains isolated from outbreaks of vomiting- and diarrheal-type food poisoning grown in rice flour and laboratory media. High vacuole response was obtained with culture supernatants of B. cereus strains isolated from vomiting-type food poisoning grown in cooked rice suspension or on a cooked rice plate, whereas no response was obtained with those of the same strains grown in brain heart infusion and trypto-soya broth media. The vacuole activity appeared only after spore formation of B. cereus. The activity was stable to proteolytic enzymes, heating, and exposing to pH 2.0 and 11.0. Of 124 strains isolated from B. cereus food poisoning that were tested, the vacuole activity was observed by 68 of 110 (61.8%) of the strains isolated from the vomiting-type food poisoning but not by all strains (14 strains) from diarrheal-type ones. Moreover, the vacuole response in the HEp-2 cells was found to be induced by 56 of 76 (73.7%) of the serotype H-1 strains isolated from vomiting-type food poisoning. 相似文献
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植物根际促生菌对两种真菌病害病原的抑制作用及其鉴定 总被引：1，自引：0，他引：1
利用钼蓝比色法、乙炔还原法和高效液相色谱法分别测定了分离自5种植物根际的19株细菌溶磷、固氮和分泌生长素特性;用平板对峙生长法测定了19株细菌对黄瓜枯萎病菌和小麦根腐病菌的抑制作用;结合菌株形态、生理生化反应,利用分子生物学方法鉴定了其中8株优良细菌。结果表明,菌株Bacillus subtilis LM4-3固氮酶活性较高[244.88 nmol C2H4/(mL·h)];菌株B. subtilis LHS11-1溶磷能力较强(205.77 mg/L);菌株PGRS-3分泌IAA能力较好(40.78 μg/mL)。5株菌株能够有效拮抗黄瓜枯萎病菌,其中B. subtilis FX2-1抑菌活性较强(活菌抑制率69.07%,发酵液抑制率51.73%)。7株菌株能够有效拮抗小麦根腐病菌,其中B. subtilis FX2-1抑菌活性较强(活菌抑制率 78.17%),B. subtilis LHS11-1发酵液抑制率高达81.52%。其他具有较好促生或拮抗上述两种病原真菌的菌株经鉴定,分别属于蜡样芽孢杆菌(B. cereus,菌株XX1)、短小芽孢杆菌(B. pumilus,菌株F1-4和LX22)、简单芽孢杆菌(B. simplex,菌株XX6)和荧光假单胞杆菌(Pseudomonas fluorescens,菌株XX5)。 相似文献
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Nieminen T Rintaluoma N Andersson M Taimisto AM Ali-Vehmas T Seppälä A Priha O Salkinoja-Salonen M 《Veterinary microbiology》2007,124(3-4):329-339
To elucidate the occurrence of heat-stable toxin-producing strains among mastitic Bacillus isolates, 100 milk samples of mastitic cows from different parts of Finland were screened. Bacillus was identified as the major organism in 23 samples. Toxinogenic Bacillus isolates identified by sperm cell motility inhibition assay were isolated from six samples. Four isolates belonged to the species Bacillus pumilus and two to Bacillus licheniformis. The toxic substances were heat-stable and soluble to methanol thus being of non-protein nature. The methanol extracted substances disrupted the sperm cell plasma membrane permeability barrier at exposure concentrations of 1-15 microg ml(-1) (B. pumilus) or 20-30 microg ml(-1) (B. licheniformis). The toxic properties of the two mastitic B. licheniformis strains were similar to those of B. licheniformis strains known to produce the lipopeptide lichenysin A and the synthetase genes lchAA, lchAB and lchAC for lichenysin were found in the mastitic strains by PCR. Toxin synthetase genes for the syntheses of lichenysin or surfactin were searched but not found in the toxic B. pumilus strains. The ribopatterns of the mastitic B. pumilus and B. licheniformis isolates were similar to those of the toxinogenic strains described earlier from food poisoning incidents and contaminated indoor air. B. licheniformis and B. pumilus survive pasteurization and other heat treatments as spores. Toxin-producing strains of these species in the dairy production chain may thus be of food safety concern. 相似文献
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本试验旨在研究不同组合益生菌对育成期水貂生长性能和营养物质消化率及氮平衡的影响。选择96只60日龄、健康状况良好的水貂,随机分为4组,每组24只,公、母各半。对照组饲喂基础日粮,试验1、2、3组分别在基础日粮中添加0.06 g地衣芽孢杆菌+0.06 g枯草芽孢杆菌、6 g安琪酵母+12 mL乳酸菌、0.06 g地衣芽孢杆菌+0.06 g枯草芽孢杆菌+6 g安琪酵母+12 mL乳酸菌。在水貂育成期内进行饲养与消化代谢试验,分析不同组合益生菌对水貂平均日采食量、平均日增重、料重比、粗蛋白质和粗脂肪的消化率及沉积氮、蛋白质生物学价值和净蛋白质利用率的影响。结果表明,与对照组相比,试验1组公貂的干物质消化率和试验2组公貂的脂肪消化率显著下降(P<0.05),但不同组水貂的生长性能和氮平衡及母貂的营养物质消化率未受到益生菌的影响(P>0.05)。提示,日粮中添加益生菌不会显著改善育成期水貂的生长性能、营养物质消化率及氮平衡,故在水貂健康的前提下,无需在育成貂日粮中添加益生菌。 相似文献
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The pathogenicity of the metabolites of B. cereus was determined by bioassays with white mice, chick embryos, rabbits, and kittens. Cell-free filtrates of the cultures of several strains of B. cereus were used for application; in the mice the application was done i. v., i. p. and p. o., in the chick embryos via the allantoic sac, in the kittens p. o. and i. p., in the rabbits via tied-up sections of the small intestine by the loop-test method. It was revealed that some strains of B. cereus produced substances of exotoxin nature under suitable conditions. White mice and chick embryos were the best materials for their detection. 相似文献
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采用稀释平板法从表面消毒的甘农三号紫花苜蓿种子中分离、纯化出8株细菌(ZSR9~16),测定其产IAA、固氮、溶磷和分解纤维素生物学功能,明确6株菌(ZSR9~12和ZSR14~15),它们具有功能多样性,均能产IAA、溶磷、固氮和分解纤维素,菌株ZSR9在它们中的所有生物功能最强;菌株ZSR13具有较弱的产IAA的能力;菌株ZSR16具有较强的产IAA、溶磷、固氮和分解纤维素的能力。通过对这8株菌的菌体形态描述、表型和16S rDNA鉴定,它们分别属于3个属的8种菌。其中芽孢杆菌属(Bacillus)的有6株:枯草芽孢杆菌(B. subtilis) ZSR9、沙福芽孢杆菌(B. safensis) ZSR10、莫海威芽孢杆菌(B. mojavensis) ZSR11、地衣芽孢杆菌(B. licheniformis) ZSR12、短小芽孢杆菌(B. pumilus) ZSR14和深褐芽孢杆菌(B. atrophaeus) ZSR15;ZSR13为肠杆菌属(Enterobacter sp.)和ZSR16为土地芽孢杆菌属(Terribacillus sp.)。这些菌种的得到将为其开发利用奠定菌种资源基础。 相似文献
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枯草芽孢杆菌MA139类细菌素抑菌活性的研究 总被引：1，自引：0，他引：1
为测定枯草芽孢杆菌MA139产生的类细菌素的抑菌活性。本试验采用管碟法对枯草芽孢杆菌MA139产生的类细菌素对多株革兰氏阳性菌、革兰氏阴性菌和真菌的抑菌活性进行测定。结果表明:类细菌素不但对芽孢杆菌属的其他菌种有抗菌活性,对病原菌和霉菌也有拮抗作用;不同指示菌对类细菌素的敏感性不一样,其中金黄色葡萄球菌对其最敏感。该类细菌素具有广谱抗菌作用,有作为畜禽饲料添加剂的潜力。 相似文献