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为了研究ECLIPSE 50检测试剂盒对牛奶中Nisin Z残留检测的可行性,在无抗奶中添加Nisin标准品,测定ECLIPSE 50检测试剂盒对牛奶中Nisin的检测极限,并对Nisin乳房灌注剂治疗乳房炎病例牛奶中的Nisin Z残留进行了分析.结果表明:ECLIPSE 50检测试剂盒对牛奶中Nisin的检测极限为... 相似文献
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在MRS平板上，采用琼脂扩散法测定了Nisin对Lactobacillus acidophilus La-5和Bifidobacterium bifidum Bb-12生长的抑制作用。当Nisin浓度≥50ug/ml时，对Lactobacillus acidophilus La-5表现出强烈的抑制作用，而Bifidobacterium bifidum Bb-12则几乎不生长，即使Nisin的浓度仅为25ug/ml，当L.acidophilus La-5和B.bifidum Bb-12单独或两者共同在37℃发酵10％（w/w)还原脱脂奶时，脱脂奶中添加的50ug/ml Nisin对B.bifidum Bb-12表现出杀菌作用，而对L.acidophilus La-5则为抑菌作用。当延长培养时间后。L.acidophilus La-5的存在可以降低Nisin对B.bifidum Bb-12的致死作用。 相似文献
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高通量测序分析Nisin对腹泻小鼠肠道菌群的影响 总被引：1，自引：0，他引：1
采用高通量测序研究乳酸链球菌素(Nisin)对腹泻小鼠肠道菌群结构的影响。通过腹腔灌注E.coli O1建立腹泻病小鼠模型,通过动物体内保护率试验筛选出最佳药物剂量,将小鼠随机分为空白对照组、阴性对照组、氨苄青霉素、盐酸环丙沙星组和Nisin组。连续灌胃15d,收集盲肠粪便,采用高通量测序对5组样品进行分析。结果表明:1)E.coli O1可使腹泻小鼠十二指肠绒毛断裂;Nisin可增加淋巴细胞百分比,起到增强免疫的目的。2)通过小鼠保护率试验筛选出Nisin最佳剂量(0.002g·mL-1),其保护率为37.5%,低于氨苄青霉素(50%)和盐酸环丙沙星组(50%)。3)通过盲肠菌落计数,Nisin中大肠杆菌和肠球菌的数量显著低于阴性对照组(P0.05),尤其以Nisin组中肠球菌的数量最低;Nisin组中乳酸杆菌的数量显著高于其他各组(P0.05)。4)Nisin组中样品菌群多样性指数(ACE=1 417.25,Chao1=1 378.45,Shannon=7.56)显著高于阴性对照组(ACE=969.54,Chao1=340.29,Shannon=6.63),另外,腹泻小鼠肠道菌群结构存在显著差异。5)在门和属水平上,Nisin组中Bacteroidetes(拟杆菌门)最低,Firmicutes(厚壁杆菌门)、Clostridium(梭状芽胞杆菌)、Akkermansia属和Lactobacillus(乳杆菌属)所占比例最高,且高于其他各组。Nisin可增强腹泻小鼠免疫功能,增加肠道内有益菌的数量,减少有害菌数量;摄入适量的Nisin可以调控肠道内菌群比例。 相似文献
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在MRS平板上,采用琼脂扩散法测定了Nisin对Lactobacillus acidophilus la-5和Bifidobacterium bifidum Bb-12生长的抑制作用。当Nisin浓度≥50ug/ml时,对Lactobacillus acidophilus la-5表现出强烈的抑制作用,而Bifidobacterium bifidum Bb-12则几乎不生长,即使Nisin的浓度仅为25ug/ml;当L.acidophilus la-5和B.bifidum Bb-12单独或两者共同在37℃发酵10％(w/w)还原脱脂奶时,脱脂奶中添加的50ug/ml Nisin对B.bifidum Bb-12表现出杀菌作用,而对L.acidophilus La-5则为抑菌作用。当延长培养时间后,L.acidophilus La-5的存在可以降低Nisin对B.bifidum Bb-12的致死作用。 相似文献
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Nisin抗菌肽治疗奶牛无乳链球菌性隐性乳房炎后主要乳成份的变化 总被引：1，自引：0，他引：1
将36头无乳链球菌引起的隐性乳房炎奶牛分成试验组和对照组,每组18个病例.试验组奶牛用Nisin抗菌肽经患病乳房内灌注,每天1次,连续治疗3 d,对照组奶牛不治疗.分别采集治疗前和治疗后1、3、5周的奶样进行细菌学检查,体细胞含量测定和乳成份分析.结果表明,经Nisin治疗后,细菌阳性乳区数和体细胞教(SCC)大于500 000/mL乳区数量均显著降低,牛奶中脂肪、蛋白质、乳糖和总固体含量有升高趋势,尤其是蛋白质和乳糖的含量显著高于治疗前.由此可见,Nisin乳房内注入对于奶牛无乳链球菌性隐性乳房炎具有良好的治疗作用. 相似文献
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为构建乳酸菌Nisin诱导表达载体,实现外源目的基因在乳酸菌中的可控表达,本研究以产Nisin乳酸乳球菌染色体DNA为模板,采用PCR技术扩增双组份调控元件nisRK基因和诱导型启动子nisA基因,并克隆至乳酸菌-大肠杆菌穿梭质粒pW425et中,以nisA基因替换原组成型启动子P32,构建乳酸菌Nisin诱导表达载体pW425N。为检测载体的诱导表达功能,以gfp基因作为报告基因,构建重组表达载体pW425N-gfp,以分离自仔猪肠道内嗜酸乳杆菌为受体菌,电转化法制备重组乳酸菌pW425N-gfp/L.acidophilus。结果表明,重组载体能够在Nisin诱导下表达目的荧光蛋白,并且最佳Nisin有效浓度为30 ng/mL,最佳诱导时间为3 h。该表达载体的构建为外源功能性蛋白在乳酸菌中的诱导表达奠定基础。 相似文献
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天然食品防腐剂Nisin及其在乳品工业中的应用 总被引：1，自引：0，他引：1
天然食品防腐剂Nisin是一种乳酸菌细菌素。主要介绍了Nisin的发现研究历史、理化性质、抑菌谱、抑菌机理、安全无毒性及其在乳品工业中的应用。 相似文献
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《科技视界》2015,(14)
目的 :通过对生物乳酸钙豆腐的保质观察及乳酸链球菌素(Nisin)、脱氢乙酸钠对生物乳酸钙充填豆腐保质期的影响,探索生物乳酸钙充填豆腐的保质技术。方法:在点脑时在豆浆中加入Nisin、脱氢乙酸钠,同时做空白对照,在不同的保藏条件下,以菌落总数、大肠菌群和感官评价作为评价指标观察豆腐品质变化。结果:空白组和添加脱氢乙酸钠组杀菌后在37℃和常温下很快变质,冷藏条件下可保藏半年;添加Nisin组杀菌后在37℃恒温条件下可存放1周,常温下可保藏达一个月,冷藏条件下可保藏半年,且豆腐弹性较好,色泽均匀有光泽,口感细腻爽滑。结论:生物乳酸钙充填豆腐在冷藏条件下可保藏半年,Nisin对延长其货架期有明显的效果。 相似文献
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Joanna Ma&#x;aczewska Edyta Kaczorek‐&#x;ukowska Roman Wjcik Wojciech R&#x;kawek Andrzej K. Siwicki 《Journal of animal physiology and animal nutrition》2019,103(3):882-893
Nisin, a lantibiotic bacteriocin, has been used for years as a natural food preservative. In addition to its antimicrobial activity, nisin also shows immunomodulatory properties, and the nisin‐producing Lactococcus lactis strain has been successfully tested as a probiotic in weaned piglets. However, the impact of nisin on porcine immune cells has not yet been explored. The objective of the present study was to examine the in vitro immunomodulatory effect of nisin on porcine peripheral blood leucocytes. The whole heparinized blood samples or freshly isolated peripheral blood mononuclear cells (PBMCs) were incubated with different nisin concentrations (0, 1.56, 3.125, 6.25, 12.5, 25 or 50 µg/ml) for 1, 24, 48 or 72 hr. Escherichia coli bacteria were used to stimulate blood phagocytes, while concanavalin A and lipopolysaccharide from E. coli were used as mitogens. Control cells remained unstimulated. MTT colorimetric assay was used to evaluate PBMCs viability and mitogenic response. Phagocyte activity and T‐cell proliferation were measured by flow cytometry. Flow cytometer was also used for immunophenotyping of T cells. Cytokine levels in the culture media were determined using commercial immunoassay (ELISA) kits. The highest concentration of nisin exhibited proliferative activity (p ? 0.05), stimulated interleukin‐1 beta (IL‐1β) and interleukin‐6 (IL‐6) production (both at p ? 0.001), and increased the percentage of CD4+CD8+ T cells (p ? 0.001) among unstimulated leucocytes. After cell stimulation, however, the highest nisin concentration showed antiproliferative activity (p ? 0.05), decreased phagocytic functions (p ? 0.05) and inhibited the synthesis of IL‐6 (time‐ and concentration‐dependent effect). As a typical bacterial product, nisin had a stronger impact on innate immune cells, and its effect on T cells was likely a consequence of the modulation of the activity of antigen‐presenting cells. Nisin may be a good candidate as an immunomodulator in pig breeding. 相似文献
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The objective of this study was to investigate the effect of nisin and monensin on rumen fermentation of diets containing hay and barley (80:20%) in artificial rumen (Rusitec system). The Rusitec system consisted of four fermentation vessels (V1, V2, V3, V4): V1 was without additives (control), V2 received daily 2 mg of nisin, V3 involved 5 mg of monensin and V4 combination of 2 mg of nisin with 5 mg of monensin. After an adaptation period (7 days), the fermentation parameters were determined for six consecutive days. Compared to control diet, the addition of nisin resulted in an increase (P < 0.05) of hemicellulose degradation, acetate, propionate (mmol.day-1) production and energetic efficiency of VFA (E), decrease of butyrate production. Nisin had no effect on dry matter (DM), organic matter (OM), cellulose and detergent fiber degradation, production of total gas, methane and efficiency of microbial synthesis. The addition of monensin resulted in an decrease of DM, OM (P < 0.05), cellulose, hemicellulose, detergent fiber degradation (P < 0.001), total gas, methane and ammonia nitrogen (NH3-N) production. Monensin also significantly decreased acetate, butyrate, L-lactate (mmol.day-1) production and it increased propionate production (P > 0.001) and efficiency of microbial synthesis. The combined effect of nisin and monensin in V4 was similar to the effect of monensin in V3 compared to control. Then, the effect of additive monensin was dominant over nisin. In conclusion, our results indicate that nisin was less effective than monensin on some fermentation parameters (important for the improvement of the efficiency of utilization of the diet by ruminants) in artificial rumen. 相似文献
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乳酸菌以其安全、操作简单等优点被广泛用于表达外源基因,在食品、农业及医药工程领域,具有广阔的应用前景,开发了一系列乳酸菌食品级基因表达系统。目前已建立了糖诱导表达系统、噬菌体φ31暴发式诱导表达系统、乳链球菌素调控表达系统、温控表达系统等。随着基因工程技术的发展, 以重组乳酸菌作为基因工程菌的时代将要到来。 相似文献
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乳酸链球菌素治疗奶牛乳房炎效果观察 总被引：1，自引：0，他引：1
乳酸链球菌素（Nisin）是由乳酸链球菌产生的合有34个氨基酸的抗菌肽,对人体无害。本研究将患临床型乳房炎奶牛92头（107个乳区）和隐性乳房炎奶牛90头（90个乳区）随机分成试验组和对照组。试验组的治疗方法是在患病乳区灌注Nisin;临床型乳房炎以庆大霉素乳房内灌注作对照,隐性乳房炎的对照组不作任何处理。临床型乳房炎的Nisin治疗组细菌学治愈率和临床治愈率分别为60．8％和90．2％,而庆大霉素治疗组则分别为44.6％和91．2％,两者无统计学差异。隐性乳房炎经Nisin治疗后,高体细胞数奶牛的数量和牛奶中NAGase的活性均显著下降,细菌转阴率提高。乳酸菌发酵试验表明,经Nisin乳房内灌注治疗临床型乳房炎后,牛奶在第36小时恢复正常发酵,而庆大霉素治疗则需要72h。 相似文献
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Budi SANTOSO Benson MWENYA Chetra SAR Yuko GAMO Takeo KOBAYASHI Reina MORIKAWA Junichi TAKAHASHI 《Animal Science Journal》2004,75(6):525-531
A 4 × 6 Youden square design was used to study manipulating effect of Yucca schidigera with or without nisin on rumen fermentation characteristics and microbial protein synthesis in sheep fed silage‐ and hay‐based diets. Four ruminally canulated wethers were given isonitrogenous diets of timothy silage and concentrate (85:15) (S), and timothy hay and concentrate (60:40) (H), on DM basis. The six experimental diets were: (i) S; (ii) S + 240 ppm of Yucca schidigera (SY); (iii) S + 240 ppm of Yucca schidigera + 6 mg/kg bodyweight (BW)0.75 of nisin (SYN); (iv) H; (v) H + 240 ppm of Yucca schidigera (HY); and (vi) H + 240 ppm of Yucca schidigera + 6 mg/kg BW0.75 of nisin (HYN). Rumen pH was higher (P < 0.01) in sheep fed SYN diet than those fed S diet. Concentration of ammonia‐N (NH3‐N) was significantly lower (P < 0.05) in sheep fed SY, SYN, HY, HYN than those of S and H. Total volatile fatty acids concentration was significantly lower (P < 0.05) in HYN than in H diet and tended to be higher in sheep fed H diets than those fed S diets. There was a significantly higher (P < 0.01) efficiency of microbial nitrogen synthesis in the rumen of sheep fed on HY diet than those fed on H diet. 相似文献
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本试验旨在探究不同蛋白源日粮条件下添加乳酸链球菌素（nisin）对育肥湖羊瘤胃发酵及微生物菌群结构的影响。试验采用2×2因子设计,两因子分别为蛋白源[豆粕（SBM）、干玉米酒精糟及其可溶物（DDGS）]和nisin （添加水平为0或30.5 mg·kg-1 DM）,两两组合,配制4种等氮等能日粮。选取32只体重（23±2） kg的断奶湖羊公羔,按照随机区组设计,根据体重分为2个区组（低体重组,16只;高体重组,16只）,每个区组的湖羊随机分配到4个组并分别饲喂对应日粮,单栏饲喂。试验预饲期1周,正式期9周,试验期结束时每组从高、低体重区组中各随机选取3只湖羊（共24只）进行屠宰,采集瘤胃内容物,提取微生物基因组DNA,利用Illumina MiSeq测序和Real-time qPCR方法分析瘤胃微生物菌群结构。研究结果表明,除Ruminococcaceae NK4A214 group和Unclassified Bacteroidetes相对丰度外,日粮蛋白源与nisin对其他所有测定指标（瘤胃发酵参数、瘤胃菌群数量、瘤胃细菌多样性及相对丰度等）均不存在交互作用（P>0.05）。日粮添加nisin对所有测定指标均无显著影响（P>0.05）。与饲喂豆粕湖羊相比,饲喂DDGS湖羊瘤胃乙酸、氨态氮浓度及总支链脂肪酸（BCVFA）浓度显著降低（P<0.05）。qPCR结果显示,饲喂不同蛋白源日粮湖羊瘤胃总菌、真菌及甲烷菌数量均无显著差异（P≥0.053）,但相对于饲喂豆粕湖羊而言,饲喂DDGS湖羊瘤胃内原虫和嗜氨梭菌（C.aminophilum）数量显著降低（P<0.05）。Illumina-MiSeq测序结果表明,饲喂DDGS湖羊瘤胃内细菌Chao1指数和ACE指数显著升高（P<0.05）。不同日粮处理组在门水平上的优势菌门均为Bacteroidetes及Firmicutes;在属水平各处理组的主要优势菌属为Prevotella 1、Christensenellaceae R-7 group和Ruminococcaceae NK4A214 group。饲喂不同蛋白源湖羊瘤胃细菌在门水平上并未产生显著影响（P≥0.14）;在属水平上,饲喂DDGS湖羊瘤胃Pseudobutyrivibrio和Roseburia丰度均显著高于饲喂豆粕湖羊（P<0.05）,而Butyrivibrio 2以及Ruminococcaceae UCG-005的相对丰度显著低于饲喂豆粕湖羊（P<0.05）。综上所述,使用DDGS作为日粮蛋白源改变了湖羊瘤胃发酵参数及微生物菌群结构,原虫和C.aminophilum数量的降低可能是导致瘤胃氨态氮浓度显著降低的主要原因;日粮添加30.5 mg·kg-1 DM的nisin对育肥期湖羊瘤胃发酵参数及微生物菌群结构均无显著影响。 相似文献
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B. Santoso C. Sar T. Kobayashi K. Kimura J. Takahashi 《Livestock Production Science》2004,91(3):209-217
The effects of galacto-oligosaccharides (GOS), Yucca schidigera (YS) or nisin (NS), as additives to a basal diet of grass silage and concentrate, on rumen methanogenesis, nitrogen and energy metabolism were conducted using four rumen cannulated wethers in a 4×4 Latin square design. Four treatments comprised basal diet (control), basal diet+20 g GOS, basal diet+120 ppm YS, basal diet+3 mg/kg BW0.75 of NS. Apparent digestibility of DM, OM, CP, NDF and ADF were similar in all treatment diets. Animals fed YS had lower N losses in urine and total N losses resulting in a higher retained N. Ruminal pH values ranged from 6.33 to 6.47 and was significantly (P<0.05) altered by treatment. Sheep given YS had the lowest NH3-N concentration, moderate in control and GOS, and the highest in NS. The GOS supplemented sheep had lower (P<0.01) proportion of acetic acid and higher (P<0.01) proportion of propionic acid compared to those fed the control diet. Microbial nitrogen supply was higher (P<0.05) in GOS supplemented sheep than those given control, YS and NS diets. Relative to control, YS and NS treatments, GOS reduced (P<0.05) methane production (l/kg BW0.75). These results indicated that natural products have the potential to be used as manipulators of rumen fermentation. 相似文献