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为评估1株产纤维素酶的解淀粉芽孢杆菌SSY1株的安全性,本试验对其进行了急性毒性、慢性毒性、细菌易位、代谢产物及药敏等安全性试验。急性毒性试验分为高剂量组（1.30×1010 CFU/mL）、中剂量组（0.90×1010 CFU/mL）、低剂量组（0.65×1010 CFU/mL）和生理盐水对照组,一次性灌服后观察14 d,处死存活小鼠,剖检。慢性毒性试验分为高剂量组（0.65×1010 CFU/mL）、中剂量组（0.65×109 CFU/mL）、低剂量组（0.65×108 CFU/mL）和生理盐水对照组,各组灌服1次/d,连续灌服30 d。结果表明,急性毒性试验小鼠的精神、食欲、行为、粪便等均未见异常,试验鼠全部存活,剖检未见病理变化;慢性毒性试验小鼠均无异常临床变化,剖检小鼠也未见病变,高、中、低剂量组及对照组间小鼠增重、饲料利用率、血液学指标、血液生化指标及脏器系数均差异不显著（P>0.05）;解淀粉芽孢杆菌SSY1菌株在小鼠体内未发生易位,氨基脱羧酶、吲哚试验均为阴性,在测定的24种常用药物中,除林可霉素耐药外,菌株对其余23种药物均敏感。试验证实,解淀粉芽孢杆菌SSY1株的安全性良好。 相似文献
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This study was aimed to explore the effect,dose of Lactobacillus reuteri on inhibition of pathogenic Escherichia coli infection on Kunming mice as well as its potential mechanism. 96 Kunming mice were randomly allocated into four groups with 4 replicates per group and 6 mice per replicate,which were control group,low dose group,middle dose group and high dose group. All of the mice feed commercial basal feedstuff,meanwhile the mice in control group drank tap-water,three treatments were supplemented with 1.0×106,1.0×107 and 1.0×108 CFU/mL Lactobacillus reuteri in water. The feeding period was 28 days. All the mice were weighted, and the ADFI,ADG and F/G were calculated at the end of experiment.At the day of 28,pathogenic Escherichia coli (4.98×109 CFU/mL) were irrigated to study the mortality. The indexes of intestinotoxin and antioxidation in serum and cecal microbacteria were inspected.The results indicated that supplemented with middle dose of Lactobacillus reuteri could significantly improve the final body weight,ADG compared with the control (P<0.05). The mortality, serum intestinotoxin level and MDA concentration,Escherichia coli and Staphylococcus were significantly lower than control group (P<0.05),while the T-SOD,T-AOC,GSH-Px,Lacobacillus and Bifidobacterium were significantly improved (P<0.05).In conclusion,with Lactobacillus reuteri supplementation,the growth performance was improved and antioxidant capacity and cecal microbacteria were enhanced after pathogenic Escherichia coli infected, mouse mortality caused by the pathogenic Escherichia coli was effectively reduced,and the effect of 1.0×107 CFU/mL Lactobacillus reuteri was the best. 相似文献
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本研究旨在探索益生罗伊氏乳杆菌抑制致病性大肠杆菌感染昆明鼠的效果、剂量及潜在机制。将96只昆明鼠随机分为4个组,每组4个重复,每个重复6只,分别为对照组、低剂量组、中剂量组和高剂量组。昆明鼠饲喂商品化基础日粮,对照组饮用自来水,低、中、高剂量组在饮水中分别添加1.0×106、1.0×107及1.0×108 CFU/mL罗伊氏乳杆菌。试验期为28 d,试验结束后称重,计算昆明鼠平均日采食量（ADFI）、平均日增重（ADG）及料重比（F/G）;并灌胃致病性大肠杆菌（4.98×109 CFU/mL）,观察小鼠死亡率;检测血清大肠杆菌肠毒素含量、抗氧化能力及肠道菌群数量。结果显示,中剂量组小鼠末重和平均日增重均显著高于对照组（P<0.05）,小鼠死亡率、血清大肠杆菌肠毒素浓度和丙二醛（MDA）水平均显著低于对照组（P<0.05）。中剂量组血清总超氧化物歧化酶（T-SOD）、谷胱甘肽过氧化物酶（GSH-Px）和总抗氧化力（T-AOC）活力均显著高于对照组（P<0.05）,总乳杆菌和双歧杆菌数量显著提高（P<0.05）,大肠杆菌和沙门氏菌含量显著降低（P<0.05）。综上,在小鼠饮水中添加罗伊氏乳杆菌可提高生长性能,改善攻毒后机体抗氧化力和盲肠菌群结构,降低血清大肠杆菌肠毒素含量和小鼠死亡率,有效降低致病性大肠杆菌的感染造成的死亡率,其中添加1.0×107 CFU/mL伊氏乳杆菌效果最好。 相似文献
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本试验旨在研究体外感染金黄色葡萄球菌与大肠杆菌对奶牛子宫内膜组织中细胞因子白介素-6（IL-6）、IL-1β和IL-8的表达及损伤程度的影响。以体外培养的奶牛子宫内膜组织作为研究对象,采用1×105~1×109 CFU/mL大肠杆菌与金黄色葡萄球菌对奶牛子宫内膜组织进行体外感染,通过实时荧光定量PCR和ELISA方法检测两种细菌刺激后奶牛子宫内膜组织中IL-6、IL-1β及IL-8 mRNA与蛋白的表达量,并用HE染色法观察两种细菌感染后奶牛子宫内膜组织病理学切片。结果显示,1×105~1×109 CFU/mL大肠杆菌体外感染后,奶牛子宫内膜组织中IL-6、IL-1β和IL-8 mRNA表达量均极显著高于空白对照组（P<0.01）;金黄色葡萄球菌感染浓度为1×105、1×106 CFU/mL时,IL-6、IL-1β mRNA表达量极显著高于空白对照组（P<0.01）,感染浓度为1×107 CFU/mL时,IL-6、IL-1β mRNA表达量显著高于空白对照组（P<0.05）,感染浓度为1×106 CFU/mL时,IL-8 mRNA表达量显著高于空白对照组（P<0.05）,其他感染浓度均与空白对照组无显著差异（P>0.05）。奶牛子宫内膜组织感染1×105~1×109 CFU/mL金黄色葡萄球菌和大肠杆菌时,IL-6、IL-1β及IL-8蛋白表达量均极显著高于空白对照组（P<0.01）。相同浓度的大肠杆菌感染奶牛子宫内膜组织后,IL-6、IL-1β及IL-8 mRNA与蛋白表达量均极显著高于金黄色葡萄球菌感染组（P<0.01）。HE切片染色结果显示,大肠杆菌感染后仍有部分上皮细胞保留,而金黄色葡萄球菌感染后上皮细胞全部脱落。本试验结果表明,大肠杆菌与金黄色葡萄球菌感染奶牛子宫内膜组织后,引起的炎症反应不同。大肠杆菌感染后,促炎性细胞因子被显著上调,而金黄色葡萄球菌感染后破坏子宫内膜上皮细胞程度更加严重。 相似文献
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瘤胃源益生菌对小鼠生长和生理特性的影响 总被引：1，自引：0，他引：1
试验旨在对筛选出的6种瘤胃源益生菌进行小鼠试验,以期为其在畜禽养殖业的进一步开发和利用提供参考依据。选取5周龄雄性昆明小鼠56只,随机分为7组：生理盐水对照组、解淀粉芽孢杆菌Lw-J21组、枯草芽孢杆菌Lw-K16组、乳酸菌Lw-R35组、产蛋白酶菌Lw-D48组、产纤维素酶菌Lw-X21组和酵母菌Lw-JM70组,试验组每天以0.2 mL/10 g体重剂量连续灌胃42 d,对照组灌喂相同剂量的生理盐水,比较并分析灌胃不同益生菌对小鼠体重、肠道菌群数量、脂肪积累量、免疫器官指数和血糖降解能力等的影响。结果显示,与对照组相比,解淀粉芽孢杆菌Lw-J21和产纤维素酶菌Lw-X21组小鼠体重增加明显（P>0.05）,同时可显著减少小鼠体内的脂肪积累（P<0.05）。乳酸菌Lw-R35和产纤维素酶菌Lw-X21组小鼠肠道中的乳酸菌和总厌氧菌数量均显著或极显著增多（P<0.05;P<0.01）。各益生菌组小鼠脾脏指数和胸腺指数均有显著或极显著提高（P<0.05;P<0.01）,且可不同程度提高小鼠血糖的调节能力。综上所述,用筛选出的6种天然益生菌饲喂小鼠可改善其肠道微生态环境、免疫器官指数和血糖调节能力等。 相似文献
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This experiment was conducted to investigate the effects of different compound probiotics on growth performance and immune function of pigeons. 72 pairs of breeding pigeons and 144 squabs were selected and randomly divided into 4 groups with 6 replicates per group and 3 pairs of breeding pigeons and 6 young pigeons per replicate.The pigeons in all groups were fed the basal diet with health care sand,meanwhile and pigeons in groups Ⅰ, Ⅱ and Ⅲ supplemented with compound probiotics Ⅰ (6×107 CFU/g Lactobacillus acidophilus+6×107 CFU/g Bifidobacterium lactis),compound probiotics Ⅱ (6×107 CFU/g Bifidobacterium lactis+6×107 CFU/g Enterococcus faecalis) and compound probiotics Ⅲ (6×107 CFU/g Lactobacillus acidophilus+6×107 CFU/g Enterococcus faecalis),resperctively. The experiment lasted for 56 d. The results showed that compared with the control group,compound probiotics Ⅱ could significantly increase the body weight and the average daily gain of pigeon at 28 and 56 days of age (P<0.05). The thymus index of the 28 days old pigeon in group Ⅱ was significantly increased (P<0.05),and the spleen index of the 56 days old pigeon in group Ⅲ was significantly increased (P<0.05). All the compound probiotics groups could increase serum immunoglobulin content of 28 and 56 days old pigeon,but did not reach a significant level (P>0.05).In summary,compound probiotics could improve the growth performance and immune organ indexes,and improve the immunity of pigeon to a certain extent, the Bifidobacterium lactis and Enterococcus feacalis had the better effect. 相似文献
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本试验旨在研究复合益生菌对肉鸽生长性能和免疫机能的影响。选取72对种鸽和144只1日龄乳鸽,乳鸽称量初始体重后随机分成4个试验组,每个试验组6个重复,每个重复3对种鸽及6只乳鸽。各组饲喂相同基础日粮,对照组补饲保健砂,Ⅰ组补饲保健砂+复合菌Ⅰ（6×107 CFU/g嗜酸乳杆菌+6×107 CFU/g乳双歧杆菌）,Ⅱ组补饲保健砂+复合菌Ⅱ（6×107 CFU/g乳双歧杆菌+6×107 CFU/g粪肠球菌）,Ⅲ组补饲保健砂+复合菌Ⅲ（6×107 CFU/g嗜酸乳杆菌+6×107 CFU/g粪肠球菌）。试验期56 d。结果显示,与对照组相比,Ⅱ组显著提高了肉鸽的28和56日龄体重和平均日增重（P<0.05）。Ⅱ组显著提高了28日龄肉鸽的胸腺指数（P<0.05）;Ⅲ组显著提高了56日龄肉鸽的脾脏指数（P<0.05）。3个复合菌组提高了28和56日龄肉鸽血清中免疫球蛋白的含量,但均未达到显著水平（P>0.05）。综上所述,保健砂中添加复合益生菌可提高肉鸽的生长性能、免疫器官指数,并一定程度上能提高肉鸽的免疫力,其中乳双歧杆菌和粪肠球菌组效果最好。 相似文献
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为优化环介导等温扩增（loop-mediated isothermal amplification,LAMP）法检测牛奶中结核分枝杆菌的条件,以结核分枝杆菌高度保守的16S rRNA基因为靶基因设计3对特异性引物（F3-B3、FIP-BIP、FLP-BLP）进行试验。比较改良后的CATB/NaCl法、细菌基因组DNA提取试剂盒及热裂解法提取其DNA的效率,确定最佳的提取方法。用灭菌处理过的牛奶对结核分枝杆菌悬液进行倍比稀释以确定该检测方法的敏感度。以牛奶中常见的布鲁氏菌、大肠杆菌、金黄色葡萄球菌、李斯特菌、巴氏杆菌、沙门氏菌为对照,对该方法进行特异性测试。结果表明,改良后的CTAB/NaCl法对牛奶中结核分枝杆菌DNA的提取效果要优于其他两种方法。LAMP法检测结核分枝杆菌的灵敏度为3×100 CFU/mL,对人工阳性乳中结核分枝杆菌检测的灵敏度为3×101 CFU/mL。 相似文献
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YANG Min WANG Hui-dang YU Lu WU Chang-xin Zhang Hui CAO Xu-dong CHEN Chuang-fu 《中国畜牧兽医》2016,43(7):1688-1693
To optimize the loop-mediated isothermal amplification (LAMP) method to detect Mycobacterium tuberculosis in milk,the highly conservative 16S rRNA gene of Mycobacterium tuberculosis was selected as a target to design specific primers.Compared the modified method of CATB/NaCl,bacterial genome DNA extraction kit and thermal cracking method to extract the DNA of Mycobacterium tuberculosis,the best approach was chosen.Mycobacterium tuberculosis suspension liquid was diluted with sterilization milk to confirm the susceptibility of this assay.And then Brucella,Escherichia coli,Staphylococcus aureus,Listeria monocytogenes,Bacillus pasteurii and Salmonella were used for specificity detection.The results showed that the modified method of CATB/NaCl was better than the others.The sensitivity of LAMP was 3×100 CFU/mL,and the specificity was 100%.The sensitivity of detecting Mycobacterium tuberculosis in milk by LAMP was 3×101 CFU/mL. 相似文献
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试验旨在研究大肠杆菌（E.coli）对奶牛子宫内膜上皮细胞（bovine endometrial epithelial cells,BEECs）的体外炎性损伤,探究大肠杆菌引发炎性反应的最佳浓度、作用时间及机制。首先,用不同浓度的大肠杆菌（5×104、5×105、1×106、2.5×106、5×106 CFU/mL）诱导刺激细胞3、6和9 h,通过倒置显微镜观察细胞形态、CCK-8法测D450 nm值,检测大肠杆菌对细胞活性的影响;其次,用不同浓度的大肠杆菌（5×104、5×105 CFU/mL）处理细胞3、6和9 h,用ELISA方法检测细胞上清液中白介素-1β（IL-1β）、IL-6、IL-8和肿瘤坏死因子-α（TNF-α）的分泌量;最后,用不同浓度的大肠杆菌（5×104、5×105 CFU/mL）处理细胞6和9 h,用Western blotting检测核因子κB抑制蛋白α（IκBα）和p65蛋白的磷酸化水平。结果显示,与对照组相比,大肠杆菌感染细胞9 h后,1×106、2.5×106和5×106 CFU/mL大肠杆菌组细胞活性均极显著降低（P<0.01）,5×105 CFU/mL大肠杆菌组显著降低（P<0.05）;大肠杆菌感染细胞9 h后,5×105 CFU/mL大肠杆菌组IL-1β、IL-6、IL-8和TNF-α极显著升高（P<0.01）;大肠杆菌感染细胞6 h后,5×105 CFU/mL大肠杆菌组IκBα、p65蛋白磷酸化水平和IL-6均极显著升高（P<0.01）,5×104 CFU/mL大肠杆菌组IκBα和p65蛋白磷酸化水平显著升高（P<0.05）。结果表明,大肠杆菌可以刺激奶牛子宫内膜上皮细胞产生炎性反应,且当细胞与5×105 CFU/mL大肠杆菌作用6 h或与5×104 CFU/mL大肠杆菌作用9 h为最佳。 相似文献
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The purpose of the experiment was to establish a rapid multiplex PCR detection method which could distinguish B.abortus，B.melitensis，B.suis and B.canis. According to the differences of IS711 and complete genome sequences，four pairs of primers were designed. Multiplex PCR reaction system and conditions were optimized，the specificity，sensitivity and stability of the multiplex PCR were analyzed.Through the establishment of the multiplex PCR，B.abortus，B. melitensis，B. suis and B.canis could amplify the expected fragment，the sizes of the expected fragment were 494，732，591 and 272 bp，respectively. The PCR sensitivity of B.abortus，B.melitensis，B.suis and B.canis were 1.1×102，5.1×102，3.5×102 and 2.5×102 CFU/mL，respectively. Detected artificially infectious samples of milk by PCR，PCR sensitivity could reach 1.0×103 CFU/mL.The developed multiplex PCR method was simple，fast，high sensitivity，and had good prospects and important significance for the identification of B.abortus，B.melitensis，B.suis and B.canis. 相似文献
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为探究辽宁省西丰县鹿场环境中细菌的分布及耐药性情况,本试验采集了鹿场粪便、饮水、空气、饲料等样品,进行了细菌的分离培养及鉴定,对分离到的菌株16S rDNA基因进行PCR扩增、测序分析,并对分选出的致病菌和条件致病菌进行药敏试验。结果显示,所测样品共分离纯化出27株菌,公鹿精饲料、母鹿精饲料、粗饲料和水的含菌量分别为1.0×105、8.7×104、2.7×107 CFU/g和2.9×104 CFU/mL,表明水和粗饲料不符合国家规定的养殖场环境卫生要求;16S rDNA基因序列在NCBI比对后,鉴定出有大肠埃希菌、志贺氏菌等15种不同菌株,其中致病菌和条件致病菌共13种,这13种细菌对呋喃唑酮、多黏菌素B和头孢氨苄等耐药,对头孢曲松、环丙沙星和丁胺卡那等药物敏感。本试验结果可为鹿场细菌性疾病的防控及用药提供参考依据。 相似文献
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ZHANG Ting LIU Han-lu XING Jing-ya SI Hua-zhe ZHONG Wei YUE Zhi-gang LI Guang-yu 《中国畜牧兽医》2017,44(1):94-99
This experiment was conducted to study the effects of Lactobacillus probiotics on growth performance,nutrient digestibility and serum biochemical indexes in arctic foxes during the winter fur-growing period. Forty 135-day-old female arctic foxes with a similar body weight were randomly divided into 4 groups with 10 replicates per group and 1 fox per replicate. The foxes in control group were fed basal diets,while that of groups Ⅱ,Ⅲ and Ⅳ were fed basal diet+0.02% colistin sulfate, basal diet+1 mL Lactobacillus probiotics (active Lactobacillus was 3×109 CFU/mL) and basal diet+10 mL Lactobacillus probiotics,respectively. The results showed that:Compared to the control group,the addition of Lactobacillus probiotics significantly increased the average daily gain (P<0.05) and significantly decreased the F/G of arctic foxes during the winter fur-growing period (P<0.05).The apparent digestibility of EE and GE were significantly increased when arctic foxes fed diet supplemented with Lactobacillus probiotics (P<0.05).Supplementation of high level Lactobacillus probiotics could significantly decrease serum total cholesterol (P<0.05). Additionally,serum alanine aminotransferase concentration of group Ⅱ was extremely significantly higher than that of the other three treatments (P<0.01). Moreover,the serum aspartate aminotransferase concentration was significantly higher than the control group (P<0.05). In conclusion,the addition of Lactobacillus probiotics had beneficial effects on growth performance and apparent digestibility of EE and GE when arctic foxes got 3×109 CFU/mL active Lactobacillus from the probiotics per day. The total cholesterol in serum was significantly decreased when arctic foxes get 3×1010 CFU/mL active Lactobacillus from the probiotics per day. It might cause the liver damage when arctic fox got colistin sulfate for a long time. 相似文献
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试验旨在研究乳酸菌微生态制剂对冬毛期北极狐生长性能、营养物质消化率及血清生化指标的影响。选取135日龄、体重相近的健康雌性北极狐40只,随机分为4组,每组10个重复,每个重复1只。Ⅰ组饲喂基础日粮;Ⅱ组饲喂基础日粮+0.02%硫酸黏杆菌素;Ⅲ组饲喂基础日粮+1 mL乳酸菌微生态制剂（乳酸菌活菌数为3×109 CFU/mL）;Ⅳ组饲喂基础日粮+10 mL乳酸菌微生态制剂。结果显示：与对照组相比,添加乳酸菌微生态制剂可显著提高冬毛期北极狐平均日增重（P<0.05）,并显著降低料重比（P<0.05）;可显著提高冬毛期北极狐粗脂肪和总能表观消化率（P<0.05）;添加高水平乳酸菌微生态制剂可显著降低冬毛期北极狐血清总胆固醇水平（P<0.05）。此外,抗生素组北极狐血清谷丙转氨酶水平极显著高于其他各组（P<0.01）,谷草转氨酶水平显著高于对照组（P<0.05）。综上所述,在本试验条件下,当北极狐日采食活乳酸菌数达到3×109 CFU/mL时即可促进其生长,粗脂肪和总能表观消化率显著提高;当北极狐日采食活乳酸菌数达到3×1010 CFU/mL时,血清总胆固醇水平显著降低;长期添加硫酸黏杆菌素可能造成北极狐肝脏损伤。 相似文献
18.
试验旨在研究补饲复合微生态制剂对泌乳期伊犁母马血液生化指标及抗氧化能力的影响.根据年龄、胎次、泌乳月龄相近的原则选择泌乳期伊犁母马24匹,随机分为4组,分别为对照组、试验Ⅰ组、试验Ⅱ组和试验Ⅲ组.对照组饲喂基础日粮,试验Ⅰ、Ⅱ、Ⅲ组在饲喂基础日粮的基础上分别补饲0.05 g枯草芽孢杆菌(活菌数为2.0×1011 CFU/g)和0.133 g植物乳杆菌(活菌数为3.0×1010 CFU/g)、0.10 g枯草芽孢杆菌和0.266 g植物乳杆菌、0.15 g枯草芽孢杆菌和0.399 g植物乳杆菌.结果表明,与对照组相比,补饲复合微生态制剂对泌乳期伊犁母马血液中总蛋白、白蛋白、血尿素氮含量和谷胱甘肽过氧化物酶、超氧化物歧化酶活性的影响均差异不显著(P> 0.05);但补饲复合微生态制剂泌乳期伊犁母马血液中总蛋白、白蛋白含量和超氧化物歧化酶活性呈升高的趋势;试验Ⅱ组泌乳期伊犁母马血液中球蛋白含量显著高于对照组和试验Ⅰ组(P <0.05),其他各组之间差异不显著(P> 0.05).过氧化氢酶的活性试验Ⅱ组显著高于对照组和试验Ⅲ组(P <0.05),试验Ⅰ组与其他各组之间差异不显著(P> 0.05);总抗氧化能力试验Ⅱ组显著高于试验Ⅰ和Ⅲ组(P <0.05),其他各组之间差异不显著(P> 0.05).因此,补饲植物乳杆菌和枯草芽孢杆菌复合物对泌乳期母马增强免疫机能,改善氮沉积,提高机体抗氧化能力起到了一定作用,且补饲0.10 g枯草芽孢杆菌和0.266 g植物乳杆菌复合物时效果较为明显. 相似文献
19.
试验旨在筛选一株地衣芽孢杆菌M109(Bacillus licheniformis M109)进行培养基和发酵条件的优化。采用单因素试验方法筛选出最佳碳源和氮源的培养基,并利用正交试验方法确定其最佳的碳氮比。为了继续提高地衣芽孢杆菌M109的发酵水平,研究其在发酵过程中的生长曲线、pH和溶氧(DO)水平的变化曲线,通过对发酵过程中生长参数的测定,优化了地衣芽孢杆菌M109最佳的接种量和最适pH。结果发现,溶氧限制是地衣芽孢杆菌M109生长的关键因素;在限定通风量的条件下,通过调节搅拌转速的方法来提高培养基中的溶氧水平,提高发酵密度;通过流加培养基的方法也能提高地衣芽孢杆菌M109的发酵水平。因此,通过对培养基和发酵条件的优化,使地衣芽孢杆菌M109的发酵水平由最初的1.0×109 CFU/mL提高到1.2×1010 CFU/mL,芽孢形成率为88%。 相似文献
20.
单核细胞增生性李斯特菌(Listeria monocytogenes,LM)是一种人畜共患食源性致病菌,能引起人和动物较为严重的感染症状。现广泛使用具有免疫活性的小鼠模型测定半数致死量(LD50)来评价不同LM菌株的致病性。为建立LM的ICR小鼠模型,本研究采用1/2a血清型的N21 LM菌株,分别以106、107、108、109和1010 CFU的剂量口腔灌注感染6周龄ICR小鼠,每组10只;另取10只接种PBS作为对照组,测定LM对ICR小鼠的LD50;另取40只小鼠,平均分为2组,公母各半,以测定的LD50剂量接种LM,分别对各组小鼠临床症状、组织病理变化、体重变化及组织中细菌载量进行评价。结果发现,N21 LM菌株对ICR小鼠的LD50为109.25 CFU;感染周期为10 d左右,感染小鼠出现被毛粗糙、精神萎靡、阴茎垂出及体重下降等临床症状。组织病理学分析结果显示,肝脏先后出现实质内灶状细菌团块、形成血栓、细胞坏死等;脾脏主要表现为白髓内淋巴细胞减少;肺脏主要表现为纤维素性肺炎。菌落计数和Real-time PCR的检测结果发现肝脏中细菌载量最高,脾脏次之。结果表明,ICR小鼠能作为单核细胞增生性李斯特菌的感染模型。本试验结果为研究LM的致病机制、疫苗研究及抗菌肽转基因小鼠抗LM的评价奠定了基础。 相似文献