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1.
[目的]分离、鉴定新疆维吾尔自治区呼图壁县驼乳源乳酸菌,评价其对金黄色葡萄球菌的抑制作用。[方法]从呼图壁县某驼场采集健康驼乳样本45份,使用MRS培养基分离乳酸菌,采用细菌16S rDNA序列PCR扩增及测序方法进行分子生物学鉴定。利用点种法、琼脂斑点法和牛津杯双层琼脂扩散法筛选对金黄色葡萄球菌ATCC 29213具有抑制作用的乳酸菌。将MRS培养基的pH值调节至1~10,测定乳酸菌的耐酸能力;在MRS培养基中添加0~0.30%的牛胆盐,测定乳酸菌的耐胆盐能力。应用微量肉汤倍比稀释法测定乳酸菌无细胞上清液(cell-free culture supernatant,CFCS)对金黄色葡萄球菌ATCC 29213的最低抑菌浓度(minimum inhibitory concentration,MIC)和亚抑菌浓度(subinhibitory concentration,SIC);考查CFCS在不同pH值条件下及经酶处理后对金黄色葡萄球菌ATCC 29213的抑制作用变化,初步分析CFCS的抑菌活性物质;利用牛津杯双层琼脂扩散法测定CFCS对驼乳源和奶牛乳房炎源金黄色葡萄球菌野生株的抑制...  相似文献   

2.
探讨柴胡皂苷a对金黄色葡萄球菌的抑菌活性,确定亚抑菌浓度的柴胡皂苷a对金黄色葡萄球菌基因转录表达谱的影响。按NCCLS推荐的试管肉汤倍比稀释法测定柴胡皂苷a对32株临床分离的金黄色葡萄球菌和标准菌株ATCC25923的最小抑菌浓度(MICs),绘制标准菌株ATCC25923的生长曲线,用定制的Affymetrix基因芯片检测1/2×MIC(4mg.L-1)柴胡皂苷a对标准菌株ATCC25923基因表达谱的影响。结果表明,柴胡皂苷a对33株金黄色葡萄球菌的MICs为1~32mg.L-1;基因表达谱分析有26个上调基因,68个下调基因,其中1个编码超氧负离子压力反应蛋白基因被大幅度地上调,13个毒力基因被诱导,并且都被抑制;这表明柴胡皂苷a对32株临床分离的金黄色葡萄球菌及标准菌株都有抑菌活性。基因芯片分析表明,柴胡皂苷a的抗菌作用能够同时影响金黄色葡萄球菌不同的途径基因。  相似文献   

3.
研究考察了茅膏菜水提物和醇提物体外抑菌活性和体外抗氧化活性。对茅膏菜水提物及醇提物采用管碟法测试抑菌效果和Fenton法清除羟自由基(-OH)的清除率。结果表明:茅膏菜水提物及醇提物对沙门氏菌、大肠杆菌和金黄色葡萄球菌生长均有较强的抑制作用;茅膏菜醇提物的抑制效果更为显著;茅膏菜水提物对沙门氏菌、大肠杆菌的最低抑菌浓度(MIC)与最低杀菌浓度(MBC)值相等,为62.50 mg/mL;对金黄色葡萄球菌的MIC与MBC也相同,为125.00 mg/mL;醇提物对沙门氏菌、大肠杆菌的MIC与MBC值相等,为31.25 mg/mL;对金黄色葡萄球菌的MIC与MBC也相同,为15.63 mg/mL。茅膏菜水提物及醇提物对羟自由基有较强的清除作用,其效果随浓度的增加而提高。由此可见,茅膏菜水提物和醇提物有较好的体外抑菌活性和抗氧化活性。  相似文献   

4.
本文针对甘草、黄连、板蓝根、黄芩、黄芪、大青叶6种中药醇和水提取物,研究其对金黄色葡萄球菌和大肠杆菌的抗菌作用效果。采用醇提法和水提法获得6种中药醇和水提取物;通过药敏试验,筛选对金黄色葡萄球菌和大肠杆菌有抑菌效果的中药提取物;通过试管2倍稀释法探明该中药提取物对金黄色葡萄球菌或大肠杆菌的最低抑菌浓度(MIC);进而探明该中药提取物对金黄色葡萄球菌或大肠杆菌的最低杀菌浓度(MBC)。结果表明,6种中药醇水提取物中仅黄连醇提物和水提物对金黄色葡萄球菌表现较强的抑菌效果,浓度在0.5 mg/mL时,黄连醇提物和水提物对金黄色葡萄球菌分别达高敏和极敏。黄连醇提物和水提物对金黄色葡萄球菌的MIC分别为0.08 mg/mL和0.04 mg/mL,MBC结果显示,黄连醇和水提取物对金黄色葡萄球菌均表现杀菌作用,MBC分别为0.16 mg/mL和0.08 mg/mL。表明黄连醇提物和水提物对金黄色葡萄球菌具有抑制作用,且黄连水提物的抑菌效果优于黄连醇提物。  相似文献   

5.
检测桃金娘不同部位水提物及醇提物对大肠杆菌、沙门菌和金黄色葡萄球菌的抑菌作用。采用琼脂扩散药敏法测定抑菌圈直径,微量倍比稀释法测定最小抑菌浓度(MIC)。结果显示,桃金娘叶、果的醇提液和水提液对金黄色葡萄球菌和沙门菌均有一定的抑菌效果,并且醇提液效果优于水提液,其中桃金娘叶醇提液的抑菌效果最好,对金黄色葡萄球菌和沙门菌的MIC分别为0.125 g/mL、0.25 g/mL。桃金娘叶、果的醇提液和水提液对大肠杆菌均无抑菌效果。  相似文献   

6.
研究鱼腥草水提物对金黄色葡萄球菌生物被膜的干预作用。采用微量肉汤稀释法测定鱼腥草水提物对金黄色葡萄球菌CMCC(B)26003的最低抑菌浓度;采用结晶紫染色法、扫描电镜及激光共聚焦显微镜评估鱼腥草水提物对CMCC(B)26003生物被膜形成的影响;最后采用实时荧光定量PCR方法测定鱼腥草水提物对O-乙酰丝氨酸硫化氢裂解酶B(O-acetylserine sulfhydrylase-B)cysM基因转录的影响。结果显示,鱼腥草水提物在12.500 mg/mL、6.250 mg/mL、3.125 mg/mL质量浓度下均可以有效抑制金黄色葡萄球菌生物被膜的形成,在12.500 mg/mL质量浓度下可下调cysM基因的表达。鱼腥草可能通过下调cysM基因的表达而抑制金黄色葡萄球菌生物被膜的形成。  相似文献   

7.
本研究旨在分析土木香提取物对金黄色葡萄球菌主要毒力因子分泌的影响及机制研究,以耐药性金黄色葡萄球菌USA 300为研究对象,通过醇提法获取土木香提取物,根据主要毒力因子蛋白表型功能(溶血活性和TNF-α含量释放分析),利用蛋白免疫印迹和荧光定量PCR分析检测不同浓度土木香提取物对金黄色葡萄球菌主要毒力因子分泌的影响及机制。无抗菌活性的土木香提取物与金黄色葡萄球菌共培养后可显著抑制培养物上清溶血活性及其诱导小鼠脾淋巴细胞TNF-α释放活性,蛋白免疫印迹分析表明,土木香提取物处理可显著降低金黄色葡萄球菌α-溶血素、肠毒素A和中毒休克综合征毒素-1(TSST-1)的分泌,荧光定量PCR试验结果进一步表明土木香提取物与金黄色葡萄球菌共培养后降低金黄色葡萄球菌α-溶血素、肠毒素A和TSST-1编码基因的转录及金黄色葡萄球菌二元调控系统agr的转录。本研究结果表明,土木香提取物通过抑制agr二元调控系统转录及其毒力因子编码基因的转录而降低毒力因子的分泌,土木香提取物是一种潜在的新型抗金黄色葡萄球菌感染先导化合物。  相似文献   

8.
为评价石榴皮水提物与抗菌药物体外联合抗菌作用的效果,试验采用双层打孔法检测石榴皮水提物的抑菌能力,采用微量二倍稀释法测定石榴皮水提物的最小抑菌浓度(MIC),使用棋盘法测定石榴皮提取物与庆大霉素、阿米卡星、链霉素、多西环素和恩诺沙星联用对金黄色葡萄球菌和大肠杆菌的作用效果。结果表明:制备的石榴皮水提物具有抑菌效果;对金黄色葡萄球菌和大肠杆菌的MIC分别为1.25 mg/mL和5 mg/mL;石榴皮水提物联合阿米卡星对大肠杆菌表现为相加作用,联合链霉素对大肠杆菌和金黄色葡萄球菌均表现为相加作用,联合庆大霉素对大肠杆菌表现为颉颃作用。说明石榴皮水提物可以与阿米卡星和链霉素联用,均表现为相加作用。  相似文献   

9.
为了研究鱼腥草素钠对金黄色葡萄球菌(S.aureus)生物被膜的抑制活性,试验采用微量稀释法考察了鱼腥草素钠对S.aureus浮游菌的最小抑菌浓度(MIC)和最小杀菌浓度(MBC),用琼脂平板法测定了其对生物被膜的最小抑膜浓度(MBIC)和最小杀膜浓度(MBBC);通过激光共聚焦显微镜考察了鱼腥草素钠对生物被膜的清除能力;通过Western-blot考察了鱼腥草素钠对S.aureus毒力因子分泌的影响。结果表明:鱼腥草素钠对浮游菌有很好的抑制作用(MIC、MBC:16~64μg/mL),对成熟的生物被膜没有明显的抑制作用(MBIC、MBBC1 024μg/mL),但其亚抑菌浓度在生物被膜形成早期有显著抑制作用,并呈剂量依赖抑制α-溶血素、肠毒素A和肠毒素B的分泌。说明鱼腥草素钠对金黄色葡萄球菌浮游菌和早期生物被膜有较好抑制活性。  相似文献   

10.
为了研究氟苯尼考纳米凝胶对新疆南疆地区乳源金黄色葡萄球菌的抑菌效果,试验从新疆南疆地区某奶牛场的乳房炎患病奶牛乳样中分离纯化金黄色葡萄球菌,采用生化试验、PCR扩增及测序等方法进行细菌鉴定,并通过比较氟苯尼考原料药、氟苯尼考纳米凝胶和氟苯尼考注射液对金黄色葡萄球菌分离株的抑菌圈直径(DIZ)、最小抑菌浓度(MIC)和抑菌曲线分析氟苯尼考纳米凝胶对金黄色葡萄球菌分离株的抑菌效果。结果表明:从乳样中分离到一株细菌,该分离株革兰氏染色、镜检后呈蓝紫色并排列成葡萄串状,触酶、血浆凝固酶和甘露醇发酵试验结果均为阳性,其基因组DNA中能扩增出金黄色葡萄球菌耐热核酸酶(nuc)基因,16S rDNA基因序列与金黄色葡萄球菌的相似性为99.7%,判断该分离菌为金黄色葡萄球菌。氟苯尼考原料药、氟苯尼考纳米凝胶和氟苯尼考注射液对金黄色葡萄球菌分离株和金黄色葡萄球菌ATCC 29213株均产生抑菌作用,DIZ大小为氟苯尼考纳米凝胶>氟苯尼考注射液>氟苯尼考原料药,均表现为高度敏感,其中氟苯尼考纳米凝胶对金黄色葡萄球菌分离株和金黄色葡萄球菌ATCC 29213株的DIZ均显著高于氟苯尼考原料药和氟...  相似文献   

11.
本试验旨在研究不同中药与盐酸恩诺沙星联用对大肠杆菌耐药菌株的体外抑菌作用。采用微量肉汤法测定临床上一种常用药物盐酸恩诺沙星和不同中药对大肠杆菌耐药菌株及其联合使用的最小抑菌浓度(minimum inhibitory concentration,MIC)。结果发现,单味中药水提物中侧柏叶、金樱子和五味子的抑菌效果较好,其MIC值分别为3.91、3.91和7.81 mg/mL;单味中药的醇提物中,侧柏叶、马齿苋抑菌效果较好,其MIC值分别为7.81和3.91 mg/mL。盐酸恩诺沙星分别与五味子和金樱子水提物联合作用后,对大肠杆菌耐药菌株的MIC值分别降低到0.0078和0.0039 mg/mL;与马齿苋、赤芍、侧柏叶和金樱子的醇提物联合后,对大肠杆菌耐药菌株MIC值均明显降低。盐酸恩诺沙星分别与鱼腥草水提物、赤芍水提物、椿皮水提物、马齿苋醇提物、苍术醇提物、三颗针醇提物、赤芍醇提物、薤白醇提物、拳参醇提物、侧柏叶醇提物、金樱子醇提物和败酱草醇提物联合作用后,对大肠耐药菌株呈现相加或协同抑菌作用,其FIC值分别为0.75、0.62、0.62、0.27、0.75、0.75、0.31、0.62、0.50、0.53、0.28和0.62。初步认为不同中药中含有能有效降低大肠杆菌耐药性的中药,也含有与盐酸恩诺沙星组合,具有协同或相加作用的中药,为寻找有效防治大肠杆菌病的药物组合来对抗多重耐药菌提供了可能。  相似文献   

12.
为了探究赤芍水提物与抗菌药联合对耐药大肠杆菌的体外抑菌作用,采用微量肉汤稀释法与微量棋盘法来测定各抗菌药与赤芍水提物的最低抑菌浓度(MIC)及二者联合作用后的分级抑菌浓度指数(FICI)。结果显示赤芍水提物与头孢曲松钠、阿莫西林、环丙沙星、诺氟沙星、左旋氧氟沙星、磷霉素、痢菌净、克林沙星、磺胺间甲氧嘧啶、加替沙星、阿米卡星、头孢他啶、林可霉素、头孢噻呋钠、氟苯尼考、阿奇霉素、头孢噻肟、利福平联合作用后的FICI分别为0.27、2.50、1.02、1.01、3.00、0.28、1.02、1.02、1.02、2.02、1.02、0.75、0.56、0.75、0.50、3.00、0.75、0.38。结果表明赤芍水提物与头孢曲松钠、磷霉素、氟苯尼考、利福平联合作用时有协同作用;与林可霉素、头孢噻呋钠、头孢噻肟、头孢他啶联合作用时有相加作用;与阿莫西林、左旋氧氟沙星、加替沙星、阿奇霉素联合作用时有颉颃作用;与环丙沙星、诺氟沙星、痢菌净、克林沙星、磺胺间甲氧嘧啶、阿米卡星联合作用时表现为无关作用。  相似文献   

13.
A total of 41 isolates of Staphylococcus aureus obtained from bovine mastitis in 7 different states in Mexico were analyzed by the polymerase chain reaction (PCR) to determine the presence of encoding genes for enterotoxins A, B and C. The oligonucleotides were designed by specific regions of the sea, seb, sec genes. Surprisingly, none of the isolates presented the prospective amplification bands when they were run on agarose gels. On the contrary, reference strains CECT 976 SEA; CECT 5191 SEB; and CECT 4465 SEC showed the prospective amplification products. In order to confirm these results, enterotoxin production A, B, C, D, and E was determined by enzyme linked fluorescent assay (ELFA) using a MiniVIDAS system, on 15 Staphylococcus aureus selected at random from among the 41 isolates. None of the analyzed strains was positive to the test, whereas reference strains enterotoxins producing: CECT 976 SEA; CECT 5191 SEB; CECT 4465 SEC, CECT 4466 SED; CECT 5192 SEE produced concentrations of the toxins detected for this technique. The role of enterotoxins in the pathogenicity of S. aureus in bovine mastitis in Mexico is discussed.  相似文献   

14.
试验根据中兽医治疗奶牛乳房炎的辨证施治原则,筛选出抑制引起奶牛乳房炎主要病原菌(金黄色葡萄球菌和大肠杆菌)的最佳中药组方,为其临床防治提供新的途径与方法。选用蒲公英、马齿苋、金银花、紫花地丁、赤芍、白芍、菊花、黄芩、漏芦、红花10味中药,通过L12(211)正交试验初步筛选抗菌中药组方中的最佳优选因素,再通过L16(45)正交试验进一步筛选药物组方配比;采用牛津杯法测定中药组方对奶牛乳房炎主要致病菌的体外抑菌效果;采用二倍稀释法和平板计数法分别测定中药组方对奶牛乳房炎主要致病菌最小抑菌浓度(MIC)和最小杀菌浓度(MBC)。结果显示,通过L12(211)正交试验初步筛选出了抗菌中药组方最佳优选因素:赤芍、黄芩、红花、菊花和白芍;L16(45)正交试验进一步筛选药物组方最佳配比为黄芩:赤芍:菊花:白芍:红花=3:3:3:1:2;新药组方对大肠杆菌的抑菌直径为17.39 mm,MIC和MBC分别为62.50、125.00 mg/mL,对金黄色葡萄球菌的抑菌直径为25.44 mm,MIC和MBC均为31.25 mg/mL。本研究成功筛选出了一种对奶牛乳房炎主要致病菌具有良好抑菌、杀菌作用的中药新配比组方。  相似文献   

15.
金银花等5种中药对猪源大肠杆菌抗菌活性的影响   总被引:1,自引:0,他引:1  
为观察金银花、五味子、黄连、赤芍、鱼腥草对猪源大肠杆菌体外抑菌效果,测定其最小抑菌浓度,本实验采用平皿打孔法测定各中草药的抑菌圈直径,梯度稀释法测定各中草药抑制病原菌生长的最小抑菌浓度,结果表明,金银花、五味子、黄连、赤芍、鱼腥草对猪源大肠杆菌的抑菌圈直径分别为23.6、20.2、22.1、15.3、17.1 mm,最小抑菌浓度分别为0.2、0.3、0.2、0.6、0.5 g/mL,金银花、五味子、黄连、赤芍、鱼腥草对猪源大肠杆菌体均有体外抑菌效果,其中金银花,黄连,五倍子的抑菌效果最好,赤芍和鱼腥草抑菌效果不明显。  相似文献   

16.
One hundred and sixty-six Staphylococcus aureus isolates from mastitic milk samples from different cows on 26 farms were investigated for staphylococcal enterotoxins(SEs) and toxic shock syndrome toxin-1(TSST-1) by polymerase chain reaction(PCR) and reverse passive latex agglutination assay(RPLA). SEs and the TSST-1 gene were detected in thirty-seven isolates based on a multiplex PCR; SEA was detected in 32 isolates, SEB in 3 isolates, SEC in 1 isolate, and SEA and the TSST-1 gene in 1 isolate. Of the 37 enterotoxigenic isolates, thirty-three isolates were enterotoxigenic according to RPLA, where 29 isolates produced SEA, 3 isolates produced SEB, and 1 isolate produced SEC. The enterotoxin-producing S. aureus isolates were further characterized by pulsed-field gel electrophoresis(PFGE). A macrorestriction analysis revealed 11 PFGE patterns. Among the 33 enterotoxigenic S. aureus isolates, 45.4% exhibited the same PFGE pattern I. Accordingly, although the enterotoxin-producing S. aureus isolates from bovine mastitis were genetically diverse, 1 common genotype prevailed on the farms, indicating that PFGE pattern I isolates may be the most disseminated in Korea.  相似文献   

17.
To observe the antiviral action of 16 kinds of Chinese medicinal herbs (Houttuynia cordata Thunb,Flos Chrysanthemi,Flos Lonicerae Confusae,Anemarrhena asphodeloides,CassiaTwig,Herba Ephedrae,Radix Paeoniae Rubra,Bupleurum chinense,Dryopteris setosa,Folium Isatidis, Gardenia jasminoides Ellis,Mntha haplocalyx Briq,Paeonia suffruticosa Andr,Cornu Bubali, Herba Senecionis Scandentis,Radix Gentianae) against porcine reproductive and respiratory syndrome virus (PRRSV), the blocking, inhibiting and killing roles were detected in present study in vitro. The results showed that 13 kinds of Chinese medicinal herbs had antiviral actions against PPRSV except Paeonia suffruticosa Andr, Herba Senecionis Scandentis and Folium Isatidis, and Houttuynia cordata Thunb, Flos Chrysanthemi, Anemarrhena asphodeloides, CassiaTwig and Radix Paeoniae Rubra exhibited the best antiviral actions followed by Herba Ephedrae, Bupleurum chinense and Dryopteris setosa.  相似文献   

18.
Milk is considered a nutritious food because it contains several important nutrients including proteins and vitamins. Conversely, it can be a vehicle for several pathogenic bacteria such as Staphylococcus aureus. This study aimed to analyze the frequency of genes encoding the staphylococcal enterotoxins (SEs) SEA, SEB, SEC, SED, SEE, SEG, SEH, SEI and SEJ in S. aureus strains isolated from raw or pasteurized bovine milk. S. aureus was found in 38 (70.4%) out of 54 raw milk samples at concentrations of up to 8.9 x 10(5) CFU/ml. This microorganism was present in eight samples of pasteurized milk before the expiration date and in 11 samples analyzed on the expiration date. Of the 57 strains studied, 68.4% were positive for one or more genes encoding the enterotoxins, and 12 different genotypes were identified. The gene coding for enterotoxin A, sea, was the most frequent (16 strains, 41%), followed by sec (8 strains, 20.5%), sed (5 strains, 12.8%), seb (3 strains, 7.7%) and see (2 strains, 5.1%). Among the genes encoding the other enterotoxins, seg was the most frequently observed (11 strains, 28.2%), followed by sei (10 strains) and seh and sej (3 strains each). With the recent identification of new SEs, the perceived frequency of enterotoxigenic strains has increased, suggesting that the pathogenic potential of staphylococci may be higher than previously thought; however, further studies are required to assess the expression of these new SEs by S. aureus, and their impact in foodborne disease. The quality of Brazilian milk is still low, and efforts from the government and the entire productive chain are required to attain consumer safety.  相似文献   

19.
Enterotoxigenic Staphylococcus aureus in raw milk poses a potential health hazard to consumers, and the identification of such strains should be used as part of a risk analysis of milk and milk products. The primary purpose of this study was to investigate the occurrence of enterotoxigenic S. aureus strains in raw milk supplied for dairy processing in the Czech Republic. A further aim was to compare the production of staphylococcal enterotoxins (SEs) with the presence of the corresponding genes. This was undertaken using multiplex polymerase chain reaction (PCR) and reversed passive latex agglutination (RPLA). Out of 440 bulk tank milk samples from 298 dairy herds, 70 proved positive for S. aureus (15.9%). Staphylococcal enterotoxin genes (ses) were detected in 39 (55.7%) isolates. The genes most commonly detected were sei (38.6%), seg (31.4%) and sea (27.1%). Genes seb, seh, sed, sej and sec were observed in 10%, 4.3%, 2.9%, 2.9% and 1.4% of strains respectively. Genes see and sel did not occur. The most frequently detected genotypes were seg, sei at 11.4%; sea at 10.0%; and sea, seg, sei at 8.6%. Toxin production was observed in nine (12.9%) S. aureus isolates. Seven strains were detected as SEB- (10%) and two as SED- (2.9%) producing. A relatively high number (32%) of discrepancies between the results with multiplex PCR and RPLA assays was obtained, particularly on account of SEA. Nineteen strains were sea positive by PCR but SEA negative by RPLA, and one strain was sec positive and SEC negative. The results of both methods were identical concerning SEB and SED. It was concluded that detection of ses by PCR was a useful additional tool to support identification of enterotoxigenic strains.  相似文献   

20.
Food poisoning by Staphylococcus aureus affects hundreds of thousands of people each year. Staphylococcus aureus also causes invasive diseases such as arthritis (in poultry) and septicemia (in poultry and humans). Foodborne disease is caused by the ingestion of a staphylococcal enterotoxin (SE). Enterotoxin has also been associated with other S. aureus illnesses in humans and domestic animals. In this study, polymerase chain reaction was used to detect the staphylococcal enterotoxin genes, SEA, SEB, SEC, SED, and SEE, in S. aureus isolates associated with invasive disease in poultry and humans. In the 34 poultry isolates, only one isolate was found to contain a SE gene, sec. In the 41 human isolates, over 51% tested positive for an SE gene with 12.2% positive for the gene for SEA, 2.4% for SEB, 22% for SEC, 24.4% for SED, and 0 for SEE. The disparity between the rates for SE gene(s) in poultry and human isolates suggests a lesser role for the enterotoxins in invasive poultry disease than in human disease.  相似文献   

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