黄连解毒汤体外抗菌活性研究

目的探讨黄连解毒汤体外抗菌活性。方法采用连续倍比试管稀释法和琼脂扩散法测定黄连解毒汤的最低抑菌浓度（MIC）和最低杀菌浓度（MBC）。结果黄连解毒汤对副溶血弧菌、金黄色葡萄球菌的MIC分别为62．5mg/mL、125．0m咖L,MBC分别为125．0mg/mL、125．0mg／mL;黄连解毒汤对福氏志贺菌、铜绿假单胞菌、大肠埃希菌、肺炎链球菌、伤寒沙门菌MIC均〉1000mg／mL。结论黄连解毒汤在体外对副溶血弧菌及金黄色葡萄球菌有显著的抗菌活性。     

黄芩中黄酮类化合物的抗菌作用

目的:观察黄芩总黄酮的体外抗菌活性。方法:采用试管连续稀释法对金黄色葡萄球菌等7个菌株进行有关黄芩总黄酮最低抑菌浓度(MIC)和最低杀菌浓度(MBC)的测定。结果:在体外抑菌实验中,黄芩总黄酮对金葡菌、葡萄球菌等革兰氏阳性细菌的抗菌作用强于对福氏志贺菌、甲型副伤寒沙门氏菌、大肠埃希氏菌和乙型副伤寒沙门氏菌等肠道致病菌的抗菌作用。结论:黄芩总黄酮对多种细菌具有明显的抑制作用。     

玉米须抗菌活性的初步研究

目的：探讨玉米须的体外抗菌活性。方法：采用琼脂扩散法和试管连续稀释法测定玉米须对常见致病菌和条件致病菌的体外抗菌活性及最低抑菌浓度（MIC）。结果：（1）玉米须对金黄色葡萄球菌和乙型溶血性链球菌皆有明显的抗菌活性，抑菌圈直径分别为21mm和16mm。对金黄色葡萄球菌的最低抑菌浓度为0．5g／ml。（2）玉米须对大肠埃希菌、福氏志贺氏菌、伤寒沙门氏菌、铜绿假单胞菌无抗菌活性。结论：玉米须对金黄色葡萄球菌和乙型溶血性链球菌有较好的体外抑菌活性。     

氯松霜抑菌试验分析

目的：对氯松霜进行体外抑菌试验。方法：最低抑菌浓度（MIC）测定，最低杀菌浓度（MBC）测定及抗菌效价测定。结果：氯松霜对金黄色葡萄球菌MIC为20μg/mL，MBC为30μg/mL，对铜绿假单胞菌MIC为40μg/mL，MBC为100μg/mL，表明该药对金黄色葡萄球菌及铜绿假单胞菌均有抗菌活性。但金黄色 葡萄球菌相对较敏感。     

两面针叶抗菌活性部位研究

目的研究两面针叶不同溶剂萃取部位对6种菌株的抗菌活性,为评价两面针叶抗菌活性部位提供实验依据。方法应用液体试管两倍稀释法测定两面针叶不同提取部位对大肠埃希菌、乙型副伤寒沙门菌、枯草芽孢杆菌、金黄色葡萄球菌、白色念珠菌、副溶血性弧菌等菌株进行最低抑菌浓度和最低杀菌浓度测定。结果乙酸乙酯部位对其中的4个菌株有抑菌活性,它们的抑菌活性依次为：副溶血性弧菌、白色念珠菌、金黄色葡萄球菌、枯草芽孢杆菌;正丁醇部位对白色念珠菌的抑菌活性最好,其最低杀菌浓度（MBC）和最低抑菌浓度（MIC）分别为750μg/mL和375μg/mL;水层对副溶血性弧菌抗菌活性最强;其MBC和MIC分别为750μg/mL和375μg/mL。结论乙酸乙酯部位、正丁醇部位及水层对白色念珠菌、副溶血性弧菌均有较好的抗菌活性,可考虑综合应用两面针叶在抗菌活性方面的应用与研究。     

盐酸头孢他美酯体外抗菌作用

目的：评价国产头孢他美酯对临床常见致病菌的体外抗菌活性。方法：采用试管二倍稀释法测定最低抑菌浓度（MIC）和采用肉汤二倍稀释平板活菌计数法测定最低杀菌浓度（MBC），并对其影响因素进行测定，同时与对照药头孢克洛进行对比。结果：盐酸头孢他美酯对化脓性链球菌、肺炎链球菌等革兰氏阳性菌，及对大肠杆菌、克雷伯氏肺炎杆菌、奇变形杆菌、沙门氏菌、志贺氏菌等革兰氏阴性菌均有较强的抗菌活性，其MIC50及MIC90的结果明显优于头孢克洛；对金黄色葡萄球菌、粪链球菌、绿脓杆菌的作用较差。结论：国产头孢他美酯对临床常见致病菌有良好的体外抗菌作用，其抗菌活性几乎不受培养基PH值及血清蛋白结合率的影响。     

梅丁消炎颗粒体外抗菌作用的研究

目的观察梅丁消炎颗粒的体外抗菌作用。方法采用琼脂扩散法、连续稀释法分别测定梅丁消炎颗粒的抑菌圈和最低杀菌浓度（MBC）。结果梅丁消炎颗粒对乙型溶血性链球菌、肺炎双球菌、金黄色葡萄球菌、化脓性链球菌等均有明显的体外抗菌作用。结论梅丁消炎颗粒对受试菌均有不同程度的抗菌作用,且抗菌谱较广,为临床治疗扁桃体炎、咽喉炎等提供了保证。     

壮药验方皮肤洗的体外抑菌作用研究

目的研究壮药验方皮肤洗对临床常见细菌的体外抑菌效果。方法采用微量肉汤稀释法,2,3,5-氯化三苯基四氮唑(TTC)显色法分别测定皮肤洗药液对金黄色葡萄球菌(SA)、大肠埃希菌、α-溶血性链球菌、表皮葡萄球菌、白色念珠菌的体外抑菌作用,测定5种实验菌种最低抑菌浓度(MIC)及最低杀菌浓度(MBC)。结果皮肤洗药液对实验菌株呈现不同程度的敏感,对金黄色葡萄球菌、大肠埃希菌、α-溶血性链球菌、表皮葡萄球菌、白色念珠菌的MIC分别为:31.25 mg/mL、125 mg/mL、31.25 mg/mL、3.91 mg/mL、500 mg/mL。皮肤洗药液对金黄色葡萄球菌、大肠埃希菌、α-溶血性链球菌、表皮葡萄球菌、白色念珠菌的MBC分别为:31.25 mg/mL、125 mg/mL、31.25 mg/mL、31.25 mg/mL、500 mg/mL。结论壮药验方皮肤洗具有较好的体外抗菌活性。     

肺感方体外抗菌活性的实验研究

目的：观察肺感方对11种临床常见病原菌的体外抗菌作用.方法：使用肉汤微量稀释法测定肺感方对不同菌株的最低抑菌浓度（MIC）及最低杀菌浓度（MBC）.结果：肺感方对标准金黄色葡萄球菌、铜绿假单胞菌、大肠埃希菌、肺炎克雷伯菌、阴沟肠球菌、铅黄肠球菌的MIC分别为62.5,62.5,125,31.25,250,500 g/L,相应的MBC为：62.5,62.5,250,31.25,500,1 000 g/L;对临床分离菌株鲍曼不动杆菌（多重耐药）、铜绿假单胞菌（多重耐药）的MIC和MBC均分别为250,500 g/L;对粪肠球菌、白色念珠菌、肺炎克雷伯菌（超广谱β内酰胺酶阳性）、大肠埃希菌（超广谱β内酰胺酶阳性）无明显体外抗菌作用.结论：肺感方对金黄色葡萄球菌、铜绿假单胞菌、大肠埃希菌、肺炎克雷伯菌、阴沟肠杆菌、铅黄肠球菌、鲍曼不动杆菌（多重耐药）及铜绿假单胞菌（多重耐药）具有体外抗菌作用,其中对肺炎克雷伯菌的抗菌活性最强.     

基于刃天青微平板法检测金黄色葡萄球菌对天然产物的敏感性

[目的] 以刃天青为检测试剂,评价大黄酸、棉子酚、盐酸小檗碱、兰雪醌、槲皮素5种天然产物对金黄色葡萄球菌的抑制作用。[方法] 比较刃天青浓度、菌悬液浓度、培养基种类和反应时间对吸光值的影响,优化刃天青的工作条件。刃天青法进行药敏性实验得到五种天然产物的最低抑菌浓度（MIC）,求得毒力回归方程、相关系数（R²）和半抑菌浓度（IC₅₀）。通过Z值判断刃天青显色法适用于高通量筛选药物的可行性。[结果] 当刃天青孔内终浓度为20μg/mL,培养基为LB,菌悬液浓度为5×10⁵CFU/mL,反应时间9h时适用于金黄色葡萄球菌的药敏性实验。刃天青显色法与微量肉汤法检测得到的五种天然产物的抑菌结果具有一致性。[结论] 五种天然产物均具有一定的抑菌活性。刃天青显色法具有准确性好、灵敏度高及高通量的特点,适用于天然产物抗菌活性的筛选。     

In vitro antibacterial activity of leaf extracts of Zehneria scabra and Ricinus communis against Escherichia coli and methicillin resistance Staphylococcus aureus

ObjectiveTo evaluate the antibacterial activities of the crude leaves extracts of Zehneria scabra (Z. scabra) and Ricinus communis (R. communis) against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and methicillin resistance S. aureus.MethodsThe crude powdered leaves of Z. scabra and R. communis were extracted successively by organic solvents in increasing polarity [benzene, chloroform:acetone (1:1), 70% alcohol and distilled water]. The antibacterial susceptibility of the crude leaves extracts of were tested against standard strains of E. coli (ATCC 25922) and S. aureus (ATCC 2923) and clinical isolates of E. coli, S. aureus and methicillin resistance S. aureus using agar well diffusion method.ResultsIn Z. scabra and R. communis leaf extracts, the most sensitive standard strain was S. aureus with an inhibition zone of (14.00±1.20) mm and (15.90±2.13) mm, respectively. The minimum inhibitory concentration (MIC) values of Z. scabra extracts against test organisms ranged from 1.95 mg/mL for extract 3 in clinical and standard strains of S. aureus to 250 mg/mL for extract 1 and 4 in clinical and standard strains of E. coli. The MIC values of R. communis extracts against test organisms ranged from 1.95 mg/mL for extract 2 and 3 standard strains of S. aureus to 250 mg/mL for extract 1 in clinical isolate of E. coli. Most of the minimum bactericidal concentration and MIC values of plant extracts were almost similar particularly in R. communis, or minimum bactericidal concentration equal to one dilution factor less than MIC value of the extracts mainly in Z. scabra.ConclusionsThe potency of plant extracts against test organisms were depend on different organic solvents used. Clinical isolate of bacterial pathogens showed less zones of diameter compared to the standard strains. Gram-positive had wide inhibition zones than Gram-negative bacteria. Further studies should be carried out to isolate the pure compounds and standardization of the methods of plant extracts for an in vitro testing.     

Studies on the antibacterial activity of Khaya senegalensis [(Desr.) A. Juss)] stem bark extract on Salmonella enterica subsp. enterica serovar Typhi [(ex Kauffmann and Edwards) Le Minor and Popoff]

ObjectiveTo study the phytochemical screening and antibacterial activity of the stem bark extracts of Khaya senegalensis (K. senegalensis) against Salmonella enterica subsp. enterica serovar Typhi.MethodsThe plant components were extracted using methanol, ethanol and water. The phytochemical screening of the stem bark extracts were carried out using a standard method. The antibacterial assay of the stem bark extracts against Salmonella Typhi (S. Typhi) using the agar well diffusion method with different concentrations of 50, 100, 200, 400 and 500 mg/mL and the corresponding concentrations of the control was carried out and the result compared with a standard antibiotic, amoxicillin as the control.ResultsThe results obtained from the phytochemical screening of the three plant bark extracts of K. senegalensis showed 10 plant secondary metabolites including saponins, tannins, reducing sugars, aldehyde, phlobatannins, flavonoids, terpenoids, alkaloids, cardiac glycoside and anthroquinones. The ethanol and aqueous extracts showed antibacterial activities against S. Typhi at concentration of 50 mg/mL with the zone diameter of inhibition (ZDI) of 14 mm and 15 mm respectively. The ethanol and aqueous extracts also showed zone diameter of inhibition of 23 mm and 25 mm respectively at 250 mg/mL and 27 mm each at 500 mg/mL. The ethanol and aqueous stem bark extracts gave the highest ZDI at 500 mg/mL while 100 mg/mL gave the least ZDI for ethanol extract and 50 mg/mL for the aqueous extract. This was followed by 400 mg/mL that gave 24 mm ZDI of the aqueous extract and 27 mm of the ethanol extract. The methanol extract showed intermediate susceptibility evidenced by ZDI of 10 mm at 100 mg/mL concentration. The methanol extract also showed antibacterial activity of 24 mm ZDI against the test organism at a higher concentration of 250 mg/mL and 26 mm at 500 mg/mL concentration. The methanol, ethanol and aqueous extracts displayed antibacterial activities against S. Typhi with a statistical significant difference at (P≤0.05). The extracts compared favourably with the standard antibiotic, the control. The minimum inhibitory concentration of the extracts was 250, 200, 200 and 100 mg/mL for methanol, ethanol, aqueous extracts and amoxicillin (control) respectively. The minimum lethal concentration of the extracts was 250, 250, 400 and 200 mg/mL for methanol, ethanol, aqueous extracts and control respectively.ConclusionsThe antibacterial properties of K. senegalensis stem bark extract can be harnessed for the production of new antibiotics or the enhancement of already existing antibiotics.     

Synergistic efficacies of thymoquinone and standard antibiotics against multi-drug resistant isolates

Objectives:To explore the antibacterial activity of thymoquinone (TQ), a quinone extracted from Nigella sativa.Methods:This study was conducted from May 2019 to March 2020 at the Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia. The antimicrobial activity, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC) of TQ were determined using an agar well diffusion method and broth microdilution assays, and the synergistic effect was evaluated using antibiotics in parallel. The disruptive effect of TQ on bacterial cell membranes was determined using scanning electron microscopy. The antivirulence properties of TQ, which include adherence and biofilm formation, were also investigated using adherence and biofilm formation assays, respectively.Results:Thymoquinone demonstrated bactericidal efficacy against 4/14 bacterial strains, with MIC range of 1.04-8.3 µg/mL and and MBC range of 10.41–66.66 µg/mL. Thymoquinone showed synergism against Klebsiella pneumoniae, Staphylococcus epidermidis (American Type Culture Collection 12228), Staphylococcus aureus, and Staphylococcus epidermidis in combination with the tested antibiotics. Thymoquinone inhibited bacterial adhesion by 39%-54%, 48%-68%, and 61%-81% at 0.5 × MIC, 1 × MIC, and 2 × MIC, respectively. The tested bacterial strains significantly inhibited biofilm formation after treatment with various concentrations of TQ for 24 and 48 hours.Conclusion:The combinatory effect of TQ with antimicrobials should be considered when developing new antimicrobial therapy regimens to overcome multidrug-resistant.     

Association between carriage of Streptococcus pneumoniae and Staphylococcus aureus in Children

Context  Widespread pneumococcal conjugate vaccination may bring about epidemiologic changes in upper respiratory tract flora of children. Of particular significance may be an interaction between Streptococcus pneumoniae and Staphylococcus aureus, in view of the recent emergence of community-acquired methicillin-resistant S aureus. Objective  To examine the prevalence and risk factors of carriage of S pneumoniae and S aureus in the prevaccination era in young children. Design, Setting, and Patients  Cross-sectional surveillance study of nasopharyngeal carriage of S pneumoniae and nasal carriage of S aureus by 790 children aged 40 months or younger seen at primary care clinics in central Israel during February 2002. Main Outcome Measures  Carriage rates of S pneumoniae (by serotype) and S aureus; risk factors associated with carriage of each pathogen. Results  Among 790 children screened, 43% carried S pneumoniae and 10% carried S aureus. Staphylococcus aureus carriage among S pneumoniae carriers was 6.5% vs 12.9% in S pneumoniae noncarriers. Streptococcus pneumoniae carriage among S aureus carriers was 27.5% vs 44.8% in S aureus noncarriers. Only 2.8% carried both pathogens concomitantly vs 4.3% expected dual carriage (P = .03). Risk factors for S pneumoniae carriage (attending day care, having young siblings, and age older than 3 months) were negatively associated with S aureus carriage. Conclusions  Streptococcus pneumoniae carriage, specifically of vaccine-type strains, is negatively associated with S aureus carriage in children. The implications of these findings in the pneumococcal vaccine era require further investigation.      

In vitro control of Staphylococcus aureus (NCTC 6571) and Escherichia coli (ATCC 25922) by Ricinus communis L.

Objective

To evaluate antibacterial activity of hot and cold ethanol and methanol leaf extracts of Ricinus communis L (R. communis) against Staphylococcus aureus (S. aureus) (NCTC 6571) and Escherichia coli (E. coli) (ATCC 25922).

Methods

Leaf powder of R. communis L. was extracted with hot (in Soxhlet) and cold ethanol and methanol, separately. The antibacterial activity of the extracts was determined by agar well diffusion and macro broth dilution methods. The extracts were also subjected to phytochemical analysis.

Results

All the four test extracts showed inhibition on both S. aureus and E. coli. Hot and cold ethanol extracts revealed significantly (P<0.05) higher inhibition on S. aureus than methanol extracts, and the hot ethanol extract had the lowest minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values (5 mg/mL and 10 mg/mL, respectively). E. coli was highly inhibited by hot extracts of both ethanol and methanol with the MIC and MBC of 40 mg/mL and 80 mg/mL, respectively. Phytochemical analysis revealed the presence of saponins, cardiac glycosides, tannins, flavonoids and terpenoids in all test extracts.

Conclusions

This study demonstrates that the hot and cold methanol and ethanol extracts are potential sources for control of S. aureus and E. coli. Especially, the hot and cold extracts of ethanol are more inhibitive against S. aureus even at lower concentration. Further study is needed to identify the specific bioactive compounds, their mode of action and their nontoxic nature in vivo condition.     

单纯性浅表皮肤感染小鼠模型的建立及有效性验证

建立与临床上单纯性浅表皮肤感染较为接近的小鼠模型,便于致病机制和外用抗菌药物筛选及疗效观察研究。选用BALB/c小鼠,采用胶带反复粘贴法破坏局部皮肤屏障,通过皮肤水分流失(TEWL)值标定皮肤屏障破坏程度,然后在其创面接种金黄色葡萄球菌(7.5×10⁶ CFU/mL)及化脓性链球菌(1.5×10⁸ CFU/mL),建立局部皮肤的实验感染模型,并给予氧氟沙星凝胶以验证模型的敏感性和有效性。结果显示:胶带反复粘贴7次和10次分别为金黄色葡萄球菌和化脓性链球菌感染前皮肤屏障破坏的最佳次数;6株金黄色葡萄球菌和3株化脓性链球菌局部感染后,创面活菌培养结果分别为4.99±4.74、5.52±5.45、4.92±4.56、5.24±4.84、5.20±5.01、4.94±4.69和4.82±4.87、5.34±5.45、4.63±4.41 CFU/g,与对照组比较差异均有统计学意义(P<0.01)。给予氧氟沙星凝胶后,对感染灶细菌生长的抑制率均大于80%。结果表明,所建立的皮肤浅表感染模型具有一定的敏感性和有效性,对皮肤浅表感染发病机制研究、外用抗菌药物筛选和疗效观察具有一定的应用前景。     

2013年~2015年广东地区实验小鼠和大鼠微生物学及寄生虫学调查

目的 调查2013~2015年广东地区实验小鼠和大鼠的病原携带情况。方法 本文涉及的样品主要来源于监督检测的抽样样品和委托检测的送样样品,共收集到广东省12家监督单位和32家委托单位样品。按照国家标准要求的项目及标准外的螺杆菌和小鼠诺如病毒进行检测。结果 监督检测和委托检测结果存在较大差异。3年中监督检测的小鼠检出4种病原,包括绿脓杆菌（0.7%）、嗜肺巴斯德杆菌（0.3%）、肺炎克雷伯杆菌（0.7%）和鞭毛虫（1.7%）,未检出病毒;大鼠检出1种病原即嗜肺巴斯德杆菌（1.1%）,未检出病毒和寄生虫。委托检测的小鼠检出15种病原,包括绿脓杆菌（3.7%）、嗜肺巴斯德杆菌（5.2%）、支原体（1.9%）、金黄色葡萄球菌（0.7%）、肺炎克雷伯杆菌（0.8%）、螺杆菌（45.3%）,小鼠肝炎病毒（8.5%）、小鼠脑脊髓炎病毒（7.0%）、小鼠诺如病毒（16.2%）、鼠痘病毒（0.3%）、小鼠细小病毒（0.5%）、仙台病毒（0.1%）、鞭毛虫（11.7%）、蠕虫（1.0%）、体外寄生虫（0.1%）。大鼠检出8种病原,包括绿脓杆菌（3.4%）、嗜肺巴斯德杆菌（8.6%）、支原体（0.9%）、金黄色葡萄球菌（2.9%）、泰泽病原体（4.8%）、大肠杆菌（1.0%）、大鼠细小病毒H-1株（3.0%）、大鼠冠状病毒（1.0%）,未检出寄生虫。其中,实验小鼠7种病原,包括绿脓杆菌、嗜肺巴斯德杆菌、螺杆菌、鞭毛虫、小鼠肝炎病毒、小鼠脑脊髓炎病毒和小鼠诺如病毒,大鼠2种病原,包括金黄色葡萄球菌和泰泽病原体,检出范围广、检出率较高,而且存在区域分布特点,即设施污染后能在多次送检的动物中检出这些病原。结论 本研究获得广东省实验大小鼠病原流行情况和分布,这些数据的统计为我国实验动物质量标准的制订提供基础数据,同时也为各动物实验设施的质量控制方案制订提供依据。     

三种生物碱体外抑菌活性的测定

目的：研究甜菜碱、苦参碱、氧化苦参碱对金黄色葡萄球菌、大肠杆菌、铜绿假单胞菌和白色念珠菌的体外抑菌活性。方法：采用试管二倍稀释法进行体外抑菌试验,测定苦参碱和氧化苦参碱对上述4种病原菌的最小抑菌浓度（MIC）。结果：体外实验结果表明,对大肠杆菌、铜绿假单胞菌、金黄色葡萄球菌和白色念珠菌四种病原菌标准菌株的MIC：甜菜碱分别是6.25、3.125、6.252、5 mg/mL;苦参碱分别是12.5、25、252、5 mg/mL;氧化苦参碱均大于50 mg/mL。结论：三种生物碱在体外对受试菌具有不同程度的抑菌作用,其中甜菜碱对上述四种病原菌的体外抑菌效果较苦参碱和氧化苦参碱要好。     

神香苏合丸对心肌梗死大鼠肠道菌群的影响

[目的]探索神香苏合丸对心肌梗死大鼠肠道菌群的影响.[方法]运用16S扩增子测序技术检测神香苏合丸给药14 d后各组心肌梗死大鼠肠道菌群的变化,通过体外培养实验检测神香苏合丸对关键肠道微生物生长的影响.[结果]神香苏合丸对心肌梗死大鼠肠道菌群具有改善作用,主要表现为降低心肌梗死大鼠肠道中厚壁菌门丰度,增加拟杆菌门丰度,...     

消岩汤剂拆方配伍对A549肺腺癌细胞体外生长抑制作用研究

[目的] 探讨消岩汤及各拆方组对人肺腺癌 A549细胞的体外生长的作用机制,探究消岩汤剂中最有效的作用成分和浓度。[方法] 消岩汤全方和根据功效拆分的清热解毒组、活血化瘀组、益气扶正组,以CCK-8检测A549肺腺癌细胞的细胞增殖活性。[结果] 各组均有明显的抑制细胞活性作用,抑制强度依次为:全方组、清热解毒组、活血化瘀组、益气扶正组。[结论] 消岩汤及其拆方组在体外实验中均能抑制A549肺腺癌细胞细胞生长,消岩汤全方组当浓度达到50 g/L时达到最大抑制率为85.60%。清热解毒组药物在抗肿瘤作用方面,与全方接近,提示清热解毒组中药为体外实验中全方抗肿瘤作用最有效组分。