复方丹参的体外抗氧化活性研究

目的探讨复方丹参的体外抗氧化活性。方法采用DPPH自由基、超氧阴离子、羟基自由基、鳌合亚铁离子和还原力、过氧化氢的反应体系,检测了复方丹参的体外抗氧化活性,并与维生素C进行比较。结果复方丹参和维生素C消除DPPH自由基的EC50分别是41.0μg/mL和8.2μg/mL;复方丹参消除超氧阴离子自由基的EC50是1.39 m g/mL;复方丹参和维生素C抑制羟基自由基产生的EC50分别是1.73 m g/mL和0.58 m g/mL;在实验体系中,未检测到复方丹参螯合亚铁离子的能力;复方丹参和维生素C的还原能力的EC50分别是0.42 m g/mL和0.08 m g/mL。在实验最高质量浓度100μg/mL时,复方丹参和维生素C对过氧化氢的清除率分别为36%和94%。结论复方丹参具有较强还原力,能清除DPPH和超氧阴离子自由基的作用,并抑制羟基自由基的产生。复方丹参的多方面抗氧化活性可能是在治疗心血管疾病效果显著的原因之一。     

妇科活血止痛颗粒的体外抑菌作用

目的:考察妇科活血止痛颗粒的体外抑菌作用.方法:采用双倍稀释法,以妇乐颗粒为对照药,测定妇科活血止痛颗粒对金黄色葡萄球菌、大肠埃希菌、铜绿假单胞菌、乙型溶血性链球菌、白色念珠菌的体外最低抑菌浓度(MIC).结果:妇科活血止痛颗粒对金黄色葡萄球菌、大肠埃希菌、乙型溶血性链球菌、白色念珠菌的体外抑菌作用较强,对铜绿假单胞菌的体外抑菌作用稍弱.结论:妇科活血止痛颗粒对金黄色葡萄球菌、大肠埃希菌、铜绿假单胞菌、乙型溶血性链球菌、白色念珠菌均具有良好的体外抑菌作用,且效果优于妇乐颗粒.     

II. In vitro studies of antibacterial activity

One hundred and forty isolates of beta-hemolytic streptococcus cultured from patients with clinical pharyngitis were studied by disc diffusion for antibiotic sensitivity to lincomycin, erythromycin, cephalexin and penicillin and by agar dilution to cephalexin and penicillin. All isolates were sensitive to ≤ 0.1 μg./ml. penicillin and ≤ 1.56 μg./ml. cephalexin. The disc-diffusion test was reliable in predicting the sensitivities in vitro. One strain of group A betahemolytic streptococcus was resistant to erythromycin by disc diffusion. When compared to Lancefield grouping 18% of strains were incorrectly identified as group A by the bacitracin-disc test. Cephalexin was uniformly effective in vitro in inhibiting beta-hemolytic streptococci and the 30 μg. cephalexin disc was reliable in predicting these sensitivities.     

芙蓉菊多糖体外抗氧化活性研究

目的 研究芙蓉菊多糖的体外抗氧化活性。方法 采用1,1-二苯基苦基苯肼（DPPH）自由基、还原力、超氧阴离子、羟自由基4种体外抗氧化模型研究芙蓉菊多糖的抗氧化活性,用维生素C作对照。结果 芙蓉菊粗多糖对DPPH自由基、还原力、超氧阴离子、羟自由基均有明显的清除能力,其中DPPH、超氧阴离子、羟自由基的EC50值分别为0.273、0.669、0.594 mg/mL,对羟自由基清除能力强于维生素C。芙蓉菊多糖对自由基清除率与其质量浓度存在着明显的量效关系。结论 芙蓉菊多糖具有良好的体外抗氧化活性,作为天然抗氧化剂和自由基清除剂有进一步研究的价值。     

米替福新对常见皮肤癣菌体外抑菌活性的研究

目的 了解米替福新对常见皮肤癣菌的体外抑菌活性.方法 参照美国临床和实验室标准化研究所(CLSI)制定的M 38-A方案测定77株常见皮肤癣菌(含三属即毛癣菌属、小孢子菌属和表皮癣菌属)的最低抑菌浓度(MIC).结果 米替福新对常见皮肤癣菌均有较好的抑菌作用,MIC90为1.0 μg/ml,MIC几何均数为0.617 μg/ml,MIC范围0.25～2.0 μg/ml.结论 米替福新对常见皮肤癣菌各属均有较好的抑菌作用.     

新的苄胺类化合物的合成及其体外抗真菌活性

目的：研究在萘环侧链α位引入大基团（三唑甲基）对苄胺类化合物抗真菌活性的影响。方法：设计合成了９个新的苄胺类化合物。选择６种临床致病真菌为试验菌株,观察本类化合物对它们的体外抑制活性。结果：新化合物的抗真菌活性低于对照药物布替萘芬。结论：在萘环侧链α位引入大基团（三唑甲基）降低了苄胺类化合物的抗真菌活性。     

20种四氢萘类抗真菌化合物体外抑菌活性测定

目的:考察20种四氢萘类化合物体外抗真菌活性.方法:采用NCCLS的M27-A方案,以不同氟康唑敏感性的念珠菌及非念珠菌为供试菌进行体外药敏试验.对化合物22-1、31-1及其盐酸盐22、31,还有化合物34-1、26-1及其溴酸盐34、26进行时间生长曲线实验以及与其他结构抗真菌药进行体外联合药敏试验.结果:该类化合物均具一定抗真菌活性,尤其是化合物31-1对氟康唑敏感白念珠菌的抑菌活性明显强于氟康唑,持续抑菌时间超过54 h;化合物22和22-1对氟康唑耐药白念珠菌及近平滑念珠菌和红色毛癣菌作用强大,MIC50值均＜0.125 μg/ml,对于氟康唑耐药的白念珠菌抑菌活性强于酮康唑.此类药物与小檗碱或特比萘芬联用可产生协同作用.结论:四氢萘类化合物结构新颖,体外抗真菌活性显著,值得进一步研究开发.     

In vitro and in vivo antibacterial activity of Pogostone

Background Our pervious antibacterial studies on several traditional Chinese medicines have found that Patchouli oil from Pogostemon cablin had significant antibacterial activity against methicillin-resistant Staphylococcus aureus （MRSA）,which has spread worldwide and infected innumerable people.In order to find the more active natural substances in Patchouli oil,one of the major components,Pogostone,was isolated and its antibacterial activity was evaluated in vitro and in vivo in this study.Methods In vitro test,Pogostone was screened for antimicrobial properties against 83 bacteria comprising 35 gram positive and 48 gram negative bacteria strains via the agar double dilution method.In vivo test,specific pathogen free （SPF） strain of both male and female white Kunming mice,weighing 18-22 g,were used to test the protective ability of Pogostone after being injected with the median lethal doses （MLDs） of the tested strains.Results In vitro test,Pogostone could inhibit both gram negative bacteria （0.098-1 600 μg/ml） and gram positive bacteria（0.098-800 μg/ml）.For Corynebacterium xerosis and some Chryseobacterium indologenes,the minimum inhibitory concentration （MIC） values of Pogostone were extremely low （＜0.098 μg/ml）.It was significant that Pogostone was also active against some drug-resistant bacteria like MRSA.Furthermore,Pogostone showed antibacterial activity in vivo against Escherichia coli （E.coli） and MRSA via intraperitoneal injection.Ninety percent of the mice infected with E.coil could be protected at the concentrations of 50 and 100 mg/kg,and 60％ of the mice at 25 mg/kg,while the rate of protection for the mice infected with MRSA was 60％ and 50％ at doses of 100 and 50 mg/kg,respectively.Conclusion Pogostone could be developed as a potential antibacterial agent for clinical therapy.     

磷霉素对革兰阴性菌的体外抗菌活性研究

[目的] 了解磷霉素对革兰阴性菌的体外抗菌活性.[方法] 应用K-B纸片扩散法对革兰阴性菌进行体外敏感性实验.[结果] 大肠埃希菌、肺炎克雷伯菌、阴沟肠杆菌和产气肠杆菌对磷霉素耐药率为10%～22%;其他肠杆菌、铜绿假单胞菌及鲍曼不动杆菌分别为35%～41%、71%和95%.产ESBLs的大肠埃希菌和肺炎克雷伯菌对磷霉素的耐药率为16%和22%;肺炎克雷伯产酶菌耐药率(22%)明显高于非产酶菌(4%).对磷霉素敏感株而言,磷霉素对大肠埃希菌抑菌环直径远大于肺炎克雷伯菌.[结论] 对产ESBLs大肠埃希菌、肺炎雷伯菌、阴沟肠杆菌和产气肠杆菌引起的感染,可选用磷霉素,磷霉素对大肠埃希菌的抗菌活性高于肺炎克雷伯菌.对非发酵菌则不宜选用磷霉素进行临床治疗.     

In vitro antimicrobial activity of mangrove plant Sonneratia alba

Objective

To investigate the antimicrobial property of mangrove plant Sonneratia alba (S. alba).

Methods

The antimicrobial activity was evaluated using disc diffusion and microdilution methods against six microorganisms. Soxhlet apparatus was used for extraction with a series of solvents, n-hexane, ethyl acetate and methanol in sequence of increasing polarity.

Results

Methanol extract appeared to be the most effective extract while n-hexane extract showed no activity. The antimicrobial activities were observed against the gram positive bacteria Staphylococcus aureus (S. aureus) and Bacillus cereus (B. cereus), the gram negative Escherichia coli (E. coli) and the yeast Cryptococcus neoformans. Pseudomonas aeruginosa and Candida albicans appeared to be not sensitive to the concentrations tested since no inhibition zone was observed. E. coli (17.5 mm) appeared to be the most sensitive strain followed by S. aureus (12.5 mm) and B. cereus (12.5 mm).

Conclusions

From this study, it can be concluded that S. alba exhibits antimicrobial activities against certain microorganisms.     

In vitro activity of natural honey alone and in combination with curcuma starch against Rhodotorula mucilaginosa in correlation with bioactive compounds and diastase activity

Objective

To evaluate the in vitro activity and synergism of the combinations of natural honey and curcuma starch against Rhodotorula mucilaginosa in correlation with total phenolic, flavonoid contents, and diastase activity.

Methods

The Folin-Ciocalteu test was used to determine the total polyphenols content and the flavonoid content was analyzed using by the aluminum chloride method. The antifungal activity of the natural honey, determined by an agar well diffusion assay and agar incorporation method.

Results

Total phenolic content varied from (63.93±0.11) to (95.36±6.08) mg GAE/100 g honey as gallic acid equivalent. Total flavonoids content varied from (5.41±0.04) to (9.94±0.54) mg CE/100 g. Diastase activity values were between (7.3±2.8) and (26±2.8). The zone inhibition diameter for the six honey samples without starch ranged between 6 and 20 mm. When starch was mixed with honey and then added to well, a zone inhibition increase diameter 7 and 21 mm. The percentage increase was noticed with each variety and it ranged between 5% and 62.5%. The minimal inhibitory concentrations for the six varieties of honey without starch against Rhodotorula mucilaginosa ranged between 28% and 36% (v/v). When starch was incubated with honey and then added to media, a minimal inhibitory concentration drop has been noticed with each variety. It ranged between 6.66 % and 20% (w/v). No significant correlation was established between diastase activity and bioactive compounds.

Conclusions

The mixture of curcuma starch and honey could lead to the development of new combination antibiotics against Rhodotorula infections     

铬还原酶T体外合成及活性鉴定

目的：克隆沙雷氏菌CQMUS2中铬还原酶T（Chromate reductase T,ChrT）的全基因,构建其原核表达载体并转化至大肠杆菌中表达蛋白,分析表达产物的活性。方法：应用PCR技术,以耐铬沙雷氏菌CQMUS2基因组DNA为模板扩增ChrT全基因,将该基因连接至表达载体pET-28a（+）并转化进大肠杆菌感受态细胞E.coli BL21（DE3）表达,用酶促反应鉴定重组ChrT酶的活性和Cr（Ⅵ）还原能力,探索其最适pH和温度。结果：克隆出的ChrT全基因长为567 bp,编码188个氨基酸,分子量约20 kD;IPTG诱导10 h后,在大肠杆菌中成功表达了目的蛋白,其碱基序列和分子量与ChrT酶一致;纯化后,ChrT酶能还原酶促反应体系中的Cr（Ⅵ）,使实验组Cr（Ⅵ）含量明显低于对照组（P＝0.000）,其酶活可达997 U/L;ChrT酶的最适pH为6.5~7.5,最适温度为37 ℃。结论：ChrT酶具有Cr（Ⅵ） 还原活性,为进一步研究高效除铬基因工程菌奠定了基础。     

荧光测定法体外快速筛选抗肿瘤活性物质的研究

目的:建立一种基于FDA荧光信号的体外快速筛选抗肿瘤活性物质的方法。方法:通过筛选合适的FDA浓度,建立了荧光测定法,并对该方法进行了线性范围和精密度的考察以及可靠性验证。应用本方法对两种药用植物的抗肿瘤活性部位进行了初筛。结果:该方法在68~1.5×10~4个/孔的范围内,荧光信号强度与细胞数之间具有良好的线性关系(R~2=0.996 7),板内精密度为10.9%。应用本方法检测得到盐酸阿霉素抑制MCF-7细胞增殖的IC_(50)值为3.04μg/mL,说明本方法用于抗肿瘤活性物质筛选是准确可靠的。经过本方法的筛选,获得了沙煲暗罗茎乙酸乙酯部位、沙煲暗罗茎石油醚部位和海南染木树石油醚部位抑制MCF-7细胞增殖的IC_(50)值分别为134.1μg/mL、78.46μg/mL和86.87μg/mL。结论:本方法快速、灵敏、细胞线性范围宽,可用于天然产物抗肿瘤活性物质的体外快速高通量筛选。