中草药蒲公英的体外抑菌试验

研究了中草药蒲公英的体外抑菌作用。对蒲公英水提物采用琼脂平板扩散法、试管二倍稀释法进行试验。实验得出,蒲公英对金黄色葡萄球菌和大肠杆菌的最低抑菌浓度(MIC)均为54.19mg/mL,最低杀菌浓度(MBC)均为216.75mg/mL;对绿脓杆菌的MIC为54.19mg/mL,MBC为108.38mg/mL;对粪肠球菌的MIC为108.38mg/mL,MBC 433.50mg/mL。结果表明,中草药蒲公英的水提物对金黄色葡萄球菌、大肠杆菌、绿脓杆菌、粪肠球菌均具有体外抑菌作用。     

金银花叶的抑菌活性和抗氧化性研究

采用滤纸片法和D值计算法研究了金银花叶中天然抗菌物质的体外抑菌活性,采用分光光度法测定了其抗羟自由基的氧化活性。抑菌实验结果表明,金银花叶的乙醇提取物抗菌谱较广;乙醇提取物水溶液的乙酸乙酯萃取物抑菌效果最为显著,测得其对金黄色葡萄球菌和大肠杆菌的最低抑菌浓度分别为0．38％和0．50％。抗氧化实验结果表明,金银花叶乙醇提取物具有一定的抗羟自由基氧化活性,其乙酸乙酯萃取物在1mg／mL的低浓度下就显示出了较好的效果。     

无患子提取物对痤疮丙酸杆菌的抑制作用及其应用研究

以无患子果皮为原料,采取水提发酵结合乙酸乙酯萃取工艺提取活性成分,得到无患子乙酸乙酯萃取物(EAWF)抑制痤疮丙酸杆菌ATCC 6919(Propionibacterium acnes ATCC 6919,以下简称P. acnes ATCC 6919)的最低抑菌浓度(MIC)和最低杀菌浓度(MBC)均为0.25mg/mL;并且当其浓度为2.00 mg/mL时,对供试菌的抑制率达100%。此外,实验将无患子发酵浓缩液(SFW)添加至水洗面膜基质中,研究其添加量对面膜的pH、黏度及抑菌性的影响。结果表明,在所选的添加量范围内(10%～40%),面膜的pH变化范围为6.70～6.89,黏度为19.12～29.06Pa·s,并且对P. acnes ATCC 6919抑制作用具有浓度依赖性(r=0.991)。感官评定结果得出,在水洗面膜中加入15%的SFW的感官评分最高,其色泽良好,质地均匀,干燥时间适宜,且具有较好的保湿性。     

啶菌恶唑体外抑真菌研究

应用二倍试管稀释法测定了啶菌恶唑对石膏样毛癣菌的体外最小抑菌浓度(MIC)和最小杀菌浓度(MBC)及其最小杀菌曲线，并对培养基的pH值和菌液浓度对啶菌恶唑抑菌效果的影响进行了研究。结果表明啶菌恶唑的MIC及MBC分别为0．63mg／ml、5mg／ml。随着培养时间的延长，时间-杀菌曲线显示了从抑菌到杀菌的趋势。MIC及MBC值随着菌液浓度的增加及培养基pH值的降低而增加。     

香水莲花醇提取物对酪氨酸酶抑制作用的研究

以L-酪氨酸为底物,从马铃薯中提取酪氨酸酶,以熊果苷为阳性对照,采用比色法测定了香水莲花醇提取物对酪氨酸酶的抑制率。结果：香水莲花花托醇提取物、雄蕊醇提取物及总醇提取物的半数抑制浓度分别为0．12mg／mL、0．13mg／mL和0．48mg／mL,而阳性对照品熊果苷的半数抑制浓度为0．42mg／mL。表明,香水莲花花托醇、雄蕊醇提取物具有良好的抑制酪氨酸酶的作用,其效果优于熊果苷。香水莲花总醇提取物对酪氨酸酶的抑制作用与熊果苷相当。     

离子交换法提取发酵乳酸的单级工艺条件优化研究

通过树脂选型,选用弱阴离子树脂D301G和D311从发酵液中提取乳酸，研究过程中对时间、发酵液浓度、转速、pH等影响因素加以系统考察。通过单级工艺研究最佳操作条件为：时间为3h、发酵液浓度为86．0g／L、pH为3，此时交换容量为237mg／g.     

高效液相色谱法测定柠檬酸的含量

建立了一种准确对发酵液中柠檬酸含量测定的仪器方法,在检测范围6-16 mg/mL之间成线性,R=0.999 7,RSD为±0.8%-1.2%(n=6),最低检测浓度为0.02 mg/mL.此方法简单、灵敏、重现性好,避免了由于化学转化所引起的测定误差,以及发酵液中色素的影响.     

异质性万古霉素耐药金黄色葡萄球菌的抗生素后效应

目的 了解异质性万古霉素耐药金黄色葡萄球茵(h-VRSA)对万古霉素的抗生素后效应(PAE)等药代动力学特点,探讨h-VRSA的存在,对万古霉素的杀菌活性及其临床应用方面的影响.方法 分别检测ATCC 29213和h-VRSA(原代培养)的最低抑菌浓度(MIC).最低杀菌浓度(MBC)以及PAE.结果 ATCC 29213的MIC和MHC分别为1 μ g/mL和16μg,/mL,h-VRSA(原代)的MIC和MBC分别为2μg/mL和64μg/mL;两者PAE分别为0.9 h和2.2 h.结论 与ATCC29213不同,h-VRSA的PAE明显延长;MIC为2μg/mL的h-VRSA其MBC可以达到64 μ g/mL,已经高于万古霉素的有效血药浓度峰值(20-40)μg/mL;提示单独使用万古霉素已经不能完全清除h-VRSA.     

DO浓度对生活污水硝化过程中N2O产生量的影响

为确定污水脱氮过程中最优的DO浓度和曝气方式,以提高污水处理效率,降低N2O产生量,采用实际生活污水应用小试SBR反应器,重点考察了不同DO浓度条件下,硝化效率和硝化过程中N2O的产生量,结果表明,当DO浓度恒定为0．4mg／L时,虽然硝化过程所消耗的能量最低,但其氨氮氧化的速率较低。提高DO浓度,氨氮氧化速率可随之升高。低氨氮生活污水硝化过程中仍有N2O产生。DO浓度为0．4mg／L和0．9mg／L时,污水N2O产生量（以N计）分别为1．5mg／L和1．6mg／L;而DO浓度为1．5mg／L和2．0mg／L时,N2O产生量则分别降低至0．5mg／L和0．4mg／L。     

Fe浸渍污泥生物炭对含Cd(Ⅱ)废水的吸附性能研究

通过城市污泥热解制备污泥生物炭(BC),采用FeCl_3溶液浸渍污泥生物炭后制备出磁性污泥生物炭(MBC),对比了BC与MBC去除水溶液中Cd(Ⅱ)的能力。考察溶液初始pH、吸附时间、吸附温度以及Cd(Ⅱ)初始浓度对BC和MBC去除Cd(Ⅱ)效果的影响。结果表明,BC和MBC均符合拟二级动力学吸附模型;Langmuir吸附等温模型能够更好地描述BC和MBC去除Cd(Ⅱ)的过程。在溶液初始pH为6.0,生物炭投加量为10 mg,Cd(Ⅱ)质量浓度为10～150 mg/L的溶液25 mL,吸附时间为360 min,温度为25℃的最佳条件下,BC和MBC对Cd(Ⅱ)最大的吸附量分别为76.93 mg/g和167.42 mg/g。经过5次吸附解吸试验,MBC的Cd(Ⅱ)去除率保持在90%以上,BC的Cd(Ⅱ)去除率在55%左右,说明MBC具有更好应用于去除含Cd(Ⅱ)废水的能力。     

吴茱萸柠檬苦素提取物的抑菌效果研究

采用稀释法研究了吴茱萸柠檬苦素提取物的最低抑菌浓度（MIC）和最低杀菌浓度（MBC）,并采用滤纸片法对吴茱萸柠檬苦素提取物和吴茱萸的醇提物的抑菌活性进行了对比研究。试验结果表明吴茱萸柠檬苦素提取物对藤黄微球菌、沙门氏菌、痢疾志贺氏菌、柠檬酸杆菌的抑菌效果及杀菌效果较好,其中吴茱萸柠檬苦素提取物的抑菌杀菌效果明显高于同浓...     

Interactions of antibiotics and methanolic crude extracts of afzelia africana (smith.) against drug resistance bacterial isolates

Infection due to multidrug resistance pathogens is difficult to manage due to bacterial virulence factors and because of a relatively limited choice of antimicrobial agents. Thus, it is imperative to discover fresh antimicrobials or new practices that are effective for the treatment of infectious diseases caused by drug-resistant microorganisms. The objective of this experiment is to investigate for synergistic outcomes when crude methanolic extract of the stem bark of Afzelia africana and antibiotics were combined against a panel of antibiotic resistant bacterial strains that have been implicated in infections. Standard microbiological protocols were used to determine the minimum inhibitory concentrations (MICs) of the extract and antibiotics, as well as to investigate the effect of combinations of the methanolic extract of A. africana stem bark and selected antibiotics using the time-kill assay method. The extract of Afzelia africana exhibited antibacterial activities against both Gram-negative and Gram-positive bacteria made up of environmental and standard strains at a screening concentration of 5 mg/mL. The MICs of the crude extracts and the antibiotics varied between 1 μg/mL and 5.0 mg/mL. Overall, synergistic response constituted about 63.79% of all manner of combinations of extract and antibiotics against all test organisms; antagonism was not detected among the 176 tests carried out. The extract from A. africana stem bark showed potentials of synergy in combination with antibiotics against strains of pathogenic bacteria. The detection of synergy between the extract and antibiotics demonstrates the potential of this plant as a source of antibiotic resistance modulating compounds.     

中药白芨提取物对酪氨酸酶的抑制作用

通过从水和乙醇中选取一种有效的提取剂,用回流法和超声波提取法提取中药白芨中的有效成分,分别以左旋多巴(L-DOPA)、邻苯二酚为底物,研究了白芨提取物对酪氨酸酶活性的影响。结果表明,白芨提取物对酪氨酸酶活性有抑制作用,66.7 mg/mL的超声波水提取物比醇提取物对酪氨酸酶有更为明显的抑制作用,其对酪氨酸酶的抑制率为62%,IC50值为28 mg/mL。     

In vitro Antimicrobial Activity of Ozonized Theobroma Oil Against Candida albicans

In this paper, a study of antimicrobial activity of ozonized theobroma oil against Candida albicans was carried out. Minimum inhibitory concentration and minimum fungicide concentration from ozonized theobroma oil for several peroxides indexes were determined. Mortality kinetics for peroxide index of 1200 mmol-eq/kg was carried out. Effect of contact time, peroxide index and ozonized theobroma oil concentration on Candida albicans mortality was studied. Under the conditions studied, minimum inhibitory concentration and minimum fungicide concentration values between 5 and 3.75 mg/mL and 11.58 and 5.78 mg/mL were obtained for peroxides indexes of 1002 and 1200 mmol-eq/kg of sample, respectively.

Microorganism inactivation follows first order kinetics. An optimal concentration value of 93.75 mg/mL was obtained. Further increases of ozonized theobroma oil concentration did not exert any influence on mortality. Under the variables ranges studied all parameters have a significant effect on the mortality of Candida albicans, contact time being the most important factor.     

Functional properties of hot water extract of a fish,seaweed, and mushroom mixture

The purpose of this study was to evaluate the effect of hot water extracts of a fish, seaweed, and mushroom mixture (FSM extract) on the antioxidant and anticancer activities for use as health and functional food resources. DPPH radical scavenging activity increased from 13.4 to 93.5% when the FSM extract concentration ranged from 0.5 to 25 mg/mL. The reducing power increased from 0.04 to 1.06 OD 700 nm when the FSM extract concentration increased from 0.25 to 10 mg/mL. Nitrite scavenging activity increased from 10.3 to 96.9% when the FSM extract concentration increased from 1 to 25 mg/mL. The activities of alcohol dehydrogenase and acetaldehyde dehydrogenase in the FSM extractfed group were 2.45 and 6.12 units/min, respectively. The activities of CAT, SOD, and GSH-Px in the FSM extractfed group were 19.7 units/mg protein, 11.5 units/mg protein, and 16.9 units/mg protein/min, respectively. Cell viabilities of SNU213, SNU324, and SNU354 were 7.5, 9.4, and 8.9%, respectively. Cell viabilities of SNU719, SNU1, and SNU5 ranged from 14.6 to 16.8%. However, for SNU216, SNU484, SNU601, SNU638, SNU668, SNU16, and SNU520, they were below10%. These results demonstrate that the FSM extract can be used in the functional food, pharmaceutical, and cosmetic industries.     

Potential application of acetone extract of <Emphasis Type="Italic">Astragalus sinicus</Emphasis> Linne seed to functional cosmetics

For the functional cosmetic agent using acetone extract of A. sinicus Linne seed, the effects of whitening, wrinkling, and safety were investigated. Cell viabilities of Raw 264.7 up to 60 mg/mL did not appear to have any significant direct cytotoxic effect. The melanin concentration was decreased up to 62.1% at 20 mg/mL. When the acetone extract concentration of A. sinicus Linne seed was increased from 5 to 20 mg/mL, the inhibitory activity of tyrosinase was sharply increased from 61.3 to 93.8%. However, above 30 mg/mL, it did not increase. The inhibition effects of elastase and collagenase were increased with the extract concentration. Especially, when acetone extract concentration of A. sinicus Linne seed was increased from 25 to 200 μg/mL, the inhibition effect of elastase was increased from 60.2 to 97.5%. The inhibition effect of collagenase was increased from 35.0 to 99.0% when increased from 50 to 300 μg/mL. The indexes of pigment and coarseness were 28.56 MI and 18.45R-value, respectively, after 8 weeks of clinical trial using cream pack containing 0.2% of acetone extract of A. sinicus Linne seed. The indexes of elasticity and moisture were 64.5Ur/Uf and 55.2AU, respectively, after 8 weeks of clinical trial. These results demonstrate that acetone extract of A. sinicus Linne seed may be useful as a potential agent for functional cosmetics.     

海星多糖的提取分离与抗氧化活性研究

目的:从南海海星中提取多糖并研究其抗氧化活性。方法:采用碱提-酶解法提取海星多糖,并采用离子交换层析与凝胶过滤层析法进行纯化;采用醋酸纤维素薄膜电泳及凝胶过滤色谱法鉴定纯度;采用Fenton反应体系研究清除羟基自由基活性,采用邻苯三酚自氧化法研究清除超氧阴离子活性;采用H2O2损伤家兔红细胞模型研究其对生物膜的抗氧化保护作用。结果:海星多糖及阳性对照甘露醇、苯甲酸清除羟基自由基的半数有效浓度EC50分别为5.51 mg/mL、16.33 mg/mL、4.29 mg/mL;海星多糖及阳性对照维生素C清除超氧阴离子自由基的半数抑制浓度IC50分别为32.36μg/mL、18.32μg/mL;海星多糖对H2O2致红细胞损伤有良好的保护作用。结论:海星多糖具有较强的抗氧化活性。     

响应面优化淫羊藿抗氧化多酚超声提取工艺

以总多酚得率和DPPH自由基清除率为指标,采用响应面设计法优化淫羊藿抗氧化活性多酚超声提取工艺。结果表明以多酚得率为指标时,最佳工艺条件为：57％乙醇,料液比28 mL／g,在50℃下超声提取25 min,总多酚得率为34．58 mg／g;以DPPH自由基清除率为指标时,最佳工艺条件为：58％乙醇,料液比30 mL／g,在50℃下超声提取22 min, DPPH自由基清除率为88．4％。     

Assessment of Tamarindus indica Extracts for Antibacterial Activity

Ethanolic and aqueous (hot and cold) extracts of the fruit pulp, stem bark and leaves of Tamarindus indica were evaluated for antibacterial activity, in vitro, against 13 Gram negative and 5 Gram positive bacterial strains using agar well diffusion and macro broth dilution techniques, simultaneously. The fruit pulp extracts exhibited a wide spectrum of activity; the cold water extract against 95.5% of the test bacterial strains; and the hot water and ethanolic extracts against 90.9% and 86.4%, respectively. In contrast the cold water extract of the leaves and stem bark, each was active against 16.7%; while the ethanolic extract of each was active against 75% of the test strains. The minimum inhibitory concentrations (MIC) ranged from 7.81 mg/mL against Bacillus subtilis ATCC 6051 to 31.25 mg/mL against Escherichia coli ATCC 11775; and the minimum bactericidal concentration (MBC) ranged from 125 mg/mL against Pseudomonas aeruginosa ATCC 10145 to 250 mg/mL against Bacillus subtilis ATCC 6051.