五倍子鞣质提取物对白假丝酵母的抗菌活性研究

目的 研究五倍子鞣质提取物对白假丝酵母的体外抗茵活性.方法 通过超声波提取五倍子有效成分鞣质,福林-酚比色法检测鞣质含量,采用微量稀释法检测五倍子鞣质提取物对白假丝酵母的最低抑菌浓度(MIC)和最低杀菌浓度(MFC),以最低抑茵浓度药物作用白假丝酵母6、12、24h,通过普通光学显微镜直接观察白假丝酵母形态结构的变化,并用吖啶橙/溴化乙锭染色,通过荧光显微镜观察白假丝酵母的死亡方式.结果 五倍子鞣质提取物对白假丝酵母的最低抑菌浓度为10.76 mg/mL,最低杀菌浓度为21.52mg/mL;五倍子鞣质提取物可导致白假丝酵母细胞变形,形态结构改变,最终导致其死亡;同时抑制细胞发芽和假菌丝的形成.结论 五倍子鞣质提取物对白假丝酵母有抑制和杀灭作用.     

百蕊草亲水性化学成分研究

目的 对百蕊草中亲水性化学成分进行研究。方法 采用硅胶柱色谱、SephadexLH-20凝胶柱色谱等分离手段,对百蕊草水提取物经AB-8大孔树脂吸附,50%乙醇洗脱的亲水性组分（TT50）进行分离纯化,应用核磁共振波谱分析、结合文献报道鉴定化合物结构。结果 从TT50中分离纯化得到6个化合物,分别鉴定为：山奈酚（1）,紫云英苷（2）,山奈酚-3,7-二-O-β-D-吡喃葡萄糖苷（3）,山奈酚-3-O-L-吡喃鼠李糖基（1→2）-β-D-吡喃葡萄糖苷（4）,山奈酚-3-O-L-吡喃鼠李糖基（1→2）-［6-O-乙酰基］-β-D-吡喃葡萄糖苷（5）,芸香苷（6）。结论 TT50中主要成分为以山奈酚为母核的黄酮苷类化合物,化合物4、5为首次从百蕊草中分离得到。     

用HPLC法测定百蕊草中3个黄酮苷的含量

目的 建立HPLC法同时测定百蕊草中3个黄酮苷类化合物的含量。方法 色谱柱为DIKMA C₁₈柱（250 mm×4.6 mm,5 μm）,流动相为乙腈-水（21∶79,V/V）,用冰醋酸调节pH至4.61,流速：1.0 ml/min,柱温：25℃,检测波长：346 nm。结果3个黄酮苷化合物山奈酚-3-O-L-吡喃鼠李糖基（1→2）-β-D-吡喃葡萄糖苷（百蕊草素Ⅰ）、山奈酚-3-O-β-D-吡喃葡萄糖苷（紫云英苷）、山奈酚-3-O-L-吡喃鼠李糖基（1→2）-[6-O-乙酰基]-β-D-吡喃葡萄糖苷（6''-乙酰氧基百蕊草素Ⅰ）的进样浓度分别在125~200、2.5~40、5.0~80 μg/ml范围内线性关系良好（r=0.999 9）,平均加样回收率分别为101.63%、99.82%和102.02%,RSD分别为1.72%、2.34%和1.94%（n=6）。结论 该方法准确,稳定性、重现性好,可作为百蕊草药材及制剂的质控方法。     

吩嗪类衍生物的抗真菌活性研究

目的 研究吩嗪类衍生物的抗真菌活性。方法 利用微量液基稀释法考察吩嗪类衍生物的体外抗真菌活性;利用棋盘式微量稀释法检测吩嗪类衍生物与氟康唑合用对常见临床耐药菌的抗真菌活性;在菌丝诱导条件下考察吩嗪衍生物对白念珠菌菌丝形成的抑制效果。结果 吩嗪类衍生物单用对临床常见条件致病真菌白念珠菌没有明显抗真菌活性;吩嗪衍生物-17与氟康唑合用有显著抗白念珠菌活性;吩嗪衍生物-17与氟康唑合用可以明显抑制白念珠菌菌丝生长。结论 筛选获得了与氟康唑合用具有抗真菌活性的吩嗪类衍生物-17,为抗真菌药物研发和克服真菌耐药提供了新思路。     

小春花药材质量标准研究

目的 制定并考察小春花药材质量标准,为进一步开发小春花药材提供基础。方法 采用紫外-可见分光光度法建立小春花中总黄酮的含量测定方法;采用HPLC同时测定小春花药材中槲皮素和山奈酚的含量。结果 建立小春花总黄酮的测定方法,槲皮素为在30.23~181.40 μg·mL^-1呈良好线性关系,R²=0.998 4;确定药材中槲皮素、山奈酚的含量测定方法,槲皮素在2.64~21.12μg·mL^-1呈良好的线性关系,R²=0.999 8,山奈酚在2.00~16.00μg·mL^-1呈良好的线性关系,R²=0.999 9;小春花总黄酮以槲皮素计不得<0.2‰,山奈酚计不得<0.6‰。结论 本研究对小春花药材进行质量控制,提升并建立了新的小春花药材质量标准。     

HPLC同时测定三叶青中5种黄酮类成分的含量

目的 建立HPLC同时测定三叶青中5个黄酮类化合物芦丁、异槲皮苷、山奈酚-3-O-芸香糖苷、槲皮素和山奈酚的含量。方法 Agilent ZORBAX SB-C₁₈色谱柱（250 mm×4.6 mm,5 μm）;流动相为乙腈-0.2%磷酸溶液,梯度洗脱,流速为1.0 mL·min^-1,检测波长为360 nm,柱温为35℃。结果 芦丁、异槲皮苷、山奈酚-3-O-芸香糖苷、槲皮素和山奈酚分别在0.087 8~0.878 μg、0.069 6~0.696 μg、0.162 9~1.629 μg、0.002 7~0.027 μg、0.007 23~0.072 3 μg内与峰面积呈良好的线性关系,r ≥ 0.999 7;平均加样回收率分别为97.44%,96.88%,97.00%,96.42%,96.24%。结论 该方法简便、高效,可作为三叶青的质量控制提供参考。     

氨基丁酸联合卡泊芬净抗白色假丝酵母菌生物被膜协同作用研究

目的探讨氨基丁酸联合卡泊芬净抗白色假丝酵母菌生物被膜的协同作用。方法利用白色假丝酵母菌标准菌株SC5314,采用生物被膜形成实验,分为空白对照组、氨基丁酸单用组、卡泊芬净单用组、氨基丁酸联合卡泊芬净组,对比各组生物被膜形成情况。采用XTT还原法测定氨基丁酸、卡泊芬净单用以及氨基丁酸联合卡泊芬净对成熟生物被膜细胞代谢活性的抑制作用。采用YNB培养基菌丝形成实验,考察氨基丁酸与卡泊芬净合用是否具有协同抑制菌丝形成的作用。结果卡泊芬净0.1μg·mL-1联合氨基丁酸0.1μmol·L-1对白色假丝酵母菌SC5314生物被膜的形成具有显著的抑制作用。此外,XTT还原法测定氨基丁酸6.25μmol·L-1联合卡泊芬净0.1μg·mL-1时降低被膜细胞代谢活性的效率能够达到约15%。采用YNB培养基形成菌丝,氨基丁酸6.25μmol·L-1联合卡泊芬净0.1μg·mL-1对白色假丝酵母菌SC5314菌丝形成能力有显著的抑制作用。结论氨基丁酸联合卡泊芬净表现出显著的体外协同抗白色假丝酵母菌标准菌株SC5314生物被膜作用。     

复方氟康唑凝胶对耐氟康唑假丝酵母菌的抗菌效果研究

目的 验证复方氟康唑凝胶对耐氟康唑假丝酵母菌的抗菌效果。方法 选用琼脂扩散法,比较复方氟康唑凝胶与氟康唑凝胶对耐氟康唑假丝酵母菌的体外抑菌效果;通过感染耐氟康唑假丝酵母菌大鼠治疗试验,比较复方氟康唑凝胶与氟康唑凝胶治疗效果。结果 复方氟康唑凝胶抑菌圈直径(18.55±0.03)mm（n=20）,氟康唑凝胶抑菌圈直径(7.12±0.01)mm（n=20）,差异具有统计学意义（P<0.05）;复方氟康唑凝胶治疗感染耐氟康唑假丝酵母菌大鼠15d的转阴率为80%,氟康唑凝胶为40%,差异具有统计学意义（P<0.05,n=15）;复方氟康唑凝胶抑制阴道灌洗液炎性细胞因子水平能力、减轻病变损伤程度明显高于氟康唑凝胶（P<0.05,n=15）。结论 复方氟康唑凝胶对耐氟康唑假丝酵母菌的抗菌效果肯定,较氟康唑凝胶具有优势。     

苦参总碱对无乳链球菌、粪肠球菌和白假丝酵母菌增殖影响的体外观察研究

目的:研究苦参总碱对女性下生殖道几种常见致病菌(无乳链球菌、粪肠球菌和白假丝酵母菌)体外增殖的影响以及对白假丝酵母菌生物膜形成的影响。方法:体外培养无乳链球菌、粪肠球菌和白假丝酵母菌,通过琼脂板稀释法制备菌板,检测不同浓度苦参总碱对无乳链球菌、粪肠球菌和白假丝酵母菌的最小抑菌浓度(MIC);通过结晶紫染色法和共聚焦显微成像检测苦参总碱对白假丝酵母菌生物膜形成的影响;通过扫描电镜成像法观察苦参总碱对生物膜形成和菌落形态的影响。结果:苦参总碱对无乳链球菌、粪肠球菌和白假丝酵母菌的MIC分别为16,32,32 mg·mL^-1。苦参总碱质量浓度1 mg·mL^-1时对白假丝酵母菌生物膜的形成有明显的抑制作用(P<0.05),且抑制程度呈浓度依赖性,浓度越高,对生物膜的抑制作用越明显。同时,电镜下亦可见随着苦参总碱浓度的升高,白假丝酵母菌不仅生物膜形成受到抑制,且菌丝形成受到阻断,菌落中菌丝变短、菌丝间连接变疏松。结论:苦参总碱(16,32,32 mg·mL^-1)对无乳链球菌、粪肠球菌和白假丝酵母菌的增殖均有抑制作用,且能抑制...     

锦灯笼的化学成分研究

从锦灯笼[Physalis alkekengi L. var. franchetii （Mast.） Makino]中提取物中分离出12个化合物,通过波谱方法和理化性质分别鉴定为：酸浆苦素B（1）,酸浆苦素A（2）,4,7-didehydroneophyalin B（3）,（Z）-9,10,11-三羟基-12-十八碳烯酸（4）,酸浆苦素F（5）山奈酚-3-O-β-D-葡萄糖苷（6）,3′,4′-二甲基槲皮素（7）,山奈酚-3,7-二氧-α-L-双鼠李糖苷（8）,十五碳酸（9）,二十四碳酸（10）,3,4-二羟基苯乙醇（11）,齐墩果酸（12）。化合物6～11为首次从该属植物中分出,化合物5为首次从该种植物中分出。     

Effect of filamentation and mode of growth on antifungal susceptibility of Candida albicans

Biofilm formation involving profuse hyphal growth is a major characteristic of Candida spp. and confers higher antifungal resistance than its planktonic mode of growth. We investigated the antifungal susceptibility of Candida albicans and its hyphal mutants (Δefg1/efg1, Δcph1/cph1 and ΔΔcph1/cph1 efg1/efg1) to commonly used antifungals during planktonic, adhesion and biofilm modes of growth. The minimum inhibitory concentration (MIC) of each antifungal agent was determined for a lower inoculum (1 × 10³ cells/mL) and higher inoculum (1 × 10⁷ cells/mL) of planktonic Candida. Furthermore, MICs of C. albicans biofilms and adhesion modes of growth were determined with a standard XTT assay. Candida albicans in adhesion and biofilm modes of growth, but not in planktonic mode, were resistant to all five antifungal agents tested. Although Δefg1/efg1 and ΔΔcph1/cph1 efg1/efg1 mutants formed less biofilm than wild-type C. albicans SC5314, they were similarly resistant to caspofungin. However, these mutants were more sensitive to amphotericin B and nystatin than the wild-type. Adhesion per se confers increased resistance to antifungal agents, which is further pronounced in the biofilm mode of Candida. Filamentation does not appear to be a major determinant of the antifungal resistance in Candida biofilms.     

Transcriptional response of Candida albicans biofilms following exposure to 2-amino-nonyl-6-methoxyltetralin muriate

Aim:

To identify changes in the gene expression profile of Candida albicans (C albicans) biofilms following exposed to 2-amino-nonyl-6-methoxyl-tetralin muriate(10b) and clarify the mechanism of 10b against C albicans biofilms.

Methods:

Anti-biofilm activity of 10b was assessed by tetrazolium (XTT) reduction assay and the action mechanism against biofilms was investigated by cDNA microarray analysis and real-time RT-PCR assay.

Results:

Ten differentially expressed genes were directly linked to biofilm formation and filamentous or hyphal growth (eg, NRG1, ECE1 and CSA1). Decreased gene expression was involved in glycolysis (eg, HXK2 and PFK1) and antioxidant defense (eg, SOD5), while increased gene expression was associated with enzymes that specifically hydrolyzed β-1,3 glucan (XOG1), and with lipid, fatty acid and sterol metabolism (eg, SLD1, ERG6 and ERG2). Functional analysis indicated that addition of anti-oxidant ascorbic acid reduced inhibitory efficiency of 10b on mature biofilm.

Conclusion:

Inhibition of 10b on biofilm formation possibly depends on impairing the ability of C albicans to change its morphology via altering the expression of biofilm formation genes. Mitochondrial aerobic respiration shift and endogenous ROS augmentation might be a major contribution to reduce mature biofilm metabolic activity. The data may be useful for the development of new strategies to reduce the incidence of device-associated infections.     

Novel Carboline Derivatives as Potent Antifungal Lead Compounds: Design,Synthesis, and Biological Evaluation

相似文献   

Antifungal activity of ribavirin used alone or in combination with fluconazole against Candida albicans is mediated by reduced virulence

The incidence of fungal infections has increased continuously in recent years, and drug resistance, especially resistance to fluconazole (FLC), has emerged. To overcome this challenge, research on the antifungal activities of non-antifungal agents has gained more attention. In this study, we determined the anti-Candida activity of ribavirin (RBV), an antiviral drug commonly used in the clinic, and found that RBV displayed potent antifungal activity when used alone or in combination with FLC in vitro and in vivo. In vitro, the MIC₈₀ values of RBV were 2–4 µg/mL for FLC-susceptible Candida albicans and 8 µg/mL for FLC-resistant C. albicans. When RBV at a dose of 1 µg/mL was combined with FLC, significant synergistic effects were exhibited against FLC-resistant C. albicans, and the MICs of FLC decreased from >512 µg/mL to 0.25–1 µg/mL. Synergism was also exhibited against C. albicans biofilms. In vivo, RBV plus FLC significantly improved the survival of infected Galleria mellonella larvae compared with the FLC-treated group over a 4-day period and attenuated the damage of FLC-resistant C. albicans to G. mellonella larvae tissue. Furthermore, mechanistic studies indicated that the antifungal effects of RBV used alone or in combination with FLC might be associated with inhibition of biofilm formation, reduced extracellular phospholipase activity and inhibition of hyphal growth, but is not related to promotion of FLC uptake and inhibition of FLC efflux. These results provide a promising direction for overcoming drug resistance and for expanding the clinical application of existing drugs.     

2014—2017年解放军总医院海南分院真菌分布及耐药性分析

目的 了解2014—2017年解放军总医院海南分院真菌的分布和耐药特点,为促进抗真菌药的合理应用、有效减缓真菌耐药提供参考。方法 提取解放军总医院海南分院2014年1月—2017年12月临床真菌分离和药敏相关数据,分析真菌的分布特征及其对常用抗真菌药的耐药率和变化趋势。结果 共纳入1 048份阳性真菌样本,呼吸道标本占41.89%,60岁以上患者（61.45%）和重症医学科（25.48%）分布比例最高;共分离出1 329株真菌,白色念珠菌、念珠菌属、热带念珠菌分别占24.53%、15.80%、13.69%。各种念珠菌对两性霉素B和5-氟胞嘧啶的敏感率基本保持在90%以上;热带念珠菌对伊曲康唑耐药率最高,达10%～20%,对氟康唑和伏立康唑的耐药率亦高于两性霉素B和5-氟胞嘧啶;白色念珠菌对伊曲康唑和伏立康唑的耐药率呈逐年快速上升趋势。结论 白色念珠菌和热带念珠菌感染应慎用唑类抗真菌药;两性霉素B和5-氟胞嘧啶是念珠菌感染的有效选择。     

基于D-SERS法表征两性霉素B对白色念珠菌抑制作用的研究

目的 建立动态表面增强拉曼光谱法（D-SERS）快速表征两性霉素B （AMB）对白色念珠菌的抑制作用。方法 采用D-SERS法,选用敏感的白色念珠菌分别与不同浓度的AMB相互作用,在不同的作用时间下,通过考察拉曼位移在656 cm^-1和729 cm^-1处的峰强比和药物浓度之间的关系,分析AMB对白色念珠菌拉曼光谱的影响。结果 在一定药物浓度和作用时间下,峰强比与AMB浓度呈负相关,可用于描述AMB对白色念珠菌的抑制作用,且药物浓度低于其最小抑菌浓度。结论 该方法简便、快捷,实现了AMB对白色念珠菌的快速表征,同时为表征更多药物-病原体相互作用提供了更简单、快速的检测方法。     

The Effect of Cetylpyridinium Chloride (CPC) on the Cell Surface Hydrophobicity and Adherence of Candida albicansto Human Buccal Epithelial Cells in Vitro

Purpose. This study examined the effects of cetylpyridinium chloride (CPC) on cell surface hydrophobicity (CSH) and adherence of blastospores of Candida albicans(MEN strain) to human buccal epithelial cells (EEC) in vitro. Methods. The effect of CPC treatment of either C. albicans blastospores or BEC on their subsequent adherence was determined using ³⁵SO₄ labelled blastospores in association with a Percoll gradient. The effects of CPC treatment of blastospores on their CSH was determined using Hydrophobic Interaction Chromatography. Results. Treatment of exponential and stationary phase blastospores with CPC (50 µg mL^–1) for 0.5–30 minutes, or with CPC (0.5–50 µg mL^–1) for 15 minutes resulted in significant reductions in both blastospore CSH and adherence to BEC in vitro. No correlation was apparent (r < 0.8) between reduced CSH and reduced blastospore adherence following treatment with CPC (0.5–50 µg mL^–1). Significantly reduced adherence of C. albicans (stationary or exponential growth phases) to human EEC was also observed following treatment of BEC with CPC (50 µg mL^–1) for 0.5–30 minutes or with CPC (0.5–50 µg mL^–1) for 15 minutes. Antiadherence effects were observed at both sub and super-minimum inhibitory concentrations of CPC. Conclusions. It is suggested that, whilst the ability of CPC to reduce the CSH of C. albicans may contribute to its reduced adherence to human BEC in vitro, reduced CSH is only one of several possible factors that contribute to the observed antiadherence effects.     

丁香酚对压疮致病菌金黄色葡萄球菌及其耐药菌的抑菌作用及机制

目的 明确丁香酚对压疮致病菌金黄色葡萄球菌Staphylococcus aureus的体外抑菌作用及机制。方法 采用微量肉汤稀释法和和生长曲线确定丁香酚对金黄色葡萄球菌的抑菌活性；通过碱性磷酸酶（AKP）活性、细菌核酸蛋白泄漏的检测，细菌超微结构的扫描和透射电镜观察以及菌体对碘化丙啶（PI）和N-菲酰-次巯基-L-丙氨酸（NPN）的摄取来探讨丁香酚处理后金黄色葡萄球菌细胞膜的通透性和完整性；以结晶紫染色法和实时荧光定量PCR法研究丁香酚对菌体生物被膜（BF）生成、成熟以及菌体黏附、侵袭相关毒力因子表达水平的影响。结果 丁香酚对金黄色葡萄球菌标准菌和耐甲氧西林金葡菌（MRSA）的最低抑菌浓度（MIC）分别为0.25、0.125 mg/mL。丁香酚处理后可以提高细菌培养液中核酸、蛋白浓度及AKP的活性；菌体出现皱缩和破裂，菌体内膜和外膜中分别出现PI和NPN荧光，菌体结构破坏和荧光强度与丁香酚浓度呈正相关。丁香酚能够抑制金黄色葡萄球菌菌株BF的生成，且对成熟BF具有明显清除作用，显著降低BF生成相关基因agrA、sarA、cidA和icaA及黏附因子clfA、clfB、fnbA和fnbB的基因表达水平；与标准菌株相比，丁香酚对MRSA的作用更明显。结论 丁香酚对金黄色葡萄球菌标准菌株和耐药菌株均具有显著抗菌作用，可破坏菌体细胞结构，改变细胞膜通透性和完整性，抑制BF的生成，并对成熟BF具有清除作用，抑制细菌BF及黏附侵袭相关毒力因子的转录和表达，可能是艾灸促进压疮创面修复的机制之一。     

Pericoterpenoid A,a new bioactive cadinane-type sesquiterpene from Periconia sp.

Pericoterpenoid A (1), a new cadinane-type sesquiterpene, was isolated from an endolichenic fungal strain Periconia sp. (No. 19-4-2-1). Its structure was characterized by analyzing the spectroscopic data (IR, MS, 1D- and 2D-NMR). The antimicrobial activity against Escherichia coli, Staphylococcus aureus, Aspergillus niger, and Candida albicans was evaluated. Pericoterpenoid A showed moderate antimicrobial activity against A. niger and weak activity against C. albicans. This is the first report of the presence of cadinane-type sesquiterpene in Periconia sp.