Optimization of process parameters for reduction of gossypol levels in cottonseed meal by Candida tropicalis ZD-3 during solid substrate fermentation.

The objective of this work is to optimize the process parameters for detoxification of gossypol in cottonseed meal (CSM) by Candida tropicalis ZD-3 during solid substrate fermentation (SSF). The maximum detoxification efficiency of gossypol was achieved by employing the substrate, which consists of 70% of CSM, 20% of corn flour and 10% of wheat bran. The optimum fermentation conditions for gossypol detoxification are incubation period of 48h, incubation temperature at 30 degrees Celsius, inoculum level 5% v/w, moisture content of solid substrate 50% and pH in nature. Adding minerals solution to CSM substrate benefit fermentation detoxification.     

阴道用制剂控制菌白色假丝酵母菌检验方法的研究

目的建立适合阴道用制剂控制菌白色假丝酵母菌检查方法,为药典收载阴道用制剂品种提供微生物限度检验方法。方法按《中国药典》2005年版一部要求,将5个菌株制备成新鲜菌液,分别用沙氏葡萄糖琼脂、10g.L-1聚山梨酯80-玉米粉琼脂2种培养基,3个培养温度进行培养,记录菌落大小及形态鉴别,并将结果进行比较。结果白色假丝酵母菌在35～37℃沙氏葡萄糖琼脂培养基生长良好。10g.L-1聚山梨酯80-玉米粉琼脂培养基中可见假菌丝及厚膜孢子。血清培养基37℃培养1～3h可见芽管。结论检验方法可行,建议收载于2010年版《中国药典》中。     

耐两性霉素B的近平滑与热带假丝酵母菌的体外诱导及耐药分子机制研究

目的：体外诱导近平滑假丝酵母菌（ CP）、热带假丝酵母菌（ CT）对两性霉素B（ AMB）的耐药株,检测其中的耐药基因表达情况。方法 AMB体外构建耐药株,用实时荧光定量PCR法检测耐药基因的表达水平。结果 CP、CT 野生株经体外 AMB 浓度递增法诱导后,形成耐药株最低抑菌浓度（ MIC,≥8μg? mL－1）;CYP51A、CYP51B、CDR1、CDR2、MDR1及MDR2基因在野生株中低水平表达,在耐药株中表达水平明显升高,差别有统计学意义（ P ＜0．05）;CYP51A、CYP51B、CDR1、CDR2、MDR1及MDR2的表达量在CPAMB耐药株中分别是其野生株的136．92,16．33,2．07,14．84,4．07,2．38倍;在CT AMB耐药株中分别是其野生株的8．83,2．98,3．00,2．40,2．30,3．57倍。结论 CP、CT对AMB耐药与CYP51A、CYP51B、CDR1、CDR2、MDR1及MDR2基因过度表达有关。     

氮唑类抗真菌药物药效构象及其与酶活性位点对接

目的：研究氮唑类抗真菌药物与其受体蛋白活性位点相互作用机理。方法：用随机构象搜寻和分子动力学模拟退火法确定１５个４种不同类型的氮唑类抗真菌药物最低能量构象;用活性类似物法限定药物分子药效基团之间的距离,搜寻到各化合物药效构象;将各化合物药效构象对接到白色念珠菌羊毛甾醇１４α去甲基化酶活性位点中。结果：４种结构类型的氮唑类药物在酶活性位点中有相似的对接位置;真菌和哺乳动物的活性位点结构特异性的残基分布在Ｆ螺旋Ｃ端、β６１和β６２区中;氮唑类抗真菌药物共同的卤代芳环结构落入相同的疏水空穴中,其中Ｙ１３２的侧链羟苯基结构可与抑制剂卤代芳环形成电子迁移复合物。结论：对接结果与已知ＳＡＲ分析结论相符,阐明了氮唑类药物与活性位点的氨基酸残基作用方式,探讨结构选择性药物的结构需求。     

Antifungal Activity of Gallic Acid In Vitro and In Vivo

Gallic acid (GA) is a polyphenol natural compound found in many medicinal plant species, including pomegranate rind (Punica granatum L.), and has been shown to have antiinflammatory and antibacterial properties. Pomegranate rind is used to treat bacterial and fungal pathogens in Uyghur and other systems of traditional medicine, but, surprisingly, the effects of GA on antifungal activity have not yet been reported. In this study, we aimed to investigate the inhibitory effects of GA on fungal strains both in vitro and in vivo. The minimal inhibitory concentration (MIC) was determined by the NCCLS (M38‐A and M27‐A2) standard method in vitro, and GA was found to have a broad spectrum of antifungal activity, with MICs for all the tested dermatophyte strains between 43.75 and 83.33 μg/mL. Gallic acid was also active against three Candida strains, with MICs between 12.5 and 100.0 μg/mL. The most sensitive Candida species was Candida albicans (MIC = 12.5 μg/mL), and the most sensitive filamentous species was Trichophyton rubrum (MIC = 43.75 μg/mL), which was comparable in potency to the control, fluconazole. The mechanism of action was investigated for inhibition of ergosterol biosynthesis using an HPLC‐based assay and an enzyme linked immunosorbent assay. Gallic acid reduced the activity of sterol 14α‐demethylase P450 (CYP51) and squalene epoxidase in the T. rubrum membrane, respectively. In vivo model demonstrated that intraperitoneal injection administration of GA (80 mg/kg d) significantly enhanced the cure rate in a mice infection model of systemic fungal infection. Overall, our results confirm the antifungal effects of GA and suggest a mechanism of action, suggesting that GA has the potential to be developed further as a natural antifungal agent for clinical use. Copyright © 2017 John Wiley & Sons, Ltd.     

Antifungal activity of the plant Dodonaea viscosa var. angustifolia on Candida albicans from HIV-infected patients

THE AIM OF THIS STUDY: was to determine the minimum inhibitory concentration (MIC) and the time taken by Dodonaea viscosa var. angustifolia (PLE) a South African medicinal plant, chlorhexidine gluconate (CHX) and triclosan (TRN) to kill Candida albicans. 41 strains of Candida albicans were investigated, 20 from HIV-positive patients, 20 from HIV-negative subjects and Candida albicans ATCC 90028. The MICs of an acetone extract of PLE, CHX and TRN were measured using a microtitre double dilution technique, and the time taken to kill 99.5% of the strains was determined. The MICs of PLE, CHX and TRN were 6.25-25, 0.008-0.16 and 0.0022-0.009 mg/ml, respectively. PLE killed all the test strains within 30s and CHX 40% of the isolates from HIV-positive patients and 20% of strains from HIV-negative subjects in 1 min. During the same time TRN killed 55% and 35% of isolates from HIV-positive and HIV-negative patients. Dodonaea viscosa var. angustifolia has antifungal properties and is more effective than commercially available mouthrinses.     

新型抗白念珠菌药物的作用靶点

随着氮唑类药物广泛应用,白念珠菌耐药现象快速发展,已出现药物间交叉耐药,对临床治疗带来严重威胁.近年来相继提出了许多抗白念珠菌药物作用的新靶点并成功开发出一些活性强大,疗效确切的抗真菌药,如以真菌细胞壁为靶点开发出棘白菌素类药物卡泊芬净、米卡芬净等,该类药物主要抑制β-葡聚糖合成酶,体外对氟康唑耐药的念珠菌属及真菌生物被膜表现出强大的抗菌活性,又由于β-葡聚糖合成酶在哺乳类动物细胞内不存在,故具有高效低毒的临床效果,是一极具前途的新型抗真菌药;以真菌细胞膜为靶点开发出Histatin类药物,虽然作用机制目前还不完全明了,但其作用不同于临床常用的多烯类和氮唑类,并已经发现Histatin5对两性霉素B和氮唑类耐药的念珠菌有效,并且对非白念珠菌如光滑念珠菌、克柔氏念株菌、隐球菌等也有杀灭作用;通过对植物药物的研究发现黄连素和丁香罗勒(Ocimum gratissimum L.)具有较强大的抗真菌活性,其中黄连素提取物小檗碱对24-MST抑制作用强大,并对菌丝生长形式抑制作用强于酵母生长形式.增强白念珠菌对药物敏感性的新方法包括改变细胞膜成分、改变某些基因、利用光灭活作用、使用抗菌药增敏剂以及抗真菌药物的联合使用等.本文就近年来开发的新型抗真菌药以及提出的抗白念珠菌药物作用新靶点进行综述.     

双歧杆菌脂磷壁酸对深部白色念珠菌感染小鼠细胞免疫的影响

目的：观察双歧杆菌脂磷壁酸（BLTA）对深部白色念珠菌感染小鼠细胞免疫功能的影响。方法通过尾静脉注射白色念珠菌建立免疫低下小鼠深部白色念珠菌感染模型,观察BLTA处理对小鼠胸腺指数、脾脏指数、脾淋巴细胞增殖活性、NK细胞杀伤活性及血清细胞因子水平的影响。结果免疫低下小鼠深部感染白色念珠菌后,小鼠胸腺指数、脾脏指数和脾脏淋巴细胞增殖活性轻度下降（P＞0．05）,NK细胞杀伤活性明显下降（P＜0．05）,IL‐2、IL‐4和INF‐γ水平轻微升高（P＞0．05）,IL‐10水平明显升高（P＜0．05）;BLTA处理后,小鼠胸腺指数、脾脏指数、脾淋巴细胞增殖活性和NK细胞杀伤活性明显升高（P＜0．01）,血清IL‐2和IN F‐γ水平明显升高（ P＜0．05）,IL‐4变化不大,IL‐10明显降低（ P＜0．01）。结论 BL T A可改善免疫低下小鼠的免疫功能状态,恢复甚至增强深部感染念珠菌后受到抑制的细胞免疫应答。     

白色念珠菌CDR基因表达与氟康唑体外药敏试验的关系研究

目的调查白色念珠菌临床株对氟康唑的耐药情况,研究白色念珠菌临床耐药基因的表达与氟康唑耐药之间的关系。方法采用M27-A2微量肉汤稀释法,对某院微生物实验室2010年分离保存的221株来自就诊患者的痰、中断尿、粪便和咽拭子的白色念珠菌进行氟康唑MIC值测定。以白色念珠菌18S RNA为内参照,采用RT-PCR技术观察比较耐药株和敏感株组在不同氟康唑浓度下CDR1和CDR2基因的转录水平。结果 221株白色念珠菌中,有57.47%（127株）对氟康唑敏感,10.86%（24株）剂量依赖敏感,31.67%（70株）耐药。不同药物浓度作用下,耐药株组CDR1和CDR2的表达量相对要高于敏感株组（P〈0.05）。结论白色念珠球菌对氟康唑耐药率较高,耐药株组CDR1和CDR2表达量高于敏感株组。     

真菌性阴道炎假丝酵母菌属临床分布及药敏分析

目的探讨真菌性阴道炎假丝酵母菌属临床分布和药敏试验结果。方法回顾性分析1628例阴道炎患者的临床资料,进行真菌培养,药敏试验采用K-B纸片法。结果分离出假丝酵母菌属8种133株,阳性率为8.17%,以白色假丝酵母菌为主占64.66%。假丝酵母菌对特比萘芬的耐药率较高为43.61%、氟康唑为27.82%、伊曲霉唑为21.05%、制霉菌素为3.76%和两性霉素为6.77%。结论真菌性阴道炎感染以白色假丝酵母菌为主,并呈现出多药耐药特点,应根据药敏结果选择合理的抗真菌药物。