Preparation the Key Intermediate of Angiotensin‐Converting Enzyme (ACE) Inhibitors: High Enantioselective Production of Ethyl (R)‐2‐Hydroxy‐4‐Phenylbutyrate with Candida boidinii CIOC21

Forty microorganisms belonging to different taxonomical groups were used to catalyze the enantioselective reduction of ethyl 2‐oxophenylbutyrate to afford the corresponding ethyl 2‐hydroxy‐4‐phenylbutyrate. Several microorganisms led to over 99% ee of ethyl (S)‐2‐hydroxy‐4‐phenylbutyrate. Especially, we firstly found that the Candida boidinii CIOC21 could be effectively used for the enantioselective preparation the ethyl (R)‐2‐hydroxy‐4‐phenylbutyrate in pure aqueous medium with 99% ee, a key intermediate in the production of angiotensin‐converting enzyme (ACE) inhibitors.     

Evaluation of the fermentative potential of Candida zemplinina yeasts for craft beer fermentation

The fermentative potential of Candida zemplinina Y.01667 and Y.01670 was evaluated to explore the potential use of these yeasts for craft beer fermentations. Fermentation experiments were carried out at different temperatures and soluble solid concentrations, using synthetic media with glucose syrup as a sugar source and with a laboratory malt wort plus different adjuncts. Results showed that both strains fermented well at 14 °C and had improved fermentative activity at 20 °C. The fermentative kinetics of C. zemplinina Y.01667 and Y.01670 were not affected when experiments at higher concentrations of soluble solids were conducted. Furthermore, C. zemplinina strains had better growth, higher viable cells counts, less free amino nitrogen consumption, lower sedimentation rates and slighter changes in pH values, when compared with results of the lager beer yeast Saccharomyces cerevisiae S‐23 in the synthetic medium tested. Fermentations in a malt wort with different adjuncts indicated that C. zemplinina Y.01670 could possibly be used as a yeast in craft beer production. Copyright © 2016 The Institute of Brewing & Distilling     

无溶剂体系中毕赤酵母表面展示CALB全细胞催化合成肉桂醇酯

利用表面展示南极假丝酵母脂肪酶B(Candida antarctica lipase B,CALB)的毕赤酵母细胞(Pp-CALB)为全细胞催化剂,以不同脂肪酸作为酰基供体,在无溶剂体系中和肉桂醇发生酯化反应合成肉桂醇酯。探究了Pp-CALB对于不同酰基供体的选择性,并且对反应温度、摇床转速、酶加量、底物摩尔比、酶的水活度和反应体系等一系列影响酶催化反应的因素进行了优化,建立了无溶剂体系中肉桂醇酯的酶法合成工艺。结果表明,在底物摩尔比为2:1,摇床转速为120 r/min,反应温度为50℃的条件下,添加初始水活度为0.53的Pp-CALB 0.05 g,反应3h,肉桂醇的酯化率可达81.34%,在最适反应条件下,使用Pp-CALB连续反应8次后,肉桂醇的酯化率仍然能达到70.00%以上,具有较好的操作稳定性。     

真空冷冻干燥橄榄假丝酵母的制备及其对苹果青霉病的防治

选用真空冷冻干燥技术,糖醇类试剂包括海藻糖、蔗糖、乳糖、山梨糖醇,抗氧化类试剂谷氨酸钠,以及赋形剂包括脱脂奶粉和β-环糊精三大类试剂作为保护剂,通过保护剂的单因素筛选试验、正交试验得到真空冷冻干燥橄榄假丝酵母的最优保护剂配方为海藻糖添加量15%、谷氨酸钠添加量2%和脱脂奶粉添加量10%,所得酵母存活率为69.7%。此外,通过比较冻干橄榄假丝酵母和新鲜橄榄假丝酵母对苹果果实青霉病的发病率和病斑直径的研究,并测定冻干橄榄假丝酵母和新鲜橄榄假丝酵母接种处理后酵母在苹果果实伤口处的生长动态,以期制备性能良好的生物防治试剂。     

扁平云假丝酵母与酿酒酵母混合发酵对葡萄酒乙醇含量及香气的影响

为降低葡萄酒中的乙醇含量,采用不同接种方式（同时接种和顺序接种）在两个温度下（13?℃和23?℃）进行扁平云假丝酵母（Candida humilis）与酿酒酵母（Saccharomyces cerevisiae）的发酵实验。结果表明：23 ℃时混合发酵除高产甘油外,还有效降低了乙醇含量,其中与S. cerevisiae单独发酵相比,顺序接种可降低乙醇体积分数约2.59%,降醇幅度达到17.56%。在香气方面,混合发酵能产生较高含量的酯类物质,其中顺序接种最为明显,如乙酯类物质总量和乙酸乙酯含量分别增加了18.30%和16.03%,丁酸乙酯含量提高了2.77?倍,明显增加了花香和果香;13?℃时,混合发酵显著提高了β-大马士酮的含量,其中同时接种发酵增加26.19%。结果表明C. humilis与S. cerevisiae进行混合发酵具有较好的降醇效果,可以为葡萄酒的降醇研究提供一种新的解决方法。     

Emodin,a natural inhibitor of protein kinase CK2, suppresses growth,hyphal development,and biofilm formation of Candida albicans

Emodin (1,3,8‐trihydroxy‐6‐methyl‐anthraquinone) is a natural secondary plant product, originally isolated from the rhizomes of Rheum palmatum. Many reports show its diuretic, vasorelaxant, antibacterial, antiviral, anti‐ulcerogenic, immunosuppressive, hepatoprotective, anti‐inflammatory and anticancer potential. Emodin is a pleiotropic molecule capable of interacting with several major molecular targets, e.g. NF‐κB, AKT/mTOR and STAT3. The compound can also act as an inhibitor of some protein kinases, with special affinity to protein kinase CK2. The aim of the presented report was to evaluate antifungal properties of emodin and its activity towards CK2 isolated from Candida cells. Our studies revealed that the compound suppressed growth of the cells of reference strains as well as clinical Candida strains, with minimal inhibitory concentration and minimal fungicidal concentration values between 12.5 and 200 μg/mL. Moreover, at a low concentration, the compound was able to effectively stop hyphal formation, thus showing a distinct antivirulent potential. Interestingly, we showed that emodin added to Candida culture inhibited the phosphorylation of many cellular proteins, presumably owing to the inhibition of protein kinase CK2. Notably, the enzyme isolated from the Candida cells was susceptible to emodin with IC₅₀ of 2.8 μg/mL. Indeed, our computational modelling revealed that emodin was able to occupy the ATP‐binding pocket of CK2. Copyright © 2017 John Wiley & Sons, Ltd.     

双菌混合发酵丢糟生产微生物油脂的研究

探索利用假丝酵母和皮状丝孢酵母混合发酵丢糟生产微生物油脂的最佳工艺条件.在对假丝酵母和皮状丝孢进行驯化培养的基础上,设定假丝酵母和皮状丝孢酵母的比例、接种量、培养温度、培养时间为4个因素,进行L9(34)正交试验,通过测定油脂含量,获得油脂生产的最佳工艺条件.研究结果表明,双菌发酵丢糟生产微生物油脂的最佳工艺条件:假丝酵母和皮状丝孢酵母的比例为1:1,接种量为9％,培养温度为32℃,培养时间为4d,在该条件下测得每1000g丢糟发酵物中油脂含量为21.14g.     

Artists of the Floating World: SANNA,Niedermayr and the Construction of Atmosphere

Hugh Campbell expands upon the mutually collaborative spatial qualities evoked in the photographic works of Walter Niedermayr and the architecture of Kazuyo Sejima and Ryue Nishizawa of Tokyo-based practice SANAA. Describing their relation as forming a ‘thickened presence’, he alludes to a particular atmosphere reliant on an ambiguity of scale, detail and discernible proximity that serves to liberate the architecture and the photographs from mere documentation whereby instead they figure as transparent recordings of spatial intentions. Copyright © 2008 John Wiley & Sons, Ltd.     

南极假丝酵母脂肪酶B在黑曲霉中的分泌表达及其硅藻土固定化应用

为提高南极假丝酵母脂肪酶B（Candida antarctica lipase B,CALB）表达量,根据黑曲霉（Aspergillus niger）密码子偏好性设计合成CALB基因,以PnaII/tpi为启动子构建CALB表达载体并转化到黑曲霉HL-1中表达,摇瓶发酵120 h后上清液中重组CALB活力为171 U/mL。研究重组CALB的酶学性质,最适反应温度和pH值分别为50 ℃和8.0,在pH 6.0～9.0和45 ℃以下具有较高的稳定性,10 mmol/L Cu2＋、Zn2＋和0.1 g/100 mL十二烷基硫酸钠强烈抑制酶活力,而1 mmol/L Ca2＋、0.1 g/100 mL山梨醇对酶活力具有非常明显的激活作用。此外,以硅藻土为载体固定CALB,固定化酶活力为187 U/g。将制备的硅藻土-CALB固定化酶用于生物合成己酸乙酯,经反应条件优化后在无溶剂体系中己酸乙酯产率达91%。     

醇类物质诱导培养改善近平滑假丝酵母(Candida parapsilosis)去消旋转化能力

采用近平滑假丝酵母Candida parapsilosis全细胞去消旋转化外消旋苯基乙二醇(PED)制备S-苯基乙二醇. 主要研究了在菌体培养阶段添加底物醇类和酮类对菌体生长及菌体产酶的影响. 研究发现添加乙醇可以促进细胞生长,提高细胞中脱氢酶活力,从而改善菌体立体选择性转化能力. 通过在菌体培养至对数生长期时添加0.1%乙醇,菌体量增长10%,相对酶活提高30%,采用相同浓度菌体转化105 mmol/L (R, S)-苯基乙二醇时,产物(S)-苯基乙二醇的对映过量值从90%提高至99%,产率从87.3%提高至92.4%.