几个啤酒酵母菌株的性能比较

对近期引进的四个啤酒酵母菌株进行了形态，生理特征及发酵性能的比较，并进行了实验室小型发酵中，以期为大生产中酵母菌株的选择提供一定的参考。     

基于问题的案例教学在发酵工艺原理教学中的应用

基于问题的案例教学将以问题为主线的分析讨论与真实直观的案例相结合,既可调动学生学习的兴趣和主动性,又可提高其分析问题、解决问题的能力。本文从案例的选择、问题的设计、教学的实施、效果分析等方面探讨了其在发酵工艺原理教学中的应用,以期为本学科的教学改革提供参考。     

种子染菌成因探析及防治

种子染菌严重影响发酵生产,会增加生产成本。文章分别从物品灭菌、种子制备环境、无菌操作和设备等几个方面来阐述维生素C菌种在制备过程中的种子带菌原因,操作人员在工作中的注意事项,以及误判为种子带菌等情况,并用实例加以分析说明,提出防治措施,在菌种生产中对避免和防止杂茵污染具有一定指导意义。     

枯草芽孢杆菌Bs-07液态发酵提高黑木耳多糖抗凝血功能(英文)

为了提高黑木耳多糖的抗凝血功能,应用微生物发酵技术转化黑木耳多糖得到抗凝血活性更强的黑木耳多糖衍生物.研究了黑木耳多糖转化的最佳发酵条件,比较了未转化和转化后的黑木耳多糖的体外抗凝血功能.通过响应面和正交试验得出最佳转化条件:将浓度4.0 mg/m L的黑木耳酸性多糖AAP3溶液与对羟基苯甲酸充分混合(体积比为40∶1),调p H至6.0,接种枯草芽孢杆菌Bs-07,在温度为35℃,旋转摇床转速为120 r/min的条件下,发酵48 h,转化率达40%以上.检测转化后黑木耳多糖衍生物APTT,PT和TT的数据结果显示,转化后黑木耳多糖衍生物体外抗凝血功能得到了明显提高.     

发酵法生产天然β-胡萝卜素的优化方案

对利用三孢布拉霉发酵法生产天然β-胡萝卜素的方法中的种子培养基和发酵培养基进行了优化．选用淀粉培养基,用乙酸乙酯为溶剂发酵,淀粉含量为2．3％,pH值为6．6时,发酵单位提高94．21％．     

微生物发酵法生产利巴韦林的研究进展

利巴韦林是高效的广谱抗病毒药物。文章对它的理化性质和应用,合成原理以及生产方式进行了概述。重点则介绍了发酵法合成利巴韦林的原理、现状以及对发酵过程优化的一些研究。最后对发酵法合成利巴韦林的前景做了展望。     

不同发酵类型的茶叶原花青素含量的比较分析

采用超声波法从不同发酵类型的茶叶中提取原花青素化合物,通过正交实验确定了最佳提取条件,并建立了原花青素的光谱分析方法．方法的回收率为99．15％～104．50％,相对标准偏差小于1．27％．结果表明,3种不同发酵类型的茶叶中原花青素的含量情况是：不发酵的绿茶含量最多,其次是半发酵青茶,全发酵红茶含量最少．     

Rumen fermentation and acetogen population changes in response to an exogenous acetogen TWA4 strain and Saccharomyces cerevisiae fermentation product

The presence of yeast cells could stimulate hydrogen utilization of acetogens and enhance acetogenesis. To understand the roles of acetogens in rumen fermentation, an in vitro rumen fermentation experiment was conducted with addition of acetogen strain (TWA4) and/or Saccharomyces cerevisiae fermentation product (XP). A 2×2 factorial design with two levels of TWA4 (0 or 2×10⁷ cells/ml) and XP (0 or 2 g/L) was performed. Volatile fatty acids (VFAs) were increased (P<0.05) in XP and TWA4XP, while methane was increased only in TWA4XP (P<0.05). The increase rate of microorganisms with formyltetrahydrofolate synthetase, especially acetogens, was higher than that of methanogens under all treatments. Lachnospiraceae was predominant in all acetogen communities, but without close acetyl-CoA synthase (ACS) amino acid sequences from cultured isolates. Low-Acetitomaculum ruminis-like ACS was predominant in all acetogen communities, while four unique phylotypes in XP treatment were all amino acid identified low-Eubacterium limosum-like acetogens. It differs to XP treatment that more low-A. ruminis-like and less low-E. limosum-like sequences were identified in TWA4 and TWA4XP treatments. Enhancing acetogenesis by supplementation with an acetogen strain and/or yeast cells may be an approach to mitigate methane, by targeting proper acetogens such as uncultured low-E. limosum-like acetogens.     

酿酒酵母产孢条件及核倍性分析

通过优化得出了耐热酿酒酵母HU－TY－1及其亲株LK的最佳产孢条件。利用随机孢子分析获得了HU－TY－1的单倍体Hs系列和LK的单倍体Ls系列，并对它们进行了发酵效率的测定，发现Hs系列在40℃条件下发酵效率好于Ls系列，体现了耐高温特性。此外对由HU－TY－1及其单倍体Hs125自身融全构建的二倍体与四倍体菌株进行发酵效率的分析显示，随着核倍性的增加，菌株的耐热性有增加的趋势。     

Designing asynchronous online fermentation science materials including using a home fermented foods project to engage online learners

The number of online courses offered by universities in America continues to increase. Due to limited direct interactions with students, these courses can struggle to promote student engagement. Food science is uniquely situated for implementation of hands‐on project‐based learning opportunities since basic experiments can be performed in a kitchen with minimal supplies and equipment. The purpose of this teaching and learning tip is to share materials designed for an asynchronous online course, instructional fermentation vignettes, and the Home Fermented Foods Project assignment, which tasks students with creating two fermented foods with two accompanying documents explaining the science of each employed steps. Students are engaged with the projects while connecting the lecture material to familiar products that they create such as sauerkraut, yogurt, and bread. Overall, based on student evaluations and our interactions with the students, our implementation of this project has been positive. Downloadable handouts containing assignment details are available as Supporting Information.