短乳杆菌49蛋白提取及酶解条件优化

为了最大程度上获取短乳杆菌49（Lactobacillus brevis 49）的蛋白质信息，分别优化了蛋白质的提取条件与酶解条件。用正交实验法考察细胞破碎方法、蛋白酶种类、酶解时间、酶添加量4个因素对 L. brevis 49的胞内蛋白提取方法以及酶解方法的影响，以质谱中检测到的蛋白质数目为参考指标进行优化；同时对培养基氮源进行优化，并分别选用TCA沉淀法、冷丙酮沉淀法、平衡酚 丙酮法和超滤法提取发酵液中的胞外蛋白。结果表明：L. brevis 49胞内蛋白最佳的提取破壁方法为超声破碎法，最佳水解酶为糜蛋白酶和胰蛋白酶共同作用，最佳的酶与蛋白质量比为 1∶50，最佳酶解时间为12 h，获得胞内蛋白数目527个。获得L. brevis 49胞外蛋白的最佳培养基为0.6%酵母浸粉做单一氮源的MRS培养基，最佳提取方法为三氯乙酸（TCA）法，可获得44个含信号肽蛋白。该方法有望为啤酒的安全检测提供参考。     

小麦胚乳醇溶蛋白反相高效液相色谱(RP-HPLC)分离方法的建立

通过对比试验研究洗脱时间、柱温、流速、洗脱梯度等对反相高效液相色谱法的影响,确立适宜小麦胚乳醇溶蛋白(Gliadin)反相高效液相色谱法(RP-HPLC)分离的最佳实验方法为:在1.0mL/min的流速、60℃的柱温条件下对上样醇溶蛋白进行洗脱、洗脱梯度为流动相B的体积比在55min内由21%升至48%(V/V),最后通过210nm紫外光检测洗脱组分的吸收值。     

研制蜂胶冻干粉的最佳工艺研究

本文探讨了以粗蜂胶为原料,研制蜂胶冻干粉的的工艺。结果表明:蜂胶冻干粉的工艺流程为粗蜂胶─→醇溶法提取─→赋形─→冻干─→冻干粉。最佳工艺条件为:(1)醇溶法提取蜂胶的最佳条件:固液比:1:25,乙醇溶液浓度75%,提取温度80℃,提取时间1.5h。(2)赋形剂为22%甘露醇,赋形的最佳条件为:22%甘露醇与4%的蜂胶乙醇溶液按76:24的比例混合。(3)冻干条件:预冻温度-74℃,预冻时间2小时,抽真空时间24小时,升温干燥20℃,升温干燥30分钟,冷阱温度为-52℃。在此条件下生产的蜂胶冻干粉的溶解度为87%,水分含量为0.93,总黄酮含量为0.49%。     

丹参提取工艺研究

通过对传统的乙醇回流提取法和醇浸水提取法的试验仪器和试剂以及色谱条件的介绍,以丹酚酸B和丹参酮ⅡA为指标成分,优化了最佳提取工艺,为丹参制剂的前处理生产工艺提供了实验依据。     

研制蜂胶冻干粉的最佳工艺研究

本文探讨了以粗蜂胶为原料,研制蜂胶冻干粉的的工艺。结果表明：蜂胶冻干粉的工艺流程为粗蜂胶—→醇溶法提取—→赋形—→冻干—→冻干粉。最佳工艺条件为：（1）醇溶法提取蜂胶的最佳条件：固液比：1：25,乙醇溶液浓度75％,提取温度80℃,提取时间1．5h。（2）赋形剂为22％甘露醇,赋形的最佳条件为：22％甘露醇与4％的蜂胶乙醇溶液按76：24的比例混合。（3）冻干条件：预冻温度-74℃,预冻时间2小时,抽真空时间24小时,升温干燥20℃,升温干燥30分钟,冷阱温度为-52℃。在此条件下生产的蜂胶冻干粉的溶解度为87％,水分含量为0．93,总黄酮含量为0．49％。     

免疫PSO算法在啤酒配方优化中的应用研究

针对PSO算法在搜索过程中粒子容易失去多样性而陷入局部最优的缺陷,本文提出了一种免疫的PSO算法.该算法借助免疫接种与免疫选择两个免疫操作来优化PSO算法,从而达到优化搜索的目的,有助于提高其收敛速度,并将该算法应用于啤酒配方优化问题中.应用结果表明:使用免疫PSO算法对啤酒糖化配方进行优化,可以在较少的搜索步数内得到良好的优化效果,优化后所得配方的原料总成本有明显降低,具有工业应用价值.     

银杏叶中聚戊烯醇酯的CO2超临界流体提取及高效液相色谱分析

采用自制的CO2 超临界流体萃取系统提取了银杏叶中聚戊烯醇酯 ,考察了温度、压力、流速及时间等因素对提取效率的影响 ,确定了最佳的超临界流体提取条件。实验结果表明 ,CO2 超临界流体提取银杏叶中聚戊烯醇酯的最佳压力、温度、流速、时间分别为 2 5MPa、6 5℃、8mL/min、6h。采用本方法萃取的提取物经过硅胶色谱柱纯化及高效液相色谱分析 ,与溶剂提取法相比较 ,提取效率比较好     

不同方法提取侧柏叶中挥发性成分的气相色谱-质谱分析

采用气相色谱-质谱法(GC/MS)分析酶提取法(CE)、同时蒸馏萃取法(SDE)和水蒸气蒸馏-萃取法(DSE)三种方法提取侧柏叶挥发性成分。结果表明:三种方法提取侧柏叶挥发油的化学成分均有差异。酶提取法提取侧柏叶挥发油鉴定出32种化合物，主要成分为雪松烯，占挥发油总量的41.25%；同时蒸馏-萃取法提取侧柏叶挥发油鉴定出29种化合物，主要成分为雪松醇，占挥发油总量的39.06%；水蒸气蒸馏 萃取法提取侧柏叶挥发油鉴定出32种化合物，主要成分为雪松醇，占挥发油总量的31.43%。     

双四杆机构的运动分析及其优化

双四杆机构因其数学模型复杂,其速度和加速度曲线一直是研究的难点。以啤酒装箱机为例,探讨了啤酒装箱机双四杆机构的运动分析及其优化问题。将数学建模的专用软件Mathematica引入到啤酒装箱机双四杆机构的运动分析中,得到了速度与加速度特性曲线,并在此基础上进一步对双四杆机构进行优化。最后用参数化T-FLEX CAD软件对优化结果的运动轨迹进行仿真验证,获得了令人满意的效果。     

基于SimOpt的链段设计仿真优化研究

链段是啤酒生产线设计中需要考虑的重要因素,它直接与影响啤酒生产线性能指标的缓冲容量和缓冲时间参数紧密相关。链段设计本质上是一种组合优化问题,但由于生产线动静特性的影响,不能建立精确的生产线数学分析模型,传统设计方法只能给出留有较大冗余的解。本文研究应用仿真优化方法设计啤酒生产线并开发出基于虚拟仿真环境的制造系统仿真优化系统S imOpt,在实际应用中具有非常好的效果。     

Mass spectrometry in the proteome analysis of mature cereal kernels

In the last decade, the improved performance and versatility of the mass spectrometers together with the increasing availability of gene and genomic sequence database, led the mass spectrometry to become an indispensable tool for either protein and proteome analyses in cereals. Mass spectrometric works on prolamins have rapidly evolved from the determination of the molecular masses of proteins to the proteomic approaches aimed to a large‐scale protein identification and study of functional and regulatory aspects of proteins. Mass spectrometry coupled with electrophoresis, chromatographic methods, and bioinformatics tools is currently making significant contributions to a better knowledge of the composition and structure of the cereal proteins and their structure–function relationships. Results obtained using mass spectrometry, including characterization of prolamins, investigation of the gluten toxicity for coeliac patients, identification of proteins responsible of cereal allergies, determination of the protein pattern and its modification under environmental or stress effects, investigation of genetically modified varieties by proteomic approaches, are summarized here, to illustrate current trends, analytical troubles and challenges, and suggest possible future perspectives. © 2011 Wiley Periodicals, Inc. Mass Spec Rev 31:448–465, 2012     

Scanning probe microscopy studies of cereal seed storage protein structures

Scanning probe microscopes (SPMs) share a number of common features which give the techniques advantages over conventional light and electron microscopy. First, high resolution, up to the atomic level, is possible in certain cases, and second, they are nondestructive, requiring no staining or coating and the images can be obtained in the hydrated state or under water. Scanning probe microscopes, particularly scanning tunnelling microscopes (STM) and atomic force microscopes (AFM), have been used to study food-related systems, ranging from relatively large structures such as starch granules to the organisation of secondary structures in proteins and the interaction of proteins. The seed storage proteins (gluten) of wheat are responsible for the viscous and elastic properties of wheat doughs that allow them to be used for a wide range of different food products. Using AFM and STM, images of individual and groups of proteins have been obtained in both the dry and hydrated states. The ability to work in liquid environments allows the conformation of proteins to be determined under conditions approaching “native.” The AFM and STM have been used to image both gliadins and glutenins and to study their aggregative behaviour in relation to gluten and dough systems.     

SIEMENS变频器和PLC在硅胶自动添加调速系统中的应用

提高和稳定啤酒在保质期内的质量，关键因素是准确控制硅胶添加量和硅胶与啤酒的反应时间。文章叙述了硅胶自动添加调速系统的组成、原理，介绍了一种采用Siemens的MM42~变频器和PLC组成的变频调速系统来控制硅胶自动添加的方法。     

解吸附-电喷雾离子化质谱方法快速检测啤酒中的甲基乙二醛

A desorption electrospray ionization mass spectrometry(DESI-MS) method was developed to determine methylglyoxal(MG) present in beers. This method utilized 1,2-diamino-4,5-dimethoxybenzene to convert MG to 6,7-dimethoxy-2-methylquinoxaline, and then determined the derivative by DESI-MS. 1×10^－5 mol•L^－1 MG in water and 5×10－5 mol•L^－1 MG in Yan Jing beer can be determined using this method. This time-saving method may provide a way for high-throughput analysis of MG in beverages.     

啤酒糖化过程的自动控制

啤酒糖化是啤酒生产的重要环节。本文介绍实现啤酒糖化过程自动控制的系统配置;对糖化过程的3个主要工序：糊化糖化、过滤和煮沸,根据对象特性提出不同的控制方案控制其工艺参数,取得了很好的精度和 稳定性;采用结构化方法实现流程的自由组态,提高了糖化生产过程的自动化水平。     

Analysis and quantification of the secretory products of the subcommissural organ by use of monoclonal antibodies

Bovine Reissner's fiber (RF) glycoproteins were used as antigen for the production of polyclonal and monoclonal antibodies (Mabs). We also produced Mabs against intracellular secretory glycoproteins of the bovine subcommissural organ (SCO). These Mabs were used for immunodetection of secretory proteins in situ (structural and ultrastructural immunocytochemistry), in blots, and in solutions. Three different antigen-mediated ELISA were designed to evaluate the affinity of the Mabs, to study the nature of the epitopes, and for competition test among Mabs. Two double antibody sandwich ELISA were designed to detect and quantify soluble secretory materials in different samples, to study coexistence of epitopes, and to elucidate whether epitopes for Mabs are repeated or not in the RF-glycoproteins. Twenty-three Mabs recognizing the bovine RF- and SCO-glycoproteins in solutions (ELISA) as well as in tissue sections, were obtained. Nineteen of these Mabs also recognized the pig SCO, 11 the rabbit SCO, 6 the dog SCO, and 5 the rat SCO. None of the Mabs recognized the SCO of non-mammalian species. The different types of ELISA demonstrated that: (1) the epitopes reside in the proteinaceous moiety of the secretion, (2) they coexist in the same molecular forms and, with few exceptions, they did not overlap, (3) they were not repeated in the secretory molecule(s). Three Mabs were used for immunoblotting of RF; one of them revealed the same band pattern as that shown by an anti-RF serum. It is concluded that all Mabs raised in our laboratory are directed against non-repeated sequences of RF-glycoproteins that have not been conserved in vertebrate phylogeny.     

Interaction of maize zein with wheat gluten in composite dough and bread as determined by confocal laser scanning microscopy

Protein body-free maize zein, when mixed at 35 degrees C (above its glass transition temperature range), significantly (p < 0.01) improved the rheological and leavening properties of sorghum-wheat composite flour dough, resulting in improved loaf volume. Confocal laser scanning microscopy was used to observe the structure of zein fibrils and the interaction between zein and gluten proteins in the composite dough and bread systems. Autofluorescence and immunolocalization techniques were used to locate gluten and zein, respectively. Optical sections were collected every 0.4 microm through the samples and digitally processed to produce reconstructed three-dimensional images. Results showed that zein fibrils form an outer layer that intermittently coats the gluten networks, thereby strengthening them. This type of microstructure is able to withstand the pressure exerted by gas cell expansion during yeast fermentation to increase loaf volume.     

A combined additive manufacturing and micro-syringe deposition technique for realization of bio-ceramic structures with micro-scale channels

This article presents a novel rapid layered manufacturing approach based on a combined additive manufacturing (AM) process and a UV-based micro-syringe deposition (μSD) technique to be used in the fabrication of bio-ceramic structures with controlled micro-sized channels for bone and osteochondral tissue regeneration. In the proposed rapid manufacturing method, micro-scale sacrificial photopolymer networks are integrated within the manufactured part by depositing the photopolymer on selected bio-ceramic powder layers using an injection system. This AM–μSD method along with a post-processing protocol can potentially overcome current limitations of traditional powder-based AM approaches that are restricted in terms of complexity of internal architecture and feature size. For bone or osteochondral repair applications, the material system composed of the bio-ceramic and sacrificial photopolymer, along with the post-processing protocol, must ensure that the final implants are free from manufacturing residuals that could trigger an immune response post-implantation. In this study, calcium polyphosphate bio-ceramic was used as the substrate material based on prior art, polyvinyl alcohol solution was used as the powder binding agent, and ethoxylated (10 bisphenol A diacrylate) photopolymer solution was used as the sacrificial photopolymer element. Material characterization suggests that the proposed material system along with heat treatment protocol is suitable for the targeted applications where micro-scale channels within the implant are produced by AM–μSD.     

Villosiclava virens infects specifically rice and barley stamen filaments due to the unique host cell walls

Rice false smut, caused by the fungal pathogen Villosiclava virens, is one of the most important rice diseases in the world. Previous studies reported that the pathogen has less number of cell wall‐degraded genes and attacks dominantly rice stamen filaments and extends intercellularly. To reveal why the fungus infects plant stamen filaments, inoculation test on barley was carried out with the similar protocol to rice. The experimental results showed that the fungus could penetrate quickly into barley stamen filaments and extends both intracellularly and intercellularly, usually resulting in severe damage of the stamen filament tissues. It also attacked young barley lodicules and grew intercellularly by chance. The light microscopic observations found that the epidermal and cortex cells in barley stamen filaments arranged loosely with very thick cell walls and large cell gaps. Cellulose microfibrils in barley stamen filament cell walls arranged very sparsely so that the cell walls looked like transparent. The cell walls were very soft and flexible, and often folded. However, V. virens extended dominantly in the noncellulose regions and seemed never to degrade microfibrils in barley and rice cell walls. This suggested that the unique structures of rice and barley stamen filaments should be fit for their function of elongation in anthesis, and also endow with the susceptibility to the fungus, V. virens.