双歧杆菌培养基的优化

针对双歧杆菌的营养需要,分别采用单因素试验和正交试验,优化培养基成分及用量。得出最优培养基(CPT)配比:大豆蛋白胨1.67%,酪蛋白胨0.83%,乳糖0.5%,酵母浸出粉0.5%,低聚糖0.7%,胡萝卜汁15%。最后测定双歧杆菌在最优培养基中的生长曲线,并同时测定pH和吸光值的变化,确定培养终止时间为12h,菌数可达2.18×109CFU/mL,且发酵培养基具有极显著的增菌效果(p<0.01)。     

长双歧杆菌发酵培养基的优化

目的对长双歧杆菌液态发酵培养基进行优化。方法以长双歧杆菌（Bifidobacteriumlongum）为发酵菌株,以MRS培养基为基础培养基,以发酵液活菌数为指标,通过单因素添加实验考察发酵培养基的碳源和氮源的种类,并验证优化后培养基的效果。结果优化后培养基的最适碳源为葡萄糖,最适氮源为酪蛋白胨、牛肉蛋白胨、水解乳蛋白,发酵液活菌数达到2．09×10^9CFU／mL,比原MRS培养基（1．22×10^9CFU／mL）提高了71．30％。结论优化后培养基优于原MRS基础培养基,可应用于长双歧杆菌的液态发酵。     

双歧因子的提取及其促双歧杆菌生长的初步观察

本文介绍了多种从猪胃粘蛋白及胡萝卜中提取双歧因子的方法。并用含双歧因子的培养基对四种双歧杆菌的生长进行了定性、定量观察,其结果显示了双歧因子是一种具有促双歧杆菌生长的活性因子,它可用于治疗某些疾病或作为保健食品及动物饲料添加剂,对促进人、动物体的健康及婴幼儿的正常发育具有重要生理意义。     

双歧因子对双歧杆菌增殖的影响

应用含有不同浓度的双歧因子(微维乐)的培养基对双歧杆菌进行了定性、定量观察。其结果表明,微维乐对双歧杆菌有明显的促进作用;在双歧杆菌制剂的生产过程中,添加一定量的微维乐,不仅可以提高双歧杆菌收率,而且还可以缩短菌种发酵时间。最佳添加量为1.5%,最佳发酵时间为1.5 h。     

培养基及培养工艺对双歧杆菌产量的影响

目的：对双歧杆菌生产培养基进行筛选,提高双歧杆菌的产量。方法：使用保蒲培养基,采用发酵罐培养工艺。结果：使用保蒲培养基较西红柿原汁培养基可使双歧杆菌的产量提高3.06-5.36倍。用保蒲培养基采用发酵罐培养工艺较立瓶静止培养工艺双歧杆菌的产量可提高4.91-54.8倍;发酵罐培养工艺较用西红柿原汁培养基、立瓶培养工艺产量提高17.33-154.29倍。结论：用保蒲培养基发酵罐培养可大大提高双歧杆菌的产量。     

双歧杆菌发酵番茄生产保健饮料

以新鲜的番茄为原料,加工成番茄汁后,采用双歧杆菌发酵生产制成保健饮料,通过单因素及正交实验确定最佳发酵条件为:菌种添加量为4%,发酵温度37℃,发酵时间10 h,原汁质量分数60%;辅料添加量:果胶0.15%,PGA0.1%,黄原胶0.1%,磷酸二氢钠0.05%;产品调配的最佳配方为:蜂蜜4%,蔗糖3%,水果香精2%     

双歧番茄醋的实验研究

目的以番茄为主要原料,对双歧杆菌和醋酸杆菌共同发酵研制双歧番茄醋的工艺进行研究。方法通过正交试验筛选最适工艺。结果双歧番茄醋的最终醋酸度为27 g/L,含双歧杆菌总菌为1.9×1011CFU/mL,5 d内双歧杆菌活菌为5.5×107CFU/mL。双歧番茄醋棕黄色,光泽度好,有成熟番茄香味,入口酸甜适中。结论双歧杆菌与醋酸杆菌在可以番茄汁中共生,此方法制备双歧番茄醋可行。     

响应面法优化两歧双歧杆菌发酵培养基

根据两歧双歧杆菌的营养需要和生长特性,采用响应面分析法对两歧双歧杆菌的培养基进行优化研究。先用Plackett-Burman设计法实验确定重要因素,再用最陡爬坡实验法确定因素水平,最后用响应面分析方法求得的最佳培养基配方为经优化的发酵培养基配方为:酪蛋白胨1.0%,大豆蛋白胨0.5%,酵母膏1.63%,半胱氨酸盐酸盐0.0076%,低聚果糖0.13%,葡萄糖0.5%,K2HPO4 0.2%。用此优化的发酵培养基培养两歧双歧杆菌,活菌数可高达7.8×10~9 cfu/ml。     

双歧杆菌及微生态制剂

自 Tissier于 1899首先发现双歧杆菌 (Bif idobacterrium)以来 ,双歧杆菌及其制品与人们的日常生活间的关系日趋紧密。已报道双歧杆菌属的 3 2个种 [1]栖居于人和动物 (牛、羊、兔、鼠、猪、鸡和蜜蜂等 )的肠道、反刍动物的瘤胃、人的齿缝和阴道等部位。其中除齿双歧杆菌可能是病原菌外 ,其他种尚无致病性的报道。近年 ,含有一定数目活菌的微生态制剂的研究取得了很大的进展 ,尤其是含有双歧杆菌的微生态制剂。据19 94年统计 ,国内约有 60多种含双歧杆菌的产品投入市场。在国外 ,含双歧杆菌的食品也十分流行 ,特别是在日本、欧洲和北美。据…     

两歧双歧杆菌86321生长特性的研究

目的研究两歧双歧杆菌86321的生长特性,为该菌生理功能研究和高效发酵剂的研制提供理论依据。方法通过生长曲线、产酸量、最适厌氧方式、最适pH、最适培养温度及最适接种量等一系列实验,对两歧双歧杆菌86321进行生长特性的研究。结果两歧双歧杆菌86321在BL培养基中培养时间可缩短至16 h,最高活菌数的lg值达到9.5;其最适厌氧方式为自然厌氧法或密封法,装液量视实际情况而定;在pH7.08.0生长良好,最适初始pH为8.0;在3742℃生长良好,最适温度为37℃;综合总菌量和生产成本,确定最适接种量为7%（v/v）。结论用BL培养基可以大大提高两歧双歧杆菌86321的产量。细菌产量的高低和发酵速度的快慢与菌种活力、厌氧方式、培养温度及pH等因素密切相关。     

Optimization of culture medium for growth of Haematococcus pluvialis

A central composite rotatable design was used to examine the effects of five components of the medium on the growth of Haematococcus pluvialis in batch culture. The medium components considered were: sodium acetate,potassium nitrate, major elements, trace elements and vitamins. Within the range of the concentrations tested, a moderate concentration of the major elements significantly enhanced algal growth, both in terms of specific growth rate and cell dry weight, whereas the vitamins had no significant effect. Based on the response surface contour plots and the results of numerical analyses, the optimal nutrient concentrations for growth in terms of specific growth rate were 0.51 g L^-1 sodium acetate, 0.25 g L^-1 potassium nitrate, 0.63 mL L^-1 of the major element stock solution and 0.2 mL L^-1 of the trace element stock solution. The optimal nutrient concentrations for biomass production were 1.64 g L^-1 sodium acetate, 0.37 g L^-1potassium nitrate, 2.52 mL L^-1 of the major element stock solution and 0.03 mL L^-1 of the trace element stock solution. This revised version was published online in August 2006 with corrections to the Cover Date.     

林可霉素生物合成培养基的优化

以花生粉和棉籽蛋白粉取代了原培养基中的黄豆饼粉,采用响应面法对林可霉素产生菌的发酵培养基进行了优化.首先通过单因素试验及正交实验确定替代氮源及其浓度,采用Plackett-Burman实验分析各因素的主效应,选出对响应值影响较大的3个因素,即花生粉、K2HPO4和玉米浆.对这些因素做爬坡实验,确定三个重要因素的中心点浓...     

An improved culture medium for mouse blastocysts

Summary Eagle's basal medium, modified to contain essential amino acids at the concentrations optimal for mouse blastocyst hatching, attachment, and outgrowth, supported in vitro development of the mouse blastocyst better than other tissue culture media tested. This medium was improved for growth and differentiation of the inner cell mass by doubling the concentration of amino acids and glucose and by adding uridine (10⁻⁵ M) and β-mercaptoethanol (10⁻⁵ M). In this improved medium nearly all blastocysts grown from the two-cell stage hatched and formed trophoblast outgrowths, and 62% developed into two-layer egg cylinders. This work was supported by the U.S. Department of Energy.     

拟干酪乳杆菌发酵L-乳酸合成培养基的优化

为开发一种适合于乳酸发酵过程代谢流分析(MFA)的合成培养基,以拟干酪乳杆菌Lactobacillus paracasei为对象,考察主要营养成分对其生长和乳酸合成的影响.在合成培养基的优化过程中,先确定了影响菌体生长和乳酸合成的主要营养物质及其浓度范围,针对葡萄糖、混合氛基酸、核苷类物质、维生素等生长因子、混合磷源、CaCO3六大类营养成分,使用正交试验法先后设计了六因素五水平和四因素三水平正交试验以及氨基酸梯度试验和氨基酸缺失试验,得到了最佳培养基组成(1L):葡萄糖80g、醋酸钠2g、吐温-80 1 mL、柠檬酸氢二铵1g、金属离子0.72g、混合氨基酸3.925g、核苷类物质0.15g、维生素等生长因子0.075g、混合磷源0g、CaC03 35g.以半合成培养基为对照,考察优化后的合成培养基对菌体生长和乳酸合成的影响.结果表明,菌体在合成培养基中的乳酸产量、产率均比半合成培养基中高.这些结果为L.paracasei的代谢流定量研究莫定了基础.     

Optimum medium for large-scale culture of Tetraselmis tetrathele

The prasinophyte Tetraselmis tetrathele is an alga commonly used as livefood for aquatic animal larvae. The alga is usually cultured in Guillard& Ryther medium (Guillard F) or a fertilizer enriched seawater mediumfor the large-scale culture of Nannochloropsis. However, Guillard F is toocomplicated to use for large-scale culture, and some fertilizers are impureand insoluble. A new enriched seawater medium for the large-scale culture ofT. tetrathele (ES-T.T.) was formulated by modifying the Guillard F medium.NaNO₃, NaH₂PO₄, Fe-EDTA andMnCl₂were selected as essential additives for the medium bysystematically removing each additive of Guillard F. Results from axenicculture experiments, using an artificial seawater medium, the requiredamount of these additives was estimated to be, 150 mg NaNO₃,10 mg NaH₂PO₄ · 2H₂0, 15 mgFe-EDTA and 360 µg MnCl₂ · 4H₂O,per liter of seawater. The productive rate of T. tetrathele in ES-T.T. washigher than in a fertilized medium in a 100 liter outdoor cultureexperiment. In 10 liter indoor culture experiments, no significantdifference was detected in production rates between ES-T.T. and Guillard F.Therefore, ES-T.T. is simple and effective to use as a large-scale culturemedium for T. tetrathele.     

Optimization of culture conditions for human corneal endothelial cells

Summary Long-term cultivation of human corneal endothelial cells (HCEC) was optimized with respect to different components of the culture system: 25 different nutrient media, different sera, 6 mitogens and various substrates were tested in their ability to influence clonal growth and morphology of HCEC. F99, a 1∶1 mixture of the two media M199 and Ham’s F12, was the most effective basal medium in promoting clonal growth of HCEC. Among various sera, human serum and fetal bovine serum showed optimal growth promoting activities in combination with F99, whereas newborn bovine serum (NBS) was by far superior for the development of a typically corneal endothelial morphology. Crude fibroblast growth factor (FGF), or alternatively endothelial cell growth supplement, was absolutely essential for clonal growth of HCEC at low serum concentrations, for example 5% NBS. Formation of a monolayer with a morphology similar to corneal endothelium in vivo was observed only on culture dishes coated with basal membrane components such as collagen type IV, laminin, or fibronectin. The most pronounced effect on morphologic appearance was obtained by culturing the cells on the extracellular matrix (ECM) produced by bovine corneal endothelial cells. Moreover, ECM could substitute for crude FGF in clonal growth assays.     

Development of a serum-free medium for the production of humanized antibody from chinese hamster ovary cells using a statistical design

Summary To develop serum-free (SF) media for the production of humanized antibody from recombinant Chinese hamster ovary (rCHO) cells, a statistical optimization approach based on a Plackett-Burman design was adopted. A basal medium was prepared by supplementing α-minimal essential medium (α-MEM) with Fe(NO₃)₃·9H₂O, CuCl₂, ZnSO₄·7H₂O, and Na₂SeO₃ which are generally contained in SF medium formulations. Insulin, transferrin, and ethanolamine were also supplemented to the basal medium to determine their optimal concentrations. From this statistical analysis, serine, phenylalanine, and tyrosine were identified as important determinants for cell growth. Also, putrescine, linoleic acid, and hydrocortisone were shown to be important for both cell growth and antibody production. The SF medium was formulated by supplementing the basal medium with components showing positive effects on cell growth and/or antibody production. Cell growth and antibody production in this SF medium were comparable to those in α-MEM supplemented with 5% dialyzed fetal bovine serum. Taken together, the results obtained here show that a Plackett-Burman design facilitates the development of SF media for rCHO cells aimed at producing a humanized antibody.     

A serum-free medium for hybridoma cell culture

The effects of several different substances, including insulin, transferrin, ethanolamine, selenite and butyrate on the growth of murine hybridoma 2F7 cells, which secrete monoclonal antibody against small cell lung cancer, were investigated, and a serum-free medium SFMI was formulated. The effects of taurine, spermidine, progesterone and adenine on the cell growth were tested further on the basis of the medium SFMI, and a modified serum-free medium SFM II was established. On the basis of medium SFM II, the substitution tests of ferric citrate for transferrin were carried out, and it was found that transferrin could be replaced. The experiments suggested that the formulated serum-free medium was suitable for 2F7 cell growth and monoclonal antibody secretion, and thus facilitated subsequent purification of monoclonal antibody.Abbreviations BSA bovine serum albumin - CS calf serum - DMEM Dulbecco's modified Eagle's medium - ELISA enzyme-linked immunosorbant assay - McAb monoclonal antibody - PEG polyethylene glycol - SFM serum-free medium     

A new culture medium for human skin epithelial cells

Summary A new culture medium, NCTC 168, has been designed for human skin epithelial cells. This medium formulation was developed, by combining and testing at various concentrations, components of media NCTC 135 and 163, since a 1∶1 mixture of these two media with 10% horse serum supplement was found to promote epithelial cell outgrowth from human skin explants. The buffer system in NCTC 168 maintains the pH of the medium between 7.0 and 7.2. In contrast to other media tested, NCTC 168 with 10% horse serum is capable of initiating and sustaining larger epithelial cell outgrowths. Explants in serum-supplemented NCTC 168 in the absence of feeder cells reproducibly yield confluent epithelial cell sheets apparently free of fibroblasts after only 19 to 28 days as compared with 5 weeks or longer for the other media tested. NCTC 168 also supports passage of human epithelial cells to the sixth subculture generation without feeder cells. Electron microscopy has shown the presence of desmosomes and tonofilaments in the passaged cells indicating the epithelial nature of the cells. The addition of epithelial growth factor, hydrocortisone and insulin at 5 ng per ml, 4 μg per ml and 5 μg per ml, respectively did not appreciably enhance the growth of the epithelial cells.