新工艺降低维生素C生产成本

美国Genencor国际公司和伊士曼化学品有限公司将于近日把一种维生素C生产新工艺工业化。该工艺利用基因工程改造过的细菌来发酵制取维生素C。用这种细菌把从谷物中得到的葡萄糖直接发酵成2-酮基-L-葡萄酸(2-KLG),而后者正是生产维生素C的重要中间产物。这一技术比传统维生素C生产工艺少了四个加工环节     

异维生素C钠工艺通过技术鉴定

由江苏省连云港市酿化厂开发成功的异维生素C钠生产工艺,最近在连云港通过了技术鉴定。 该厂在异维生素C钠小试成果的基础上,以60m3发酵罐的生产规模进行了发酵、控制及精制等三方面的工艺改进研究。扩大研究取得发酵平均产钙盐165mg/ml,转化率108％,     

VC二步发酵高糖流加工艺的研究

利用从生产中选育得到的耐高糖菌株,通过在线的检测数据,应用改进的高浓度山梨糖流加控制工艺,考察了初始山梨糖浓度、底物浓度、流加阶段pH等对维生素C二步发酵的影响,确定了适宜的控制工艺,提高了发酵水平及设备利用率.     

维生素C磷酸酯衍生物的制备及其在化妆品中的应用

维生素C磷酸酯克服了维生素C易被氧化的缺点并且在化妆品中应用广泛。本文阐述了国内外研究现状,总结了化学合成和生物发酵制备维生素C磷酸酯衍生物的方法,介绍了它们在化妆品中的应用情况。指出中国应加快研发维生素C磷酸酯衍生物及其它衍生物。     

维生素B12发酵工艺进展

综述了维生素B12(VB12)发酵工艺路线、菌种选育、工艺优化等方面的研究进展,展望了VB12发酵工艺发展前景。     

维生素C发酵一步工艺优化研究

针对目前维生素C（VC）发酵过程中一步发酵生产进行工艺优化探讨,从pH值、种后溶氧、山梨醇投醇浓度等关键生长条件入手,达到缩短发酵周期,提高产糖速率的效果。结果表明：一步菌种发酵过程最适pH值为4.8～6.0,发酵周期与种后溶氧成线性关系,投醇浓度控制在30%以下产糖速率最快。     

维生素C发酵过程中氧的供需规律的研究及放大依据的探讨

在12l、3.4m~3以及50m~3发酵罐中研究了通气和搅拌对维生素C发酵过程的影响,得到: 1.维生素C发酵液的流变学性质以及其他一些物理性质与水相近,并且在整个发酵期间变化不大。 2.对12l和3.4m~3发酵罐中维生素C发酵过程中氧的供需情况进行了研究,得到了在稳定时期2一酮基—L—古龙酸的生成速率(GPR)与氧消耗速率(r)之间的关系式。 3.在3.4m~3发酵罐中得到的最适溶解氧(D.O.)和体积氧传递系数(K_Lα)的范围与在12l发酵罐中得到的数值基本一致,并和在50m~3发酵罐中所测的数值相近。 4.在12l和3.4m~3发酵罐中分别得到K_Lα与操作变量的关联式。     

高校化学工程学报主办院校研究生学位论文题录

论文题目(带*者为博士论文)Topics of Thesis(*Ph.D.Dissertation)日期Date学生姓名Student导师姓名Advisor天津大学Tianjin University新型高速栓剂灌装设备系统温度场的研究2004-08李文祥谭蔚3-氨基-1H-1,2,4-三唑的合成与生产2004-08王旭陈立功维生素C发酵工艺的研究2004-08耿海义赵学明古龙酸酯转工艺研究2004-08唐清海马沛生维生素C生产中过滤介质选用的研究2004-08付秀涧谭蔚离子交换树脂连续式移动床提取VC过程研究2004-08李玉波元英进维生素C钠盐结晶工艺优化2004-08李立强尹秋响大孔树脂法回收粗粉结晶母液中的洛线他汀2004…     

维生素C钠结晶粒度的生产控制

研究了在维生素C钠生产工艺中对其粒度影响的几个因素,最终确定了维生素C钠结晶工艺的条件。     

C群和W_(135)群脑膜炎球菌发酵工艺的优化

目的优化C群和W135群脑膜炎球菌的发酵工艺,提高荚膜多糖产量。方法在5L发酵罐中,通过调整溶氧(DO)、pH值、培养温度、葡萄糖补料速率等参数,了解C群和W135群脑膜炎球菌在发酵过程中的代谢规律,优化发酵工艺,并将C群脑膜炎球菌在100L发酵罐中放大发酵。结果在发酵过程中,DO在20%～40%范围内对多糖合成无明显影响;在pH6.6左右,培养温度37℃,有利于多糖合成;发酵中间补加葡萄糖可增加多糖合成,低速补糖较高速补糖更有利于多糖合成。C群脑膜炎球菌在100L罐中放大发酵,多糖产量可达5L罐水平。结论通过参数优化,确定了C群和W135群脑膜炎球菌的最佳发酵工艺。     

维生素C一步发酵糖醪处理方式的研究

研究了VC一步发酵终点糖醪在未经处理、过滤除菌及经过不同温度处理后对VC二步发酵指标的影响,结果显示处理温度在100℃以内时,一步发酵糖醪中L-山梨糖破坏程度相对较小,不会对二步发酵收率及周期产生负面影响,与过滤除菌相比,低温灭菌在发酵罐内进行,减少了操作和对二步发酵的影响。     

麦角固醇的市场前景

麦角固醇在紫外线照射下可转化为维生素D2前体,加热异构失去两个氢原子得到VD2,是生产VD2、氢化可的松、黄体酮和芸苔素内酯的原料,市场需求呈上升趋势。麦角固醇的生产方法有发酵法和提取法两种,江西赣南制药厂、四川科德药业公司和四川汇鑫公司采用发酵法生产,总生产能力不足10t/a;山东东辰集团与北京化工大学合作开发了从青霉素发酵废菌丝体中提取麦角固醇的工艺技术,已建成生产能力为4t/a麦角固醇的工业性生产装置。     

S系列仪表分散型控制系统在工业中的应用

介绍Ｓ系列仪表分散型控制系统（ＦＹＺ－１００）在维生素Ｃ工程发酵工段中的应用     

Production of vitamins,coenzymes and related biochemicals by biotechnological processes

Vitamins and related biofactors belong to those few chemicals with a direct positive appeal to people. There is indeed a large need for extra vitamins, other than those derived from plant and animal food sources, due to unbalanced food habits or processing, food shortage or disease. Added vitamins are now either prepared chemically or biotechnologically via fermentation or bioconversion processes. Several vitamins and related biofactors are now only or mainly produced chemically (vitamin A, cholecalciferol (D₃), tocopherol (E), vitamin K₂, thiamine (B₁), niacin (PP or B₃), pantothenic acid (B₅), pyridoxine (B₆), biotin (H or B₈), folic acid (B₉) or via extraction processes (β-carotene or provitamin A, provitamin D₃, tocopherol, vitamin F-group). However, for several of these compounds microbiological or algal methods also exist or are rapidly emerging. Others are produced practically exclusively via fermentation (ergosterol or provitamin D₂, riboflavin (B₂), cyanocobalamin (B₁₂), orotic acid (B₁₃), vitamin F-group, ATP, nucleosides, coenzymes, etc. or via microalgal culture (β-carotene, E, F). Both chemical and microbial processes are run industrially for vitamin B₂ while vitamin C (ascorbic acid) is produced via a combination of chemical reactions and fermentation processes. A survey is given here of the current state of vitamin production, with emphasis on developments and strategies for improved biotechnological production and its significance, as compared to existing chemical processes. The screening or construction of vitamin hyperproducing microbial strains is a difficult task; pathway elucidation and metabolic (de)regulation need further study; r-DNA technology has only recently been introduced; improved fermentation processes and immobilised biocatalysts bioconversions for the synthesis of chiral vitamin compounds or intermediates or derivatives are gaining importance; the recovery and purification of these vitamin compounds from their fermentation broths remains equally complex.     

葡萄糖和木糖双底物生物合成2,3-丁二醇的条件优化

针对利用葡萄糖和木糖合成2,3-丁二醇的Klebsiella pneumoniae XJ-Li菌,优化培养基组成与发酵条件,围绕五、六碳糖共代谢的特点,探讨简单可行的代谢调控方法. 结果表明,60 g/L葡萄糖和40 g/L木糖为碳源,5.75 g/L NH4H2PO4为氮源,pH值维持在5.5,培养温度38℃, 2,3-丁二醇浓度可达19.24 g/L. 确定了pH值调控和外源添加维生素C的调控方式,通过调节发酵过程中pH值于5.5左右,使2,3-丁二醇的产量提高了16.4%;添加60 mg/L维生素C调节培养基的氧化还原状态,可使2,3-丁二醇的产量提高44.3%,批式发酵48 h, 2,3-丁二醇终浓度可达33.47 g/L.     

Study on the dissolved oxygen control strategy in large‐scale vitamin B12 fermentation by Pseudomonas denitrificans

BACKGROUND: There are two different routes for vitamin B₁₂ biosynthesis, which results in discrepancies and uncertainties of the dissolved oxygen (DO) concentration for vitamin B₁₂ fermentation. In this paper, the DO control strategy was explored for industrial vitamin B₁₂ fermentation by Pesudomonas denitrificans in 120000‐L fermenter. RESULTS: A DO‐stat strategy was first successfully scaled up from a 9000 L fermenter to a 120 000 L fermenter. Then a multi‐stage DO control strategy was further established in the 120 000 L fermenter, in which the DO level was shifted from 8–10% (20–48 h) to 2–5% (49–106 h) and below 2% (107–168 h) by gradually reducing the rate of aeration and agitation. As a result, 198.80 mg L^?1 of vitamin B₁₂ was obtained, which was significantly higher than those obtained under the fermentations with one‐stage DO control. CONCLUSIONS: The comparatively low DO level was favorable for vitamin B₁₂ biosynthesis, but it would have an extremely negative effect on cell growth. Compared with the low DO level maintained at all times of the fermentation process, a multi‐stage DO control strategy could not only increase the biomass but also improve vitamin B₁₂ biosynthesis. Copyright © 2012 Society of Chemical Industry     

H‐B‐E (hexanol‐butanol‐ethanol) fermentation for the production of higher alcohols from syngas/waste gas

CO, H₂, and CO₂ are major components of syngas and some industrial CO‐rich waste gases (e.g. waste gases from steel industries), besides some additional minor compounds. It was recently shown that those gases can be bioconverted, by acetogenic/solventogenic bacteria, into ethanol and higher alcohols such as butanol, but also hexanol, through the so‐called HBE fermentation. That process presents some advantages over existing chemical conversion processes. This paper reviews HBE fermentation from C1‐gases after briefly describing the more conventional ABE (acetone‐butanol‐ethanol) fermentation from carbohydrates by Clostridium acetobutylicum, in order to allow for comparison of both processes. Although acetone may appear in carbohydrate fermentation, alcohols are the only major end‐metabolites in the HBE process with Clostridium carboxidivorans. The few acetogenic bacteria known to metabolize C1‐gases and produce butanol or higher alcohols are described. Clostridium carboxidivorans has been used in most cases. Bioconversion of the gaseous substrates takes place in two stages, namely acidogenesis (production of acids) followed by solventogenesis (production of alcohols), characterized by different optimal fermentation conditions. Major parameters affecting each bioconversion stage as well as the overall fermentation process are analyzed. Although it has been claimed that acidification is required in ABE fermentation to initiate the solventogenic stage, strong acidification seems to some extent not to be a prerequisite for solventogenesis in the HBE process. Bioreactors potentially suitable for this type of bioconversion process are described as well. © 2017 Society of Chemical Industry     

Microbial and Genetic Resources for Cobalamin (Vitamin B12) Biosynthesis: From Ecosystems to Industrial Biotechnology

Many microbial producers of coenzyme B12 family cofactors together with their metabolically interdependent pathways are comprehensively studied and successfully used both in natural ecosystems dominated by auxotrophs, including bacteria and mammals, and in the safe industrial production of vitamin B12. Metabolic reconstruction for genomic and metagenomic data and functional genomics continue to mine the microbial and genetic resources for biosynthesis of the vital vitamin B12. Availability of metabolic engineering techniques and usage of affordable and renewable sources allowed improving bioprocess of vitamins, providing a positive impact on both economics and environment. The commercial production of vitamin B12 is mainly achieved through the use of the two major industrial strains, Propionobacterium shermanii and Pseudomonas denitrificans, that involves about 30 enzymatic steps in the biosynthesis of cobalamin and completely replaces chemical synthesis. However, there are still unresolved issues in cobalamin biosynthesis that need to be elucidated for future bioprocess improvements. In the present work, we review the current state of development and challenges for cobalamin (vitamin B12) biosynthesis, describing the major and novel prospective strains, and the studies of environmental factors and genetic tools effecting on the fermentation process are reported.     

中药材中维生素C含量测定方法的对比分析

通过对比分析的方法,确定在不同的中药材中维生素C含量的测定方法。将五味子、枸杞、山楂、大枣等药材进行研究,采用紫外分光光度法、二氯靛酚滴定法和高效液相色谱法3种方法进行维生素C的测定,对测定的过程和结果进行分析,选择最合适的维生素C测定的方法。结果表明,采用高效液相色谱法对维生素C进行测定的准确性最高,滴定法最简单,但是测试的结果不是特别准确,特别在测试颜色较深的样品中误差偏大。紫外分光光度法测定的结果与其他的两种方法比偏高,容易受到杂质的影响。高效液相色谱法在对中药中的维生素C测定中最合适,滴定法的局限性比较多,只能对颜色较浅的样品进行测定,紫外分光光度法在维生素C含量测定中不合适。