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本文叙述了以L—谷氨酸为原料,经过酯化、氨解、酸解等工艺路线制备L—谷氨酰胺的方法。本工艺综合了德国和日本专利所报导的合成方法,结合我们的工作实践,在酰化反应后不将所生成的L—谷氨酸—r—甲酯分离出来,而采用低溫酯化以控制L—谷氨酸二甲酯的生成,并在产品精制过程中采用树脂方法,分离少量未反应完全而混入产品中的L—谷氨酸。此法优点是:中间产物不用分离,减少了工艺步骤;操作简便,易实施工业大生产;减少了设备投资。采用本法生产的L—谷氨酰胺质量符合日本味之素公司的质量标准,收率达到理论值的52.8%。本工艺于一九八三年十二月在武汉通过技术鉴定。 相似文献
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本文叙述了以L—谷氨酸为原料,经过酯化、氨解、酸解等工艺路线制备L—谷氨酰胺的方法。本工艺综合了德国和日本专利所报导的合成方法,结合我们的工作实践,在酰化反应后不将所生成的L—谷氨酸—r—甲酯分离出来,而采用低溫酯化以控制L—谷氨酸二甲酯的生成,并在产品精制过程中采用树脂方法,分离少量未反应完全而混入产品中的L—谷氨酸。此法优点是:中间产物不用分离,减少了工艺步骤;操作简便,易实施工业大生产;减少了设备投资。采用本法生产的L—谷氨酰胺质量符合日本味之素公司的质量标准,收率达到理论值的52.8%。本工艺于一九八三年十二月在武汉通过技术鉴定。 相似文献
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<正> 1877年Schulze,Barbieri推定在南瓜的发芽植物中,存在着加热后产生氨变成谷氨酸的一种物质,而这种物质就是谷氨酰胺。但是,当时还不能够分离出谷氨酰胺。1883年,Schulze和B(?)sshard协作,将分离游离的天门冬氨酸使用的硝酸汞沉淀法用在甜菜上,成功地抽提出谷氨酰胺。在甜菜根的水抽提物中,加入碱式醋酸铅,然后滤去沉淀物。接着,在滤液中加入硝酸汞,就得到谷氨酰胺的汞盐。用硫化氢除汞,滤液用氨中和。经浓缩析出谷氨酰胺结晶。此结晶物不含结晶水,元素分析结果跟C_6H_(10)N_2O_3一致。 相似文献
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<正> 一、前言 1957年木下等发表谷氨酸棒杆菌(Corynebacterium glutamicum)进行谷氨酸的工业生产以来,日本的氨基酸发酵生产的研究有很大的进展。很多氨基酸已能用发酵法生产。谷氨酰胺和N-乙酰-I-谷氨酰胺(N-AGM)作为胃溃疡、十二指肠溃疡病等的抗溃疡病药物正在大量应用。作者等应用谷氨酸产生菌谷氨酸棒杆菌的野生株,通过控制环境因素使谷氨酸发酵转换成谷氨酰胺和N-AGM发酵,建立了这些氨基酸的工业生产方法。同时也研究了从谷氨酸发酵转换生产脯氨酸的方法。通过改变培养条件,用谷氨酸棒杆菌使发 相似文献
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<正> 1877年Schulze,Barbieri推定在南瓜的发芽植物中,存在着加热后产生氨变成谷氨酸的一种物质,而这种物质就是谷氨酰胺。但是,当时还不能够分离出谷氨酰胺。1883年,Schulze和B(?)sshard协作,将分离游离的天门冬氨酸使用的硝酸汞沉淀法用在甜菜上,成功地抽提出谷氨酰胺。在甜菜根的水抽提物中,加入碱式醋酸铅,然后滤去沉淀物。接着,在滤液中加入硝酸汞,就得到谷氨酰胺的汞盐。用硫化氢除汞,滤液用氨中和。经浓缩析出谷氨酰胺结晶。此结晶物不含结晶水,元素分析结果跟C_6H_(10)N_2O_3一致。 相似文献
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本文着重介绍了以野生型谷氨酸产生菌ATCC14067为亲株,经过亚硝基胍处理,筛选对磺胺胍具有抗性的突变株,再经过生长试验及稳定性试验,最后选育出两株稳定性好、付产物谷氨酸少的L—谷氨酰胺高产菌株。 L—谷氨酰胺(L—2—氨基戊二酸—酰胺)是L-谷氨酸的r-羧基酰胺化,在医药上是一种极有价值的氨基酸。自1952年用X光衍射确定了其分子结构后,对它的应用日益引起人们的关注。目前国外临床上主要用于治疗精神萎靡、酒精中毒及胃和十二指肠溃疡等疾病;它又是合成脑功能改善药N—乙酰谷酰胺的重要中间物。从谷氨酸产生菌的野生型菌株ATCC14067通过改变发酵条件直接发酵生产L-谷氨酰胺,我们以前曾有过报导。我们通过诱变选育到两株对磺胺胍具有抗性的变异株。变异株的谷氨酰胺产量提高,发酵付产品谷氨酸的量也有减少,为以后提取分离提供了方便。 相似文献
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Yong Tang Liwei Zhu Weiming Zhang Xinhui Shang Jianxin Jiang 《Applied microbiology and biotechnology》2013,97(5):1923-1932
The sequential production of bioethanol and lactic acid from starch materials and lignocellulosic materials was investigated as ethanol fermentation broth (EFB) can provide nutrients for lactic acid bacteria. A complete process was developed, and all major operations are discussed, including ethanol fermentation, broth treatment, lactic acid fermentation, and product separation. The effect of process parameters, including ethanol fermentation conditions, treatment methods, and the amount of EFB used in simultaneous saccharification and fermentation (SSF), is investigated. Under the selected process conditions, the integrated process without additional chemical consumption provides a 1.08 acid/alcohol ratio (the broth containing 22.4 g/L ethanol and 47.6 g/L lactic acid), which corresponds to a polysaccharide utilization ratio of 86.9 %. Starch ethanol can thus promote cellulosic lactic acid by providing important nutrients for lactic acid bacteria, and in turn, cellulosic lactic acid could promote starch ethanol by improving the profit of the ethanol production process. Two process alternatives for the integration of starch ethanol and cellulosic lactic acid are compared, and some suggestions are given regarding the reuse of yeast following the cellulosic SSF step for lactic acid production. 相似文献
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XuDong Wang ChunYan Hu Chao Qin YueSheng Dong GuoQing Ying ZhiLong Xiu ZhiGuo Su 《Engineering in Life Science》2021,21(10):643
Clavulanic acid (CA) is usually used together with other β‐lactam antibiotics as combination drugs to inhibit bacterial β‐lactamases, which is mainly produced from the fermentation of microorganism such as Streptomyces clavuligerus. Recently, it is still a challenge for downstream processing of low concentration and unstable CA from fermentation broth with high solid content, high viscosity, and small cell size. In this study, an integrated process was developed for simultaneous solid–liquid separation and primary purification of CA from real fermentation broth of S. clavuligerus using salting‐out extraction system (SOES). First, different SOESs were investigated, and a suitable SOES composed of ethanol/phosphate was chosen and further optimized using the pretreated fermentation broth. Then, the optimal system composed of 20% ethanol/15% K2HPO4 and 10% KH2PO4 w/w was used to direct separation of CA from untreated fermentation broth. The result showed that the partition coefficient (K) and recovery yield (Y) of CA from untreated fermentation broth were 29.13 and 96.8%, respectively. Simultaneously, the removal rates of the cells and proteins were 99.8% and 63.3%, respectively. Compared with the traditional method of membrane filtration or liquid–liquid extraction system, this developed SOES showed the advantages of simple operation, shorter operation time, lower process cost and higher recovery yield of CA. These results demonstrated that the developed SOES could be used as an attractive alternative for the downstream processing of CA from real fermentation broth. 相似文献
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In this study, a multi-stage membrane process, assisted by vacuum evaporation and crystallization, for recovery of bio-based alpha-ketoglutaric acid from the actual post-fermentation broth was designed and investigated. In the first part of this study, pre-treatment of crude fermentation broth (centrifugation-ultrafiltration-nanofiltration) was carried out to remove biomass, proteins, sugars, part of inorganic ions and color compounds. The commercial ceramic UF membrane (15 kDa) and nanofiltration ceramic membrane (200 Da or 450 Da) were applied. Electrodialysis with a bipolar membrane was proposed for separation of ionic compounds and simultaneous electro-acidification to the acid form. During bipolar membrane electrodialysis carried out under acidic conditions, it was possible to remove close to 90 % of alpha-ketoglutaric acid. Moreover, the migration of other acids present in the fermentation broth (lactic and acetic) was significantly limited. The calculated specific energy consumption was low and equal to 0.6 kW h/kg. The final purification using crystallization assisted vacuum evaporation allowed obtaining alpha-ketoglutaric acid in solid form. Analysis of the final product showed that the proposed method of alpha-ketoglutaric acid recovery gives the acid of high purity equal to 94.8 %. Furthermore, the presented results have practical relevance and may in future be the basis for the development of separation technologies of alpha-ketoglutaric acid from the fermentation broth on industrial scale. 相似文献
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Cheng KK Zhao XB Zeng J Wu RC Xu YZ Liu DH Zhang JA 《Applied microbiology and biotechnology》2012,95(4):841-850
Succinic acid is a promising chemical which has a wide range of applications and can be biologically produced. The separation of succinic acid from fermentation broth makes more than 50?% of the total costs in their microbial production. This review summarizes the present state of methods studied for the recovery and purification of biologically produced succinate. Previous studies on the separation of succinic acid primarily include direct crystallization, precipitation, membrane separation, extraction, chromatography, and in situ separation. No single method has proved to be simple and efficient, and improvements are especially needed with regard to yield, purity, and energy consumption. It is argued that separation technologies coupled with upstream technology, in situ product removal, and biorefining strategy deserve more attentions in the future. 相似文献
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The separation of lactic acid from complex fermentation broth was examined. Liquid–liquid extraction using reversible chemical complexation for reactive extraction was chosen to be the separation method. Over 50% yield of lactic acid was obtained from fermented broth in a single extraction step, when using the tertiary amine as the extractant, 1-dekanol as the diluent and trimethylamine (TMA) as the stripping solution. The effect of complex media on the extraction behaviour has hardly been examined previously. 相似文献
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双极膜电渗析分离发酵液中L-乳酸 总被引:1,自引:0,他引:1
采用三室型双极膜电渗析装置将发酵液中的L-乳酸钠转化为L-乳酸。探讨操作电压、流速、进料L-乳酸钠质量浓度等工艺参数对转化过程的影响,考察电渗析过程参数对转化率、物料损失率、电流效率和能耗等技术指标的影响。在最优操作条件下(流速40L/h,电压15V)对2L的100.25g/L乳酸钠发酵液进行分批重复电渗析处理。结果表明:整个过程的转化率为81.22%,损失率为1.5%,能耗为0.81kW·h/kg,电流效率为91.8%,得到的L-乳酸质量浓度可达144.31g/L.电渗析残液补糖后可回到发酵罐中用于发酵生产L-乳酸. 相似文献
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比较褐藻胶裂解酶产生菌Alteromonassp .在摇瓶和发酵罐培养过程中生物量、褐藻胶寡糖含量以及褐藻胶裂解酶活性的变化 ,根据其变化确立了通过微生物发酵 膜分离技术结合制备褐藻胶寡糖的条件 ,并对寡糖进行凝胶过滤色谱和薄层色谱分析。用组成为每升含酵母粉 5g、蛋白胨 10g、FeSO4 0 1g、褐藻酸钠 12g、NaCl 1 5g ,pH为7 5的培养基 ,在 2 8℃培养褐藻胶裂解酶产生菌 ,结果表明 ,发酵罐培养 30h ,发酵液寡糖含量达到最大。发酵液通过超滤 纳滤两级膜分离 ,得到褐藻胶寡糖 ,寡糖的回收率和脱盐率分别为 94 0 %和 93 3%。通过凝胶柱分离和TLC分析 ,得到 5个褐藻胶寡糖组分。 相似文献
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Ataei SA Vasheghani-Farahani E 《Journal of industrial microbiology & biotechnology》2008,35(11):1229-1233
Lactic acid fermentation is an end product inhibited reaction. In situ separation of lactic acid from fermentation broth using
ion exchange resins was investigated and compared with conventional fermentation system. Amberlite resin (IRA-400, Cl−) was used to separate lactic acid from fermentation broth and pH was controlled online with an automatic pH controller. The
effect of process variables on lactic acid production by Lactobacillus casei in whey permeate was studied. The maximum productivity was obtained at pH = 6.1, T = 37 °C and impeller speed = 200 rpm. The maximum concentration of lactic acid at optimum condition was found to be 37.4 g/L
after 38 h of fermentation using in situ separation system. The productivity of in situ separation system was five times increased
in comparison with conventional system. 相似文献