查询词典 acetoin

The a-ALDC can decarboxylate a-acetolactate directly to form acetoin without the formation of diacetyl.

ALDC可催化α-乙酰乳酸直接脱羧转化成乙偶姻，而不经过形成双乙酰的步骤。

It shown that PDC does not only catalyze the production of acetaldehyde (PDC's main activity), but also catalyzes an aldoltype condensation reaction in which the hydroxyethyl-ThDP intermediate of enzyme is condensed with a second acetaldehyde to form acetoin.

在研究中发现PDC不仅能催化产生乙醛，还具有醛连接酶的活性。即将二个乙醛分子缩合成3-羟基丁酮，尽管这个活性比产生乙醛的活性低得多。

The optimum HCI/ferrous chloride molar ratio was 1/3.3 when ironic chloride was generated by using hydrogen peroxide. The generated ironic chloride oxidized acetoin in good yield and could be recycled for many times.

用双氧水再生氯化铁时，加入浓盐酸最佳用量与氯化亚铁的摩尔比为1：3.3，再生后的氯化铁氧化效果良好，可多次循环使用。

Gas chromatography was employed to quantify the output of metabolization,and it was found that the yield of diacetyl for the mutant UV-3 was 18.7 fold to the wild-type 10293,up to 1.045g·L~(-1).Acetoin and ethanol yields were decreased by 48.4%and 71.4%,respectively.The yield of acetate was increased by 34.6%.

利用气相色谱测定代谢产物量，分析诱变前后菌株代谢途径中碳源的流向，结果表明突变株UV-3的丁二酮产量提高18.7倍，达到1.045g/L，乙偶姻产量降低48.4%，乙醇产量降低71.4%，乙酸产量提高34.6%，且遗传性质稳定。

The recoveries for 2,3-BD and acetoin were 91%and 92%,respectively.Aqueous two-phase extraction of 2,3-BD from real fermentation broth,the removal ratio of cells was above 99%,and the soluble proteins were about 85%in the top phase,which resulted in easy recovery of 2,3-BD from the top phase by vaporization because a viscous slurry was not formed by glucose,cells and soluble proteins at high temperature as in traditional separation methods.In addition,the cells recovered from the fermentation broth could be used as inoculum for further fermentation.

结果表明，目标产物2，3-丁二醇和乙偶姻主要富集在上相中，而葡萄糖主要富集在下相中；当异丙醇和硫酸铵的质量浓度分别是34%和20%时，2，3-丁二醇和乙偶姻的分配系数分别为8.29和8.98，回收率分别达到91%和92%；采用该条件对发酵液直接进行萃取，细胞的去除率在99%以上，可溶性蛋白去除率可达85%。

Therefore,K. pneumoniae CICC 10011 is a potential strain for 2,3-BD production.Thirdly,a novel aqueous two-phase system for the recovery of 2,3-BD from fermentation broth was developed employing isopropanol/(NH_4)_2SO_4 system.The results showed that most of target products(2,3-BD and acetoin) can be partitioned efficiently into the top phase,while most of glucose can be partitioned into the bottom phase.

通过对批式流加发酵过程中两株克雷伯氏菌代谢流量的分析表明，K.pneumoniaeCICC 10011代谢产生的各种有机酸和乙醇浓度均明显低于K.pneumoniae DSM 2026，而目标产物浓度以及产物转化率却相对较高，是发酵2，3-丁二醇的优良菌株。

The optimum initial substrate concentration for cultivation of inoculum was 8%.The optimum conditions for batch fermentation were 0.04vvm of air flow,5.8 of pH value.The fed-batch fermentation showed that the productivity of Klebsiella pneumoniae CICC 10011 was better than K.pneumoniae CGMCC 1206.The maximum concentration of 2,3-butanediol and acetoin was 103.38 g/L (90.98 g/L of 2,3-butanediol),and the yield reached 82.2%of its theoretical value.The fermentation conditions for K.pneumoniae.

确定种子培养的最适初始底物浓度为8%；间歇发酵的条件为：微氧发酵，通气量为0.04vvm，pH值为5.8；通过批式流加发酵实验表明：Klebsiella pneumoniae CICC 10011的代谢产2，3-丁二醇能力要远高于K.pneumoniaeCGMCC 1206，2，3-丁二醇最高浓度达90.98g/L，2，3-丁二醇与乙偶姻浓度之和最高达103.38g/L，转化率为理论最大值的82.2%，其发酵工艺还有待于进一步优化。

It manufactures heterocyclic, such as pyrazine, thiazole, furan, pyridine and sulf-compounds with their ramifications; and pharmaceutical intermediates such as veratraldehyde, isovanillin, sufurol, diacetyl, acetoin, and 2, 5-dimethyl pyrazine.

食用产品有吡嗪、噻唑、呋喃、吡啶等杂环系列及含硫系列的合成香料化合物。医药中间体产品有：藜芦醛、异香兰素、硫噻唑、丁二酮、乙偶姻、2，5-二甲基吡嗪等。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。