英语翻译MK-7isproducedby fermentationwithBacillus species.Becauseof the low concentration of MK-7 in fermentation processes,research has been focused on genetic mutation to improve theproductivity of bacteria [3,14,15] with limited attention paid

英语翻译MK-7isproducedby fermentationwithBacillus species.Becauseof the low concentration of MK-7 in fermentation processes,research has been focused on genetic mutation to improve theproductivity of bacteria [3,14,15] with limited attention paid
英语翻译
MK-7isproducedby fermentationwithBacillus species.Because
of the low concentration of MK-7 in fermentation processes,
research has been focused on genetic mutation to improve the
productivity of bacteria [3,14,15] with limited attention paid to
the effect of nutrients on improving the concentration [14].The
nutrients ina fermentationmedia (carbonandnitrogen) canhave
a significant impact on the concentration of MK-7.
Until recently the general practice was to determine the optimal conditions of media using one component at a time; however,this method does not describe the interactions among the
variables.Recently designof experiments (DOE)has beenused in
theoptimizationoffermentationmedia [16–18].Theobjectiveof
this studywas toinvestigatethe effectandoptimumcombination
of nutrients that can increase MK-7 production in batch fermentation.Factorial experimental design was used to screen and
determine the key nutrients that can have a significant impact
on MK-7 production.Central composite face design (CCF) was
then employed to achieve the optimum concentrations of significant variables selected through screening design on MK-7
production.Validation of fermentation was then conducted;
the substrate concentrations (i.e.amino acids and glycerol),pH
andbacterialgrowthwerealsomeasuredduringthe fermentation process.
mk-7是menaquinone-7

英语翻译MK-7isproducedby fermentationwithBacillus species.Becauseof the low concentration of MK-7 in fermentation processes,research has been focused on genetic mutation to improve theproductivity of bacteria [3,14,15] with limited attention paid
MK-7（甲基萘醌-7）是由发酵芽孢杆菌产生的.介于当前发酵过程中MK-7的浓度低,所以研究着重于寻找不需要在提升营养物浓度方面花费太多就能够提升细菌生产力的基因突变.发酵培养基中的营养物质（含碳,氮）对MK-7的浓度有显著影响.
到目前为止,一般的做法是一次改变一个条件,以确定培养基的最佳条件,但是这种方法无法描述变量之间的相互作用.最近的实验设计（DOE）主要是探究寻找最优状态的培养基.
本研究的目的是调查能够提升在批次发酵中甲基萘醌-7的产量的营养成分的效果和最佳配比.
因子实验设计被用来筛选和确定对MK- 7生产有显著影响的重要营养素.中心复合面设计（CCF）是用来筛选设计选定的显著变量的最佳浓度来生产MK-7的.然后发酵进行验证,同时在发酵过程中也测定了底物浓度（氨基酸和甘油）、pH值和细菌生长速度.