生物传感仪-除NH4^(+)法测定发酵液中L-谷氨酸含量的研究  

Study on determination of L-glutamic acid by biosensor removing NH4^(+)method

作　　者：张金露 吴涛 唐艳 ZHANG Jin-lu;WU Tao;TANG Yan(Tongliao Meihua Bio-tech Co.,Ltd.,Tongliao 028024)

机构地区：[1]通辽梅花生物科技有限公司,通辽028024

出　　处：《中国食品添加剂》2021年第1期86-91,共6页China Food Additives

摘　　要：采用生物传感仪法测定谷氨酸发酵液含量,由于此法反应产物有铵根离子(NH4^(+)),而发酵后期样品中NH4+浓度高达20g/L,产生逆反应,使发酵液检测结果偏低,导致提取出现收率超百现象。为解决此问题,本文建立一种除NH4+法检测谷氨酸发酵液中谷氨酸含量的新方法,并对仪器进行线性校正,将发酵液在碱性加热条件下,使NH4+祛除,再调样液pH至中性,使用生物传感仪测定含量。结果表明:RSD<2%,回收率在95%~110%之间,以HPLC衍生法测定的结果作为参考,此法准确性很高(平均误差为0.12%)。且新方法保留原生物传感仪法优点的同时,更适合发酵后期样品检测,满足味精发酵行业对谷氨酸发酵终点样品准确测定的要求。The content of glutamic acid in fermentation broth was determined by biosensor.Because of NH4^(+)produced in the reaction and its high concentration of 20g/L at later stage of fermentation,the reverse reaction occurs.This not only causes glutamic acid testing result lower in later stage of fermentation,but also leads to extraction yield over 100%.To solve this problem,a new method which remove NH4+from the fermentation broth was established.Before detected by biosensor,the instrument was re-calibrated,heating with alkaline was used to removing of NH4^(+),and pH was adjusted to neutral.The results showed that RSD was less than 2%,and the recovery rate was between 95%and 110%.The accuracy of this method is very high with the average error of 0.12%.The new method is more suitable for detecting samples at the later stage of fermentation,and meets the requirements of MSG fermentation industry in determination of glutamic acid endpoint products.

关 键 词：L-谷氨酸 发酵液 生物传感仪 铵根离子 

分 类 号：TQ922.1[轻工技术与工程—发酵工程] TQ92