一种低场核磁共振技术快速定量检测发酵液油浓度方法

摘要

The purpose of this paper is to develop a more convenient,rapid and unpretreated method to measure the oil content in the culture medium.A quantitative method for determining the oil content in the fermentation medium using low field NMR(LF-NMR) instruments has been developed.All components of the medium were detected using the LF-NMR technology and the relaxation time of oil is about 100ms using LF-NMR.Except for soybean flour and wheat germ flour,no ingredients had significant effects on the oil peak area in the single-factor experiments.The oil content determined by LF-NMR tests showed that it had a good stability (CV=4.4％) and accuracy of about 1.0％.In addition,the oil contents determined by the method of N-hexane extraction and LF-NMR technology presented a linear relationship with a correlation R2 of 0.9581.The LF-NMR method is more convenient and accurate than the traditional methods of oil detections such as n-hexane extraction,indicating that LF-NMR method could be applied in the industrial process to monitor the oil content in the broth.%建立了一种方便、快捷和无损的低场核磁共振(LF-NMR)技术检测发酵液中油的方法.通过对培养基中各成分的检测,确定了油脂的弛豫时间约100ms;单因素实验表明除了黄豆粉和胚芽粉造成取样不均对油峰面积有一定的影响,其他成分对油峰面积无明显影响;含油量不同的梯度实验结果表明了LF-NMR检测油时有良好的稳定性(相对偏差约为4.4％)和精确性(约1.0％);正己烷萃取法测定油浓度与LF-NMR法测定的油浓度进行线性相关分析,相关性良好(R2=0.9581).因此,应用LF-NMR检测发酵液中油浓度比传统的检测方法(如正己烷萃取法等)更方便和准确,可应用于工业发酵监控.