一种利用气相色谱快速检测瘤胃体外发酵液中三甲胺浓度的方法

本试验旨在建立一种利用气相色谱快速检测瘤胃体外发酵液中三甲胺浓度的方法。瘤胃体外发酵试验设置2个组,对照组(n=4)和试验组(n=4),试验组每个发酵瓶中添加0.0414 g三甲胺盐酸盐,发酵24 h。采用10 mol/L氢氧化钾溶液对发酵液样品进行预处理,使用WEL-PEG20M色谱柱和氢火焰离子检测器对三甲胺进行分离和检测。利用无三甲胺背景值的发酵培养基上清液配制不同浓度的三甲胺标准液,制备标准曲线。结果显示:三甲胺的标准曲线在0.1~1.0 mg/mL之间具有较好的线性关系(R 2≥0.993),平均回收率为98.44%~100.27%,三甲胺的最低检出限为0.01 mg/mL。对照组0和24 h发酵液均未检出三甲胺。试验组0 h发酵液三甲胺浓度为0.65 mg/mL,24 h发酵液三甲胺浓度为0.12 mg/mL,说明三甲胺被瘤胃微生物大量利用。综上所述,本试验建立的三甲胺检测方法操作步骤简单,准确度和灵敏度相对较高,能够快速准确监测发酵液中三甲胺浓度的变化,为瘤胃微生物三甲胺代谢研究提供了快捷高效的检测方法。

A Method for Rapid Detection of Concentration of Trimethylamine in Rumen in Vitro Fermentation Liquid by Gas Chromatography

This study aimed to establish a method for rapid determination of concentration of trimethylamine(TMA)in rumen in vitro fermentation liquid by gas chromatography.The rumen in vitro fermentation experiment was set two groups:control group(n=4)and experimental group(n=4).Each fermentation bottle in the experimental group was added with 0.0414 g trimethylamine hydrochloride,and all bottles were incubated 24 h.The fermentation liquid was pretreated with 10 mol/L potassium hydroxide(KOH).TMA was separated in WME-PEG20M column and detected by flame ionization detector.A series of TMA standard solution were prepared with the fermentation medium without background TMA to prepare standard curve.The results showed that the standard curve of TMA had a good linear relationship between 0.1 to 1.0 mg/mL(R 2≥0.993),the average recovery rates were 98.44%to 100.27%,and the detection limit of TMA was 0.01 mg/mL.TMA was not detectable in the fermentation liquid at 0 and 24 h in the control group.In the experimental group,the TMA concentrations were 0.65 mg/mL at 0 h and 0.12 mg/mL at 24 h,suggesting that TMA was greatly consumed by rumen microorganisms.In conclusion,the TMA detection method established in this study is simple procedure,relatively high accuracy and sensitivity,and can quickly,accurately monitor the changes of TMA concentration in the fermentation liquid.This method provides a fast and efficient detection method for the study of the TMA metabolism by rumen microorganisms.