Gutzeit Derek, Klaubert Bernd, Rychlik Michael, Winterhalter Peter, Jerz Gerold
Central Institute of the Bundeswehr Medical Service Munich, Ingolstädter Landstrasse 102, 85748 Garching, Hochbrück, Germany.
J Agric Food Chem. 2007 May 16;55(10):3978-84. doi: 10.1021/jf070223+. Epub 2007 Apr 21.
A stable isotope dilution assay for quantification of pantothenic acid in sea buckthorn berries, juice, and concentrate using a four-fold labeled isotopologue of vitamin B5 as the internal standard was adopted using reversed phase liquid chromatography-mass spectrometry with electrospray ionization. Because of a rapid sample clean up procedure without the necessity of external calibration, this methodology permits the accurate analysis of a high number of samples within a short time. Sea buckthorn juice was stored at 25 and 40 degrees C for up to 7 days to determine the effects of storage temperature on the stability of pantothenic acid. Analysis of kinetic data suggested that the degradation follows a first-order model. The results of the experiments showed that storage of sea buckthorn juice for 7 days at ambient temperature (25 degrees C) already resulted in a significant degradation of pantothenic acid of about 18%. The processing effects of juice production and subsequent concentration revealed a decrease of about 6-7% in the juice and of 23% in the juice concentrate.
采用反相液相色谱-电喷雾电离质谱联用技术，以维生素B5的四重标记同位素类似物作为内标，建立了一种稳定同位素稀释分析法，用于定量测定沙棘浆果、果汁和浓缩汁中的泛酸。由于样品快速净化程序无需外部校准，该方法能够在短时间内对大量样品进行准确分析。将沙棘汁分别储存在25℃和40℃下长达7天，以确定储存温度对泛酸稳定性的影响。动力学数据分析表明，降解过程符合一级模型。实验结果表明，沙棘汁在环境温度（25℃）下储存7天，泛酸已出现约18%的显著降解。果汁生产及后续浓缩过程中的加工影响显示，果汁中泛酸含量降低约6-7%，浓缩汁中降低23%。
