ABSTRACT
Due to the extensive use of xylooligosaccharides (XOS) as functional food ingredients,many inferior goods and even adulterants are generally found in the market,which may pose a health hazard to certain populations.Chromatography method such as high-performance liquid chromatography (HPLC) and high-performance thin-layer chromatography (HPTLC) is traditionally applied for the quality analysis of XOS.However,it is time consuming due to the prolonged separation and pre-or post-derivatization procedure.In this study,a fast saccharide mapping method based on matrix-assisted laser desorption/time-of-flight mass spectrometry (MALDI-TOF-MS) was developed for the quality consistency analysis of 22 batches of XOS collected from different manufacturers in China.The time needed for saccharides analysis using MALDI-MS was less than 30 min for one plate,at least 6 times faster than that by the traditional HPTLC chromatography method.In addition,MALDI-MS possessed higher resolution for XOS with DP4-DP7 based on the difference of m/z,which is hardly separated using HPTLC.The results showed that XOS were present only in samples XY01-XY11,samples XY12-XY14 only consisted of hex oligo-saccharides,and samples XY15-XY22 were free of oligosaccharides.These indicate that the quality consistency of XOS products in the China market was poor,which should be carefully investigated.