Enzymatic-fingerprinting workflow of polysaccharides in Hericium erinaceus fruiting bodies: From HILIC-ESI--MS screening to targeted MIM profiling.

In this study, an uncommon enzymatic-fingerprinting workflow, was proposed for characterization and discrimination of mushroom polysaccharides (MPs) by hydrophilic interaction liquid chromatography-negative electrospray mass spectrometry (HILIC-ESI--MS). Firstly, the HILIC-ESI--MS was used to screen and identify the enzymatic digestion products of MPs using HILIC-Orbitrap based on full scan and MS/MS modes. Secondly, a targeted structural-fingerprinting of polysaccharides (SFP) was built in a multiple-ion monitoring (MIM) mode using the same HILIC separation with a triple quadrupole MS. Thirdly, a case study of polysaccharides in Hericium erinaceus fruiting bodies (HEP) was performed to obtain the expected SFP based on dextranase digestion that allows for visual discrimination of polysaccharides from other five edible mushrooms attributed to Agrocybe cylindracea, Arimillaria mellea, Flammulina velutipes, Pleurotus eryngii, and Lentinula edodes. Furthermore, a major structural backbone of HEP was unveiled by occurrence of → 6(Hex)1 → along with multiple possible substitutions including of terminal GalA, Fuc, acetyl, → 4Hex1 →, and → 3Hex1 →. Finally, the similarity analysis, hierarchical cluster analysis (HCA), and partial least squares discriminant analysis (PLS-DA) were performed to visualize various MPs. As a result, the enzymatic-fingerprinting workflow presents an effective example for quality evaluation of fungi polysaccharides using a SFP strategy.