Analysis of Chemical Constituents in Paullinia cupana Dried Seeds by UPLC-Q-TOF-MS / 中国实验方剂学杂志

ABSTRACT

Objective:The chemical constituents in guarana （<italic>Paullinia cupana</italic> dried seeds） were systematically analyzed to provide a basis for further research， development and utilization of this plant. Method:The contents of crude protein， crude fat， crude polysaccharide and crude fiber in guarana were determined according to national standards and related documents， and the chemical constituents of guarana was qualitatively analyzed by ultra performance liquid chromatography-quadrupole-time-of-flight mass spectrometry （UPLC-Q-TOF-MS）， ACQUITY UPLC-HSS-T3 column （2.1 mm×100 mm， 1.8 μm） was used with 0.1% formic acid aqueous solution （A）-0.1% formic acid acetonitrile solution （B） as mobile phase for gradient elution （0-5 min， 2%-10%B； 5-6 min， 10%-20%B； 6-9 min， 20%-30%B； 9-9.5 min， 30%-35%B； 9.5-10.5 min， 35%-45%B； 10.5~13 min， 45%-55%B； 13-15 min， 55%-80%B； 15-19 min， 80%-98%B； 19-20 min， 98%B； 20-20.3 min， 98%-2%B； 20.3-23 min， 2%B）， the electrospray ionization （ESI） was used for detection in positive and negative ion modes， the scanning range was <italic>m</italic>/<italic>z</italic> 50-1 500， and the structure was identified according to the relative molecular weight and fragment information combined with database matching and comparison of reference substances. Result:The contents crude protein， crude fat， crude polysaccharide and crude fiber in guarana were （0.63±0.03）%， （2.73±0.09）%， （3.23±0.12）% and （8.89±0.59）%， respectively. A total of 42 chemical constituents in guarana were identified by UPLC-Q-TOF-MS， including 3 methylxanthines， 2 nucleosides， 1 amino acid， 3 organic acids， 33 flavonoids， 3 （<italic>L</italic>-tryptophan， epigallocatechin gallate， daidzein） of which were first discovered in guarana. Conclusion:Guarana is rich in nutrients and has good potential to be developed as a functional food. UPLC-Q-TOF-MS technique provides a simple， rapid and accurate method for the identification of chemical constituents in guarana. Methylxanthines and proanthocyanidins are the main chemical constituents of guarana， which is meaningful for quality evaluation and material basis of guarana.