Rapid discrimination of raw and sulfur-fumigated Smilax glabra based on chemical profiles by UHPLC-QTOF-MS/MS coupled with multivariate statistical analysis

• Published in: Food research international Vol. 108; pp. 226 - 236
• Main Authors: He, Lili, Zhang, Zhifeng, Liu, Yuan, Chen, Dingqiao, Yuan, Muhua, Dong, Gengting, Luo, Pei, Yan, Zhigang
• Format: Journal Article
• Language: English
• Published: Canada Elsevier Ltd 01.06.2018
• Subjects: Chemical transformation; Smilax glabra; Sulfur-fumigation; UHPLC-QTOF-MS/MS; Smilaside C (PubChem CID: 10919948); Chemical transformation; 5-O-Caffeoylshikimic acid (PubChem CID: 5281762); Neoastilbin (PubChem CID: 442437); Sulfur-fumigation; Neoisoastilbin (PubChem CID: 10114809); Smilax glabra; UHPLC-QTOF-MS/MS; Astilbin (PubChem CID: 119258); Smilaside A (PubChem CID: 11614748); Glucosyringic acid (PubChem CID: 10383888); Smilaside B (PubChem CID: 11629132); kaempferol-7-O-β-d-glucoside (PubChem CID: 10095180); Epicatechin (PubChem CID: 72276)
• DOI: 10.1016/j.foodres.2018.03.047
• ISSN: 0963-9969

Smilax glabra (SG) is commonly used as a traditional edible herb in eastern Asia. Recently, sulfur-fumigation has been frequently used in order to obtain better color and a longer storage lifetime. However, the chemical alterations caused by this process remain unknown. The aim of this research was to explore potential chemical differences between non-fumigated and sulfur-fumigated SG samples. A novel approach was developed by using ultra-high-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry (UHPLC-QTOF-MS/MS) with principal component analysis (PCA) and orthogonal partial squared discriminant analysis (OPLS-DA). Fifty-eight compounds were unambiguously characterized or tentatively identified in the chemical profiles for the first time. Six newly generated sulfur-containing compounds, namely glucosyringic acid sulfate, 5-O-caffeoylshikimic acid sulfite, 3-O-caffeoylshikimic acid sulfite, 5-O-caffeoylshikimic acid sulfate, 3-O-caffeoylshikimic acid sulfate and astilbin sulfate, were screened out to be the most characteristic markers for distinguishing non-fumigated and sulfur-fumigated SG. This newly proposed approach can not only be applied for exploring chemical markers but can also be used to investigate the chemical transformation mechanism associated with sulfur for other edible herbs. [Display omitted] •The chemical compositions of Smilax glabra were analyzed systematically.•The influence of sulfur fumigation on chemical profiles of SG was evaluated.•The difference between raw and fumigated SG was investigated by PCA and OPLS-DA.•58 compounds were identified and 6 compounds were newly produced.•Six sulfur-containing compounds were screened out as potential chemical markers.