Authentication of Geographical Origin in Hainan Partridge Tea (Mallotus obongifolius) by Stable Isotope and Targeted Metabolomics Combined with Chemometrics

Abstract

Partridge tea (Mallotus oblongifolius (Miq.) Müll.Arg.) is a local characteristic tea in Hainan, the southernmost province of China, and the quality of partridge tea may be affected by the producing areas. In this study, stable isotope and targeted metabolomics combined chemometrics were used as potential tools for analyzing and identifying partridge tea from different origins. Elemental analysis—stable isotope ratio mass spectrometer and liquid chromatography-tandem mass spectrometrywas used to analyze the characteristics of C/N/O/H stable isotopes and 54 chemical components, including polyphenols and alkaloids in partridge tea samples from four regions in Hainan (Wanning, Wenchang, Sanya and Baoting). The results showed that there were significant differences in the stable isotope ratios and polyphenol and alkaloid contents of partridge tea from different origins, and both could accurately classify partridge tea from different origins. The correct separation and clustering of the samples were observed by principal component analysis and the cross-validated Q2 values by orthogonal partial least squares discriminant analysis (OPLS-DA) were 0.949 (based on stable isotope) and 0.974 (based on polyphenol and alkaloid), respectively. Potential significance indicators for origin identification were screened out by OPLS-DA and random forest algorithm, including three stable isotopes (δ13C, δ D, and δ18O) and four polyphenols (luteolin, protocatechuic acid, astragalin, and naringenin). This study can provide a preliminary guide for the origin identification of Hainan partridge tea.

Phytochemical composition of Lagenaria siceraria fruits from KwaZulu-Natal and Limpopo, South Africa

“…The intercepts of R 2 (0.0, 0.0003) and Q 2 (0.0, −0.006) with the vertical coordinates were less than one, the intercepts of Q 2 in vertical coordinates was less than zero indicating that the established OPLS-DA model had acceptable robustness ( Fig. 2 F) ( Fu et al, 2021 ). The projected variable importance plot (VIP) further identified phytochemicals with a VIP value >1 as significant contributors to the importance index ( Fu et al, 2021 ).…”

“…2 F) ( Fu et al, 2021 ). The projected variable importance plot (VIP) further identified phytochemicals with a VIP value >1 as significant contributors to the importance index ( Fu et al, 2021 ). This included the phytochemicals; E-15 Heptadecanal (Sesquiterpene), Hexadecen-1-ol, trans-9- (Fatty alcohol), E-14 Hexadecenal (Fatty alcohol), 1-Pentadecene (Sesquiterpene), Tridecane, 7-propyl- (Sesquiterpene), 2,3-Dimethyldodecane (Monoterpene), and Pentadecane, 3-methyl- (Sesquiterpene) ( Fig.…”

Metabolomics: A suitable foodomics approach to the geographical origin traceability of Ethiopian Arabica specialty coffees

“…Foodomics technology is an emerging area of science that is widely applicable in various research areas in different parts of the world for the traceability of regional foods via volatile aroma compound metabolomics fingerprinting, such as Philippine coffee (Ongo et al, 2020), Hainan Partridge tea (Fu et al, 2021), rice from China, Vietnam, and India (Ch et al, 2021), and many other products. However, in Ethiopia, the discipline is applied little in research and is in its infancy state.…”

The Cultivar Effect on the Taste and Aroma Substances of Hakka Stir-Fried Green Tea from Guangdong

“…Six of the measured compounds, ECG, EGC, EGCG, GC, GCG, and theanine, differed significantly in all teas (Figure 2A), which suggested that they may have been the main non-volatile components shaping the taste differences among the three HSGTs. A multivariate statistical analysis, OPLS-DA, which amplifies between-group differences and minimizes within-group differences, was used to visually simplify the HPLC results [35][36][37]. The score plot (Figure 2B) shows that the three HSGTs were clearly distinct in terms of their non-volatile profiles.…”