Multielemental Analysis Associated with Chemometric Techniques for Geographical Origin Discrimination of Tea Leaves (Camelia sinensis) in Guizhou Province, SW China

Abstract

This study aimed to construct objective and accurate geographical discriminant models for tea leaves based on multielement concentrations in combination with chemometrics tools. Forty mineral elements in 87 tea samples from three growing regions in Guizhou Province (China), namely Meitan and Fenggang (MTFG), Anshun (AS) and Leishan (LS) were analyzed. Chemometrics evaluations were conducted using a one-way analysis of variance (ANOVA), principal component analysis (PCA), linear discriminant analysis (LDA), and orthogonal partial least squares discriminant analysis (OPLS-DA). The results showed that the concentrations of the 28 elements were significantly different among the three regions (p < 0.05). The correct classification rates for the 87 tea samples were 98.9% for LDA and 100% for OPLS-DA. The variable importance in the projection (VIP) values ranged between 1.01–1.73 for 11 elements (Sb, Pb, K, As, S, Bi, U, P, Ca, Na, and Cr), which can be used as important indicators for geographical origin identification of tea samples. In conclusion, multielement analysis coupled with chemometrics can be useful for geographical origin identification of tea leaves.

Comprehensive evaluation of the composition of Mingshan Laochuancha green tea and demonstration of hypolipidemic activity in a zebrafish obesity model

“…Mineral elements in teas have been reported in a number of papers, aiming to investigate the safety and distinction of different tea varieties and geographical origins. 2,[34][35][36][37] Individual and combined metal exposure can generate obvious harm to human health, such as cancers, mental retardation, behavioral abnormalities, low fertility and altered metabolism. Moreover, the ability to generate reactive oxygen species (ROS), depletion of glutathione and bonding to sulydryl groups of toxic metals are reported to be the main mechanisms underlying their toxicities to biological systems.…”

“…It is interesting to note that K was the richest element in previous reported teas. The specic incorporation within a binding ligand of tea leaves, 35 tea pruning and addition of K fertilizers to the soils, 1 might attribute to the high concentration of K. Additional, accumulating evidences have shown that green tea might be a rich source and accumulator of Mn, 2,34 and this might be a reason for high content of Mn in MLGT. Volatile compounds contribute signicantly to the tea aroma, which is one of the most important sensory properties, and has great inuence on the quality and consumer acceptance of tea.…”

“…1 According to historical records, tea plants are originated from southwest China, Sichuan, Yunnan, and Guizhou provinces. [2][3][4] Many ancient tea plants are distributed in these provenances of tea plants, and they are important genetic resources for breeding of new improved tea cultivars. Among them, Laochuancha (Camellia sinensis (L.) O. Kuntze.…”

Raman Spectroscopy Study of Phosphorites Combined with PCA-HCA and OPLS-DA Models

“…The OPLS-DA study was performed with SIMCA software v.14.1 (Umetrics, Umea, Sweden). The OPLS method is an extension of PLS and it is very helpful to find relevant information associated with particular samples and variables of a dataset [31][32][33][34][35]. R 2 X, R 2 Y, and Q 2 are the quality evaluation indexes of the models established in OPLS-DA analysis.…”

Use of mineral multi‐elemental analysis to authenticate geographical origin of different cultivars of tea in Guizhou, China

“…Mineral elements in tea leaves are relatively steady and are less affected by storage time and processing conditions. The mineral element composition of tea leaves has been increasingly measured to identify the leaves’ geographical origins . These studies proved the suitability of mineral elements as potential fingerprinting markers for the authentication of the geographical origin of tea.…”