Metabolomic data of phenolic compounds from Acer negundo extracts

Phytochemical and metabolomic data were obtained for the most important phenolic compounds in ethanolic extracts from the endangered Acer negundo tree in Morelia, Michoacan. Samples of leaves and stems were subjected to ethanolic extraction with electric rotavapor. We developed a metabolomic analysis that encompassed the correlation between the leaf and stem extracts through principal component analysis. The data were obtained with an infinity Agilent ultrahigh resolution liquid chromatograph coupled to a Agilent triple quadrupole mass spectrometer. The protocol used was a dynamic MRM (Multiple Reaction Monitoring). Clustering result shown as heatmap (distance measure using euclidean, and clustering algorithm using ward.D).


a b s t r a c t
Phytochemical and metabolomic data were obtained for the most important phenolic compounds in ethanolic extracts from the endangered Acer negundo tree in Morelia, Michoacan. Samples of leaves and stems were subjected to ethanolic extraction with electric rotavapor. We developed a metabolomic analysis that encompassed the correlation between the leaf and stem extracts through principal component analysis. The data were obtained with an infinity Agilent ultrahigh resolution liquid chromatograph coupled to a Agilent triple quadrupole mass spectrometer. The protocol used was a dynamic MRM (Multiple Reaction Monitoring).
Clustering result shown as heatmap (distance measure using euclidean, and clustering algorithm using ward.D).
© 2020 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license.

Specific subject area
Metabolomic analysis, liquid chromatography, mass spectrometry.

Type of data
Table, Figure, Image How data were acquired Leaf sample collection, stem sample collection, liquid chromatography, mass spectrometry.

Data format
Raw and Analysed Parameters for data collection Samples of leaves and stems of Acer negundo tree were collected and subjected to a dehydration process that required three days at a temperature of 50 °C in rotary evaporator.

Description of data collection
A botanical exploration of the samples was conducted to obtain the ethanolic extracts. The samples were filtered and then the solvent was evaporizated in an electric rotavapor to obtain the crude extracts. The samples were collected for metabolomic analysis by liquid chromatography and mass spectrometry. Identification and quantification of the analyzed phenolic compounds in leaf and stem extracts were obtained. A heat map was obtained. The equipment used was a UPLC coupled to a triple quadrupole mass spectrometer. The equipment was injected with 2 μL of ethanolic extract from leaves and 2 μL of ethanolic extract from stems.

Value of the data
• The data serve to identify and quantify the type and concentration of the metabolites present in the plant organs of Acer negundo. • The data collected could increase the knowledge about the level of phenolic compounds in endangered trees such as Acer negundo. • The distribution of the quantitative data could serve as a reference for metabolomic studies in other species of the genus Acer negundo. • The data of quantification of metabolites type phenolic compounds with antioxidant power in food chemistry allows the standardization of quality products from Acer negundo. • A correlation of metabolites and a database of metabolites of this species is obtained for metabolomics studies in trees of medical importance. • Currently, no metabolomic studies have been conducted on this species, and therefore it is important for studies in biochemistry, biosynthesis, plant physiology, plant biotechnology, phytochemistry and food chemistry.

Data Description
The data set in this article describes the metabolomics that includes all phenolic compounds synthesized in the leaves and stems of the Acer negundo tree. Fig. 1 describes the extraction process obtained from our protocol in which 80% ethanolic solution is used and the raw extract is obtained from a rotavaporizer. Currently, metabolomics allows the identification and quantification of total metabolites in a plant cell, or plant tissue [1,2] .
The protocol used was a dynamic MRM (Multiple Reaction Monitoring). The conditions for each compound are described in the Table 1 . The retention time variation allowed for the search of the compounds were 2 min in each case. The cell accelerator voltage was 7 V for each compound. Dilutions were made if the concentration of some compounds were higher than the linearity range.
Phenolic compounds are powerful antioxidants [1,2]. The 30 chemical structures of the analyzed phenolic compounds are presented in the extracts of leaves and stems of A. negundo ( Fig. 2 ).
Thirty phenolic compounds were quantified, in leaf extracts there were 30 compounds and in stem extracts there were 25 compounds ( Table 2 ). Fig. 3 shows a heat map of differential metabolites found by metabolomic analysis. The blue color represents the decreasing trend, the red represents an increasing trend. Fig. 4 shows the paired scorecards between the selected main components (PCs). The explained variance of each PC is shown in the corresponding diagonal cell. Fig. 5 shows a score chart between the selected main components (PCs). The variations explained are shown in brackets.
In Fig. 6 a 3D score plot is shown between the selected main components (PCs). The explained variations are shown in brackets. Fig. 7 shows a load plot for the selected main components (PCs). Fig. 8 shows a biplot of the main components among the selected PCs.

Extraction data acquisition
The samples come from an Acer negundo mother tree free of pests and diseases. Ten leaf and stem samples of A. negundo were collected and then subjected to a dehydration process that required three days (72 h) a temperature of 50 °C. Then 100 mg of dry matter was dissolved in 100 mL of 80% ethanol. The mixture was filtered using Whatman No. 1 filter paper. To obtain the raw extracts, a rotary evaporator was used.

Identification and quantification of phenolic compounds
The identification and quantification of phenolic compounds was performed basically as it was previously reported in Juárez-Trujillo et al ., 2018 [3] and Monribot et al ., 2019 [4] . The equipment used was a UPLC coupled to a triple quadrupole mass spectrometer. The equipment was injected with 2 μL of ethanolic extract from leaves and 2 μL of ethanolic extract from stems.

Sample preparation
Samples were filtered with 0.5 μm PTFE membranes and placed in 2 mL UPLC vials.

Chromatographic conditions
The data were obtained with a 1290 infinity Agilent ultrahigh resolution liquid chromatograph coupled to a 6460 Agilent triple quadrupole mass spectrometer. The mobile phases were  water with 0.1% of formic acid (A) and acetonitrile with 0.1% formic acid (B), both in MS grade. The gradient elution profile is presented in the Table 3 .
The flow was 0.3 mL/min. The injection volume was 2 μL. The column was a Waters, BEH, 2.1 × 50 mm, 1.7 Microns. The column temperature was 40 °C.

Mass spectrometry conditions
The conditions of mass spectrometry is presented in the Table 4 .