Data on polyphenols and biological activity analyses of an Andean tomato collection and their relationships with tomato traits and geographical origin

Data provide information about a tomato collection composed of accessions from the Andean Valley, commercial accessions and wild species. Antioxidant metabolites were measured in mature fruits of this collection, and their biological activities were assessed by both in vitro and in vivo methods. In this work, the parameters used to identify and quantify polyphenols compounds in tomato fruit by liquid chromatography coupled to diode array detector and quadrupole time of flight mass spectrometer are described. Moreover, data supporting a procedure to characterize the properties of tomato fruits to revert death by thermal stress in Caenorhabditis elegans are explained in detail. Lastly, principal component analysis and hierarchical cluster analysis of metabolites composition, antioxidant activities (in vivo and in vitro), tomato traits and geographical origin of the tomatoes collection are shown. The data presented here are related to the research article entitled “Hydrophilic antioxidants from Andean Tomato Landraces assessed by their bioactivities in vitro and in vivo” [1].

shown. The data presented here are related to the research article entitled "Hydrophilic antioxidants from Andean Tomato Landraces assessed by their bioactivities in vitro and in vivo" [1]. &

Data
Tomato accessions collected from Andean valleys, commercial varieties and wild species were characterized according to their fruit traits and geographical origin (Table 1). Fruit polyphenols levels were measured by LC-DAD-MS (Table 2, Figs. 1 and 2). Relationships between polyphenols composition, fruit traits and geographical origin were analyzed (Figs. 3 and 4). The capacity of fruit extract to confer tolerance to thermal stress in a Caenorhabditis elegans model was evaluated (Fig. 5). Relationships between in vitro and in vivo antioxidant activities and fruit traits and geographical origin were analyzed (Figs. 6 and 7).

Experimental design, materials and methods
Sixteen tomato accessions composed of tomatoes collected from Andean valleys, commercial tomatoes and wild species (Table 1)    geographical origin were analyzed (Figs. 3 and 4). The capacity of fruit extract to confer tolerance to thermal stress in a C. elegans model was evaluated (Fig. 5). Relationships between in vitro and in vivo antioxidant activities and fruit traits and geographical origin were analyzed (Figs. 6 and 7). Table 1 compiles the tomato species, accessions numbers, geographical origin, fruit traits, and uses of 16 tomato accessions. At ripening stage defined by color and firmness, three fruits per plant were harvested from three individual plants, around 60 and 65 days after anthesis, and were immediately frozen with liquid nitrogen and kept in polyethylene tubes at À 80°C until use.

Polyphenols extraction
The obtention of tomato hydrophylics extracts is explained in detail in Di Paola et al. [1].

LC-DAD-MS analysis
The phenolic compounds from tomato samples were analyzed by HPLC-DAD-ESI-MS/MS method. The equipment and procedure are described in Di Paola et al. [1]. Tentative identification of phenolic compounds was based on their retention times, elution order, UV-vis spectra and MS fragmentation spectra as compared with phenolic standards ( Table 2). For polyphenols quantification, the mass peak areas were obtained from the extracted ion chromatograms (Figs. 2 and 3).

Relationship between antioxidant composition and fruits traits
Principal component analysis (PCA) of antioxidant composition and fruit traits of tomato collection was performed using Infostat Software [2]. Fig. 3 shows the biplot graphic of two main principal components: (a) shows the score plot displaying fruit traits and (b) shows the loading plot displaying the antioxidant metabolites.

Relationship between antioxidant composition and geographical origin
PCA was also performed to access the correlations between antioxidant composition and geographical origin (and altitude). Biplot graphics of the two main components are shown in Fig. 4: (a) shows the score plot of geographical origin and altitude, and (b) shows the loading plot of antioxidant metabolites.

C. elegans assay
For in vivo assays, 1 mL of hydroalcoholic extract from each of the three biological replicates was pooled and dried. Afterwards, the dry residue was dissolved in 200 ml dimethyl sulfoxide (DMSO) and kept at À 80°C until use.
Worms were reproduced and maintained at 20°C on nematode growth medium (NGM) plates using Escherichia coli OP50 as food source. When worms reached the young adult stage (three days after synchronization of the worms [3]), at least 30 young adults were transferred to plates containing fresh medium supplemented with serial dilutions of the tomato fruit extracts. Each experiment was carried out in triplicate using the hydroalcoholic extracts and 1% (v/v) DMSO as a vehicle control. After incubation at 20°C for 18 h, worms were subjected to heat stress by treatment at 37°C for 5 h 40 min causing the death of more than 50% of the population incubated in DMSO control. Worms were scored as dead when they failed to move in response to touch with a platinum wire.
Survival rate was dependent on the extract dilution and in most accessions an inverted U curve was obtained, which, on the one hand, it is produced by a toxic effect of the extract at high concentrations and, on the other, by the thermotolerance activity; therefore, the doses-response curve (log mg tomato vs. % worms rescued from death with respect to control) with extract dilutions, showing no toxic effects, was plotted for each accession (Fig. 5). The percentage of living (rescued) worms was calculated as rate of death worm in treatment Â 100/rate of death worm in control. Thermotolerance activity was expressed as the effective doses that produce 50% of rescued worms (ED50).

Relationship among in vivo and in vitro activities and fruit traits
To find relationships among in vivo and in vitro activities and fruit traits, hierarchical cluster analysis and PCA were performed using Infostat Software [2]. Dendrogram of fruit traits obtained by complete linkage clustering method is shown in Fig. 6a. Biplot graphic of the first two principal components shows the score plot of fruit traits and the loading plot of in vitro and in vivo activities (Fig. 6b). . Doses-response curves of worms exposed to thermal stress, which were previously incubated with serial dilutions of extracts from tomato accessions. log mg FW: logarithm of micrograms of tomato (fresh weight).  obtained by complete linkage clustering method is shown in Fig. 7a. Biplot graphic of the first two principal components shows the score plot of geographical origin and the loading plot of in vitro and in vivo activities (Fig. 7b).