Data on concentration of lipid hydroperoxides in five potato cultivars

Description

This study aimed to determine the concentration of lipid hydroperoxides in the fruit juice of five industrial potato cultivars and to assess whether significant differences exist among them. The dataset includes a hydrogen peroxide standard curve and measurements from five potato cultivars analyzed in biological triplicate. The standard curve consists of ten data points ranging from 1 to 80 µM hydrogen peroxide (H₂O₂), along with their corresponding absorbance values at 500 nm. These data show a linear relationship between hydrogen peroxide concentration and absorbance. Below the standard curve, absorbance values for Folch extracts from three biological replicates (R1, R2, and R3) of each potato cultivar are presented. Corresponding blank-corrected absorbance values (solvent + reagent) are also provided to account for background signal caused by color development in the reagent over time. The values labeled R1–R3 [H₂O₂] (µM) represent the hydrogen peroxide equivalent concentrations in each sample, calculated using the standard curve. Further details on data acquisition are provided in the “Steps to reproduce” section. Overall, the data reveal substantial variation in lipid hydroperoxide concentrations among biological replicates within each potato cultivar, limiting the ability to detect significant differences between cultivars.

Steps to reproduce

1 Preparation of Potato Fruit Juice PFJ from each variety (Kuras, Saprodi, Ydun, Stratos and a confidential cultivar designated as "Cultivar X") was prepared in three batches. The potatoes were washed thoroughly to remove dirt and sand, then processed using a twin-screw Angel Juicer 8500S (Angel® Juicer, South Korea), which produced juice and pulp. The juice was centrifuged at 4700 x g for 10 min at 4 °C in a Multifuge 3SR (Fisher Scientific™, Germany) to remove starch and insoluble plant fibers. The resulting PFJ was immediately frozen using liquid nitrogen and stored at -21 °C until further analysis. 2 Determination of Hydroperoxide Concentration by Thiocyanate Assay Lipid hydroperoxides were extracted from PFJ samples (Section 1) using a Folch extraction based on the protocol described by Dalsgaard et al. (2010), with modifications to accommodate the liquid sample matrix. In brief, the Folch extraction was carried out by mixing 2 mL of PFJ with 2 mL of MeOH. Then, 4 mL of chloroform was added, followed by 30 s of mixing. The samples were then centrifuged at 3000 rpm for 10 min at 4 °C in a Multifuge 3SR. After centrifugation, the chloroform phase was transferred to a GC-vial and stored overnight in darkness at -21 °C. The hydroperoxide concentration in Folch extracts was then determined using the thiocyanate assay (Dalsgaard et al., 2010). To prepare the iron (II)/thiocyanate reagent, three solutions were prepared. Solution I was prepared by dissolving 0.4 g of barium chloride dihydrate in 50 mL of MilliQ-water, while 0.5 g of iron (II) sulfate heptahydrate was dissolved in 50 mL of MilliQ-water. The barium chloride solution was slowly added to the iron (II) sulfate heptahydrate solution, followed by the addition of 2 mL of 10 mol/L HCl. The solution was then filtered to remove precipitated barium sulfate. Solution II was prepared by dissolving 3 g of ammonium thiocyanate in 10 mL of MilliQ-water. Solution III consisted of a chloroform-methanol mixture (1:1). The iron (II)/thiocyanate reagent was then prepared by mixing 250 μL of Solution I with 250 μL of Solution II, followed by dilution to 25 mL with Solution III. To measure the hydroperoxide concentration, 1 mL of sample was mixed with 1 mL of the iron (II)/thiocyanate reagent. After 5 min of incubation at room temperature (21 °C), the absorbance was measured at 500 nm, with 700 nm used for background correction, using an Agilent Cary 60 UV-Vis Spectrophotometer (Agilent Technologies, California, USA). A hydrogen peroxide standard curve (1-80 μmol/L) was then prepared and used to calculate the hydroperoxide concentration in the samples.

Institutions

• Aarhus University

  Central Jutland, Aarhus

Categories

Funders

• REFINES project supported by Plant2Food

  Grant ID: NNF22SA0081019

Licence