Lc 10ad pumps

For the RP-HPLC fingerprint analysis of individual phenolic compounds present in the tomato juice extract, a Shimadzu system (Shimadzu Corp., Kyoto, Japan) consisting of two LC-10AD pumps, an SCTL 10A system controller, an SPD-M 10 A photodiode array detector, and a prepacked LUNA C 18 column (4 × 259 mm, 5 μm, Phenomenex) was used. A flow rate of 1 mL/min, injection volume of 20 μL, a gradient elution of acetonitrile-water-acetic acid (5 : 93 : 2, v/v/v) (solvent A) and acetonitrile-water-acetic acid (40 : 58 : 2, v/v/v) (solvent B), and a 0-50 min solvent B from 0% to 100% were applied [18 (link)]. The tomato juice extract was dissolved using a water : methanol mixture (20 : 80, v/v) and filtered through a 0.45 μm filter (Chromafil Xtra PET-45/25, Macherey-Nagel). The separation of compounds was monitored at 260 and 320 nm. The identification was performed based on the retention times and the UV spectra of the standards and the samples.

For the HPLC analysis of SDG, a Shimadzu system (Shimadzu Corp., Kyoto, Japan) consisting of two LC-10AD pumps, an SCTL 10 A system controller, an SPD-M 10 A photo-diode array detector and a prepacked LUNA C 18 (4 × 259 mm, 5 μm, Phenomenex) was used. A flow rate of 1 mL/min and gradient elution of acetonitrile-water-acetic acid (5:93:2, v/v/v) [solvent A] and of acetonitrile-water-acetic acid (40:58:2, v/v/v) [solvent B], 0–50 min solvent B from 0 to 100%, were used [31 ]. The concentration of the sample dissolved in methanol was 2 mg/mL; the injection volume was 20 μL; the separation of compounds was monitored at 280 nm. The SDG peaks were identified and quantified by comparison with the SDG standard. A linear HPLC calibration curve for standard SDG was obtained for the concentration range of 0, 20, 40, 80, 120 and 160 µg/mL (R value 0.997). The repeatability of the whole method was tested by simultaneous analysis of 6 replicates and the coefficient of variation was <5%. The SDG standard was obtained from flaxseed alkaline hydrolysate using semi-preparative HPLC (LUNA C 18 (10 × 250 mm, 5 μm, Phenomenex)).