Visionht c18 hl column

Quantitative analysis of six transformation product (1–6) processed by microwave processing method was determined by high-performance liquid chromatography (HPLC) (Fig. 3). The HPLC data were recorded on a Shimadzu Analytical Instrument (Shimadzu, Kyoto, Japan), equipped with a solvent degasser, a binary pump, an auto sampler and a UV detector. The separation was performed on a VisionHT C18 HL column (250 mm × 4.6 mm, 5 μm, Grace, Deerfield, USA) at the flow rate of 1.0 mL min⁻¹. The mobile phase consisted of distilled water (solvent A) and acetonitrile (solvent B) using the following gradient program: 0–20 min, 20–20% B; 20–45 min, 20–46% B; 45–50 min, 46–55% B; 50–66 min, 55–55% B. The detection wavelength and the column temperature were at 203 nm and 35 °C, respectively. The calibration curves for 20(S)-Rg₃ (1), 20(R)-Rg₃ (2), SFt₃ (3), Rk₁ (4), Rg₅ (5) and 20(S)-Rh₂ (6) showed good linearity (R² > 0.9990) in the concentration ranges (Table 1). The samples were analyzed by HPLC in three times.

HPLC analysis was conducted to quantify the phenolic compounds present in HFE based on the method of Liu et al. with minor modifications [32 (link)]. Briefly, HFE dissolved in ethanol was filtered, and injected onto a VisionHT C18-HL column (250 × 4.6 mm, 5 μm; Grace, Columbia, MD, USA). The mobile phase consisted of water with 0.5% formic acid (solvent A), and acetonitrile/methanol = 80:20 (v/v) (solvent B), at a flow rate of 1 mL/min. Peaks were monitored at 280, 320, and 360 nm with a UV–visible detector. Phenolic compounds were identified by comparing the retention time with those of authentic standards and quantified according to the calibration curves. The HPLC chromatograms of HFE were shown in Fig. 1. HPLC results showed that 1 g of HFE contained 15.69 mg of total phenolic antioxidant compounds, including 5.93 mg of procyanidin B2, 5.36 mg of epicatechin, 2.45 mg of procyanidin C1, 1.31 mg of chlorogenic acid, 0.36 mg of hyperoside, and 0.28 mg of isoquercitrin.Fig. 1

HPLC chromatograms of hawthorn fruit extract at 280, 320, and 360 nm