Determination and quantification of p-coumaric acid in pineapples (Ananas comosus) extracts using gradient mode RP-HPLC

Background: Pineapple (Ananas comosus) is a good source of phenolic compounds such as p‑coumaric acid. P‑Coumaric acid is a hydroxycinnamic acid known to possess antioxidant, antimicrobial, antimutagenic, and immunoregulatory activities. Objective: The present study aims to determine and quantify the p‑coumaric acid in the juice extract and methanol extract of unripe and ripe pineapples by gradient mode reverse‑phase high‑performance liquid chromatography (RP‑HPLC). Materials and Methods: The analysis was carried out using 0.5% phosphoric acid and 100% acetonitrile (can) as mobile phase A and B at gradient elution conditions of 0–30 min from 5% B to 80% B, 30–33 min at 80% B, 33–35 min from 80% B to 5% B, and 35–40 min at 5% B. The chromatography separation was performed using Gemini C18 column at flow rate of 0.8 mL/min and detection was made at 280 nm. Results: P‑Coumaric acid was determined at retention time of 16.16 min. Standard curves were linear at R² = 0.9973 with low limit of detection and limit of quantification being 0.0208 and 0.0694, respectively. P‑Coumaric acid showed the highest concentration in juice extract of ripe pineapple, 11.76 μg/mL compared to the methanol extract, 0.03 μg/mL, respectively. P‑Coumaric acid concentration in juice extract of unripe pineapple was 0.41 μg/mL. Conclusion: The gradient mode RP‑HPLC proved to be efficient for determination and quantification of p‑coumaric acid in pineapples extracts.