Green extraction and phenolic profiling of bitter melon (Momordica charantia) using UHPLC-DAD analysis: unveiling its...

This study reports for the first time the green extraction and analysis of four phenolics: gallic acid (GA), scopoletin (SC), rosmarinic acid (RA), and resveratrol (RV) in different parts (skin, pulp, seeds) of the fresh and dried fruits of bitter melon (BM). The fruits and their parts were evaluated for comparative anticancer and antidiabetic potential.

Ultrasound-assisted extraction (UAE) was used for green extraction, using solvents including ethanol (EtOH), acetone (ACt), ethyl acetate (EtAC), and water (H₂O), whereas UHPLC-DAD was employed for the simultaneous determination of phenolic content in the three parts of the two different origins of BM fruits (India and Saudi Arabia). The cell lines MRC5, MCF7, and A549 were used for anticancer assays, and α-amylase assays were performed for antidiabetic activity.

A high extract yield was observed for the skin part (192.7 mg/1 g; 19.27%) of the dried BM fruit using water as the solvent. The phenolic content yielded higher amounts of (75.04 ppm), RA (45.58 ppm), RV (11.40 ppm), and SC (6.07 ppm) in the dried BM fruit. The cytotoxicity revealed IC₅₀ values (μg/mL) of 65.23 ± 1.80 and 65.29 ± 1.77 for I2 (Indian fruit skin) in the MCF7 and A549 cell lines, and 86.74 ± 1.70 for K3 (KSA fruit pulp) in the MRC5 cell line. For α-amylase inhibition, the lowest IC₅₀ (μg/mL) of 35.89 ± 1.20 was observed for I1 (Indian fruit seeds) samples. Pearson's correlation, along with the mean differences for the extracts and phenolic content vs. solvents, fresh and dried fruit, and fruit parts, exhibited significant differences (p < 0.05).

This study highlights the potential of BM fruit as a rich source of phenolics with notable antidiabetic and anticancer properties. Further in vivo studies, such as toxicity assessments against Artemia salina, are recommended to elucidate the underlying mechanisms of these bioactivities.