Phenolic Profile, Antioxidant Activity and Anti-proliferative Activity of Crabapple Fruits

To explore the potential of crabapples as functional food, polyphenols in crabapples and ‘Fuji’ apples were extracted, and the phenolic profile, total polyphenols, antioxidant activity and anti-proliferative activity against several human cancer cells were determined. The results indicated that crabapple extracts have more abundant phenols and higher total polyphenols (from 4.46 to 46.63 mg GAE·g⁻¹ DW) compared to ‘Fuji’ apples. Crabapple extracts possessed higher antioxidant activity than apple by DPPH and ABTS analysis. All fruit extracts exhibited inhibitory effects on proliferation in different cancer cells; however, crabapple extracts performed significantly better, with half inhibitory concentration (IC₅₀) values varied from 48.34 µg·mL⁻¹ to 974.81 µg·mL⁻¹ for colon cancer cells SW480, 64.67–1466.35 µg·mL⁻¹ for stomach cancer cells BGC-803, 78.88–910.64 µg·mL⁻¹ for esophageal cancer cells CaEs-17. Besides, the red crabapples had higher antioxidant activity and anti-proliferative activity than yellow fruits. These results showed that crabapples, especially red crabapples, have great potential as a healthy food, as they are rich in phenolic compounds with high antioxidant and anti-proliferative activities to cancer cells.