Antioxidant-rich phytochemicals in miracle berry (Synsepalum dulcificum) and antioxidant activity of its extracts.

Miracle berry is known for its unique characteristic of modifying sour flavours to sweet. Twelve phenolics were identified and quantified in the miracle berry flesh at a level from 0.3 for kaempferol to 17.8 mg/100g FW for epicatechin. Lutein and α-tocopherol were also quantified at a level of 0.4 and 5.8 mg/100g FW, respectively. The TP and TF contents were 1448.3 GA and 9.9 QR mg Equiv/100g FW for the flesh, respectively, compared with 306.7 GA and 3.8 mg QR mg Equiv/100g FW of the seeds. The free radical scavenging and reducing percentage of the flesh extract was 96.3% and 32.5% in DPPH and ABTS assays, respectively. Additionally, the flesh extract had a high FRAP of 22.9 mmol/100g. It significantly inhibited the oxidation of PUFA in fish oil as well. Thus, miracle berry could also serve as an antioxidant-rich fruit to provide health promoting function.