Characterisation, Antioxidant Activity and Chain Breaking Properties of Blighia sapida Oil Extracts

The ackee (Blighia sapida), a member of the Sapindaceae family is native to West Africa but has been naturalised in the Caribbean. Fully mature fruits are consumed in Jamaica and its diaspora. The arilli of the mature fruit is rich in monounsaturated lipids. Lipid extracts of the fruit are not currently utilised commercially. In the current study, lipid extracts of the arilli and seeds of the fully mature fruit were characterised. The acid, iodine, peroxide, and saponification values of the lipid extracts, as well as the refractive index were determined. Their antioxidant and chain breaking properties were also evaluated. Ackee arilli oil and seed oil had acid values of 3.2 ± 1.3 mg KOH/g and 4.7 ± 0.3 mg KOH/g, respectively (p > 0.05). The refractive index of ackee arilli oil and seed oil was 1.46 and 1.45, respectively (p > 0.05). Ackee seed oil had an iodine value of 48 and arilli oil 47 – 56 (g I2/100 g oil) (p > 0.05). Oil extracts from the mature arilli of the fruit had a saponification value of 211-213 mg KOH/g whereas ackee seed oil had a saponification value of 140 mg KOH/g. The peroxide values for the arilli and seed oil samples were 1.88 ± 0.35 and 19.55 ± 2.90 mEq/kg, respectively (p < 0.05), indicating that arilli oil had greater stability than ackee seed oil. The reducing capacity of ackee seed oil (3184 ± 526 %) and arilli oil (2078 ± 252 %) was not significantly different (p > 0.05). Fractionation of arilli oil extracts revealed that neutral lipids made up the major portion followed by glycolipids. Phospholipids were present in very small quantities. DPPH radical scavenging assay revealed percentage inhibitions of 3.2 % and 20.1 % for arilli and seed oils, respectively. Ackee arilli oil contained higher quantities (p < 0.05) of phenolics compounds (14.35 ± 0.66 ppm gallic acid/g) than the seed oil (11.47 ± 0.53 ppm gallic acid/g). Ackee oil exhibited several characteristic features of oils that are currently utilised commercially. Ackee oil extracts could be considered for utilisation in commercial applications in the food and cosmetic industries.